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Sample records for genus astyanax baird

  1. Cytogenetic divergence in two sympatric fish species of the genus Astyanax Baird and Girard, 1854 (Characiformes, Characidae) from northeastern Brazil

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    Medrado, Aline Souza; Ribeiro, Mavione Souza; Affonso, Paulo Roberto Antunes de Mello; Carneiro, Paulo Luíz Souza; Costa, Marco Antônio

    2012-01-01

    The fish genus Astyanax is widespread throughout the Neotropical region and is one of the most species-rich genera of the Characiformes. Cytogenetic studies of Astyanax have revealed marked intra- and interspecific diversity, with the identification of various species complexes. In this report, we describe the karyotypic structure of two sympatric species of Astyanax (Astyanax sp. and Astyanax aff. fasciatus) from the Middle Contas River basin in the northeastern Brazilian state of Bahia. Both species had 2n = 48 but differed in their karyotypic formulae. Small heterochromatic blocks and multiple nucleolar organizer regions (NORs) were identified in both species. Terminal CMA3+/DAPI− signals were observed in Astyanax sp. and A. aff. fasciatus, mostly coincident with NORs. These results show that chromosomal markers can be used to identify species in this fish complex. These markers can provide useful information for evolutionary studies and investigations on the mechanisms of chromosomal diversity in Astyanax. PMID:23271941

  2. [Description of a new species of the genus Astyanax Baird & Girard from Araguaia River basin, Brazil].

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    Garutti, V

    1999-11-01

    Astyanax argyrimarginatus sp. n. is described from the Araguaia River basin, Brazil. The new species may be diagnosed by a humeral dark spot horizontally oval, and an elongated caudal peduncle dark spot, continued to the tip of the mid caudal rays, two dark brown vertical bars on the humeral region, and a single black lateral stripe with silvered border. Forty-two to forty-six scales on lateral line; fourteen to sixteen vertical scales rows. Twenty-seven to thirty-one anal fin rays. Dentary large teeth quincuspid, inner row of pre-maxilar teeth quincuspid or hexacuspid, and one maxillary tooth. Comments on the characters which permit to recognize the new species from others with the same color pattern are made.

  3. Evolutionary history of the fish genus Astyanax Baird & Girard (1854 (Actinopterygii, Characidae in Mesoamerica reveals multiple morphological homoplasies

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    Doadrio Ignacio

    2008-12-01

    Full Text Available Abstract Background Mesoamerica is one of the world's most complex biogeographical regions, mostly due to its complex geological history. This complexity has led to interesting biogeographical processes that have resulted in the current diversity and distribution of fauna in the region. The fish genus Astyanax represents a useful model to assess biogeographical hypotheses due to it being one of the most diverse and widely distributed freshwater fish species in the New World. We used mitochondrial and nuclear DNA to evaluate phylogenetic relationships within the genus in Mesoamerica, and to develop historical biogeographical hypotheses to explain its current distribution. Results Analysis of the entire mitochondrial cytochrome b (Cytb gene in 208 individuals from 147 localities and of a subset of individuals for three mitochondrial genes (Cytb, 16 S, and COI and a single nuclear gene (RAG1 yielded similar topologies, recovering six major groups with significant phylogeographic structure. Populations from North America and Upper Central America formed a monophyletic group, while Middle Central America showed evidence of rapid radiation with incompletely resolved relationships. Lower Central America lineages showed a fragmented structure, with geographically restricted taxa showing high levels of molecular divergence. All Bramocharax samples grouped with their sympatric Astyanax lineages (in some cases even with allopatric Astyanax populations, with less than 1% divergence between them. These results suggest a homoplasic nature to the trophic specializations associated with Bramocharax ecomorphs, which seem to have arisen independently in different Astyanax lineages. We observed higher taxonomic diversity compared to previous phylogenetic studies of the Astyanax genus. Colonization of Mesoamerica by Astyanax before the final closure of the Isthmus of Panama (3.3 Mya explains the deep level of divergence detected in Lower Central America. The

  4. Evolutionary history of the fish genus Astyanax Baird & Girard (1854) (Actinopterygii, Characidae) in Mesoamerica reveals multiple morphological homoplasies

    Science.gov (United States)

    2008-01-01

    Background Mesoamerica is one of the world's most complex biogeographical regions, mostly due to its complex geological history. This complexity has led to interesting biogeographical processes that have resulted in the current diversity and distribution of fauna in the region. The fish genus Astyanax represents a useful model to assess biogeographical hypotheses due to it being one of the most diverse and widely distributed freshwater fish species in the New World. We used mitochondrial and nuclear DNA to evaluate phylogenetic relationships within the genus in Mesoamerica, and to develop historical biogeographical hypotheses to explain its current distribution. Results Analysis of the entire mitochondrial cytochrome b (Cytb) gene in 208 individuals from 147 localities and of a subset of individuals for three mitochondrial genes (Cytb, 16 S, and COI) and a single nuclear gene (RAG1) yielded similar topologies, recovering six major groups with significant phylogeographic structure. Populations from North America and Upper Central America formed a monophyletic group, while Middle Central America showed evidence of rapid radiation with incompletely resolved relationships. Lower Central America lineages showed a fragmented structure, with geographically restricted taxa showing high levels of molecular divergence. All Bramocharax samples grouped with their sympatric Astyanax lineages (in some cases even with allopatric Astyanax populations), with less than 1% divergence between them. These results suggest a homoplasic nature to the trophic specializations associated with Bramocharax ecomorphs, which seem to have arisen independently in different Astyanax lineages. We observed higher taxonomic diversity compared to previous phylogenetic studies of the Astyanax genus. Colonization of Mesoamerica by Astyanax before the final closure of the Isthmus of Panama (3.3 Mya) explains the deep level of divergence detected in Lower Central America. The colonization of Upper

  5. Evolutionary history of the fish genus Astyanax Baird & Girard (1854) (Actinopterygii, Characidae) in Mesoamerica reveals multiple morphological homoplasies.

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    Ornelas-García, Claudia Patricia; Domínguez-Domínguez, Omar; Doadrio, Ignacio

    2008-12-22

    Mesoamerica is one of the world's most complex biogeographical regions, mostly due to its complex geological history. This complexity has led to interesting biogeographical processes that have resulted in the current diversity and distribution of fauna in the region. The fish genus Astyanax represents a useful model to assess biogeographical hypotheses due to it being one of the most diverse and widely distributed freshwater fish species in the New World. We used mitochondrial and nuclear DNA to evaluate phylogenetic relationships within the genus in Mesoamerica, and to develop historical biogeographical hypotheses to explain its current distribution. Analysis of the entire mitochondrial cytochrome b (Cytb) gene in 208 individuals from 147 localities and of a subset of individuals for three mitochondrial genes (Cytb, 16 S, and COI) and a single nuclear gene (RAG1) yielded similar topologies, recovering six major groups with significant phylogeographic structure. Populations from North America and Upper Central America formed a monophyletic group, while Middle Central America showed evidence of rapid radiation with incompletely resolved relationships. Lower Central America lineages showed a fragmented structure, with geographically restricted taxa showing high levels of molecular divergence. All Bramocharax samples grouped with their sympatric Astyanax lineages (in some cases even with allopatric Astyanax populations), with less than 1% divergence between them. These results suggest a homoplasic nature to the trophic specializations associated with Bramocharax ecomorphs, which seem to have arisen independently in different Astyanax lineages. We observed higher taxonomic diversity compared to previous phylogenetic studies of the Astyanax genus. Colonization of Mesoamerica by Astyanax before the final closure of the Isthmus of Panama (3.3 Mya) explains the deep level of divergence detected in Lower Central America. The colonization of Upper Mesoamerica apparently

  6. Morphometric variation between two morphotypes within the Astyanax Baird and Girard, 1854 (Actinopterygii: Characidae) genus, from a Mexican tropical lake.

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    Ornelas-García, Claudia P; Bastir, Markus; Doadrio, Ignacio

    2014-07-01

    Phenotypic variation is important for evolutionary processes because it can allow local adaptation, promote genetic segregation, and ultimately give rise to speciation. Lacustrine systems provide a unique opportunity to study the mechanisms by which sister species can co-occur by means of ecological segregation. The fish genus Astyanax is characterized by high levels of phenotypic variability, providing an excellent model for the study of local specialization. Here, we analyze the morphological specializations through geometric morphometrics of two sympatric species described as different genera: Bramocharax caballeroi endemic to Lake Catemaco, and the widely distributed Astyanax aeneus. Additionally, we assess the correlation between phenotypic and genetic structure, and the phylogenetic signal of morphological variation. We examined body size and shape variation in 196 individuals and analyzed mitochondrial cytochrome b sequences in 298 individuals. Our results confirm the striking morphological divergence among the sympatric characids. Differences between them were mainly found in the body depth and profile and orientation of the head, where B. caballeroi in contrast with the A. aeneus, presented a fusiform body and an upward mouth. Moreover, different growth trajectories were observed among morphotypes, suggesting that a heterochronic process could be involved in the diversification of our study system. Morphological differences did not correspond with the molecular differentiation, suggesting high levels of homoplasy among the lineages of B. caballeroi morphs.

  7. Highly Similar Morphologies Between Chromosomes Bearing U2 snRNA Gene Clusters in the Group Astyanax Baird and Girard, 1854 (Characiformes, Characidae): An Evolutionary Approach in Species with 2n = 36, 46, 48, and 50.

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    Piscor, Diovani; Centofante, Liano; Parise-Maltempi, Patricia Pasquali

    2016-12-01

    Repetitive sequences and their chromosomal locations have been widely studied in species of the Astyanax genus. However, the chromosomal organization of U2 snDNA remains largely unknown. The aims of this study were to examine the chromosomal contexts of U2 snRNA and 5S rRNA genes in Astyanax species and determine the degree of chromosome morphological similarity between species with different diploid numbers. Clusters of U2 snDNA and 5S rDNA were determined in nine species of Astyanax, including two karyomorphs of Astyanax fasciatus Cuvier, 1819. All species exhibited U2 snDNA clusters on two chromosome pairs, except Astyanax mexicanus De Filippi, 1853 (one pair). The 5S rDNA clusters were located on one chromosome pair in Astyanax altiparanae Garutti and Britski, 2000, and Astyanax marionae Eigenmann, 1911, two pairs in Astyanax abramis Jenyns, 1842, Astyanax asuncionensis Géry, 1972, Astyanax bockmanni Vari and Castro, 2007, Astyanax eigenmanniorum Cope, 1894, A. fasciatus (karyomorphs I and II), and Astyanax schubarti Britski, 1964, and four pairs in A. mexicanus. The relationships between the repetitive sequences in different species suggest that A. schubarti and A. mexicanus exhibit an unusual U2 snDNA chromosomal format as a result of events occurring in the evolutionary history of the Astyanax group.

  8. Karyotypic diversity among three species of the genus Astyanax (Characiformes: Characidae).

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    Nishiyama, P B; Vieira, M M R; Porto, F E; Borin, L A; Portela-Castro, A L B; Santos, I C M

    2016-06-01

    The group Incertae sedis within the Characidae family currently includes 88 genera, previously included in the subfamily Tetragonopterinae. Among them is the genus Astyanax comprising a group of species with similar morphology and widely distributed in the Neotropics. Thus, the present study aimed to analyze the karyotype diversity in Astyanax species from different watersheds by conventional Giemsa staining, C-banding and fluorescence in situ hybridization (FISH rDNA 18S) probe.specimens of Astyanax aff. paranae belonging to the "scabripinnis complex", Astyanax asunsionensis and Astyanax aff. bimaculatus were analyzed". Two sympatric karyomorphs were observed in Astyanax.aff paranae, one of them having2n=48andthe other one with 2n=50 chromosomes. Other population of this same species also presented 2n=50 chromosomes, but differing in the karyotype formula and with macro supernumerary chromosome found in 100% of the cells in about 80%of females analyzed. Two population of A. asuncionensis and one population of Astyanax. aff. bimaculatus, also showed a diploid number of 50 chromosomes, but also differing in their karyotype formulas. Therefore, A. asuncionensis was also characterized by intraspecific chromosome diversity. The C-banding analysis was able to demonstrate a distinctable to demonstrate a distinct pattern of heterochromatin differing A. asuncionensis from Astyanax aff. paranae and Astyanax aff. bimaculatus. The supernumerary chromosome of Astyanax aff. paranae proved completely heterochromatic. Only Astyanax.aff. bimaculatus multiple showed multiple sites of nucleolar organizing regions. The other species were characterized by having a simple system of NOR. These data contributes to the know ledge of the existing biodiversity in our fish fauna, here highlighted by the inter- and intraspecific chromosomal diversity in the genus Astyanax.

  9. Population structure of two Astyanax Baird & Girard, 1854 (Teleostei, Characidae species from upper Paraguaçu river

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    Alexandre Clistenes de Alcântara Santos

    2008-02-01

    Full Text Available The fishes of the family Characidae are among the main species of fresh water fishes in South America. In this work, some aspects of the population structure of two Astyanax species were assessed. The fishes were caught in Santo Antônio and São José rivers, in the Paraguaçu basin, by standardized monthly samplings adapted to the microhabitats. Astyanax sp. b (São José river presented larger size than Astyanax sp. a (Santo Antônio river. The length-weight relationship showed positive allometric growth for Astyanax sp. a, and negative for Astyanax sp. b. Both the species showed a long reproductive period, with higher activities in dry period.Os peixes da família Characidae estão entre os principais representantes de peixes de água doce da região Neotropical. Este trabalho apresenta alguns aspectos da estrutura populacional de duas espécies de Astyanax coletadas a partir de amostragens mensais padronizadas e adaptadas a diferentes microhabitats, em trechos dos rios Santo Antônio e São José, tributários do alto curso do rio Paraguaçu. Astyanax sp. b, coletada no rio São José apresentou maior tamanho que Astyanax sp. a, coletada no rio Santo Antônio. A relação peso-comprimento indicou um crescimento alométrico positivo para Astyanax sp. a e negativo para Astyanax sp. b. Ambas as espécies apresentaram um longo período reprodutivo, com maior atividade reprodutiva no período seco.

  10. Astyanax hastatus Myers, 1928 (Teleostei, Characidae): A new species complex within the genus Astyanax?

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    2009-01-01

    Four populations of Astyanax hastatus Myers 1928 from the Guapimirim River basin (Rio de Janeiro State) were analyzed and three distinct cytotypes identified. These cytotypes presented 2n = 50 chromosomes, with 4M+8SM+10ST+28A (Cytotype A), 8M+10SM+14ST+18A (Cytotype B), 6M+8SM+4ST+32A (Cytotype C) and scanty heterochromatin, mainly located throughout pericentromeric regions of several chromosomal pairs. No homologies with the As-51 satellite DNA were observed in the three cytotypes, although all of them presented multiple 18S rDNA sites, as detected by both silver nitrate staining and FISH (fluorescent in situ hybridization). The application of the term “species complex” in Astyanax is discussed from a cytotaxonomic viewpoint. PMID:21637509

  11. A new remarkable and Critically Endangered species of Astyanax Baird & Girard (Characiformes: Characidae) from Chapada Diamantina, Bahia, Brazil, with a discussion on durophagy in the Characiformes.

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    Zanata, Angela M; Lima, Flávio C T; Dario, Fabio DI; Gerhard, Pedro

    2017-02-20

    Astyanax brucutu is described from the rio Pratinha, rio Paraguaçu basin, Bahia, Brazil. The new species is promptly distinguished from other characids by having four, rarely three, robust, rounded, and usualy tricuspid teeth on inner premaxillary series and similar teeth on dentary. The species is furthermore characterized by a series of unusual character states in the Characidae, including head blunt in lateral and dorsal views, longitudinal foreshortening of lower jaw, ventral margin of third infraorbital distinctly separated from horizontal limb of preopercle, leaving a broad area without superficial bones, mesethmoid anteroventrally expanded, and adductor mandibulae and primordial ligament remarkably developed. Analysis of gut contents of adults revealed the almost exclusive presence of crushed shells of tiny gastropods of the family Hydrobiidae. The robust anatomy of jaws, teeth, muscles and associated ligaments are likely adaptations to durophagy, a feeding strategy unusual among characids. Astyanax brucutu is known only from its type locality, an approximately 670 m long, transparent and isolated perennial epigean watercourse surrounded by subterranean or intermittent rivers. The distinctive combination of environmental features characterizing the area of occurrence of the new species is not observed elsewhere in the basin or adjacent basins. A series of severe anthropogenic impacts, associated with the restricted geographic range of the species, implies that A. brucutu should be regarded as Critically Endangered (CR) according to IUCN Red List Criteria.

  12. Origin of B chromosomes in the genus Astyanax (Characiformes, Characidae) and the limits of chromosome painting.

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    de A Silva, Duílio M Z; Daniel, Sandro Natal; Camacho, Juan Pedro M; Utsunomia, Ricardo; Ruiz-Ruano, Francisco J; Penitente, Manolo; Pansonato-Alves, José Carlos; Hashimoto, Diogo Teruo; Oliveira, Claudio; Porto-Foresti, Fábio; Foresti, Fausto

    2016-06-01

    Eukaryote genomes are frequently burdened with the presence of supernumerary (B) chromosomes. Their origin is frequently investigated by chromosome painting, under the hypothesis that sharing the repetitive DNA sequences contained in the painting probes is a sign of common descent. However, the intragenomic mobility of many anonymous DNA sequences contained in these probes (e.g., transposable elements) adds high uncertainty to this conclusion. Here we test the validity of chromosome painting to investigate B chromosome origin by comparing its results for seven B chromosome types in two fish species genus Astyanax, with those obtained (1) by means of the physical mapping of 18S ribosomal DNA (rDNA), H1 histone genes, the As51 satellite DNA and the (AC)15 microsatellite, and (2) by comparing the nucleotide sequence of one of these families (ITS regions from ribosomal DNA) between genomic DNA from B-lacking individuals in both species and the microdissected DNA from two metacentric B chromosomes found in these same species. Intra- and inter-specific painting suggested that all B chromosomes that were assayed shared homologous DNA sequences among them, as well as with a variable number of A chromosomes in each species. This finding would be consistent with a common origin for all seven B chromosomes analyzed. By contrast, the physical mapping of repetitive DNA sequences failed to give support to this hypothesis, as no more than two B-types shared a given repetitive DNA. Finally, sequence analysis of the ITS regions suggested that at least some of the B chromosomes could have had a common origin.

  13. A phylogeny of Astyanax (Characiformes: Characidae) in Central and North America.

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    Schmitter-Soto, Juan J

    2016-05-06

    A phylogeny is presented for 34 species of Astyanax, 27 of them once included within A. aeneus or A. fasciatus in Central America and Mexico, based on 52 morphological characters (mostly osteological, but also pigmentation and meristics), with three outgroups. Monophyly is not supported for A. aeneus s. lat., as Brazilian species such as A. fasciatus s. str. and others occur also within that clade. There were only five resolved clades, three of them including both Brazilian and Central American species, one purely Nicaraguan, and one for central-northern Mexico and Texas. Coincidence with previous cladistic hypotheses is only partial. The genus Bramocharax Gill is not recovered, and thus confirmed as a synonym of Astyanax Baird & Girard. The findings point at a more complex biogeographic history of the region than usually recognized.

  14. Chromosomal microstructure diversity in three Astyanax (Characiformes, Characidae) species: comparative analysis of the chromosomal locations of the 18S and 5S rDNAs.

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    Piscor, Diovani; Alves, Anderson Luís; Parise-Maltempi, Patricia Pasquali

    2015-02-01

    The species of genus Astyanax is widely distributed in freshwater neotropical zones. Astyanax is considered to be taxonomically confused, similar to other genera placed incertae sedis in Characidae. The cytogenetics of this genus is well characterized; species vary widely in diploid number, from 2n=36 chromosomes in Astyanax schubarti to 2n=50 for most species studied. The size, number, and position of different cytological markers vary among species and populations of Astyanax. We analyzed the karyotypes of individuals from three Astyanax species (Astyanax abramis, Astyanax altiparanae, and Astyanax eigenmanniorum) from populations not previously analyzed. We describe variations in several cytogenetic markers and the karyotypic relationships between them, specifically focusing on the characteristics of the conserved and divergent locations of the ribosomal genes. Our data are useful for establishing relationships between species and for investigating the karyotype evolution within the genus.

  15. Basic cytogenetics and physical mapping of ribosomal genes in four Astyanax species (Characiformes, Characidae) collected in Middle Paraná River, Iguassu National Park: considerations on taxonomy and systematics of the genus

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    Paiz, Leonardo Marcel; Baumgärtner, Lucas; da Graça, Weferson Júnio; Margarido, Vladimir Pavan

    2015-01-01

    Abstract Karyotypes and chromosomal characteristics of both minor and major rDNAs in four fish species known popularly as “lambaris”, namely Astyanax abramis (Jenyns, 1842), Astyanax asuncionensis Géry, 1972, Astyanax correntinus (Holmberg, 1891) and Astyanax sp. collected from downstream of the Iguassu Falls (Middle Paraná River basin), preservation area of the Iguassu National Park, were analyzed by conventional and molecular protocols. Astyanax abramis had diploid chromosome number 2n=50 (4m+30sm+8st+8a) and single AgNORs (pair 22), Astyanax asuncionensis had 2n=50 (8m+24sm+6st+12a) and single AgNORs (pair 20), Astyanax sp. had 2n=50 (4m+26sm+8st+12a) and single AgNORs (pair 25), and Astyanax correntinus had 2n=36 (12m+16sm+2st+6a) and multiple AgNORs (pairs 12, 15, 16, 17). FISH with 18S rDNA showed a single site for Astyanax abramis, Astyanax asuncionensis and Astyanax sp. and multiple for Astyanax correntinus (14 sites). FISH with 5S rDNA showed single 5S-bearing loci chromosome pair only for Astyanax asuncionensis and multiple for Astyanax abramis (four sites), Astyanax correntinus (five sites) and Astyanax sp. (four sites). Distinct distribution patterns of heterochromatin were observed for karyotypes of all species, with the exception of the first acrocentric chromosome pair characterized by centromeric, interstitial-proximal and telomeric blocks of heterochromatin on the long arm, which may represent homeology between karyotypes of Astyanax abramis and Astyanax asuncionensis. Our study showed species-specific characteristics which can serve in diagnosis and differentiation between Astyanax abramis and Astyanax asuncionensis, considered cryptic species, as well as strengthening the occurrence of a species of Astyanax not yet described taxonomically. In addition, the data obtained from first cytogenetic studies in Astyanax correntinus suggest a high similarity with Astyanax schubarti Britski, 1964, suggesting that these species may belong to the same

  16. Highlighting Astyanax Species Diversity through DNA Barcoding

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    Oliveira, Carlos Alexandre Miranda; de Melo, Filipe Augusto Gonçalves; Bertaco, Vinicius de Araújo; de Astarloa, Juan M. Díaz; Rosso, Juan J.; Foresti, Fausto; Oliveira, Claudio

    2016-01-01

    DNA barcoding has been used extensively to solve taxonomic questions and identify new species. Neotropical fishes are found in a wide variety of shapes and sizes, with a large number of species yet to be described, many of which are very difficult to identify. Characidae is the most species-rich family of the Characiformes, and many of its genera are affected by taxonomic uncertainties, including the widely-distributed, species-rich genus Astyanax. In this study, we present an extensive analysis of Astyanax covering almost its entire area of occurrence, based on DNA barcoding. The use of different approaches (ABGD, GMYC and BIN) to the clustering of the sequences revealed ample consistency in the results obtained by the initial cutoff value of 2% divergence for putative species in the Neighbor-Joining analysis using the Kimura-2-parameter model. The results indicate the existence of five Astyanax lineages. Some groups, such as that composed by the trans-Andean forms, are mostly composed of well-defined species, and in others a number of nominal species are clustered together, hampering the delimitation of species, which in many cases proved impossible. The results confirm the extreme complexity of the systematics of the genus Astyanax and show that DNA barcoding can be an useful tool to address these complexes questions. PMID:27992537

  17. Osteología de Astyanax aurocaudatus Eigenmann, 1913 (Pisces, Characidae, con notas sobre la validez de Carlastyanax Géry, 1972

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    Ruiz-C., R. I.

    2006-06-01

    Full Text Available Osteology of Astyanax aurocaudatus, Eigenmann, 1913 (Pisces, Characidae, with notes on the validity of Carlastyanax, Géry, 1972. The taxonomic status of Astyanax aurocaudatus is difficult to interpret as no relevant osteological data are available to date. In the present paper we studied the osteological, morphometric and meristic characters of this species. The osteological characters of A. aurocaudatus found include the number and shape of premaxilla, maxilla and dentary teeth, second infraorbital separate from the preopercle, anal fins with pterygiophores that differ as towards the anterior, and presence of supra–orbital. These and other characters, body shape and coloring pattern, coincide with descriptions for the genus Astyanax. The characters describing the genus Carlastyanax therefore correspond to incorrect observations and the studied species is situated in the genus Astyanax. Carlastyanax is here considered a synonym of Astyanax.

  18. Comparative cytogenetics in Astyanax (Characiformes: Characidae with focus on the cytotaxonomy of the group

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    Renata Cristina Claudino de Oliveira Tenório

    Full Text Available Astyanax is a diverse group of Neotropical fishes, whose different forms occupy different environments. This great diversity is also reflected on cytogenetic aspects and molecular markers, which have repeatedly been demonstrated by cytogenetic studies. In order to characterize the karyotype of species of this genus, six species were studied: Astyanax altiparanae, A.argyrimarginatus, A. elachylepis, A. xavante, and two new species provisionally called Astyanax sp. and A. aff. bimaculatus. A detailed cytogenetic study based on conventional staining with Giemsa, AgNORs, C-banding, base-specific fluorochromes, and FISH using ribosomal genes 18S and 5S was conducted, aiming to understand some of the chromosomal mechanisms associated with the high diversification that characterizes this group and culminated with the establishment of these species. The results showed 2n = 50 chromosomes for five species and a karyotype with 52 chromosomes in Astyanax sp. Small variations in the macrostructure of the karyotypes were identified, which were quite relevant when analyzed by classical banding, fluorochromes, and FISH methods. These differences among Astyanax spp. (2n = 50 are largely due to changes in the amount and types of heterochromatic blocks. Astyanax sp (2n = 52, in addition to variations due to heterochromatic blocks, has its origin possibly by events of centric fission in a pair of chromosomes followed by minor rearrangements.These results show an interesting karyotypic diversity in Astyanax and indicate the need of a review of the group referred as A. aff. bimaculatus and the description of Astyanax sp., including the possibility of inclusion of this unit in another genus.

  19. Life cycle of Cyclestheria hislopi (Baird, 1859) (Crustacea, Branchiopoda).

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    Yashima, M N; Baldochi, A; Rocha, O

    2011-05-01

    The Conchostraca (clam shrimps) are a group of microcrustaceans found in freshwater habitats. They inhabit the benthos, yet many can swim actively and are often associated with macrophytes. They are filter-feeders, deriving their food from suspended particles or solids stirred up from the bottom. In Brazil, five species have been recorded and the life cycle of one of these, Cyclestheria hislopi (Baird, 1859) was investigated in this study. Specimens were collected from fish-farming tanks in upstate São Paulo and from the floodplain of the Miranda River, in the Mato Grosso swamplands of center-west, Brazil. We determined the following variables: post-embryonic development, duration of life cycle (longevity), mean period between broods, duration of instars and individual growth. Taxonomic features of the Cyclestheria sp. specimens from Mato Grosso were also assessed to check the possibility that they belonged to another species of the same genus or a separate ecotype of C. hislopi.

  20. A new species of Cacatuocotyle (Monogenea, Dactylogyridae) parasitizing two species of Astyanax (Ostariophysi, Characidae) in southern Brazil.

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    Gallas, Moisés; Calegaro-Marques, Cláudia; Amato, Suzana B

    2014-10-01

    A new species of Cacatuocotyle is described from the external surface of Astyanax aff. fasciatus and Astyanax jacuhiensis from Lake Guaíba, State of Rio Grande do Sul, Brazil. It differs from the other three species of the genus, recorded from Mexico and the State of Paraná, Brazil, by possessing an accessory piece with a long proximal portion, a U-shaped bar with irregular posterior margin in its midportion, and a haptor containing two circular thickenings with muscular anterior margins. Only one monogenean species, Urocleidoides astyanacis (= Characithecium costaricensis) was recorded for the host Astyanax aff. fasciatus, whereas none were known for A. jacuhiensis. This paper records a new host (A. jacuhiensis) for monogeneans in southern Brazil and extends southward with the geographical distribution of the genus Cacatuocotyle to the State of Rio Grande do Sul, Brazil.

  1. Anesthesia in a Baird's tapir (Tapirus bairdii).

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    Trim, C M; Lamberski, N; Kissel, D I; Quandt, J E

    1998-06-01

    A Baird's tapir (Tapirus bairdii) was satisfactorily immobilized on two occasions with i.m. detomidine (0.065-0.13 mg/kg) and butorphanol (0.13-0.2 mg/kg). On the second occasion, anesthesia was induced by i.v. administration of ketamine (2.2 mg/kg). Twenty minutes later, endotracheal intubation was performed after an additional i.v. injection of ketamine (1.5 mg/kg). Anesthesia was maintained with isoflurane, which provided excellent conditions for radiology and surgery. Anesthesia was associated with hypoxemia when the tapir was allowed to breathe air and with hypoventilation. Mean arterial pressure remained satisfactory. No antagonist drugs were administered, and recovery from anesthesia was rapid and smooth.

  2. Evolution and development in the cavefish Astyanax

    OpenAIRE

    2009-01-01

    The teleost Astyanax mexicanus is a single species consisting of two radically different forms: a sighted pigmented surface-dwelling form (surface fish) and a blind depigmented cave dwelling form (cavefish). The two forms of Astyanax have favorable attributes, including descent from a common ancestor, ease of laboratory culture, and the ability to perform genetic analysis, permitting their use as a model system to explore questions in evolution and development. Here we review current research...

  3. Astyanax vermilion and Astyanax burgerai: new characid fishes (Ostariophysi: Characiformes from Northeastern Bahia, Brazil

    Directory of Open Access Journals (Sweden)

    Angela M. Zanata

    Full Text Available Two new Astyanax species, A. vermilion, from rio Almada and rio Cachoeira, and A. burgerai, from rio Almada, Bahia State, Brazil, are described. Astyanax vermilion is distinguished from most of its congeners and from all other Astyanax species known from northeastern Brazilian drainages by having distal portion of pelvic fins dark, a combination of sexually dimorphic characters, posteroventral portion of body and fins (except pectoral reddish in life, and inconspicuous humeral and caudal spots. It also differs by having highest body depth just anterior of dorsal-fin origin, 32-34 lateral-line scales, and presence of one or two maxillary teeth. Astyanax burgerai is diagnosed by the presence of two vertically elongated humeral blotches, absence of a conspicuous and broad dark midlateral stripe (at least on anterior half of body, body highest along vertical slightly behind midlength of pectoral fin, 31-34 lateral-line scales, and two or three teeth on premaxillary outer series.

  4. Variación morfológica de las especies de Astyanax, subgénero Zygogaster (Teleostei, Characidae

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    Ruiz-C., R. I.

    2011-06-01

    Full Text Available Morphological variation of Astyanax species, subgenus Zygogaster (Teleostei, Characidae The diverse Neotropical fish genus Astyanax inhabits a variety of aquatic environments. As with other species in this genus, the taxonomic status and phylogenetic relationships of species of this subgenus remain largely undetermined. Based on 354 individuals, we analyzed the morphological variation of four species of the subgenus Zygogaster (A. atratoensis, A. caucanus, A. filiferus, and A. magdalenae using procrustes analysis and compared findings with two species of the sister group: subgenus Poecilurichthys (A. orthodus and A. superbus. The PCA (Principal Component Analysis and CVA (Canonical Variates Analysis showed morphological affinity between the subgenera and indicated variance in body depth, anterior trend of dorsal fin origin and humeral spot, depression on the dorsal surface of the skull, and ventral displacement of the orbit and snout. The variation in these structures may provide evidence supporting adaptive speciation as an alternative to speciation driven by geographical isolation.

  5. Astyanax transgenesis and husbandry: how cavefish enters the laboratory.

    Science.gov (United States)

    Elipot, Yannick; Legendre, Laurent; Père, Stéphane; Sohm, Frédéric; Rétaux, Sylvie

    2014-08-01

    Astyanax mexicanus, a teleost fish comprising both sighted river-dwelling and blind cave-dwelling morphs, is becoming increasingly used in the field of developmental and evolutionary biology. Thus, new experimental and technological tools are needed on this emerging fish model by the expanding scientific community. Here, we describe Astyanax husbandry and egg spawning habits, a prerequisite to the successful establishment of Astyanax transgenic lines. We then compare two different transgenesis methods on both surface and cave Astyanax. Both meganuclease (I-SceI)- and transposase (Tol2)-mediated transgenesis are equivalently efficient, resulting in ∼40% mosaic transgenic fish in F0. Furthermore, the transmission rate was analyzed in F1 in the case of the I-SceI method and was found to be 16%. Finally, the transgene was found stable up the F3 generation, demonstrating the feasibility of generating stable transgenic lines in Astyanax and opening a wide range of possibilities for this fish model.

  6. Conspecific attraction in a grassland bird, the Baird's Sparrow

    Science.gov (United States)

    Ahlering, M.A.; Johnson, D.H.; Faaborg, J.

    2006-01-01

    Territorial songbirds generally use song to defend territories and attract mates, but conspecific song may also serve as a cue to attract other male songbirds to a breeding site. Although known to occur in some colonial and forest-associated species, only recently have investigators examined conspecific attraction in grassland species. We used a playback experiment to examine the possible role of conspecific attraction for males searching for potentially suitable breeding habitat in a grassland specialist, the Baird's Sparrow (Ammodramus bairdii). Experimental playback plots and control plots with similar landscape and vegetation characteristics were established at two sites in North Dakota. Baird's Sparrows colonized three of six experimental plots and none of six control plots. Males on experimental plots established territories adjacent to the playback stations and were sometimes observed counter-singing with the playback of conspecific songs. Vegetation characteristics were similar on all study plots, and did not explain differences in bird density on our treatment plots. Although we found that playback of conspecific songs attracted male Baird's Sparrows to previously unoccupied, potentially suitable habitat, further experiments are needed to examine the importance of conspecific attraction relative to other cues that birds may use, such as vegetation features. The conservation and management implications of conspecific attraction are not completely understood, but the presence of conspecifics should be considered as a potential cue in habitat selection by all species of birds. ?? 2006 The Author(s).

  7. The complex origin of Astyanax cavefish

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    Gross Joshua B

    2012-06-01

    Full Text Available Abstract Background The loss of phenotypic characters is a common feature of evolution. Cave organisms provide excellent models for investigating the underlying patterns and processes governing the evolutionary loss of phenotypic traits. The blind Mexican cavefish, Astyanax mexicanus, represents a particularly strong model for both developmental and genetic analyses as these fish can be raised in the laboratory and hybridized with conspecific surface form counterparts to produce large F2 pedigrees. As studies have begun to illuminate the genetic bases for trait evolution in these cavefish, it has become increasingly important to understand these phenotypic changes within the context of cavefish origins. Understanding these origins is a challenge. For instance, widespread convergence on similar features renders morphological characters less informative. In addition, current and past gene flow between surface and cave forms have complicated the delineation of particular cave populations. Results Past population-level analyses have sought to: 1 estimate at what time in the geological past cave forms became isolated from surface-dwelling ancestors, 2 define the extent to which cave form populations originated from a common invasion (single origin hypothesis or several invasions (multiple origin hypothesis, and 3 clarify the role of geological and climatic events in Astyanax cavefish evolution. In recent years, thanks to the combined use of morphological and genetic data, a much clearer picture has emerged regarding the origins of Astyanax cavefish. Conclusions The consensus view, based on several recent studies, is that cave forms originated from at least two distinct ancestral surface-dwelling stocks over the past several million years. In addition, each stock gave rise to multiple invasions of the subterranean biotope. The older stock is believed to have invaded the El Abra caves at least three times while the new stock separately invaded the

  8. Population genetic patterns revealed by microsatellite data challenge the mitochondrial DNA based taxonomy of Astyanax in Mexico (Characidae, Teleostei).

    Science.gov (United States)

    Hausdorf, Bernhard; Wilkens, Horst; Strecker, Ulrike

    2011-07-01

    Astyanax has become an important model system for evolutionary studies of cave animals. We investigated correlations of population genetic patterns revealed by microsatellite data and phylogeographic patterns shown by mitochondrial DNA sequences in Mexican cave and surface fish of the genus Astyanax (Characidae, Teleostei) to improve the understanding of the colonization history of this neotropical fish in Central and North America and to assess a recent taxonomic classification. The distribution of nuclear genotypes is not congruent with that of the mitochondrial clades. Admixture analyses suggest there has been nuclear gene flow between populations defined by different mitochondrial clades. The microsatellite data indicate that there was mitochondrial capture of a cave population from adjacent populations. Furthermore, gene flow also occurred between populations belonging to different nuclear genotypic clusters. This indicates that neither the nuclear genotypic clusters nor the mitochondrial clades represent independent evolutionary units, although the mitochondrial divergences are high and in a range usually characteristic for different fish species. This conclusion is supported by the presence of morphologically intermediate forms. Our analyses show that the Trans-Mexican Volcanic Belt limited gene flow, but has been crossed by Astyanax several times. In Yucatán, where obvious geographic barriers are missing, the incongruence between the distribution of nuclear and mitochondrial markers reflects random colonization events caused by inundations or marine transgressions resulting in random phylogeographic breaks. Thus, conclusions about the phylogeographic history and even more about the delimitation of species should not be based on single genetic markers.

  9. Embryonal rhabdomyosarcoma in an immature Baird's tapir (Tapirus bairdii).

    Science.gov (United States)

    Bonar, Christopher J; Lewandowski, Albert H; Skowronek, Anthony J

    2007-03-01

    An immature Baird's tapir (Tapirus bairdii) with a history of seizure-like episodes developed signs of respiratory disease. The initial clinical diagnosis was pneumonia, and antibiotic therapy was started. The animal failed to improve after 14 days of therapy and developed unilateral, bloody nasal discharge. Endoscopic examination and radiography revealed a soft tissue mass in the nasopharynx depressing the soft palate. The tapir died 32 days after initial presentation. Histologic examination of the mass demonstrated a mesenchymal tumor composed of spindle cells with elongate nuclei forming densely packed fascicles. The neoplastic spindle cells showed prominent cross-striations. Immunohistochemistry revealed the cells to be positive for desmin and myoglobin, but negative for smooth muscle actin, confirming diagnosis of rhabdomyosarcoma. Embryonal rhabdomyosarcoma is the most common nasopharyngeal soft tissue tumor of humans, and it has been reported infrequently in dogs, horses, and pigs. Neoplasia should be a differential diagnosis in cases of unilateral nasal discharge and inspiratory stridor, even in young animals.

  10. A supplementary description of Cypridina mariae and rediagnosis of the genus Cylindroleberis (Ostracoda: Myodocopa: Cylindroleberididae.

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    Anna E Syme

    Full Text Available The ostracod family Cylindroleberididae is based on the genus Cylindroleberis Brady, 1868, and has a complicated nomenclatural history. The type species of Cylindroleberis is Cypridina mariae Baird, 1850. Baird described only the carapace, which had been considered lost. Thus, there was no reference point for the concept C. mariae or the genus Cylindroleberis. Baird's material has now been found in the Natural History Museum, London, U.K., and is illustrated here. To clarify the taxonomic status of C. mariae and Cylindroleberis, specimens were obtained from near the type locality, and a supplementary description is presented. This includes description of appendages, particularly the first antenna and mandible, which contain important diagnostic characters. This supplementary description provides important information about C. mariae, allowing a revision of the genus Cylindroleberis, and establishing a framework for future biological research on this ostracod group.

  11. Suspected neonatal isoerythrolysis in two Baird's tapirs (Tapirus bairdii).

    Science.gov (United States)

    Wack, R F; Jones, A A

    1997-09-01

    Two Baird's tapir (Tapirus bairdii) calves born at the Columbus Zoo from the same sire and dam developed hemolytic anemia that was consistent in history and clinical signs with neonatal isoerythrolysis (NI). One calf developed severe, fatal hemolytic anemia after being fed maternal colostrum, and the other developed moderate hemolytic anemia after being fed equine colostrum. No cross-reactivity was demonstrated between sire and dam blood samples, and both tapirs possessed serum antibodies reactive against equine blood group Ca and antigens reactive with several equine blood group D antibodies. Electrophoresis demonstrated significant genetic diversity between tapir and equine blood proteins. Agglutination testing demonstrated strong reactivity between a far greater percentage of equine colostrum samples when tested against sire and dam tapir blood (61% and 65%, respectively) than would be expected for equine blood (2%). These data are suggestive of a diagnosis of NI but are not definitive. Further study is required to determine whether NI occurs in tapirs and whether equine colostrum is harmful to tapir calves.

  12. Distinct classical and molecular cytogenetics of Astyanax marionae and A. fasciatus (Characiformes: Characidae): a comparative study of the organization of heterochromatin and repetitive genes

    Indian Academy of Sciences (India)

    DIOVANI PISCOR; LIANO CENTOFANTE; PATRICIA PASQUALI PARISE-MALTEMPI

    2017-09-01

    Genus Astyanax is well distributed in Neotropical freshwater environments and its taxonomic position is uncertain, as is the case with other Characidae genera allocated in the group incertae sedis. This study aimed to analyse the karyotype of different populations of Astyanax fasciatus (Corumbataí River basin) using Giemsa staining, C-band technique, and fluorescence in situ hybridization for the H3 histone and 5S rRNA genes, in addition we describe for the first time the chromosomal organization of H3 histone and 5S rRNAgenes in A. marionae (ParaguayRiver basin). Chromosomes of three A. fasciatus populations were analysed (two with 2n = 50 and one with 2n = 48) and the heterochromatin was organized in two forms (blocks with blurred boundaries and distinct blocks). H3 histone and 5S rRNA genes were observed in all the three populations of A. fasciatus on two chromosome pairs (one metacentric chromosome showing H3 histone and 5S rRNA gene clusters). In A. marionae (2n = 48), H3 histone and5S rRNA genes were observed in one acrocentric chromosome pair (different pairs). Further, differences between karyotypes and heterochromatin, as well as the chromosomal organization of H3 histone and 5S rRNA genes in Astyanax species, focussing on chromosome evolution in the group are discussed.

  13. Chromosomal Mapping of Repetitive DNA Sequences in Five Species of Astyanax (Characiformes, Characidae) Reveals Independent Location of U1 and U2 snRNA Sites and Association of U1 snRNA and 5S rDNA.

    Science.gov (United States)

    Silva, Duilio M Z A; Utsunomia, Ricardo; Pansonato-Alves, José C; Oliveira, Cláudio; Foresti, Fausto

    2015-01-01

    Astyanax is a genus of Characidae fishes currently composed of 155 valid species. Previous cytogenetic studies revealed high chromosomal diversification among them, and several studies have been performed using traditional cytogenetic techniques to investigate karyotypes and chromosomal locations of 18S and 5S rDNA genes. However, only a few studies are currently available about other repetitive sequences. Here, the chromosomal location of small nuclear RNA genes, identified as U1 and U2 snRNA clusters, was established and compared to the distribution of 5S rDNA and histone clusters in 5 Astyanax species (A. paranae, A. fasciatus, A. bockmanni, A. altiparanae, and A. jordani) using FISH. The cytogenetic mapping of U1 and U2 snRNA demonstrated a conserved pattern in the number of sites per genome independent of the location in Astyanax species. The location of the U1 snRNA gene was frequently associated with 5S rDNA sequences, indicating a possible interaction between the distinct repetitive DNA families. Finally, comparisons involving the location of U1 and U2 snRNA clusters in the chromosomes of Astyanax species revealed a very diverse pattern, suggesting that many rearrangements have occurred during the diversification process of this group. © 2015 S. Karger AG, Basel.

  14. Rapid ongoing decline of Baird's tapir in Cusuco National Park, Honduras.

    Science.gov (United States)

    McCann, Niall P; Wheeler, Phil M; Coles, Tim; Bruford, Michael W

    2012-12-01

    During the International Tapir Symposium 16-21 Oct 2011, the conservation of Baird's tapir (Tapirus bairdii) in Honduras received a boost with the signing of a memorandum of understanding between the Minister Director of the Honduran Institute of Conservation and Forestry (ICF) and the Tapir Specialist Group (TSG). Despite this agreement, accelerating levels of hunting and habitat loss continue to pose a threat to Baird's tapir in Honduras. An ongoing study in Cusuco National Park in northwestern Honduras has been monitoring changes in population dynamics of Baird's tapir since 2006 through the collection of occupancy data. The study has identified an increase in hunting pressure, coinciding with a drastic decline in the encounter rate with Baird's tapir spoor. Here, we examine the significance of a range of demographic variables on Baird's tapir occupancy in Cusuco National Park using the software PRESENCE, and simulate the effects of different management strategies on the future dynamics of the population using the stochastic simulation software VORTEX. The predictions of the theoretical population models are compared to observed changes in occupancy levels. We found that non-intervention resulted in the local extinction of Baird's tapir within a very short time frame, but that various intervention models enabled the population to recover to near carrying capacity. Occupancy and extinction probability were shown to respond markedly to the increase in hunting pressure; and occupancy models supported the future population predictions generated by VORTEX. Our study suggests that immediate intervention is required to reduce hunting pressure to near historical levels to prevent the imminent local extinction of the species.

  15. Fencing with Words: A History of Writing Instruction at Amherst College during the Era of Theodore Baird, 1938-1966. Refiguring English Studies Series.

    Science.gov (United States)

    Varnum, Robin

    Citing the revolutionary ideas that Theodore Baird brought to his freshman composition classes at Amherst College (Massachusetts)--ideas such as requiring students to write often and from experience--this book examines the innovative work and groundbreaking ideas of Baird and his staff. The book focuses on Baird's pedagogy and his belief in a…

  16. Chromosomal mapping of H3 histone and 5S rRNA genes in eight species of Astyanax (Pisces, Characiformes) with different diploid numbers: syntenic conservation of repetitive genes.

    Science.gov (United States)

    Piscor, Diovani; Parise-Maltempi, Patricia Pasquali

    2016-03-01

    The genus Astyanax is widely distributed from the southern United States to northern Patagonia, Argentina. While cytogenetic studies have been performed for this genus, little is known about the histone gene families. The aim of this study was to examine the chromosomal relationships among the different species of Astyanax. The chromosomal locations of the 5S rRNA and H3 histone genes were determined in A. abramis, A. asuncionensis, A. altiparanae, A. bockmanni, A. eigenmanniorum, A. mexicanus (all 2n = 50), A. fasciatus (2n = 46), and A. schubarti (2n = 36). All eight species exhibited H3 histone clusters on two chromosome pairs. In six species (A. abramis, A. asuncionensis, A. altiparanae, A. bockmanni, A. eigenmanniorum, and A. fasciatus), syntenic clusters of H3 histone and 5S rDNA were observed on metacentric (m) or submetacentric (sm) chromosomes. In seven species, clusters of 5S rDNA sequences were located on one or two chromosome pairs. In A. mexicanus, 5S rDNA clusters were located on four chromosome pairs. This study demonstrates that H3 histone clusters are conserved on two chromosome pairs in the genus Astyanax, and specific chromosomal features may contribute to the genomic organization of the H3 histone and 5S rRNA genes.

  17. Cytogenetic and morphometric analysis in the species Astyanax altiparanae Garutti & Britski, 2000 (Teleostei, Characidae) from the Iguatemi River Basin, Brazil.

    Science.gov (United States)

    Fernandes, Carlos Alexandre; Da Rocha, Rafael Henrique; Bailly, Dayani; Guterres, Zaira Da Rosa; Alves, Diandra Soares; Martins-Santos, Isabel Cristina

    2014-01-01

    The genus Astyanax is relatively common and encompasses various similar taxa forming a highly complex group that is difficult to precisely delimit. The present study aims to analyze cytogenetically and morphologically specimens of A. altiparanae belonging to distinct populations of the Iguatemi River Basin, Mato Grosso do Sul State, Brazil, for a better understanding of the evolutionary processes in this fish group. This study analysed 32 specimens of Astyanax altiparanae from Iguatemi River basin, MS, Brazil: 24 from the Agua Boa stream and 8 from the Santa Maria stream. All specimens showed a diploid number equal to 50 chromosomes with differences in the karyotypic formula and types of chromosomes bearing the NOR between the two localities. The constitutive heterochromatin showed interstitial markings evident in the region of some chromosomes in both populations. In the morphometric analysis, the first three axes were retained for interpretation which together explained 81% of variance, showing morphometric distinction between populations. Chromosomal and morphometric data obtained may be useful for taxonomic and phylogenetic studies in this group of fish.

  18. Evolution of Space Dependent Growth in the Teleost Astyanax mexicanus

    OpenAIRE

    2012-01-01

    The relationship between growth rate and environmental space is an unresolved issue in teleosts. While it is known from aquaculture studies that stocking density has a negative relationship to growth, the underlying mechanisms have not been elucidated, primarily because the growth rate of populations rather than individual fish were the subject of all previous studies. Here we investigate this problem in the teleost Astyanax mexicanus, which consists of a sighted surface-dwelling form (surfac...

  19. Ecomorphology of Astyanax species in streams with different substrates

    Directory of Open Access Journals (Sweden)

    Marcela A. Souza

    2014-02-01

    Full Text Available In the present study, we assessed the ecomorphology of two species of Astyanax in streams with different substrates found in the Rio São Francisco Basin. The dominant substrate of each stream was defined as either "fine" (0 to 2 mm, "gravel" (2 to 250 mm, "rock" (> 250 mm, or "leaf bank". We analyzed a total of 22 ecomorphological attributes of Astyanax intermedius Eigenmann, 1908 (127 individuals and Astyanax rivularis (Lütken, 1875 (238 individuals adults. We detected significant ecomorphological differences between the populations of A. rivularis and A. intermedius from habitats with different types of substrates. However, the two species did not show the same morphological differences depending on the type of substrate. These results confirmed the hypothesis that individuals from environments with different characteristics may have different ecomorphological patterns. Knowing that morphology is associated with habitat use and available resources, the loss of a resource or a modification in the environment may directly affect the permanence of a species, leading to a loss of morphologic diversity.

  20. Chapter 8. Evolution and development in the cavefish Astyanax.

    Science.gov (United States)

    Jeffery, William R

    2009-01-01

    The teleost Astyanax mexicanus is a single species consisting of two radically different forms: a sighted pigmented surface-dwelling form (surface fish) and a blind depigmented cave-dwelling form (cavefish). The two forms of Astyanax have favorable attributes, including descent from a common ancestor, ease of laboratory culture, and the ability to perform genetic analysis, permitting their use as a model system to explore questions in evolution and development. Here, we review current research on the molecular, cellular, and developmental mechanisms underlying the loss of eyes and pigmentation in Astyanax cavefish. Although functional eyes are lacking in adults, cavefish embryos begin to develop eye primordia, which subsequently degenerate. The major cause of eye degeneration appears to be apoptotic cell death of the lens, which prevents the growth of other optic tissues, including the retina. Ultimately, the loss of the eye is the cause of craniofacial differences between cavefish and surface fish. Lens apoptosis is induced by enhanced activity of the Hedgehog signaling system along the cavefish embryonic midline. The absence of melanin pigmentation in cavefish is due to a block in the ability of undifferentiated melanoblasts to accumulate L-tyrosine, the precursor of L-DOPA and melanin, in melanosomes. Genetic analysis has shown that this defect is caused by a hypomorphic mutation in the p/oca2 gene encoding an integral melanosomal membrane protein. We discuss how current studies of eye and pigment regression have revealed some of the mechanisms in which cavefish development has been changed during evolution.

  1. Chromosome mapping of H1 histone and 5S rRNA gene clusters in three species of Astyanax (Teleostei, Characiformes).

    Science.gov (United States)

    Hashimoto, D T; Ferguson-Smith, M A; Rens, W; Foresti, F; Porto-Foresti, F

    2011-01-01

    We report here on the physical mapping of the H1 histone genes (hisDNA) and the 5S ribosomal DNA (rDNA) in 3 Neotropical fish species of the genus Astyanax(A. altiparanae, A. bockmanni and A. fasciatus) and the comparative analysis of the chromosomes bearing these genes. Nucleotide analyses by sequencing of both genes were also performed. The distribution of the H1 histone genes was more conserved than that of the rRNA genes, since these were always located in the pericentromeric regions of 2 chromosome pairs. 5S rDNA was found on one of the pairs that presented an H1 histone cluster; this seems to be a conserved chromosomal feature of the genus Astyanax. In addition, individuals of A. bockmanni and A. fasciatus showed clusters of 5S rDNA on 1 pair of acrocentric chromosomes, not found in A. altiparanae. The results obtained by chromosome mapping as well as by sequencing of both genes showed that A.bockmanni is more closely related to A. fasciatus than to A. altiparanae. The results allow the characterization of cytogenetic markers for improved elucidation of the processes involved in karyotype differentiation of fish genomes. Copyright © 2011 S. Karger AG, Basel.

  2. Baird's tapir density in high elevation forests of the Talamanca region of Costa Rica.

    Science.gov (United States)

    González-Maya, José F; Schipper, Jan; Polidoro, Beth; Hoepker, Annelie; Zárrate-Charry, Diego; Belant, Jerrold L

    2012-12-01

    Baird's tapir (Tapirus bairdii) is currently endangered throughout its neotropical range with an expected population decline >50% in the next 30 years. We present the first density estimation of Baird's tapir for the Talamanca mountains of Costa Rica, and one of the first for the country. Ten stations with paired cameras were established in Valle del Silencio within Parque Internacional La Amistad (PILA). Seventy-seven tapir pictures of 15 individuals comprising 25 capture-recapture events were analyzed using mark-recapture techniques. The 100% minimum convex polygon of the sampled area was 5.7 km(2) and the effective sampled area using half mean maximum distances moved by tapirs was 7.16 km(2) . We estimated a tapir density of 2.93 individuals/km(2) which represents the highest density reported for this species. Intermountain valleys can represent unique and important habitats for large mammal species. However, the extent of isolation of this population, potentially constrained by steep slopes of the cordillera, remains unknown. Further genetic and movement studies are required to understand meta-population dynamics and connectivity between lowland and highland areas for Baird's tapir conservation in Costa Rica. © 2012 Wiley Publishing Asia Pty Ltd, ISZS and IOZ/CAS.

  3. Shadow response in the blind cavefish Astyanax reveals conservation of a functional pineal eye

    OpenAIRE

    2008-01-01

    The blind cavefish Astyanax mexicanus undergoes bilateral eye degeneration during embryonic development. Despite the absence of light in the cave environment, cavefish have retained a structurally intact pineal eye. We show here that contrary to visual degeneration in the bilateral eyes, the cavefish pineal eye has conserved the ability to detect light. Larvae of two different Astyanax cavefish populations and the con-specific sighted surface-dwelling form (surface fish) respond similarly to ...

  4. Astyanax scabripinnis (Pisces: Characidae hemoglobins: structure and function

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    G. F. LANDINI

    Full Text Available Electrophoretic patterns of hemoglobins, Root effect, Bohr effect in blood and stripped hemoglobin, Hb-O2 affinity GTP modulation of Astyanax scabripinnis (lambari, caught at three different altitudes in Ribeirão Grande, near Campos do Jordão (São Paulo, are described. All populations showed the same electrophoretic patterns: two cathodal components in starch gel. Normal Bohr effect values were found in these three populations both in blood (phi = -0,11 and stripped hemoglobin (phi = -0,12. Different blood O2 affinities collected in fish of these 3 populations were detected. GTP has a large influence on Hb-O2 binding properties in A. scabripinnis. Stripped hemoglobin shows small Root effect. The addition of triphosphated nucleotides increases this effect. GTP is more effective than ATP on enhancing Root effect. Oxygen availability in water can be the factor responsible for differences found in blood O2 affinity.

  5. Modularity and sense organs in the blind cavefish, Astyanax mexicanus.

    Science.gov (United States)

    Franz-Odendaal, Tamara A; Hall, Brian K

    2006-01-01

    Mexican tetra (Astyanax mexicanus) exist as two morphs: a sighted (surface) form and a blind (cavefish) form. In the cavefish, some modules are lost, such as the eye and pigment modules, whereas others are expanded, such as the taste bud and cranial neuromast modules. We suggest that modularity can be viewed as being nested in a manner similar to Baupläne so that modules express unique sets of genes, cells, and processes. In terms of evolution, we conclude that natural selection can act on any of these hierarchical levels within modules or on all the sensory modules as a whole. We discuss interactions within and between modules with reference to the blind cavefish from both genetic and developmental perspectives. The cavefish represents an illuminating example of module interaction, uncoupling of modules, and module expansion.

  6. Evolution of space dependent growth in the teleost Astyanax mexicanus.

    Directory of Open Access Journals (Sweden)

    Natalya D Gallo

    Full Text Available The relationship between growth rate and environmental space is an unresolved issue in teleosts. While it is known from aquaculture studies that stocking density has a negative relationship to growth, the underlying mechanisms have not been elucidated, primarily because the growth rate of populations rather than individual fish were the subject of all previous studies. Here we investigate this problem in the teleost Astyanax mexicanus, which consists of a sighted surface-dwelling form (surface fish and several blind cave-dwelling (cavefish forms. Surface fish and cavefish are distinguished by living in spatially contrasting environments and therefore are excellent models to study the effects of environmental size on growth. Multiple controlled growth experiments with individual fish raised in confined or unconfined spaces showed that environmental size has a major impact on growth rate in surface fish, a trait we have termed space dependent growth (SDG. In contrast, SDG has regressed to different degrees in the Pachón and Tinaja populations of cavefish. Mating experiments between surface and Pachón cavefish show that SDG is inherited as a dominant trait and is controlled by multiple genetic factors. Despite its regression in blind cavefish, SDG is not affected when sighted surface fish are raised in darkness, indicating that vision is not required to perceive and react to environmental space. Analysis of plasma cortisol levels showed that an elevation above basal levels occurred soon after surface fish were exposed to confined space. This initial cortisol peak was absent in Pachón cavefish, suggesting that the effects of confined space on growth may be mediated partly through a stress response. We conclude that Astyanax reacts to confined spaces by exhibiting SDG, which has a genetic component and shows evolutionary regression during adaptation of cavefish to confined environments.

  7. Evolution of space dependent growth in the teleost Astyanax mexicanus.

    Science.gov (United States)

    Gallo, Natalya D; Jeffery, William R

    2012-01-01

    The relationship between growth rate and environmental space is an unresolved issue in teleosts. While it is known from aquaculture studies that stocking density has a negative relationship to growth, the underlying mechanisms have not been elucidated, primarily because the growth rate of populations rather than individual fish were the subject of all previous studies. Here we investigate this problem in the teleost Astyanax mexicanus, which consists of a sighted surface-dwelling form (surface fish) and several blind cave-dwelling (cavefish) forms. Surface fish and cavefish are distinguished by living in spatially contrasting environments and therefore are excellent models to study the effects of environmental size on growth. Multiple controlled growth experiments with individual fish raised in confined or unconfined spaces showed that environmental size has a major impact on growth rate in surface fish, a trait we have termed space dependent growth (SDG). In contrast, SDG has regressed to different degrees in the Pachón and Tinaja populations of cavefish. Mating experiments between surface and Pachón cavefish show that SDG is inherited as a dominant trait and is controlled by multiple genetic factors. Despite its regression in blind cavefish, SDG is not affected when sighted surface fish are raised in darkness, indicating that vision is not required to perceive and react to environmental space. Analysis of plasma cortisol levels showed that an elevation above basal levels occurred soon after surface fish were exposed to confined space. This initial cortisol peak was absent in Pachón cavefish, suggesting that the effects of confined space on growth may be mediated partly through a stress response. We conclude that Astyanax reacts to confined spaces by exhibiting SDG, which has a genetic component and shows evolutionary regression during adaptation of cavefish to confined environments.

  8. Microanatomy of the terminal air spaces of Baird's beaked whale (Berardius bairdii) lungs.

    Science.gov (United States)

    Ninomiya, Hiroyoshi; Inomata, Tomo; Shirouzu, Hiroshi; Katsumata, Etsuko

    2005-05-01

    The terminal airways and microvasculature of five adult Baird's beaked whales (Berardius bairdii) lungs have been examined by means of light and scanning electron microscopy of corrosion casts. The respiratory system of the Baird's beaked whale has various anatomical features which allow them to attain great depths and remain submerged for long periods. The whale lung has components including hyaline cartilage and smooth muscle throughout, reaching as far as the peripheral bronchi, sphincters surrounding the terminal bronchioles, the thick alveolar septa with a connective tissue core and a bi-layer capillary bed, and a distinctive venous plexus of the pulmonary veins. The well-developed venous plexuses of the pulmonary vein are found in the interlobular connective tissue, and around the airways and pulmonary arteries with close apposition. The hyaline cartilage throughout the airways may increase the effective dead air space that accommodates most of the air forced from the collapsed alveoli during a dive. The sphincter might serve as a cock for regulating buoyancy and for trapping air in the alveoli to prevent their complete collapse and a sucking in of alveolar tissue as the dive becomes deeper. The venous plexuses might be for pooling the large volume of blood in the lung to conserve oxygen for deep and prolonged diving.

  9. Genetic and biogeographical relationships among species of Astyanax (Teleostei, Characidae) in Brazilian river basins.

    Science.gov (United States)

    Mello, R; Maniglia, T C; Prioli, S M A P; Prioli, A J

    2015-11-30

    The genetic relationships among 17 species of Astyanax from the Iguaçu River and adjacent river basins in Brazil were examined using nucleotide sequences of the mitochondrial cytochrome b gene (cytb). Congruent trees were constructed using neighbor-joining, maximum-likelihood, and Bayesian methods. The resulting clades suggest that at least three major groups share similar origins with the endemic species of the Iguaçu River. The results indicate that Astyanax is polyphyletic in this location, which suggests that Astyanax did not diversify from a single ancestral group that was isolated when the Iguaçu River basin formed. Astyanax bifasciatus shares an origin with some species of the altiparanae-bimaculatus complex, while A. minor originated from the same group as A. aff. paranae, A. fasciatus, and A. bockmanni. The third group includes A. dissimilis, Astyanax sp F, and A. serratus that are endemic species to the Iguaçu River basin. Geological and hydrological events that influenced the biogeographical patterns of these species are discussed.

  10. Commentary on Baird, J., Andrich, D., Hopfenbeck, T. N. and Stobart, G., "Assessment and Learning: Fields Apart"

    Science.gov (United States)

    Scharaschkin, Alex

    2017-01-01

    This issue's featured article, "Assessment and Learning: Fields Apart" (Baird, Andrich, Hopfenbeck, and Stobart 2017) raises issues that are of basic importance for the disciplines of assessment and teaching and learning theory. In this commentary, Alex Scharaschkin restricts his remarks to a few areas. He considers the idea of a…

  11. Essai comparé de traitement de nématodes de poulet au "Sodivermyl"-Baird et à l'écorce de Combretum Sp. (Combretacée

    Directory of Open Access Journals (Sweden)

    Tchoumboue, J.

    1996-01-01

    Full Text Available Comparative Effects of "Sodivermyl" Baird and the Bark of Combretum sp. in the Treatment of Chicken Nematods (in French. In order to determine the parasiticidal effects of the bark of a creeper of the genus Combretum as compared to tetramisole, 77 chickens of local breed naturally infected with various parasites and coming from peasant farms around Dschang, Cameroon, were divided into 3 groups : T0 (control, Tf (treated with tetramisole, and T2 (treated with Combretum sp. 's Bark. The efficacy rates of both treatments T1 and T2 were generally similar : Capillaria (94 % and 92 %, respectively, Heterakis (100 % and 90 %, Ascaridia (100 % and 70 %. These results are interesting enough to justify further studies under controlled conditions on the nematodicidal properties of Combretum sp. 's Bark.

  12. Plasticity in the diet of Astyanax taeniatus in a coastal stream from south-east Brazil

    Directory of Open Access Journals (Sweden)

    LR. Manna

    Full Text Available In this work we aimed to characterise the diet of Astyanax taeniatus (Jenyns 1842 (Characiformes, Characidae along the Mato Grosso stream and we hypothesised that the diet of this species would vary according to spatial, seasonal and ontogenetic differences. Specimens were collected every second month at three sites with different physical attributes. The feeding habits of 651 specimens were analysed using the Alimentary Index (IAi. Analysis of the diet showed an effect of spatial, temporal and ontogenetic factors. Vegetal allochthonous items were more important in the diet of Astyanax taeniatus in upstream sites while animal autochthonous items were more important downstream. Ontogenetic differences in the diet were significant only in upstream sites, where adults consumed a greater amount of vegetal matter than juveniles. These results reinforce the idea that Astyanax species are opportunistic and show trophic plasticity.

  13. Functional morphology of the tetra fish Astyanax lacustris differs between divergent habitats in the Pantanal wetlands.

    Science.gov (United States)

    Costa-Pereira, R; Araújo, M S; Paiva, F; Tavares, L E R

    2016-08-01

    This study investigated whether the body morphology of the tetra fish Astyanax lacustris (previously Astyanax asuncionensis) varied between populations inhabiting one lagoon (a lentic, shallow environment, with great habitat complexity created by aquatic macrophytes) and an adjacent river (a deeper, lotic environment where aquatic macrophytes are scarce) in a seasonally flooded wetland, despite population mixing during the wet season. Morphological differences matched a priori predictions of the theory relating functional body morphology and swimming performance in fishes between lagoon and river habitats. Observed morphological variation could have resulted from adaptive habitat choice by tetras, predation by piscivores and adaptive phenotypic plasticity during development.

  14. An etiopathogenesis analysis of sudden death cause for Baird' s tapir%猝死中美貘死亡原因分析

    Institute of Scientific and Technical Information of China (English)

    刘燕; 郑常明; 李林海; 阎鹤; 丁楠; 赵京; 张成林; 张海杰; 杨明海

    2012-01-01

    November 2011, a two-year-old Baird's tapir (Tapirus bairdii) suddenly died in the Beijing Zoo. This paper records the pathogen testing results. Cultures showed that the organs of Baird' s tapir did not contain any bacteria, but there were two main bacteria Clostridium perfringens and Streptococcus bovis, in the intestinal contents. The serotype of the C. perfringens was found to be type A by multiplex PCR method. Clinical characteristics and autopsy pathology ultimately determined that C. perfringens type A was the primary pathogen in the death of the Baird' s tapir, The role of S. bovis was minor.

  15. Microvasculature in the terminal air spaces of the lungs of the Baird's beaked whale (Berardius bairdii).

    Science.gov (United States)

    Ninomiya, Hiroyoshi; Inomata, Tomo; Shirouzu, Hiroshi

    2004-12-01

    Lungs were obtained from five adult Baird's beaked whales (Berardius bairdii) and examined by means of light microscopy and scanning electron microscopy of corrosion casts. The alveolar septa of these whales are thick with a connective tissue core and a bi-layer capillary bed. A double capillary network is regularly found in the alveolar duct and alveolar septa. Occasionally, septa adjacent to alveoli and alveoli themselves show only a single capillary layer. The distance between the two capillary layers has a tendency to decrease toward the end of airspaces, suggesting an end result of capillary fusion. Vascular replicas of venous vessels have annular furrows at regular intervals of 50 to 100 microm, which are caused by focal aggregations of collagen fibers circularly oriented and located immediately underneath the endothelium. The first valves appear in the collecting venules gathering alveolar capillaries. These valves are quite characteristic of flap-, funnel-and/or chimney like structures.

  16. Em busca de uma ética ambiental: as perspectivas e Baird Callicott e Paul Taylor

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    Tânia Aparecida Kuhnen

    2012-05-01

    Full Text Available http://dx.doi.org/10.5007/1677-2954.2008v7n3p19O tema deste artigo é a ética ambiental e, mais especificamente, as propostas éticas de Baird Callicott e Paul Taylor, formuladas na tentaiva de expandir a comunidade moral. Enquanto Calliott defende uma perspectiva holista de ética ambiental, na qual o valor moral da ação depende de quanto ela constribui para o bem da comunidade bioética em sua totalidade, Taylor apresenta como moralmente relevantes as ações que contribuem para promover ou proteger o "bem próprio" de cada entidade viva individual. O objetivo deste estudo é analidar ambas as teorias e indicar qual delas mais se aproxima de um ideal de ética ambiental.

  17. Ejaculate traits and sperm cryopreservation in the endangered Baird's tapir (Tapirus bairdii).

    Science.gov (United States)

    Pukazhenthi, Budhan S; Togna, Gina Della; Padilla, Luis; Smith, Diorene; Sanchez, Carlos; Pelican, Katey; Sanjur, Oris I

    2011-01-01

    There is little information on the reproductive biology of the male Baird's tapir (Tapirus bairdii). In this study, we characterized the ejaculate traits and evaluated the efficacy of 2 cryodiluents on sperm cryosurvival. Ejaculates were assessed for volume, pH, sperm motility, forward progression, osmolality, sperm concentration, sperm morphology, and acrosomal integrity. For cryopreservation, ejaculates with >50% total sperm motility were washed, and sperm pellets were resuspended in either Botu-Crio (CryoVital, Grandau, Germany) or INRA 96 containing 2% egg yolk and 2.5% each of methyl- and dimethylformamide (INRA 96), and they were cryopreserved over liquid nitrogen vapor. Thawed samples were incubated in vitro (25 °C) and evaluated for percent total sperm motility, forward progression, and acrosomal integrity at hourly intervals for 4 hours. Spermic ejaculates were obtained from all males, and the mean seminal volume, sperm concentration per milliliter, percent sperm motility, progressive status, and percent morphologically normal cells were 20.4 ± 4.3 mL, 101.2 ± 24.0 × 10(6)/mL, 46.1% ± 5.0%, 2.9 ± 0.1, and 6.9% ± 1.4%, respectively. There was a positive significant correlation between percent normal sperm and animal age (r = 0.66; P < .004). Cryopreservation in either Botu-Crio or INRA 96 resulted in a decline (P < .05) in percent sperm motility and acrosomal integrity. Sperm forward progression remained unaffected immediately after thawing in INRA 96 but continued to decline over time. These results characterize, for the first time, the ejaculate traits of the tapir; demonstrate that tapir spermatozoa can be cryopreserved in diluents containing amides alone or in combination with glycerol; and provide fundamental information critical for development of assisted reproductive technologies for the Baird's tapir.

  18. Genome editing using TALENs in blind Mexican Cavefish, Astyanax mexicanus.

    Directory of Open Access Journals (Sweden)

    Li Ma

    Full Text Available Astyanax mexicanus, a teleost fish that exists in a river-dwelling surface form and multiple cave-dwelling forms, is an excellent system for studying the genetic basis of evolution. Cavefish populations, which independently evolved from surface fish ancestors multiple times, have evolved a number of morphological and behavioral traits. Quantitative trait loci (QTL analyses have been performed to identify the genetic basis of many of these traits. These studies, combined with recent sequencing of the genome, provide a unique opportunity to identify candidate genes for these cave-specific traits. However, tools to test the requirement of these genes must be established to evaluate the role of candidate genes in generating cave-specific traits. To address this need, we designed transcription activator-like effector nucleases (TALENs to target two genes that contain coding changes in cavefish relative to surface fish and map to the same location as QTL for pigmentation, oculocutaneous albinism 2 (oca2 and melanocortin 1 receptor (mc1r. We found that surface fish genes can be mutated using this method. TALEN-induced mutations in oca2 result in mosaic loss of melanin pigmentation visible as albino patches in F0 founder fish, suggesting biallelic gene mutations in F0s and allowing us to evaluate the role of this gene in pigmentation. The pigment cells in the albino patches can produce melanin upon treatment with L-DOPA, behaving similarly to pigment cells in albino cavefish and providing additional evidence that oca2 is the gene within the QTL responsible for albinism in cavefish. This technology has the potential to introduce a powerful tool for studying the role of candidate genes responsible for the evolution of cavefish traits.

  19. Genome editing using TALENs in blind Mexican Cavefish, Astyanax mexicanus.

    Science.gov (United States)

    Ma, Li; Jeffery, William R; Essner, Jeffrey J; Kowalko, Johanna E

    2015-01-01

    Astyanax mexicanus, a teleost fish that exists in a river-dwelling surface form and multiple cave-dwelling forms, is an excellent system for studying the genetic basis of evolution. Cavefish populations, which independently evolved from surface fish ancestors multiple times, have evolved a number of morphological and behavioral traits. Quantitative trait loci (QTL) analyses have been performed to identify the genetic basis of many of these traits. These studies, combined with recent sequencing of the genome, provide a unique opportunity to identify candidate genes for these cave-specific traits. However, tools to test the requirement of these genes must be established to evaluate the role of candidate genes in generating cave-specific traits. To address this need, we designed transcription activator-like effector nucleases (TALENs) to target two genes that contain coding changes in cavefish relative to surface fish and map to the same location as QTL for pigmentation, oculocutaneous albinism 2 (oca2) and melanocortin 1 receptor (mc1r). We found that surface fish genes can be mutated using this method. TALEN-induced mutations in oca2 result in mosaic loss of melanin pigmentation visible as albino patches in F0 founder fish, suggesting biallelic gene mutations in F0s and allowing us to evaluate the role of this gene in pigmentation. The pigment cells in the albino patches can produce melanin upon treatment with L-DOPA, behaving similarly to pigment cells in albino cavefish and providing additional evidence that oca2 is the gene within the QTL responsible for albinism in cavefish. This technology has the potential to introduce a powerful tool for studying the role of candidate genes responsible for the evolution of cavefish traits.

  20. Quantitative genetic analysis of retinal degeneration in the blind cavefish Astyanax mexicanus.

    Directory of Open Access Journals (Sweden)

    Kelly E O'Quin

    Full Text Available The retina is the light-sensitive tissue of the eye that facilitates vision. Mutations within genes affecting eye development and retinal function cause a host of degenerative visual diseases, including retinitis pigmentosa and anophthalmia/microphthalmia. The characin fish Astyanax mexicanus includes both eyed (surface fish and eyeless (cavefish morphs that initially develop eyes with normal retina; however, early in development, the eyes of cavefish degenerate. Since both surface and cave morphs are members of the same species, they serve as excellent evolutionary mutant models with which to identify genes causing retinal degeneration. In this study, we crossed the eyed and eyeless forms of A. mexicanus and quantified the thickness of individual retinal layers among 115 F(2 hybrid progeny. We used next generation sequencing (RAD-seq and microsatellite mapping to construct a dense genetic map of the Astyanax genome, scan for quantitative trait loci (QTL affecting retinal thickness, and identify candidate genes within these QTL regions. The map we constructed for Astyanax includes nearly 700 markers assembled into 25 linkage groups. Based on our scans with this map, we identified four QTL, one each associated with the thickness of the ganglion, inner nuclear, outer plexiform, and outer nuclear layers of the retina. For all but one QTL, cavefish alleles resulted in a clear reduction in the thickness of the affected layer. Comparative mapping of genetic markers within each QTL revealed that each QTL corresponds to an approximately 35 Mb region of the zebrafish genome. Within each region, we identified several candidate genes associated with the function of each affected retinal layer. Our study is the first to examine Astyanax retinal degeneration in the context of QTL mapping. The regions we identify serve as a starting point for future studies on the genetics of retinal degeneration and eye disease using the evolutionary mutant model Astyanax.

  1. Bosmina (Eubosmina coregoni Baird, 1857 (Crustacea, Branchiopoda, Anomopoda: New planktonic invader in the Iberian peninsula

    Directory of Open Access Journals (Sweden)

    Geraldes, A. M.

    2014-12-01

    Full Text Available Bosmina (Eubosmina coregoni Baird, 1857 has been recorded for the first time in the Iberian Peninsula. It is a planktonic cladoceran widely distributed in the Holarctic region which was never previously referred in the Iberian Peninsula in spite of the numerous and intensive studies on freshwater planktonic fauna in this geographic area in the last three decades. The species appeared in five reservoirs located in the Northwest quadrant. Excepting Valdecañas reservoir, which can be considered eutrophic, the others (Bárcena, Peares, Belesar and Aguieira were classified as meso-eutrophic. The only morphotype found corresponds to Bosmina (Eubosmina coregoni ssp. coregoni. The maximum abundance of this species occurred during the winter period. It is plausible to consider that waterfowl migration and the presence of recreational boats might be the dispersion vector of this species in Iberian Peninsula.Se cita Bosmina (Eubosmina coregoni Baird, 1857 por vez primera en la península ibérica. Se trata de un cladócero planctónico ampliamente distribuido en la región holártica, que no había sido previamente referido en la península ibérica a pesar de los numerosos e intensivos estudios sobre la fauna planctónica de agua dulce realizados durante las últimas tres décadas en este ámbito geográfico. La especie ha aparecido en cinco embalses situados en el cuadrante noroccidental. Con excepción del Embalse de Valdecañas, que se puede considerar eutrófico, los restantes (Bárcena, Peares, Belesar y Aguieira fueron clasificados como mesoeutróficos. El único morfotipo encontrado corresponde a Bosmina (Eubosmina coregoni ssp. coregoni. La abundancia máxima de la especie ocurrió durante el período del invierno. Es plausible considerar que las aves acuáticas y la presencia de embarcaciones de recreo pudieron ser un vector importante de la dispersión de esta especie en la península ibérica.

  2. Acoustic and foraging behavior of a Baird's beaked whale, Berardius bairdii, exposed to simulated sonar.

    Science.gov (United States)

    Stimpert, A K; DeRuiter, S L; Southall, B L; Moretti, D J; Falcone, E A; Goldbogen, J A; Friedlaender, A; Schorr, G S; Calambokidis, J

    2014-11-13

    Beaked whales are hypothesized to be particularly sensitive to anthropogenic noise, based on previous strandings and limited experimental and observational data. However, few species have been studied in detail. We describe the underwater behavior of a Baird's beaked whale (Berardius bairdii) from the first deployment of a multi-sensor acoustic tag on this species. The animal exhibited shallow (23 ± 15 m max depth), intermediate (324 ± 49 m), and deep (1138 ± 243 m) dives. Echolocation clicks were produced with a mean inter-click interval of approximately 300 ms and peak frequency of 25 kHz. Two deep dives included presumed foraging behavior, with echolocation pulsed sounds (presumed prey capture attempts) associated with increased maneuvering, and sustained inverted swimming during the bottom phase of the dive. A controlled exposure to simulated mid-frequency active sonar (3.5-4 kHz) was conducted 4 hours after tag deployment, and within 3 minutes of exposure onset, the tagged whale increased swim speed and body movement, and continued to show unusual dive behavior for each of its next three dives, one of each type. These are the first data on the acoustic foraging behavior in this largest beaked whale species, and the first experimental demonstration of a response to simulated sonar.

  3. The coexistence of Baird's tapir (Tapirus bairdii) and indigenous hunters in northeastern Honduras.

    Science.gov (United States)

    Dunn, Marc; Estrada, Nereyda; Smith, Derek A

    2012-12-01

    The Baird's tapir (Tapirus bairdii) is a popular game species throughout Central America, particularly among indigenous populations, and is currently endangered. Research on Miskitu hunting was conducted over 4 months in a remote region in northeastern Honduras that overlaps with the Río Plátano Biosphere Reserve. The hunting zone was mapped together with hunters and interviews were conducted with elders and other community members about tapir hunting. Results show that tapir harvesting is targeted toward specific habitats at specific times of year. Harvest rates for one year suggest that tapir hunting in the area exceeds estimates of maximum sustainable production. Nevertheless, field surveys reveal the presence of tapir within 1 km of the community, and its harvest tends to be nearby, in both forested and agricultural landscapes, suggesting that the animal has not been depleted in the area. It appears that the existence of forest areas adjacent to the hunting zone that do not experience hunting, together with the anthropogenic habitats created through shifting cultivation, are factors that help explain the presence of tapirs in the area. The article concludes with a discussion regarding the potential positive role of indigenous hunters in tapir conservation throughout its distribution range.

  4. Chromosome studies of Astyanax jacuhiensis Cope, 1894 (Characidae) from the Tramandai River Basin, Brazil, using in situ hybridization with the 18S rDNA probe, DAPI and CMA3 staining.

    Science.gov (United States)

    da Silva, Laura Lahr Lourenço; Giuliano-Caetano, Lucia; Dias, Ana Lúcia

    2012-01-01

    The genus Astyanax comprises 86 species of fish distributed in Brazilian river basins and is considered of the Incertae sedis group within the family Characidae. This study presents an analysis of 12 specimens of Astyanax jacuhiensis from the Tramandai River Basin, RS Brazil: 6 from the Maquiné River and 6 from the Quadros Lagoon. All specimens showed a diploid number equal to 50 chromosomes with different karyotypic formula between the two localities. The population from the Maquiné River showed 10m+26sm+6st+8a (FN=92). Fish from the Quadros Lagoon showed 12m+20sm+6st+12a (FN=88). AgNORs were evidenced in the short arm of one acrocentric chromosome pair in both populations, confirmed by FISH with the 18S rDNA probe. CMA3 fluorochrome corresponded with the AgNOR sites, while DAPI staining was negative in these regions. C banding revealed that heterochromatin was weakly distributed, mainly in the pericentromeric and terminal regions in most chromosomes. Analyses of male gonadal tissue were conducted with the objective of characterizing the meiotic chromosome behavior in A. jacuhiensis. The following stages were evidenced: spermatogonial with 50 chromosomes, pachytene and metaphase I with 25 bivalents, and metaphase II with 25 chromosomes, thus confirming the diploid number of the species. Chromosomal abnormalities were not observed. This study shows preliminary data on A. jacuhiensis from the Tramandai River Basin, contributing with more chromosomal information for this group of fish.

  5. The lens controls cell survival in the retina: evidence from the blind cavefish Astyanax

    OpenAIRE

    2007-01-01

    The lens influences retinal growth and differentiation during vertebrate eye development but the mechanisms are not understood. The role of the lens in retinal growth and development was studied in the teleost Astyanax mexicanus, which has eyed surface-dwelling (surface fish) and blind cave-dwelling (cavefish) forms. A lens and laminated retina initially develop in cavefish embryos, but the lens dies by apoptosis. The cavefish retina is subsequently disorganized, apoptotic cells appear, the p...

  6. Differentially expressed genes identified by cross-species microarray in the blind cavefish Astyanax

    OpenAIRE

    2009-01-01

    Changes in gene expression were examined by microarray analysis during development of the eyed surface dwelling (surface fish) and blind cave-dwelling (cavefish) forms of the teleost Astyanax mexicanus De Filippi, 1853. The cross-species microarray used surface and cavefish RNA hybridized to a DNA chip prepared from a closely related species, the zebrafish Danio rerio Hamilton, 1822. We identified a total of 67 differentially expressed probe sets at three days post-fertilization: six upregula...

  7. Comparative cytogenetics among populations of Astyanax altiparanae (Characiformes, Characidae, Incertae sedis)

    Science.gov (United States)

    2009-01-01

    Cytogenetic data are presented for Astyanax altiparanae populations from three Brazilian hydrographic systems. The chromosomal data obtained in A. altiparanae support the hypothesis of diploid number conservation. However, small differences in the karyotype formula and number of nucleolar organizer regions were observed in these populations. The apparent karyotypical similarity among the studied populations strongly suggests a close relationship among them with some chromosomal divergences due to gene flow restriction. PMID:21637456

  8. Contrasting feeding habits of post-larval and adult Astyanax cavefish

    OpenAIRE

    2017-01-01

    The subterranean environment is often described as "extreme" and food poor. Laboratory experiments have shown that blind Mexican tetra Astyanax mexicanus (De Filippi, 1853) cavefish are better at finding food in the dark than surface fish. Several morphological and behavioural attributes that could foster this obvious adaptive response to cave environments have been described. Nonetheless, it is currently unknown what young cavefish actually eat in their natural cave environment. Our results ...

  9. Microsatellite Organization in the B Chromosome and A Chromosome Complement in Astyanax (Characiformes, Characidae) Species.

    Science.gov (United States)

    Piscor, Diovani; Parise-Maltempi, Patricia P

    2016-01-01

    The organization of microsatellites in B and sex chromosomes has been linked to chromosomal evolution in a number of animal groups. Here, the chromosomal organizations of (CA)15, (GA)15, (CG)15, (GACA)4, and (GATA)8 microsatellites were examined in several Astyanax species with different diploid numbers: Astyanax mexicanus (2n = 50 + 1 B chromosome), A. altiparanae (2n = 50), A. marionae (2n = 48), A. fasciatus (2n = 46), and A. schubarti (2n = 36). The (CA)15 and (GA)15 microsatellites were dispersed across the chromosomes of A. altiparanae and A. fasciatus but were also observed as clusters (CA and GA for A. altiparanae, and CA for A. fasciatus). In A. marionae and A. schubarti, the (CA)15 and (GA)15 microsatellites were dispersed but were also observed as clustered signals and coincident with heterochromatic regions. In all 4 of these species, the (CG)15 and (GACA)4 microsatellites were dispersed across chromosomes, and the (GATA)8 microsatellite was co-localized with 5S rDNA. In A. mexicanus, the (CA)15, (GA)15, (CG)15, (GATA)8, and (GACA)4 microsatellites were weakly detected and dispersed across the chromosomes of the A complement. On the B chromosome, signals for the different microsatellites were weak, strong, absent, weak, and absent, respectively. The distribution of microsatellites and the locational relationship between microsatellites and 5S rDNA are discussed, and a possible evolutionary pathway is proposed for microsatellites in Astyanax. © 2016 S. Karger AG, Basel.

  10. Human radiation studies: Remembering the early years. Oral history of Donner Lab Administrator Baird G. Whaley, August 15, 1994

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-09-01

    Baird G. Whaley, Donner Lab Administrator, was interviewed by representatives of US DOE Office of Human Radiation Experiments (OHRE). The purpose of the interview was to capture the remembrances of Mr. Whaley concerning what he could relate on activities at the Donner Lab that pertain to the OHRE responsibilities. Following a brief biographical sketch, Mr. Whaley relates his experiences in administration at the LAB including funding activities, staffing concerns, intralaboraory politics, and remembrances of John Lawrence, John Gofman, Cornelius Tobias, Jim Born, Alex Margolis, B.V.A. Low- Beer, and Ed Alpen. Further patient care procedures for Donner Clinic Research Programs were discussed.

  11. Population structure, reproductive biology and feeding of Astyanax fasciatus (Cuvier, 1819 in an Upper Paraná River tributary, Misiones, Argentina Estrutura populacional, biologia reprodutiva e alimentação de Astyanax fasciatus (Cuvier, 1819 em um tributário do alto Rio Paraná, Misiones, Argentina

    Directory of Open Access Journals (Sweden)

    Lourdes María Hirt

    2011-03-01

    Full Text Available AIM: The genus Astyanax is one of the richest in number of species and has one of the widest geographical distributions in Argentina, being possible to find in nine ichthyogeographic ecoregions. The aim of the present work was to analyze the population structure of Astyanax fasciatus in the Garupá Stream, Province of Misiones, Argentina, considering its distribution by size, standard length-total weight relationship and aspects of its reproductive and feeding biology; METHODS: A total of eight experimental fishing campaigns were carried out between September 2002 and May 2004, in agreement with the seasons of the year, using a set of gillnets; RESULTS: We captured a total of 386 individuals, 70% of which in the Middle Basin in autumn and winter. The following gonad stages were identified in both males and females: resting, maturing, mature and spawning. The highest gonadal activity corresponded to the autumn-winter period. The Middle Basin showed the highest capture of individuals in reproductive activity, thus reflecting the seasonality of spawning. The average fecundity was of 4000 oocytes, being 1100 µm the largest oocyte diameter. The mean standard length of the total catch was 99.3 mm and females reached larger sizes than males (P OBJETIVO: O gênero Astyanax é um dos mais ricos em número de espécies e tem uma das maiores distribuições geográficas na Argentina, sendo possível encontrar em nove ecorregiões ictiogeográfica. O objetivo do presente trabalho foi analisar a estrutura populacional de Astyanax fasciatus no arroio Garupá, Província de Misiones, na Argentina, considerando a sua distribuição por tamanho, relação peso-padrão de comprimento total e aspectos de sua biologia reprodutiva e alimentação; MÉTODOS: Foram realizadas oito operações de pescaria sazonais, entre setembro de 2002 e maio de 2004, com uma bateria de redes de emalhar; RESULTADOS: Foram capturados 386 indivíduos, 70% na Bacia Média no outono e

  12. A new species of Henneguya, a gill parasite of Astyanax altiparanae (Pisces: Characidae from Brazil, with comments on histopathology and seasonality

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    Barassa Bianca

    2003-01-01

    Full Text Available A new species of Myxosporea, Henneguya chydadea, is described parasitizing the gills of Astyanax altiparanae collected from a lake on Rio das Pedras farm near Campinas, state of São Paulo, Brazil. Of the fish examined, 88.3% had gills parasitized by myxosporeans. The prevalence of the parasite ranged from 80% in the spring and fall, 93% in the summer and 100% in the winter. The parasite induced the formation of white, oval-shaped cysts measuring 40-64 µm x 64-80 µm which deformed the gill lamellae, compressed the capillaries, and caused retraction of the neighboring lamellae. The mature spores were elongated and had two identical, parallel elongate polar capsules. Each capsule contained a polar filament with 9-10 turns. There was no mucous envelope or iodinophilous vacuole. Morphometric differences between this parasite and other species of the genus Henneguya indicated, that he parasite observed in A. altiparanae is a new species. This is the first report of a myxosporeanparasitizing A. altiparanae.

  13. New Astyanax from the upper rio Tapajós drainage, Central Brazil (Characiformes: Characidae

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    Vinicius A. Bertaco

    2007-03-01

    Full Text Available Astyanax utiariti, new species, is described from the upper rio Tapajós drainage, Mato Grosso, Brazil. Astyanax utiariti has a horizontally oval black humeral spot, a lozenge-shaped caudal-peduncle spot, continuing to the tip of the middle caudal-fin rays, and two brown bars in the humeral region that allows its inclusion in the A. bimaculatus species group. It also possesses a black stripe extending along midlateral body. The new species is distinguished from its congeners by a reticulate scale pattern, a black longitudinal stripe, toothless maxilla, larger dentary teeth and teeth of the inner row of the premaxilla with five to seven cusps, body depth 33.3-39.9% of standard length (SL, head length (HL 23.9-26.4% of SL, caudal-peduncle depth 12.0-13.4% of SL, orbital diameter 28.5-34.3% of HL, interorbital width 32.7-38.4% of HL, 36-38 perforated scales along the lateral line, and 22-26 branched anal-fin rays.Astyanax utiariti, nova espécie, é descrita da drenagem do alto rio Tapajós, Mato Grosso, Brasil. Astyanax utiariti tem uma mancha umeral preta horizontalmente ovalada, uma mancha losangular preta no pedúnculo caudal continuada até a extremidades dos raios caudais medianos e duas barras marrons na região humeral, que permite sua inclusão no grupo de espécies A. bimaculatus. Também possui uma faixa preta estendida ao longo do meio do corpo. A nova espécie distingue-se de suas congêneres pelo padrão reticulado nas escamas, uma faixa preta longitudinal, maxilar sem dentes, dentes maiores do dentário e dentes da série interna do pré-maxilar com cinco a sete cúspides, altura do corpo de 33,3-39,9% do comprimento padrão (CP, comprimento da cabeça (CC de 23,9-26,4% do CP, altura do pedúnculo caudal 12,0-13,4% do CP, diâmetro orbital de 28,5-34,3% do CC, largura interorbital de 32,7-38,4% do CC, 36-38 escamas perfuradas ao longo da linha lateral e 22-26 raios ramificados na nadadeira anal.

  14. Redescription of Astyanax guaporensis Eigenmann, 1911 (Characiformes: Characidae), a small characid from the rio Madeira basin.

    Science.gov (United States)

    Marinho, Manoela M F; Ohara, Willian M

    2013-01-01

    During recent expeditions to several localities in the rio Madeira basin, a poorly known species of Characidae described more than a century ago, Astyanax guaporensis Eigenmann, was collected. The species is herein redescribed based on the type material and many recently collected specimens. The species seems to occur only in the rio Madeira basin, rio Amazonas drainage. The species is mainly recognized among its congeners by having five to nine maxillary teeth, a series of V-shaped marks on the midlateral line of body, and the absence of a black mark on the caudal peduncle.

  15. Diet of Astyanax species (Teleostei, Characidae in an Atlantic Forest River in Southern Brazil

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    Fábio Silveira Vilella

    2002-06-01

    Full Text Available Feeding habits of six species of Astyanax from river Maquiné are described. Fishes were sampled bi-monthly from November/95 to September/96 in two zones of the river. Items were identified, counted and had their abundance estimated according to a semi-quantitative scale. Frequency of occurrence, alimentary importance index (IFI values and a similarity analysis of diets for each species-river zone sample were examined. All the species were considered typically omnivorous, with insects and vegetal matter being the most important items in their diet. These species could act as seed dispersers, particularly for macrophytes. Intra-specific spatial differences were not observed in comparisons of samples from two diferent regions of the river, except for A. fasciatus. The presence of Podostemaceae macrophytes in the mid-course of the river seemed to be important both as an autochthonous food resource and as habitat for several organisms preyed by the Astyanax species.Seis espécies do gênero Astyanax, presentes no rio Maquiné, RS, foram estudadas quanto aos seus hábitos alimentares. Os exemplares foram amostrados bimensalmente de novembro de 1995 a setembro de 1996 nas zonas ritral e potamal do rio. Os itens alimentares foram identificados e quantificados de acordo com uma escala semi-quantitativa de abundância, utilizando-se para análise a frequência de ocorrência e um índice de importância alimentar para cada espécie e zona do rio. Análises multivariadas de agrupamento e ordenação foram utilizadas para comparar as dietas intra e interespecíficas. Todas as espécies foram consideradas onivoras, sendo que os itens mais importantes foram os insetos e restos de vegetais superiores. Sugere-se que as espécies estudadas possam atuar como dispersoras de sementes, particularmente para macrófitas. Diferenças espaciais intraespecíficas não foram encontradas, exceto para A. fasciatus. A presença de Podostemaceae no curso médio do rio parece

  16. The sensitivity of lateral line receptors and their role in the behavior of Mexican blind cavefish (Astyanax mexicanus)

    NARCIS (Netherlands)

    Yoshizawa, Masato; Jeffery, William R; van Netten, Sietse M; McHenry, Matthew J

    2014-01-01

    The characid fish species Astyanax mexicanus offers a classic comparative model for the evolution of sensory systems. Populations of this species evolved in caves and became blind while others remained in streams (i.e. surface fish) and retained a functional visual system. The flow-sensitive lateral

  17. The sensitivity of lateral line receptors and their role in the behavior of Mexican blind cavefish (Astyanax mexicanus)

    NARCIS (Netherlands)

    Yoshizawa, Masato; Jeffery, William R; van Netten, Sietse M; McHenry, Matthew J

    2014-01-01

    The characid fish species Astyanax mexicanus offers a classic comparative model for the evolution of sensory systems. Populations of this species evolved in caves and became blind while others remained in streams (i.e. surface fish) and retained a functional visual system. The flow-sensitive lateral

  18. Ecology and local knowledge of the Baird's tapir (Tapirella bairdii) in the Sierra Madre de Oaxaca, Mexico.

    Science.gov (United States)

    Lavariega Nolasco, Mario César; Briones-Salas, Miguel; Mazas-Teodocio, Amado; Durán-Medina, Elvira

    2016-09-01

    As well as being of global cultural importance (from local tribal folklore to being an iconic species for conservation), the tapir plays an important role in its ecosystem as a herbivore and seed disperser. However, the ecology and ethnozoology of the endangered Baird's tapir in the north of Oaxaca, Mexico is poorly understood. We used camera traps to estimate its relative abundance and density and to describe the activity patterns of the northernmost population of Baird's tapir in the Sierra Madre de Oaxaca. Local knowledge concerning the tapir was also documented, along with the conservation strategies undertaken by the 2 indigenous communities that own the land where the study site is located. Only adult tapirs were photographed, and these were active 14 h per day, but were mainly nocturnal and crepuscular. The estimated relative abundance (12.99 ± 2.24 events/1000 camera days) and density values (0.07-0.24 individuals/km(2) ) were both similar to those found in another site in Mexico located within a protected area. Semi-structured interviews revealed that people have a basic understanding of the eating habits, activity and main predators of the tapir. There were reports of hunting, although not among those respondents who regularly consume bush meat. Thus, the relative abundance and density estimates of tapir at the study site could be related to the favorable condition of the forest and the absence of hunting and consumption of tapir meat. Fortunately, the local people are conducting initiatives promoting the conservation of this ungulate and its habitat that combine to constitute a regional trend of habitat and wildlife protection.

  19. The Stable Concordance Genus

    OpenAIRE

    Kearney, M. Kate

    2013-01-01

    The concordance genus of a knot is the least genus of any knot in its concordance class. Although difficult to compute, it is a useful invariant that highlights the distinction between the three-genus and four-genus. In this paper we define and discuss the stable concordance genus of a knot, which describes the behavior of the concordance genus under connected sum.

  20. Shadow response in the blind cavefish Astyanax reveals conservation of a functional pineal eye.

    Science.gov (United States)

    Yoshizawa, Masato; Jeffery, William R

    2008-02-01

    The blind cavefish Astyanax mexicanus undergoes bilateral eye degeneration during embryonic development. Despite the absence of light in the cave environment, cavefish have retained a structurally intact pineal eye. We show here that contrary to visual degeneration in the bilateral eyes, the cavefish pineal eye has conserved the ability to detect light. Larvae of two different Astyanax cavefish populations and the con-specific sighted surface-dwelling form (surface fish) respond similarly to light dimming by shading the pineal eye. As a response to shading, cavefish larvae swim upward vertically. This behavior resembles that of amphibian tadpoles rather than other teleost larvae, which react to shadows by swimming downward. The shadow response is highest at 1.5-days post-fertilization (d.p.f.), gradually diminishes, and is virtually undetectable by 7.5 d.p.f. The shadow response was substantially reduced after surgical removal of the pineal gland from surface fish or cavefish larvae, indicating that it is based on pineal function. In contrast, removal of one or both bilateral eye primordia did not affect the shadow response. Consistent with its light detecting capacity, immunocytochemical studies indicate that surface fish and cavefish pineal eyes express a rhodopsin-like antigen, which is undetectable in the degenerating bilateral eyes of cavefish larvae. We conclude that light detection by the pineal eye has been conserved in cavefish despite a million or more years of evolution in complete darkness.

  1. Expanded expression of Sonic Hedgehog in Astyanax cavefish: multiple consequences on forebrain development and evolution.

    Science.gov (United States)

    Menuet, Arnaud; Alunni, Alessandro; Joly, Jean-Stéphane; Jeffery, William R; Rétaux, Sylvie

    2007-03-01

    Ventral midline Sonic Hedgehog (Shh) signalling is crucial for growth and patterning of the embryonic forebrain. Here, we report how enhanced Shh midline signalling affects the evolution of telencephalic and diencephalic neuronal patterning in the blind cavefish Astyanax mexicanus, a teleost fish closely related to zebrafish. A comparison between cave- and surface-dwelling forms of Astyanax shows that cavefish display larger Shh expression in all anterior midline domains throughout development. This does not affect global forebrain regional patterning, but has several important consequences on specific regions and neuronal populations. First, we show expanded Nkx2.1a expression and higher levels of cell proliferation in the cavefish basal diencephalon and hypothalamus. Second, we uncover an Nkx2.1b-Lhx6-GABA-positive migratory pathway from the subpallium to the olfactory bulb, which is increased in size in cavefish. Finally, we observe heterochrony and enlarged Lhx7 expression in the cavefish basal forebrain. These specific increases in olfactory and hypothalamic forebrain components are Shh-dependent and therefore place the telencephalic midline organisers in a crucial position to modulate forebrain evolution through developmental events, and to generate diversity in forebrain neuronal patterning.

  2. Cytogenetic data on Astyanax jacuhiensis (Characidae in the lago Guaíba and tributaries, Brazil

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    Rosiley B. Pacheco

    Full Text Available Cytogenetic analyses were performed in Astyanax jacuhiensis from lago Guaíba, Brazil. The diploid number was 50, with a karyotype composed of 8m+30sm+4st+8a chromosomes, FN = 92. The AgNORs were observed in 2 to 5 chromosomes, with intra- and interindividual variation. The sm pair 8 observed always carried NORs on the short arms, presenting size heteromorphism between homologous. Fluorescence in situ hybridization (FISH with an 18S rDNA probe only confirmed the location of ribosomal cistrons in the sm pair 8, and heteromorphism of these regions between the homologous chromosomes. C-banding revealed the occurrence of weak C-positive heterochromatin in the pericentromeric regions of several chromosomes, in addition to more evident bands interstitially located on some chromosome pairs and in the terminal region of the short arms in pair 8. C-banding plus CMA3 revealed light fluorescent signals in different chromosomes of the karyotype, with a strong terminal site in pair 8, indicating the occurrence of several GC-rich heterochromatic regions in this species. Our results provide the first description of the Astyanax jacuhiensis karyotype, showing karyotype similarities when compared to various populations of A. altiparanae and A. bimaculatus, indicating that chromosomal features are very similar for these three species.

  3. Variability and evolutionary implications of repetitive DNA dynamics in genome of Astyanax scabripinnis (Teleostei, Characidae)

    Science.gov (United States)

    Barbosa, Patrícia; Leal, Eliza Viola; da Silva, Maelin; de Almeida, Mara Cristina; Moreira-Filho, Orlando; Artoni, Roberto Ferreira

    2017-01-01

    Abstract DNA sequences of multiple copies help in understanding evolutionary mechanisms, genomic structures and karyotype differentiation. The current study investigates the organization and distribution of different repetitive DNA in the standard complement and B chromosomes in Astyanax scabripinnis (Jenyns, 1842) chromosomes from three allopatric populations in Campos do Jordão region, São Paulo State, Brazil. The location of microsatellite sequences showed different chromosome distribution between Lavrinha Farm Stream (LFS) and Lake of Pedalinho (LP) populations. However, the karyotype of these populations basically followed the pattern of dispersed distribution in the A complement, conspicuous in telomeric/interstitial regions and preferential accumulation in the B chromosome. The B chromosome showed heterogeneous location of microsatellite probes CA, CAC and GA. The H3 and H4 histone genes were isolated from the total genome of the species and then the chromosomal mapping was performed by fluorescence in situ hybridization (FISH). The FISH signals showed high similarity for the probes H3 and H4 mapping in genomes of the populations analyzed. The sequences (GATA)n revealed a sex-specific trend between the chromosomal location in males and females at (LFS) and (LP) populations. Although species that comprise the Astyanax scabripinnis complex do not have morphologically differentiated sex chromosomes, the preferential GATA location – sex-associated – may represent a sex chromosome in differentiation. PMID:28919955

  4. New Astyanax from the upper rio Tapajós drainage, Central Brazil (Characiformes: Characidae

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    Vinicius A. Bertaco

    Full Text Available Astyanax utiariti, new species, is described from the upper rio Tapajós drainage, Mato Grosso, Brazil. Astyanax utiariti has a horizontally oval black humeral spot, a lozenge-shaped caudal-peduncle spot, continuing to the tip of the middle caudal-fin rays, and two brown bars in the humeral region that allows its inclusion in the A. bimaculatus species group. It also possesses a black stripe extending along midlateral body. The new species is distinguished from its congeners by a reticulate scale pattern, a black longitudinal stripe, toothless maxilla, larger dentary teeth and teeth of the inner row of the premaxilla with five to seven cusps, body depth 33.3-39.9% of standard length (SL, head length (HL 23.9-26.4% of SL, caudal-peduncle depth 12.0-13.4% of SL, orbital diameter 28.5-34.3% of HL, interorbital width 32.7-38.4% of HL, 36-38 perforated scales along the lateral line, and 22-26 branched anal-fin rays.

  5. Complex Evolutionary and Genetic Patterns Characterize the Loss of Scleral Ossification in the Blind Cavefish Astyanax mexicanus.

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    Kelly E O'Quin

    Full Text Available The sclera is the tough outer covering of the eye that provides structural support and helps maintain intraocular pressure. In some fishes, reptiles, and birds, the sclera is reinforced with an additional ring of hyaline cartilage or bone that forms from scleral ossicles. Currently, the evolutionary and genetic basis of scleral ossification is poorly understood, especially in teleost fishes. We assessed scleral ossification among several groups of the Mexican tetra (Astyanax mexicanus, which exhibit both an eyed and eyeless morph. Although eyed Astyanax surface fish have bony sclera similar to other teleosts, the ossicles of blind Astyanax cavefish generally do not form. We first sampled cavefish from multiple independent populations and used ancestral character state reconstructions to determine how many times scleral ossification has been lost. We then confirmed these results by assessing complementation of scleral ossification among the F1 hybrid progeny of two cavefish populations. Finally, we quantified the number of scleral ossicles present among the F2 hybrid progeny of a cross between surface fish and cavefish, and used this information to identify quantitative trait loci (QTL responsible for this trait. Our results indicate that the loss of scleral ossification is common-but not ubiquitous-among Astyanax cavefish, and that this trait has been convergently lost at least three times. The presence of wild-type, ossified sclera among the F1 hybrid progeny of a cross between different cavefish populations confirms the convergent evolution of this trait. However, a strongly skewed distribution of scleral ossicles found among surface fish x cavefish F2 hybrids suggests that scleral ossification is a threshold trait with a complex genetic basis. Quantitative genetic mapping identified a single QTL for scleral ossification on Astyanax linkage group 1. We estimate that the threshold for this trait is likely determined by at least three genetic

  6. Habitat use by Astyanax taeniatus (Jenyns, 1842 (Characiformes: Characidae in a coastal stream from Southeast Brazil

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    Luisa Resende Manna

    Full Text Available The habitat use of a stream-dwelling Astyanax taeniatus from the State of Rio de Janeiro was investigated. We performed 12 h of underwater observation in a 200 m long stretch in the upper Roncador stream and quantified the following microhabitat descriptors: (i water velocity, (ii distance from the stream bank, (iii substratum, and (iv water column depth. Microhabitat selectivity was analyzed by comparing the microhabitat used by fish and the microhabitat available in the study site as well as by applying the Ivlev Electivity Index to the microhabitat use data. Differences in the use and availability of the various microhabitats revealed non-stochastic patterns of spatial occupation by A. taeniatus, which was selective for two of the four analyzed microhabitats. Our findings indicated that A. taeniatusis associated with habitats that have higher depths, low water velocity, and sand and bedrock substratum.

  7. Toxicity and genotoxicity in Astyanax bimaculatus (Characidae induced by microcystins from a bloom of Microcystis spp

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    Ricardo Rocha Pavan da Silva

    2010-01-01

    Full Text Available Studies of genotoxicity in fish caused by cyanobacterial microcystins can be useful both in determining the sensitivity of native species, as well as comparing exposure routes. The genotoxicity caused by the microcystins LR and LA from a bloom collected in a eutrophic lake, was revealed in the fish Astyanax bimaculatus, a native species from South America. LC50 (72 h was determined as 242.81 µg L-1 and LD50 (72 h as 49.19 µg kg-1 bw. There was a significant increase of DNA damage in peripheral erythrocytes, following intraperitoneal injection (ip with tested concentrations of 24.58 µg kg-1 bw and 36.88 µg kg-1 bw, as well as through body exposure to a concentration of 103.72 µg L-1. Micronucleus (MN induction was observed after ip injections of 24.58 µg kg-1 bw and 36.88 µg kg-1 bw for 72 h, as well as following body exposure for 72 at 103.72 µg L-1. Thus, both exposure routes resulted in MN induction and DNA damage. Apoptosis-necrosis testing was carried out only by ip injection with concentrations of 24.58 µg -1 bw and 36.88 µg kg-1 bw. Exposure to microcystins at lower concentrations induced more apoptosis than necrosis in peripheral erythrocytes, whereas exposure at higher concentrations gave rise to both conditions. Thus, Astyanax bimaculatus can be considered as a species sensitive to the genotoxic effects caused by microcystins.

  8. Occurrence of intersexuality in " Lambaris" , Astyanax scabripinnis (Jenyns, 1842, small characids from the Brazilian streams

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    Maria de Fátima Pereira de Sá

    2008-04-01

    Full Text Available During studies carried out with a small characid (Astyanax scabripinnis, from the Brazilian streams located in Cerrado biome, some gonads of fishes exhibited sparse oocytes in perinucleolar stage embedded in normally developing testicular tissues. Another pattern of gonad intersex with vitellogenic oocytes and mature lobules was observed in the gonads of fishes collected from a reservoir supplied by the Atlantic Forest stream. These gonads in different stages of maturation were examined histologically. The results revealed the patterns occurring in fishes of the same species, from four different populations.Durante estudos efetuados com pequenos caracídeos (Astyanax scabripinnis de riachos do Cerrado brasileiro, localizados nos Estados de Minas Gerais e de São Paulo, foram encontrados alguns peixes com gônadas exibindo oócitos em estágio perinucleolar dispersos, embebidos em tecidos testiculares em desenvolvimento. Em exemplares da mesma espécie, provenientes de um riacho situado na Mata Atlântica do Estado de São Paulo, outro padrão de gônadas intersexuadas foi registrado, mostrando oócitos vitelogênicos e lóbulos maduros presentes na mesma gônada. As gônadas em diferentes estágios de maturação foram submetidas a análises histológicas. Os resultados obtidos mostram os padrões morfológicos e as freqüências de ocorrência dos intersexos encontrados em peixes do " complexo" A. scabripinnis provenientes de quatro diferentes populações. São discutidas as prováveis causas ambientais responsáveis por estas alterações.

  9. Differences in chemosensory response between eyed and eyeless Astyanax mexicanus of the Rio Subterráneo cave

    OpenAIRE

    2013-01-01

    Background In blind cave-dwelling populations of Astyanax mexicanus, several morphological and behavioral shifts occurred during evolution in caves characterized by total and permanent darkness. Previous studies have shown that sensory systems such as the lateral line (mechanosensory) and taste buds (chemosensory) are modified in cavefish. It has long been hypothesized that another chemosensory modality, the olfactory system, might have evolved as well to provide an additional mechanism for f...

  10. Lens apoptosis in the Astyanax blind cavefish is not triggered by its small size or defects in morphogenesis.

    Science.gov (United States)

    Hinaux, Hélène; Recher, Gaëlle; Alié, Alexandre; Legendre, Laurent; Blin, Maryline; Rétaux, Sylvie

    2017-01-01

    Blindness is a convergent trait in many cave animals of various phyla. Astyanax mexicanus cavefish is one of the best studied cave animals; however the mechanisms underlying eye degeneration in this species are not yet completely understood. The lens seems to play a central role, but only relatively late differentiation defects have been implicated in the cavefish lens apoptosis phenotype so far. Here, we used genetic crosses between Astyanax cavefish and surface fish to confirm that during development, lens size is independent of retina size. We then investigated whether the small size of the cavefish lens could directly cause cell death. Laser ablation experiments of lens placode cells in surface fish embryos showed that a small lens size is not sufficient to trigger lens apoptosis. We further examined potential lens morphogenesis defects through classical histology and live-imaging microscopy. From lens placode to lens ball, we found that lens invagination and formation of the lens epithelium and fiber cells occur normally in cavefish. We conclude that the main and deleterious defect in the Astyanax cavefish lens must concern the molecular control of lens cell function.

  11. Review of species of the Astyanax bimaculatus "caudal peduncle spot" subgroup sensu Garutti & Langeani (Characiformes, Characidae) from the rio La Plata and rio São Francisco drainages and coastal systems of southern Brazil and Uruguay.

    Science.gov (United States)

    Lucena, Carlos Alberto S De; Soares, Helena Gouvea

    2016-01-28

    The species of the Astyanax bimaculatus 'caudal peduncle spot' subgroup of the drainages of the rios La Plata and São Francisco, as well as southeastern coastal systems of Brazil and Uruguay, are revised. Two nominal species are considered valid and are redescribed: Astyanax lacustris and A. abramis. Astyanax jacuhiensis, A. asuncionensis and A. altiparanae are recognized as new junior synonyms of A. lacustris. Bertoniolus paraguayensisis recognized as a new junior synonym of A. abramis. The names Astyanax orbignyanus, A. vittatus, and A. borealis are considered species inquirendae. Notes on A. maculisquamis, included in the 'caudal peduncle spot' subgroup from rio Guaporé (rio Madeira drainage), and Astyanax bahiensis from Bahia, mistakenly considered of the same subgroup, are presented.

  12. Redescription of Astyanax guianensis Eigenmann 1909 (Characiformes: Characidae), a poorly known and widespread fish from the Amazon, Orinoco and Guiana Shield drainages.

    Science.gov (United States)

    Marinho, Manoela M F; Camelier, Priscila; Birindelli, José L O

    2015-03-16

    Astyanax guianensis is redescribed based on the holotype, paratypes, and additional specimens from the rio Essequibo in Guyana, rio Orinoco in Venezuela and from several localities in the Amazon river basin in Brazil, Colombia and Bolivia. Astyanax guianensis is diagnosed by having five to 10 maxillary teeth, 31 to 35 pored lateral-line scales, 21 to 25 branched anal-fin rays, and a dark vertical humeral blotch followed by a clear area and then by a dark longitudinal stripe, ending before the caudal-fin rays. In addition, comments on the importance of revisionary studies on the species of the Characidae are provided.

  13. Alguns trematódeos monogenéticos da família Capsalidae Baird, 1853, em peixes do Oceano Atlântico - Costa Continental Portuguesa e Costa do Norte da África Some monogenetic trematodes of Portuguese Continental Cost and North African Cost

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    Ursula Buhrnheim

    1973-01-01

    Full Text Available No presente trabalho é feito um estudo de cinco trematódeos monogenéticos pertencentes à família Capsalidae Baird, 1853. Para a subfamília Benedeniinae Johnston, 1931, foram criadas duas espécies pertencenteso ao gênero Benedenia Diesing, 1858: Benedenia pompatica sp. n., que muito se assemelha a Benedenia sciaenae (Beneden, 1852, diferindo desta principalmente pela estrutura do 2º e 3º pares de macroganchos e Benedenia innobilitata sp. n. que mais se aproxima de Benedenia jaliscana Bravo-Hollis, 1951, afastando-se desta espécie pela ausência do cirro armado e também pela estrutura e localização da vagina. Da subfamília Trochopodiane (Price, 1936 são apresentados novos hospedadores: Lepidotrigla cavillone para Trochopus pini (Beneden & Hesse, 1863 e Serranus cabrilla para Megalocotyle grandiloba Paperna e Kohn, 1964, sendo apresentadas com novas descrições e ilustrações. Ainda desta subfamília é criada uma nova espécie do gênero Allomegalocotyle (Robinson, 1961 Yamaguti, 1963. A. gabbari sp. n. diferencia-se de A. johnstoni (Robinson, 1961, única espécie do gênero, pela morfologia dos macroganchos, localização do poro vaginal e vesícula seminal bem desenvolvida e externa.In this paper we make a study of five monogenetic trematodes of the family Capsalidae Baird, 1853. We describe two new species of the genus Benedenia Diesing, 1858, Benedeniinae Johnston, 1931: Benedenia pompatica sp. n., which is very similar to Benedenia sciaenae (Beneden, 1852 abd differs from it mainly by the structure of the second and third pair of the haptoral hooks; and Benedenia innobilitata sp. n. near to Benedenia jaliscana Bravo-Hollis, 1951 does not have the armed cirrus, proper to the last and the structure and position of the vagina is also a considered characteristic. For the subfamily Trochopodinae (Price, 1936 we give new hosts: Lepidotrigla cavillone for Trochopus pini (Beneden & Hesse, 1863 and Serranus cabrilla for Megalocotyle

  14. Histological alterations in liver and testis of Astyanax aff. bimaculatus caused by acute exposition to zinc

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    Daiane Cristina Marques dos Santos*

    2015-04-01

    Full Text Available This study investigated the effect of acute exposition to zinc (Zn on histology of the liver and testes of yellow tail lambari (Astyanax aff. bimaculatus. The exposure consisted of six concentrations of Zn (0, 3, 5, 10, 15, and 20 mg/L for 96 hours of exposure. Fragments of liver and testis were routinely processed and embedded in plastic resin based on glycol methacrylate. Fragments of bones, muscles, liver and testis were dehydrated and digested to quantify the absorption levels of Zn in the tissue. Acute exposure to concentrations above 10mg/L has produced structural changes in the liver and gonads. The changes found in the liver were vascular congestion; decrease of cellular volume; displacement of the hepatocyte nucleus; necrosis; disarrangement of cordon structure; leukocyte infiltrate and vacuolization. The changes found in the gonads were ruptured cyst, delayed development of germ cells, pyknotic nucleus, cell cluster, displacement of cyst wall and vacuolization. The histological changes observed were compatible with the increasing concentration of zinc in environment, compromising liver and reproductive functions, because there was an increase in relative frequency of hepatocytes and reduced sperm production

  15. Intestinal and liver morphometry of the Yellow Tail Tetra (Astyanax altiparanae fed with oregano oil

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    POLLYANNA M.F. FERREIRA

    2016-06-01

    Full Text Available ABSTRACT This study aimed to evaluate the effect of oregano oil on the intestinal and liver morphometry of yellow tail tetra, Astyanax altiparanae. Fish (1.46 ± 0.09 g were kept in a 60-L aquaria, at a stocking density of 0.5 fi sh L-1. Six diets containing varying amounts of oregano oil were evaluated (0.0; 0.5; 1.0; 1.5; 2.0 and 2.5 g of oregano oil kg-1. At the end of 90 days, the fi sh were euthanised. Four intestines and four livers were collected per treatment, which were fi xed in Bouin and embedded in resin. For height and width folds, the absorption surface area and thickness of the muscular layer a positive linear effect of oregano oil was observed. A decrescent linear effect on the total number of goblet cells was also observed. For the cytoplasmic percentage of hepatocytes and liver glycogen, a positive linear effect of oregano oil was observed. There was a decreasing linear effect on the percentage of nuclei in the hepatocytes and capillaries. Thus, the oregano essential oil promotes increased absorption areas, modulates the amount of goblet cells involved in protecting the intestinal mucosa and promotes cytoplasmic increase with greater deposition of liver glycogen in yellow tail tetra.

  16. Transport of Astyanax altiparanae Garutti and Britski, 2000 in saline water

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    Ana Lúcia Salaro

    2015-08-01

    Full Text Available Two experiments were performed. The first aimed to assess the tolerance of fingerlings Astyanax altiparanae to water salinity. Fish were exposed to salinity of 0, 3, 6, 9, 12 or 15 g NaCl L-1 for 96 hours. The fish mortality was 0%, in the levels of 0, 3 and 6 g L-1; 75% in the level of 9 g L-1and 100% at 12 and 15 g L-1 of common salt. The second experiment aimed to assess the parameters of water quality, mortality and blood glucose during transport. For this, A. altiparanae were stored in plastic bags at 22, 30 and 37 g of fish L-1 stocking densities and salinity of 0, 3, 6 and 9 g L-1, for. Fish showed similar mortality levels in the different salinities and stocking densities. The increase in fish density reduced the dissolved oxygen levels and salinity decreased the pH. The blood glucose levels were higher in those fish with 0 g L-1 salinity and higher stocking densities. The addition of salt to the water reduces the stress responses of A. altiparanae during transport.

  17. Genome Editing in Astyanax mexicanus Using Transcription Activator-like Effector Nucleases (TALENs).

    Science.gov (United States)

    Kowalko, Johanna E; Ma, Li; Jeffery, William R

    2016-06-20

    Identifying alleles of genes underlying evolutionary change is essential to understanding how and why evolution occurs. Towards this end, much recent work has focused on identifying candidate genes for the evolution of traits in a variety of species. However, until recently it has been challenging to functionally validate interesting candidate genes. Recently developed tools for genetic engineering make it possible to manipulate specific genes in a wide range of organisms. Application of this technology in evolutionarily relevant organisms will allow for unprecedented insight into the role of candidate genes in evolution. Astyanax mexicanus (A. mexicanus) is a species of fish with both surface-dwelling and cave-dwelling forms. Multiple independent lines of cave-dwelling forms have evolved from ancestral surface fish, which are interfertile with one another and with surface fish, allowing elucidation of the genetic basis of cave traits. A. mexicanus has been used for a number of evolutionary studies, including linkage analysis to identify candidate genes responsible for a number of traits. Thus, A. mexicanus is an ideal system for the application of genome editing to test the role of candidate genes. Here we report a method for using transcription activator-like effector nucleases (TALENs) to mutate genes in surface A. mexicanus. Genome editing using TALENs in A. mexicanus has been utilized to generate mutations in pigmentation genes. This technique can also be utilized to evaluate the role of candidate genes for a number of other traits that have evolved in cave forms of A. mexicanus.

  18. Replacement of animal protein with vegetable protein in the diets of Astyanax altiparanae

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    Fábio Rosa Sussel

    2014-09-01

    Full Text Available The aim of this study was to evaluate the effect of replacing animal protein with vegetable protein sources on the productive performance of Astyanax altiparanae (lambari-do-rabo-amarelo. Five experimental diets were formulated with increasing replacement levels of animal protein by vegetable protein. A total of 9000 individuals (initial mean weight 1.18 ± 0.12 g, initial mean length 2.1 ± 0.3 cm were distributed in 20 net cages (1 m3 with a density of 450 ind. m-3. Cages were randomly placed in a pond (180 m2, 1.5 m deep, 10% water renewal per day. After 63 days of cultivation, total count and individual biometrics from 20% of each experimental unit were taken. Mean weight, total length, survival, feed conversion, biomass weight gain and proximate body composition were evaluated. The experimental design was completely randomized with five treatments and four replications. The reduction in the formulation cost achieved by increasing levels of vegetable protein compensated the slight decrease in biomass gain. Besides that, inclusion of vegetable protein resulted in greater fat deposition, suggesting future exploration of A. altiparanae as a functional food.

  19. Pathological assessment of farmed yellowtail tetra Astyanax altiparanae infested by Acusicola sp. (Ergasilidae

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    Santiago Benites de Pádua

    2015-11-01

    Full Text Available This study registers for the first time the copepod Acusicola sp. infesting the gills of farmed yellowtail tetra Astyanax altiparanae, as well as new information on gross pathology and gill alterations. Five specimens of yellowtail tetra showing slow swimming, respiratory difficulty, scaleness and darkened skin were examined. Fish were analysed in situ for ectoparasites diagnosis. Fragments of the gill arches were removed and processed according to usual histopathology. The gills showed focal and multifocal paleness and whitish areas besides the congestion and hemorrhage signs on the gill filaments. Several white spots attached to the gill filament apex with slight movement were identified as the ergasilid crustacean. Histopathological analysis revealed the gill and blood vessels compression. It was also observed proliferative alterations close to gill filament apex, hyperplasia, total fusion and subepithelial oedema of the secondary lamellae, proliferation of the mucus cells, and inflammatory infiltrate by eosinophilic granular cells surrounding the parasite attachment region. The best management practices and the implementation of diagnostic program are also discussed.

  20. Evidence for multiple genetic forms with similar eyeless phenotypes in the blind cavefish, Astyanax mexicanus.

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    Dowling, Thomas E; Martasian, David P; Jeffery, William R

    2002-04-01

    A diverse group of animals has adapted to caves and lost their eyes and pigmentation, but little is known about how these animals and their striking phenotypes have evolved. The teleost Astyanax mexicanus consists of an eyed epigean form (surface fish) and at least 29 different populations of eyeless hypogean forms (cavefish). Current alternative hypotheses suggest that adaptation to cave environments may have occurred either once or multiple times during the evolutionary history of this species. If the latter is true, the unique phenotypes of different cave-dwelling populations may result from convergence of form, and different genetic changes and developmental processes may have similar morphological consequences. Here we report an analysis of variation in the mitochondrial NADH dehydrogenase 2 (ND2) gene among different surface fish and cavefish populations. The results identify a minimum of two genetically distinctive cavefish lineages with similar eyeless phenotypes. The distinction between these divergent forms is supported by differences in the number of rib-bearing thoracic vertebrae in their axial skeletons. The geographic distribution of ND2 haplotypes is consistent with roles for multiple founder events and introgressive hybridization in the evolution of cave-related phenotypes. The existence of multiple genetic lineages makes A. mexicanus an excellent model to study convergence and the genes and developmental pathways involved in the evolution of the eye and pigment degeneration.

  1. Differentially expressed genes identified by cross-species microarray in the blind cavefish Astyanax.

    Science.gov (United States)

    Strickler, Allen G; Jeffery, William R

    2009-03-01

    Changes in gene expression were examined by microarray analysis during development of the eyed surface dwelling (surface fish) and blind cave-dwelling (cavefish) forms of the teleost Astyanax mexicanus De Filippi, 1853. The cross-species microarray used surface and cavefish RNA hybridized to a DNA chip prepared from a closely related species, the zebrafish Danio rerio Hamilton, 1822. We identified a total of 67 differentially expressed probe sets at three days post-fertilization: six upregulated and 61 downregulated in cavefish relative to surface fish. Many of these genes function either in eye development and/or maintenance, or in programmed cell death. The upregulated probe set showing the highest mean fold change was similar to the human ubiquitin specific protease 53 gene. The downregulated probe sets showing some of the highest fold changes corresponded to genes with roles in eye development, including those encoding gamma crystallins, the guanine nucleotide binding proteins Gnat1 and Gant2, a BarH-like homeodomain transcription factor, and rhodopsin. Downregulation of gamma-crystallin and rhodopsin was confirmed by in situ hybridization and immunostaining with specific antibodies. Additional downregulated genes encode molecules that inhibit or activate programmed cell death. The results suggest that cross-species microarray can be used for identifying differentially expressed genes in cavefish, that many of these genes might be involved in eye degeneration via apoptotic processes, and that more genes are downregulated than upregulated in cavefish, consistent with the predominance of morphological losses over gains during regressive evolution.

  2. A developmental staging table for Astyanax mexicanus surface fish and Pachón cavefish.

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    Hinaux, Hélène; Pottin, Karen; Chalhoub, Houssein; Père, Stéphane; Elipot, Yannick; Legendre, Laurent; Rétaux, Sylvie

    2011-12-01

    Every model species requires its own developmental table. Astyanax mexicanus, a teleost fish comprising both sighted river and blind cave populations, is becoming more and more important in the field of developmental and evolutionary biology. As such, a developmental staging table is increasingly necessary, particularly since comparative analysis of early developmental events is widely employed by researchers. We collected freshly spawned embryos from surface fish and Pachón cavefish populations. Embryos were imaged every 10-12 min during the first day of development, and less frequently in the following days. The results provide an illustrated comparison of selected developmental stages from one cell to hatching of these two populations. The two morphs show an essentially synchronous development regarding major events such as epiboly, neurulation, somitogenesis, heart beating, or hatching. We also present data on particular morphological characters appearing during larval development, such as eye size, yolk regression, swim bladder, and fin development. Some details about the development of F1 Pachón cave×surface hybrids are also given. Comparisons are made with Danio rerio (zebrafish) development.

  3. The lens controls cell survival in the retina: Evidence from the blind cavefish Astyanax.

    Science.gov (United States)

    Strickler, Allen G; Yamamoto, Yoshiyuki; Jeffery, William R

    2007-11-15

    The lens influences retinal growth and differentiation during vertebrate eye development but the mechanisms are not understood. The role of the lens in retinal growth and development was studied in the teleost Astyanax mexicanus, which has eyed surface-dwelling (surface fish) and blind cave-dwelling (cavefish) forms. A lens and laminated retina initially develop in cavefish embryos, but the lens dies by apoptosis. The cavefish retina is subsequently disorganized, apoptotic cells appear, the photoreceptor layer degenerates, and retinal growth is arrested. We show here by PCNA, BrdU, and TUNEL labeling that cell proliferation continues in the adult cavefish retina but the newly born cells are removed by apoptosis. Surface fish to cavefish lens transplantation, which restores retinal growth and rod cell differentiation, abolished apoptosis in the retina but not in the RPE. Surface fish lens deletion did not cause apoptosis in the surface fish retina or affect RPE differentiation. Neither lens transplantation in cavefish nor lens deletion in surface fish affected retinal cell proliferation. We conclude that the lens acts in concert with another optic component, possibly the RPE, to promote retinal cell survival. Accordingly, deficiency in both optic structures may lead to eye degeneration in cavefish.

  4. Molecular study of Astyanax altiparanae (Osteichthyes, Characidae) as a probable species complex.

    Science.gov (United States)

    Deprá, I C; Gomes, V N; Deprá, G C; Oliveira, I J; Prioli, S M A P; Prioli, A J

    2014-08-07

    Astyanax altiparanae, belonging to the bimaculatus group, which includes species with similar colors and morphology, occurs in the upper Paraná River basin. As the use of mitochondrial DNA has made great strides in the diagnosis of species, in previous researches, two strains were detected in A. altiparanae with a high divergence in the D-loop region, provisionally called AltoPR and AltoPR-D. Evidence led to the hypothesis that the two strains did not belong to the same species. Phylogenetic hypotheses were produced by maximum-likelihood. Mean internal distances of the AltoPR and AltoPR-D groups were respectively 0.002 and 0.003, with the distance between them being 0.037. Sequences from GenBank of specimens collected from the Paraíba do Sul River basin were also divided into two groups, of which one may be identified as AltoPR. Since the other group provided an intermediate distance when compared to AltoPR-D, an in-depth investigation was required. The other species analyzed showed a greater distance and was revealed to be a monophyletic taxon. The results suggested that they are really two species and that neither corresponds to the other species used in the current study.

  5. Identification and chromosome mapping of repetitive elements in the Astyanax scabripinnis (Teleostei: Characidae) species complex.

    Science.gov (United States)

    Barbosa, Patrícia; de Oliveira, Luiz Antonio; Pucci, Marcela Baer; Santos, Mateus Henrique; Moreira-Filho, Orlando; Vicari, Marcelo Ricardo; Nogaroto, Viviane; de Almeida, Mara Cristina; Artoni, Roberto Ferreira

    2015-02-01

    Most part of the eukaryotic genome is composed of repeated sequences or multiple copies of DNA, which were considered as "junk DNA", and may be associated to the heterochromatin. In this study, three populations of Astyanax aff. scabripinnis from Brazilian rivers of Guaratinguetá and Pindamonhangaba (São Paulo) and a population from Maringá (Paraná) were analyzed concerning the localization of the nucleolar organizer regions (Ag-NORs), the As51 satellite DNA, the 18S ribosomal DNA (rDNA), and the 5S rDNA. Repeated sequences were also isolated and identified by the Cot - 1 method, which indicated similarity (90%) with the LINE UnaL2 retrotransposon. The fluorescence in situ hybridization (FISH) showed the retrotransposon dispersed and more concentrated markers in centromeric and telomeric chromosomal regions. These sequences were co-localized and interspaced with 18S and 5S rDNA and As51, confirmed by fiber-FISH essay. The B chromosome found in these populations pointed to a conspicuous hybridization with LINE probe, which is also co-located in As51 sequences. The NORs were active at unique sites of a homologous pair in the three populations. There were no evidences that transposable elements and repetitive DNA had influence in the transcriptional regulation of ribosomal genes in our analyses.

  6. The effects of temperature and busulfan (Myleran) on the yellowtail tetra Astyanax altiparanae (Pisces, Characiformes) spermatogenesis.

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    de Siqueira-Silva, Diógenes Henrique; Silva, Amanda Pereira dos Santos; Ninhaus-Silveira, Alexandre; Veríssimo-Silveira, Rosicleire

    2015-10-01

    We aimed to standardize a protocol to suppress spermatogenesis in the characiform fish, Astyanax altiparanae, for future use as a host in germ cell transplant research, opening opportunities for a range of studies, such as spermatogenesis analyses and transgenesis because this species presents livestock characteristics to be used as a biological model. The effects of the chemotherapeutic busulfan (formulated as Myleran), which is used as medicine, therefore not as toxic to humans manipulation as analytical grade busulfan (Fluka) used in previous studies, were evaluated at physiological temperature of 28 °C, ideal for growth and reproduction of A altiparanae, and also at increased temperature 35 °C. The temperature groups were divided into three treatment groups: busulfan, DMSO only, and an untreated control. Macroscopic, histologic, stereological, and ultrastructure analysis showed that, at 28 °C, busulfan did not cause depletion of germ cells in A altiparanae. However, at 35 °C, sterilization was observed 3 weeks after the initial application. Similar results were obtained with maintenance of fish at 35 °C for a longer period with no accompanying Myleran treatment. This procedure allows reduction in stress and lower mortality resulting from manipulation during busulfan injection and is also suitable for mass treatment because large numbers of fish can be incubated in warm water.

  7. Ultramorphological changes in gill rakers of Astyanax altiparanae (Characidae) kept in contaminated environments.

    Science.gov (United States)

    Lopes, F P; Pereira, B F; Alves, R M S; Valim, J R T; Figueiredo, F A T; Pitol, D L; Caetano, F H

    2017-08-01

    Most water bodies in Brazil, and in the world, are contaminated by some types of pollutants, ranging from sewage to metal/chemicals, carcinogenic products, and biodegradable detergents. Despite the extensive knowledge on their effects on fish biology and especially on gill morphology, research that concerns their impacts on gill rakers and implications in parameters such as food consumption cannot be found in the literature. Gill rakers are vital because, together with gills, they are responsible for the defense and protection of the organism and for selecting appropriate food for survival. When detergents, which can act as toxic chemical agents, get in contact with the body of the fish, they can cause severe effects that must be understood. Therefore, our study investigated ultramorphological changes in gill rakers of Astyanax altiparanae (Lambeth) caused by the exposure to biodegradable detergents. Fish were exposed to a 1 mg/L dilution of a mixture of detergents and pure water from an artesian well for 5 months. Results revealed that the first month of exposure to detergent caused dilation of chemical receptors in taste buds and the rise of a large number of orifices for mucus release among pavement cells in gill rakers, although only a small amount of mucus was found in fish exposed both to pure water and the detergent dilution. After 5 months, there was an increase in the dilation of these chemoreceptors, excess mucus on gill rakers of detergent groups, and the emergence of microbridges between microridges in pavement cells.

  8. Comparative genetics of the central nervous system in epigean and hypogean Astyanax mexicanus.

    Science.gov (United States)

    Strickler, Allen G; Soares, Daphne

    2011-03-01

    The extreme environment of subterranean caves presents an adaptive challenge to troglobitic organisms. The mechanisms by which natural selection modify an ancestral surface neural circuit to produce a novel subterranean behavior remain a mystery. To address this question, we performed cross species microarray experiments to compare differences in gene expression levels in the adult brain of the teleost Astyanax mexicanus. This species provides a unique opportunity for comparative genetic studies as it consists of extant epigean (surface) and hypogean (cave) conspecifics. Microarray experiments herein revealed significant changes in transcription levels of seventeen genes, several of which are important for behaviors involved in metabolic management. We focused on genes central to three neurotransmission and neuromodulation networks: the endocannabinoid system (Cannabinoid receptor CB1), the dopaminergic system (Tyrosine 3-monooxygenase/tryptophan 5-monooxygenase activation protein) and the glutamatergic system (glutamate receptor AMPA 2a). All three genes were upregulated in the hypogean form of A. mexicanus compared to the epigean form, indicating that behavioral differences in the hypogean form of the species could be due to alterations in expression levels of several key genes. This information provides insights into the complex relationships among environmental factors, genetics, nervous systems and adaptive behavior, and can subsequently help us understand how these interactions affect behavior in other biological systems.

  9. Astyanax douradilho, a new characid fish from the rio Tramandaí system, southern Brazil (Characiformes: Characidae).

    Science.gov (United States)

    Bertaco, Vinicius A

    2014-05-07

    Astyanax douradilho, new species, is described from the rio Tramandaí system, coastal drainage of Rio Grande do Sul State, Brazil. The new species is distinguished from its congeners by possessing 37-39 perforated scales along the lateral line, 3-5 maxillary tricuspid teeth, 22-24 branched anal-fin rays, absence of a conspicuous dark stripe from humeral region to caudal peduncle, two vertically elongated humeral spots, head length (26.0-29.9% of standard length), upper jaw length (43.8-50.6% of head length), and snout length (23.0-28.6% of HL).

  10. The genus Bipolaris

    NARCIS (Netherlands)

    Manamgoda, D.S.; Rossman, A.Y.; Castlebury, L.A.; Crous, P.W.; Madrid, H.; Chukeatirote, E.; Hyde, K.D.

    2014-01-01

    The genus Bipolaris includes important plant pathogens with worldwide distribution. Species recognition in the genus has been uncertain due to the lack of molecular data from ex-type cultures as well as overlapping morphological characteristics. In this study, we revise the genus Bipolaris based on

  11. Molecular cloning and expression analysis of dmrt1 and sox9 during gonad development and male reproductive cycle in the lambari fish, astyanax altiparanae

    NARCIS (Netherlands)

    Adolfi, Mateus C.; Carreira, Ana C O; Jesus, Lázaro W O; Bogerd, Jan; Funes, Rejane M.; Schartl, Manfred; Sogayar, Mari C.; Borella, Maria I.

    2015-01-01

    Background: The dmrt1 and sox9 genes have a well conserved function related to testis formation in vertebrates, and the group of fish presents a great diversity of species and reproductive mechanisms. The lambari fish (Astyanax altiparanae) is an important Neotropical species, where studies on molec

  12. Molecular cloning and expression analysis of dmrt1 and sox9 during gonad development and male reproductive cycle in the lambari fish, astyanax altiparanae

    NARCIS (Netherlands)

    Adolfi, Mateus C.; Carreira, Ana C O; Jesus, Lázaro W O; Bogerd, Jan|info:eu-repo/dai/nl/098250531; Funes, Rejane M.; Schartl, Manfred; Sogayar, Mari C.; Borella, Maria I.

    2015-01-01

    Background: The dmrt1 and sox9 genes have a well conserved function related to testis formation in vertebrates, and the group of fish presents a great diversity of species and reproductive mechanisms. The lambari fish (Astyanax altiparanae) is an important Neotropical species, where studies on

  13. Cytotaxonomy, heterochromatic polymorphism and natural triploidy of a species of Astyanax (Pisces, Characidae endemic to the Iguaçu river basin

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    Daniel Luis Zanella Kantek

    2007-01-01

    Full Text Available Cytogenetic analysis with Astyanax sp. D revealed a karyotype of 2n=50 with 2M+26SM+6ST+16A, besides a triploid specimen showing 2n=75 chromosomes (3M+39SM+9ST+24A. C-banding strongly stained the terminal regions of several SM-ST-A chromossomes. Two pairs of acrocentric chromosomes presented interstitial heterochromatin, this state being polymorphic and occuring due to possible paracentric inversions. The results obtained with the AluI restriction enzyme and A3 chromomycin were similar to the C-banding. Relationships were proposed between Astyanax sp. D and A. scabripinnis, as well as considerations for a possible origin of the triploid specimen (2n=3x=75. When comparing the present results with cytogenetic features of other endemic Astyanax species in the Iguaçu river (A. sp. B and C, a clear differentiation was observed between them, indicating cytogenetics as an important cytotaxonomic tool.Análises citogenéticas em Astyanax sp. D evidenciaram 2n=50 cromossomos e um cariótipo com 2M+26SM+6ST+16A. O bandamento C destacou as regiões teloméricas de diversos cromossomos SM-ST-A. Dois pares de cromossomos acrocêntricos possuem heterocromatina intersticial, sendo este estado polimórfico decorrente de prováveis inversões paracêntricas. O resultados obtidos com a enzima de restrição AluI e a Cromomicina A3 foram semelhantes aos do bandamento C. São propostas relações de parentesco entre Astyanax sp. D e Astyanax scabripinnis, bem como considerações sobre a possível origem do exemplar triplóide (2n=3x=75. Ao comparar os resultados deste trabalho com outras espécies de Astyanax do Rio Iguaçu, estas espécies se tornam claramente distinguíveis, evidenciando a citogenética como uma importante ferramenta taxonômica.

  14. Histological alterations in gills of Astyanax aff. bimaculatus caused by acute exposition to zinc.

    Science.gov (United States)

    dos Santos, Daiane Cristina Marques; da Matta, Sérgio Luis Pinto; de Oliveira, Juraci Alves; dos Santos, Jorge Abdala Dergam

    2012-11-01

    Increasing contamination of aquatic ecosystems by metals has caused various morphological, physiological and biochemical changes in aquatic organisms, and the gills of fish are recognized as indicators of environmental quality. In this context, the present work proposed to study the effects of different concentrations of zinc (Zn) in the histology of gills of yellow tail lambari (Astyanax aff. bimaculatus) after acute exposure. Seventy-two adult males of A. aff. bimaculatus were used, the treatments were six concentrations of Zn: 0; 3; 5; 10; 15; and 20 mg/L of water, by 96 h, and gills, muscle and bone fragments were removed. Fragments of gills were fixed and included, sectioned in a rotary microtome and stained with toluidin blue. Fragments of bone, muscle and gills were dehydrated and digested to quantify the absorption of Zn. The median lethal concentration (LC(50)) 96 h after Zn acute exposure was 10 mg/L of water. Noteworthy, Zn was highly toxic in acute exposure trials starting at the concentration 5 mg/L. The exposure of fish to the metal caused branchial histopathological changes correlated with increasing concentration, caused the death of fish at concentrations of 10, 15 and 20 mg/L. The histological alterations observed in the gills were hyperplasia, lamellar fusion, aneurysm, destruction of the lamellar epithelium, rupture of membrane, deletion of secondary lamellar high, which presented more severity in treatments exposed to the highest concentrations. In conclusion, gills of A. aff. bimaculatus presented profound histological alterations as a result of Zn exposure, and hence, proved to be excellent indicators of environmental contamination.

  15. Astyanax mexicanus, the Blind Mexican Cave Fish: A Model for Studies in Development and Morphology.

    Science.gov (United States)

    Borowsky, Richard

    2008-11-01

    INTRODUCTIONThe perpetual darkness of caves has two important consequences for permanent inhabitants. First, eyes and pigmentation lose their primary functions. Second, in the absence of photosynthesis, food is rare. For these reasons, cave-adapted species typically have reduced eyes and pigmentation and increased or more efficient metabolisms. Additionally, other senses are usually augmented to compensate for the loss of vision. Identifying the genetic bases underlying these phenotypic changes will enhance our understanding of the specific pathways involved in control of these phenotypes and, in general, the evolutionary process. Unfortunately, the genetics of most cave animals cannot be studied because they are not easily bred. Blind Mexican tetras, Astyanax mexicanus, are the valuable exception to this rule because fish from the various cave populations are fully interfertile with one another and with eyed sister forms still living in nearby surface streams. Hybrids between surface and cave forms permit genetic analysis of their differences, and study of the pure forms as well as of hybrids allows study of their developmental differences. Quantitative trait loci (QTL) analysis has already identified some specific genes responsible for differences between cave and surface forms as well as other likely candidates; more will be added in the future. This system is a valuable addition to the array of existing models for the study of developmental and evolutionary genetics because cave populations are repositories of numerous naturally occurring mutations affecting development of the eyes and other senses, pigmentation, bone structure, metamerism, and metabolism. These alleles have been prescreened by natural selection for high viability, which simplifies their study. In contrast, new alleles obtained through mutagenesis in other model species are typically burdened with lower viability.

  16. Evolution of pigment cell regression in the cavefish Astyanax: a late step in melanogenesis.

    Science.gov (United States)

    McCauley, David W; Hixon, Ernest; Jeffery, William R

    2004-01-01

    Pigmentation and eyes are often lost in cave-adapted animals. Although the mechanisms of eye degeneration are beginning to be understood, little is known about the evolutionary and developmental processes involved in pigment cell regression. In teleost embryos, a population of neural crest cells migrates into the body wall and differentiates into melanophores, xanthophores, and iridophores. All three pigment cell types are present in the eyed surface-dwelling form (surface fish) of the teleost Astyanax mexicanus. However, melanophores are absent or substantially reduced in number in various derived populations of the conspecific blind cave-dwelling form (cavefish). We show here that tyrosinase-positive melanoblasts are present in cavefish. DiI labeling revealed a population of trunk neural crest cells in cavefish embryos that migrate to locations normally occupied by differentiated melanophores. We also discovered a cell population in cavefish embryos and adults resembling melanoblasts in several features, including the ability to synthesize melanin when supplied with the tyrosinase substrate l-dopa. DiI-tyrosinase double-labeling and neural keel explant experiments showed that the tyrosinase-positive cells are derived from the neural crest. The number of melanoblasts varies in different adult cavefish populations relative to the extent of melanophore reduction. Although cavefish melanoblasts can synthesize melanin from exogenous l-dopa, they are unable to convert exogenous l-tyrosine to l-dopa and melanin. We conclude that pigment cell regression in cavefish is mediated by an evolutionary change late in melanogenesis that may involve an impediment in the ability to convert l-tyrosine to l-dopa and melanin.

  17. Toxicity and genotoxicity in Astyanax bimaculatus (Characidae) induced by microcystins from a bloom of Microcystis spp

    Science.gov (United States)

    2010-01-01

    Studies of genotoxicity in fish caused by cyanobacterial microcystins can be useful both in determining the sensitivity of native species, as well as comparing exposure routes. The genotoxicity caused by the microcystins LR and LA from a bloom collected in a eutrophic lake, was revealed in the fish Astyanaxbimaculatus, a native species from South America. LC50 (72 h) was determined as 242.81 μg L -1 and LD50 (72 h) as 49.19 μg kg -1 bw. There was a significant increase of DNA damage in peripheral erythrocytes, following intraperitoneal injection (ip) with tested concentrations of 24.58 μg kg -1 bw and 36.88 μg kg -1 bw, as well as through body exposure to a concentration of 103.72 μg L -1 . Micronucleus (MN) induction was observed after ip injections of 24.58 μg kg -1 bw and 36.88 μg kg -1 bw for 72 h, as well as following body exposure for 72 at 103.72 μg L -1 . Thus, both exposure routes resulted in MN induction and DNA damage. Apoptosis-necrosis testing was carried out only by ip injection with concentrations of 24.58 μg kg -1 bw and 36.88 μg kg- 1 bw. Exposure to microcystins at lower concentrations induced more apoptosis than necrosis in peripheral erythrocytes, whereas exposure at higher concentrations gave rise to both conditions. Thus, Astyanax bimaculatus can be considered as a species sensitive to the genotoxic effects caused by microcystins. PMID:21637586

  18. Gene flow and population structure in the Mexican blind cavefish complex (Astyanax mexicanus

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    Bradic Martina

    2012-01-01

    Full Text Available Abstract Background Cave animals converge evolutionarily on a suite of troglomorphic traits, the best known of which are eyelessness and depigmentation. We studied 11 cave and 10 surface populations of Astyanax mexicanus in order to better understand the evolutionary origins of the cave forms, the basic genetic structuring of both cave and surface populations, and the degree to which present day migration among them affects their genetic divergence. Results To assess the genetic structure within populations and the relationships among them we genotyped individuals at 26 microsatellite loci. We found that surface populations are similar to one another, despite their relatively large geographic separation, whereas the cave populations are better differentiated. The cave populations we studied span the full range of the cave forms in three separate geographic regions and have at least five separate evolutionary origins. Cave populations had lower genetic diversity than surface populations, correlated with their smaller effective population sizes, probably the result of food and space limitations. Some of the cave populations receive migrants from the surface and exchange migrants with one another, especially when geographically close. This admixture results in significant heterozygote deficiencies at numerous loci due to Wahlund effects. Cave populations receiving migrants from the surface contain small numbers of individuals that are intermediate in both phenotype and genotype, affirming at least limited gene flow from the surface. Conclusions Cave populations of this species are derived from two different surface stocks denoted "old" and "new." The old stock colonized caves at least three times independently while the new stock colonized caves at least twice independently. Thus, the similar cave phenotypes found in these caves are the result of repeated convergences. These phenotypic convergences have occurred in spite of gene flow from surface

  19. Effects of acidic water, aluminum, and manganese on testicular steroidogenesis in Astyanax altiparanae.

    Science.gov (United States)

    Kida, Bianca Mayumi Silva; Abdalla, Raisa Pereira; Moreira, Renata Guimarães

    2016-10-01

    Metals can influence the gonadal steroidogenesis and endocrine systems of fish, thereby affecting their reproduction. The effects of aluminum and manganese in acidic water were investigated on steroidogenesis in sexually mature male Astyanax altiparanae. Whether mature male fish recover from the effects of metals in metal-free water was also assessed. The fish were exposed to 0.5 mg L(-1) of isolated or combined aluminum and manganese in acidic pH (5.5) to keep the metals bioavailable. The fish underwent 96 h of acute exposure, and samples were taken 24 and 96 h after the beginning of the experiment. The fish were then maintained in metal-free water for 96 h. Plasma levels of testosterone, 11-ketotestosterone, 17β-estradiol, and cortisol were measured. Acidic water increased the plasma concentration of testosterone and 11-ketotestosterone. Aluminum increased the testosterone levels after 96 h of exposure. Manganese increased the 17β-estradiol levels after 24 h of exposure and maintained at high levels until the end of the experiment. With the exception of acidic pH, which increased cortisol levels after 24 h of exposure, no changes were observed in this corticosteroid during the acute experiment. Aluminum and manganese together also altered steroid levels but without a standard variation. The fish recovered from the effects of most exposure conditions after 96 h in metal-free water. A. altiparanae could use reproductive tactics to trigger changes in testicular steroidogenesis by accelerating spermatogenesis and spermiogenesis, which may interfere with their reproductive dynamics.

  20. Nematodes of Astyanax fasciatus (Actinopterygii: Characidae and their parasitic indices in the São Francisco river, Brazil

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    Flavia Guerra Vieira-Menezes

    Full Text Available Abstract The endoparasite fauna of Astyanax fasciatus from the upper São Francisco river was investigated and ecological parameters and morphological and morphometric data on the parasites are presented. A total of 74 specimens of banded astyanax were collected downstream from the Três Marias dam, municipality of Três Marias, Minas Gerais (18°12’32”S, 45°15’41”W in January 2011 and January 2012. Eleven taxa of Nematoda were found: Contracaecum sp.; Hysterothylacium sp.; Goezia sp.; Brevimulticaecum sp.; Procamallanus sp.; Procamallanus (Spirocamallanus saofranciscencis; Cystidicoloides sp.; Spinitectus rodolphiheringi; Rhabdochona sp.; Spiroxys sp.; and Eustrongylides sp.. The fauna of A. fasciatus consisted of by larval specimens of Contracaecum sp., Hysterothylacium sp., Brevimulticaecum sp., Cystidicoloides sp., and Spiroxys sp., and by adult specimens of P. saofranciscencis, whose prevalence was greater than 10%. Thus, this fish acts as an intermediate host of some species of larval nematodes especially, Anisakidae and Acanthocheilidae (Brevimulticaecum sp., new host record and new locality. It participates in transmitting species such Rhabdochona sp. to carnivorous fish and also acts as a definitive host for P. saofranciscencis and S. rodolphiheringi in the upper São Francisco river.

  1. O lambari Astyanax altiparanae (Characidae pode ser um dispersor de sementes? - DOI: 10.4025/actascibiolsci.v25i2.2045 Can lambari, Astyanax altiparanae (Characidae, be a seed disperser? - DOI: 10.4025/actascibiolsci.v25i2.2045

    Directory of Open Access Journals (Sweden)

    Leandro Muller Gomiero

    2003-04-01

    Full Text Available Este trabalho caracterizou a alimentação natural de Astyanax altiparanae na sub-bacia do rio Corumbataí e bacia do rio Jacaré-pepira, com enfoque principal na ingestão de sementes de Croton urucurana. Os itens alimentares de Astyanax altiparanae, em ordem decrescente de Grau de Preferência Alimentar (GPA, foram: insetos alóctones, restos de insetos, material vegetal alóctone, sementes de Croton urucurana, insetos autóctones, sedimentos, material vegetal autóctone, escamas, ovócitos e aracnídeos. Sementes de Croton urucurana ocorreram no verão, época de cheia dos rios. Sugere-se que Astyanax altiparanae seja um dispersor secundário das sementes de Croton urucurana, sendo que a intensidade e a efetividade dessa dispersão devem, ainda, ser investigadasThis work characterized the feeding of Astyanax altiparanae in the sub-basin of Corumbataí river and in the basin of Jacaré-pepira river with a focus on the ingestion of Croton urucurana seeds. The food items of Astyanax altiparanae were, in decreasing APD (Alimentary Preference Degree order: allochthonous insects, allochthonous plant material, Croton urucurana seeds, autochthonous insects, sediments, autochthonous plant material, scales, oocytes and arachnidans. Croton urucurana seeds occurred during the summer, in the flood period. Lambari, Astyanax altiparanae, could be a secondary disperser of Croton urucurana seeds, however, the intensity and effectiveness of this dispersion may be still investigated

  2. A preliminary assessment of the effectiveness of the Mesoamerican Biological Corridor for protecting potential Baird's tapir (Tapirus bairdii) habitat in Southern Mexico.

    Science.gov (United States)

    Mendoza, Eduardo; Fuller, Trevon L; Thomassen, Henri A; Buermann, Wolfgang; Ramírez-Mejía, Diana; Smith, Thomas B

    2013-03-01

    Baird's tapir (Tapirus bairdii) is one of the most emblematic mammals of Mesoamerica, but like other large-bodied animals, it is facing an increasing risk of extinction due primarily to habitat loss. Mexico's 'ortion of the Mesoamerican Biological Corridor (MBC-M) is located in one of the main strongholds for Bairds tapir. To assess the MBC-M's effectiveness for tapir conservation, we estimated the distribution of the species' potential habitat by applying 2 modelling approaches (random forest and Maxent) to a set of uncorrelated environmental variables and a 157-point presence dataset. We calculated the extent of tapir habitat in within the MBC-M and modelled new corridors and conservation areas, which we compared to the MBC-M. Moreover, we assessed deforestation patterns in the region. Twenty-seven percent of highly suitable tapir habitat occurred in protected areas, 15% in corridors and 58.3% was outside the MBC-M and associated reserves. The spatial configuration of the MBC-M was partially concordant with the modelled set of conservation areas and corridors. The main dissimilarity was that the modelled corridors traversed forests in Belize and Guatemala to connect conservation areas. Analyses of deforestation since 1993 and human population density in the vicinity of the MBC-M indicated that future conservation efforts should give particular attention to the Montes Azules-El Triunfo Corridor due to greater habitat threat. The MBC-M has a great potential to play a prominent role in the conservation of tapir habitat but there is an urgent need to implement management plans that reinforce and complement this conservation initiative.

  3. Two - three loci control scleral ossicle formation via epistasis in the cavefish Astyanax mexicanus.

    Science.gov (United States)

    Lyon, Anastasia; Powers, Amanda K; Gross, Joshua B; O'Quin, Kelly E

    2017-01-01

    The sclera is the protective outer layer of the eye. In fishes, birds, and reptiles, the sclera may be reinforced with additional bony elements called scleral ossicles. Teleost fish vary in the number and size of scleral ossicles; however, the genetic mechanisms responsible for this variation remain poorly understood. In this study, we examine the inheritance of scleral ossicles in the Mexican tetra, Astyanax mexicanus, which exhibits both a cave morph and a surface fish morph. As these morphs and their hybrids collectively exhibit zero, one, and two scleral ossicles, they represent a microcosm of teleost scleral ossicle diversity. Our previous research in F2 hybrids of cavefish from Pachón cave and surface fish from Texas suggested that three genes likely influence the formation of scleral ossicles in this group through an epistatic threshold model of inheritance, though our sample size was small. In this study, we expand our sample size using additional hybrids of Pachón cavefish and Mexican surface fish to (1) confirm the threshold model of inheritance, (2) refine the number of genes responsible for scleral ossicle formation, and (3) increase our power to detect quantitative trait loci (QTL) for this trait. To answer these three questions, we scored surface fish and cavefish F2 hybrids for the presence of zero, one, or two scleral ossicles. We then analyzed their distribution among the F2 hybrids using a chi-square (χ2) test, and used a genetic linkage map of over 100 microsatellite markers to identify QTL responsible for scleral ossicle number. We found that inheritance of scleral ossicles follows an epistatic threshold model of inheritance controlled by two genes, which contrasts the three-locus model estimated from our previous study. Finally, the combined analysis of hybrids from both crosses identified two strong QTL for scleral ossicle number on linkage groups 4.2 and 21, and a weaker QTL on linkage group 4.1. Scleral ossification remains a complex

  4. The forebrain of the blind cave fish Astyanax hubbsi (Characidae). I. General anatomy of the telencephalon.

    Science.gov (United States)

    Riedel, G

    1997-01-01

    This paper presents a survey of the cell groups in the telencephalon of the teleost Astyanax hubbsi, based on series of transverse sections stained with the Nissl-Klüver-Barrera and Bodian procedures. The work was conducted for two reasons. Firstly, it was intended to determine the contribution of the forebrain of blind cave fish to certain forms of behavior. An understanding of the anatomy of the telencephalic organization is essential for such a neuroethological approach. The second purpose was to provide the cytoarchitectural basis for the experimental analysis of the fiber connectivity of the telencephalon of A. hubbsi. Furthermore, information about the forebrain of characids is widely lacking, and this study may thus provide important knowledge about the cellular organization of characid forebrains for comparative anatomists. The brain of A. hubbsi is slender and elongated. Both optic nerves and optic tectum are reduced. Three longitudinal sulci-s. ypsiliformis, s. externus and s. limitans telencephali-can be distinguished in the telencephalon. A fiber lamina reaching from the s. externus to the s. limitans telencephali separates the area dorsalis (D) from the area ventralis telencephali (V). The two hemispheres are connected by fibers decussating in the anterior commissure. Although cross sections revealed no distinct fiber laminae between cytoarchitectonic components, 17 cell masses could be delineated: ten of these belong to D, seven to V. The topological analysis yielded the following results. The dorsal telencephalon D consists of three longitudinal columns, termed pars medialis (Dm), pars dorsalis and centralis (Dd and Dc) considered together, and par lateralis (Dl), which converge into a uniform posterior part (Dp). The columns can be divided into several subregions: Dm1 and Dm2, as well as Dlv and Dld, precommissurally, Dm3 and Dm4 postcommisurally. At polus posterior levels nucleus tenia can be identified. The ventral telencephalon (V) is arranged

  5. Reproductive traits and population structure of Astyanax aeneus (Characiformes: Characidae) from a subtropical river in Mexico.

    Science.gov (United States)

    Trujillo-Jiménez, Patricia; Sedeño-Diaz, Jacinto Elias; Camargo, Julio A; López-López, Eugenia

    2013-06-01

    Champotón River is an unknown area within the Mesoamerican hotspot in Southestern México. Reproductive traits and population structure of Astyanax aeneus were analyzed along an environmental gradient of the upper, middle and lower sections of the river, where diverse environmental factors were recorded. For this, nets were cast for 1 h at each site and A. aeneus were collected from all sections with sweep nets (5 and 10 m long by 5 m deep, 0.03m mesh size) and a casting net (0.05m mesh size). At each study site and campaign, a total of 80 specimens (in average) were collected and were fixed in 10% formaldehyde for further analysis. Population structure by size was analyzed for each study site, based on the relative frequencies by standard length classes. The length-weight relationship was determined, and the identification of gonadal developmental stages, reproductive period, size at first sexual maturity, relative fecundity, sex ratio and somatic indexes (gonadosomatic, hepatosomatic and Fulton's condition factor) were also assessed. Seven size classes were found in the upper and middle sections, and nine downstream, with seasonal and spatial pattern in size-class frequency distribution. Size at first maturity was 45.7mm for females and 40.8mm for males. The maximum relative fecundity was recorded at the downstream site and was positively correlated with body weight and standard length. Sex ratio (1.8:1 males: females) differed significantly from expected values (1:1). Gonadosomatic index scores indicated that the reproductive period of this species in the Champot6n River was from April to July, during the warm and wet season. Hepatosomatic index was negatively correlated with the Gonadosomatic index, evidencing transfer of energy from the liver towards gamete production. This strategy enabled A. aeneus to maintain robustness during the study period with tiny changes in condition factor. A. aeneus in the Champotón River, as opposed to South American river

  6. Reproductive traits and population structure of Astyanax aeneus (Characiformes: Characidae from a subtropical river in Mexico

    Directory of Open Access Journals (Sweden)

    Patricia Trujillo-Jiménez

    2013-06-01

    Full Text Available Champotón River is an unknown area within the Mesoamerican hotspot in Southestern México. Reproductive traits and population structure of Astyanax aeneus were analyzed along an environmental gradient of the upper, middle and lower sections of the river, where diverse environmental factors were recorded. For this, nets were cast for 1h at each site and A. aeneus were collected from all sections with sweep nets (5 and 10m long by 5m deep, 0.03m mesh size and a casting net (0.05m mesh size. At each study site and campaign, a total of 80 specimens (in average were collected and were fixed in 10% formaldehyde for further analysis. Population structure by size was analyzed for each study site, based on the relative frequencies by standard length classes. The length-weight relationship was determined, and the identification of gonadal developmental stages, reproductive period, size at first sexual maturity, relative fecundity, sex ratio and somatic indexes (gonadosomatic, hepatosomatic and Fulton’s condition factor were also assessed. Seven size classes were found in the upper and middle sections, and nine downstream, with seasonal and spatial pattern in size-class frequency distribution. Size at first maturity was 45.7mm for females and 40.8mm for males. The maximum relative fecundity was recorded at the downstream site and was positively correlated with body weight and standard length. Sex ratio (1.8:1 males: females differed significantly from expected values (1:1. Gonadosomatic index scores indicated that the reproductive period of this species in the Champotón River was from April to July, during the warm and wet season. Hepatosomatic index was negatively correlated with the Gonadosomatic index, evidencing transfer of energy from the liver towards gamete production. This strategy enabled A. aeneus to maintain robustness during the study period with tiny changes in condition factor. A. aeneus in the Champotón River, as opposed to South

  7. Two – three loci control scleral ossicle formation via epistasis in the cavefish Astyanax mexicanus

    Science.gov (United States)

    Lyon, Anastasia; Powers, Amanda K.; Gross, Joshua B.; O’Quin, Kelly E.

    2017-01-01

    The sclera is the protective outer layer of the eye. In fishes, birds, and reptiles, the sclera may be reinforced with additional bony elements called scleral ossicles. Teleost fish vary in the number and size of scleral ossicles; however, the genetic mechanisms responsible for this variation remain poorly understood. In this study, we examine the inheritance of scleral ossicles in the Mexican tetra, Astyanax mexicanus, which exhibits both a cave morph and a surface fish morph. As these morphs and their hybrids collectively exhibit zero, one, and two scleral ossicles, they represent a microcosm of teleost scleral ossicle diversity. Our previous research in F2 hybrids of cavefish from Pachón cave and surface fish from Texas suggested that three genes likely influence the formation of scleral ossicles in this group through an epistatic threshold model of inheritance, though our sample size was small. In this study, we expand our sample size using additional hybrids of Pachón cavefish and Mexican surface fish to (1) confirm the threshold model of inheritance, (2) refine the number of genes responsible for scleral ossicle formation, and (3) increase our power to detect quantitative trait loci (QTL) for this trait. To answer these three questions, we scored surface fish and cavefish F2 hybrids for the presence of zero, one, or two scleral ossicles. We then analyzed their distribution among the F2 hybrids using a chi-square (χ2) test, and used a genetic linkage map of over 100 microsatellite markers to identify QTL responsible for scleral ossicle number. We found that inheritance of scleral ossicles follows an epistatic threshold model of inheritance controlled by two genes, which contrasts the three-locus model estimated from our previous study. Finally, the combined analysis of hybrids from both crosses identified two strong QTL for scleral ossicle number on linkage groups 4.2 and 21, and a weaker QTL on linkage group 4.1. Scleral ossification remains a complex

  8. The genus Squamanita

    NARCIS (Netherlands)

    Bas, C.

    1965-01-01

    By transferring Cystoderma paradoxum Smith & Sing. and Vaginata umbonata Sumst. to the genus Squamanita and the description of the new species, S. pearsonii, the number of species of that genus is raised from two to five. In addition two more species of Squamanita are provisionally described. An

  9. The genus Bipolaris.

    Science.gov (United States)

    Manamgoda, D S; Rossman, A Y; Castlebury, L A; Crous, P W; Madrid, H; Chukeatirote, E; Hyde, K D

    2014-09-01

    The genus Bipolaris includes important plant pathogens with worldwide distribution. Species recognition in the genus has been uncertain due to the lack of molecular data from ex-type cultures as well as overlapping morphological characteristics. In this study, we revise the genus Bipolaris based on DNA sequence data derived from living cultures of fresh isolates, available ex-type cultures from worldwide collections and observation of type and additional specimens. Combined analyses of ITS, GPDH and TEF gene sequences were used to reconstruct the molecular phylogeny of the genus Bipolaris for species with living cultures. The GPDH gene is determined to be the best single marker for species of Bipolaris. Generic boundaries between Bipolaris and Curvularia are revised and presented in an updated combined ITS and GPDH phylogenetic tree. We accept 47 species in the genus Bipolaris and clarify the taxonomy, host associations, geographic distributions and species' synonymies. Modern descriptions and illustrations are provided for 38 species in the genus with notes provided for the other taxa when recent descriptions are available. Bipolaris cynodontis, B. oryzae, B. victoriae, B. yamadae and B. zeicola are epi- or neotypified and a lectotype is designated for B. stenospila. Excluded and doubtful species are listed with notes on taxonomy and phylogeny. Seven new combinations are introduced in the genus Curvularia to accomodate the species of Bipolaris transferred based on the phylogenetic analysis. A taxonomic key is provided for the morphological identification of species within the genus.

  10. The genus Idertia (Ochnaceae)

    NARCIS (Netherlands)

    Sosef, M.S.M.

    2013-01-01

    Background and aims - The genus Idertia belongs to the subfamily Ochnoideae, tribe Ochneae, subtribe Ouratinae. This paper aims at a full taxonomic revision and a critical evaluation of the taxonomic position of the genus along with its diagnostic characters. Methods - All characters are studied usi

  11. Construction of bacterial artificial chromosome libraries for the Lake Malawi cichlid (Metriaclima zebra), and the blind cavefish (Astyanax mexicanus).

    Science.gov (United States)

    Di Palma, Federica; Kidd, Celeste; Borowsky, Richard; Kocher, Thomas D

    2007-01-01

    Teleost fishes have become important models for studying the evolution of the genetic mechanisms of development. A key resource for comparative genomics and positional cloning are large-insert libraries constructed in bacterial artificial chromosomes. We have constructed bacterial artificial chromosome libraries for two species of teleost fish that are important models for the study of developmental evolution. Metriaclima zebra is one of several hundred closely related, morphologically diverse, haplochromine cichlids which have evolved over the last one million years in Lake Malawi, East Africa. The Mexican tetra, Astyanax mexicanus, is well known for adaptations related to the recent evolution of blind cave-dwelling forms. Clones and high-density filters for each library are available to the scientific community through the Hubbard Center for Genome Studies.

  12. Discrimination of Astyanax altiparanae (Characiformes, Characidae) populations by applying Fourier transform-infrared photoacoustic spectroscopy in the fish scales

    Science.gov (United States)

    de Almeida, F. S.; Santana, C. A.; Lima, D. M. V.; Andrade, L. H. C.; Súarez, Y. R.; Lima, S. M.

    2016-05-01

    Astyanax altiparanae fish species is considered very generalist and opportunist, occupying different types and sizes of environments. This characteristic turns it very appropriate as bioindicator or biomarked. Therefore, in this work, A. altiparanae fish species was used to identify populations by using the Fourier transform infrared spectroscopy directly in its scales. The discriminant analysis applied in the infrared spectra demonstrated a significant differentiation among the analyzed populations, with the first and second canonical roots explain together 100% of the data variation. The obtained results were correlated with environmental descriptors and diet of fishes, and a better agreement was obtained when spectroscopic data were compared with the composition of food present in the fish stomachs. However, this study indicates that the combination of infrared absorption spectroscopy with discriminant analysis is a very appropriate methodology to be used in fish scales as bioindicator for intraspecific study.

  13. Evidence of the differentiated structural arrangement of constitutive heterochromatin between two populations of Astyanax scabripinnis (Pisces, Characidae

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    Monique Mantovani

    2004-01-01

    Full Text Available The composition of heterochromatin classes along the chromosomes of specimens from two populations of the fish Astyanax scabripinnis was examined using fluorescence banding with GC- and AT-DNA specific fluorochromes and fluorescence in situ hybridization (FISH with an AT-rich satellite DNA (As51 probe. For the pericentromeric heterochromatin blocks neither GC/AT-DNA specific fluorochromes nor the FISH technique produce any response with chromosomes from either of the populations. On the other hand, the telomeric distal heterochromatin blocks of both populations fluoresced when the FISH technique was applied but showed distinct responses after GC-specific fluorochrome treatments, leading us to propose different structural arrangements of the FISH-positive heterochromatins. Such differences in chromosome banding patterns together with other karyotypic differences suggest differentiation of these populations at taxonomic level.

  14. Use of Muscular Cholinesterase of Astyanax bifasciatus (Teleostei, Characidae) as a Biomarker in Biomonitoring of Rural Streams.

    Science.gov (United States)

    Nimet, Jardel; Guimarães, Ana Tereza Bittencourt; Delariva, Rosilene Luciana

    2017-08-01

    Cholinesterase (ChE) activity was measured in Astyanax bifasciatus maintained in controlled conditions. Muscle ChE activity of individuals collected in field conditions in two seasons was compared among specimens collected in seven streams (forest and rural) of the lower Iguaçu river basin in association with physical, chemical, pesticides and biological factors. Significant differences in muscle ChE activity between control fish and fish collected in streams in both seasons were found, with higher activity in natural conditions. This the first time that differences in muscle ChE activity have been found among fish collected from different streams, suggesting synergism among multiple factors (e.g. temperature, pH, animal weight) and ecological attributes (richness and abundance) as influencing the variation in biomarkers. It is necessary to evaluate the quality of aquatic environments for a more accurate biomonitoring approach.

  15. Diet of Astyanax paranae (Characidae) in streams with different riparian land covers in the Passa-Cinco River basin, southeastern Brazil

    OpenAIRE

    Anderson Ferreira; Pedro Gerhard; CYRINO,JOSÉ E.P.

    2012-01-01

    An analysis of the diet of Astyanax paranae Eigenmann, 1914 in nine streams located in the Passa-Cinco River basin (upper Parana River system) was performed to investigate the feeding habits of this species, check for possible spatial variations in diet and to investigate the influence of riparian vegetation in the composition of the diet. Stomach contents of 243 specimens were analyzed by the methods of relative frequency of occurrence and volume, and the diet was characterized by the alimen...

  16. Cytogenetic analysis in the incertae sedis species Astyanax altiparanae Garutti and Britzki, 2000 and Hyphessobrycon eques Steindachner, 1882 (Characiformes, Characidae) from the upper Paraná river basin

    Science.gov (United States)

    Martinez, Emanuel R. M.; Alves, Anderson L.; Silveira, Sara M.; Foresti, Fausto; Oliveira, Claudio

    2012-01-01

    Abstract Cytogenetic analyses were accomplished in two populations of Astyanax altiparanae Garutti & Britzki, 2000 and one population of Hyphessobrycon eques Steindachner, 1882, considered incertae sedis in Characidae family. Two populations of Astyanax altiparanae (Mogi-Guaçu and Tietê rivers) presented 2n=50, with the same karyotype formula: 6M+12SM+20ST+12A (FN=88). Hyphessobrycon eques from Capivara river presented 2n=52 and karyotype formula 14M+16SM+4ST+18A (FN=86). In each karyotype, the nucleolus organizer regions were detected at the end of the short arm of a single medium-sized subtelocentric chromosome. The Chromomycin A3 (CMA3) marking is coincident for the NORs in chromosomes of the two species and present additionally in two different chromosomes of Astyanax altiparanae thus showinginterpopulation differences in this species. In Hyphessobrycon eques, weak heterochromatic blocks in the position of centromeres and telomeres of most chromosomes and negative C-banding for the NOR bearing chromosome were visualized. The obtained results contribute both to the understanding of karyotype evolution of these species and to the clarifying their phylogenetic relationships. PMID:24260651

  17. OCCURRENCE OF Henneguya sp. (THÉLOHAN, 1892 IN THE BLOOD OF Astyanax fasciatus (CUVIER, 1819 IN A STREAM OF THE MURIAÉ RIVER BASIN IN ITAPERUNA, RJ

    Directory of Open Access Journals (Sweden)

    Pedro Henrique CAETANO

    2015-12-01

    Full Text Available Esse estudo reporta a presença de Henneguya sp. no sangue de Astyanax fasciatus de ambiente natural, em um córrego da sub-bacia do rio Muriaé, pertencente a bacia do rio do Paraíba do Sul de Itaperuna, estado do Rio de Janeiro, Brasil. Oito coletas foram realizadas em outubro de 2009 e setembro de 2010, com 45 dias de intervalo, em cada coleta foram capturados dez espécimes de Astyanax fasciatus dando um total de 80 lâminas de sangue. Esse estudo relata a presença de Henneguya sp. em duas espécimes coletadas em novembro de 2009. Essa baixa incidência de parasitas ocorreu porque o gênero Henneguya já foi registrado em vários órgãos de espécies do gênero Astyanax. Embora os filamentos branquiais sejam de locais com maior tropismo e alta prevalência, não foram encontrados registros na literatura de parasitas com esse gênero no sangue de peixes.

  18. Morphological and molecular diversity of Lake Baikal candonid ostracods, with description of a new genus

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    Ivana Karanovic

    2017-07-01

    Full Text Available Uncoupling between molecular and morphological evolution is common in many animal and plant lineages. This is especially frequent among groups living in ancient deep lakes, because these ecosystems promote rapid morphological diversification, and has already been demonstrated for Tanganyika cychlid fishes and Baikal amphipods. Ostracods are also very diverse in these ecosystems, with 107 candonid species described so far from Baikal, majority of them in the genera Candona Baird, 1845 and Pseudocandona Kaufmann, 1900. Here we study their morphological and molecular diversity based on four genes (two nuclear and two mitochondrial, 10 species from the lake, and 28 other species from around the world. The results of our phylogenetic analysis based on a concatenated data set, along with sequence diversity, support only two genetic lineages in the lake and indicate that a majority of the Baikal Candona and Pseudocandona species should be excluded from these genera. We describe a new genus, Mazepovacandona gen. n., to include five Baikal species, all redescribed here. We also amend the diagnosis for the endemic genus Baicalocandona Mazepova, 1972 and redescribe two species. Our study confirms an exceptional morphological diversity of Lake Baikal candonids and shows that both Baikal lineages are closely related to Candona, but only distantly to Pseudocandona.

  19. Comentários sobre a distribuição geográfica de Astyanax altiparanae Garutti & Britski, 2000 (Osteichthyes, Characidae na bacia do rio Iguaçu Astyanax altiparanae Garutti & Britski, 2000 (Osteichthyes, Characidae in the Iguaçu River basin

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    Weferson Júnio da Graça

    2002-05-01

    Full Text Available Garutti (1995 fez a revisão de algumas espécies de Astyanax (Osteichthyes, Characidae e aquela, conhecida como “tambiú” na bacia do alto rio Paraná, anteriormente identificada como Astyanax bimaculatus, foi considerada nova e posteriormente descrita por Garutti & Britski (2000 como Astyanax altiparanae (Pisces, Characiformes. Naquela oportunidade, entretanto, não foram analisados exemplares da bacia do rio Iguaçu. Esse afluente do rio Paraná apresenta um alto grau de endemismo em sua ictiofauna devido ao isolamento geográfico causado pelas cataratas situadas próximo à sua foz. No entanto, muitas dúvidas relacionadas ao status específico da população da bacia do Iguaçu, também chamada de A. bimaculatus antes dos trabalhos de Garutti, permaneceram. Com o escopo de verificar se a população do Iguaçu era da espécie A. altiparanae, comparamos espécimes das duas bacias e concluímos que elas pertencem à mesma espécie, sendo, portanto, sua distribuição geográfica ampliada.Garutti (1995 made a revision of some Astyanax (Osteichthyes, Characidae species and the species called tambiú from the upper Paraná River basin, formerly identified as Astyanax bimaculatus, was considered new. Garutti & Britski (2000 later described it as Astyanax altiparanae (Pisces, Characiformes. However, they did not analyze specimens from the Iguaçu River basin at that time. The Iguaçu River, affluent to the Paraná River, has a high degree of endemism in its ichthyofauna because of the geographic isolation caused by the falls near its mouth. Thus, there were still many doubts regarding the specific status of the population from the Iguaçu River basin, also called A. bimaculatus before Garutti’s studies. To verify if the population from the Iguaçu River belongs to the A. altiparanae species, we compared specimens from both basins and concluded that they belong to the same species, widening their geographic distribution.

  20. Light microscopy and ultrastructure ight of the liver of Astyanax altiparanae Garutti and Britski, 2000 (Teleostei, Characidae = Histologia e ultraestrutura do fígado de Astyanax altiparanae Garutti e Britski, 2000 (Teleostei, Characidae

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    Bruno Bertolucci

    2008-01-01

    Full Text Available Livers of thirty specimens of Astyanax altiparanae obtained from a commercial fish farm were subjected to light and transmission electron microscopy, in order to describe the hepatic parenchyma and the intrahepatic exocrine pancreatic tissue. Anatomically, theliver showed only three hepatic lobes. Histological analysis demonstrated that the hepatocytes were spread out as anastomotic cords, arranged in two cellular layers and surrounded by sinusoids. The intrahepatic exocrine pancreatic tissue exhibited an acinararrangement and was diffused in the hepatic parenchyma. Ultrastructural analysis showed that the hepatocytes had a rounded nucleus and a rough endoplasmatic reticulum, with a parallel disposition to the nuclear membrane. The exocrine pancreatic cells showed secretion granules at the apical portion, and the rough endosplasmatic reticulum was concentrically distributed.Fígados de 30 exemplares de Astyanax altiparanae, obtidos de pesqueiros, foram submetidos à microscopia de luz e à microscopia eletrônica de transmissão para descrição do parênquima hepático e do tecido pancreático exócrino intrahepático. Anatomicamente, o fígado apresenta somente três lobos hepáticos. A análise histológica demonstra que os hepatócitos se encontram arranjados na forma de cordões anastomosados, dispostos em duas camadas celulares, sendo que estes estão cercados por sinusóides. O tecido pancreático exócrino intra-hepático apresenta arranjo acinar difuso pelo parênquima hepático. A análise ultraestrutural demonstra que os hepatócitos possuem um núcleo arredondado e retículo endoplasmático rugoso, com disposição paralela à membrana nuclear. As células pancreáticas exócrinas apresentam grânulos de secreção na porção apical e retículo endoplasmático rugoso com distribuição concêntrica.

  1. A new species of Auriculostoma (Trematoda: Allocreadiidae) from the intestine of Brycon guatemalensis (Characiformes: Bryconidae) from the Usumacinta River Basin, Mexico, based on morphology and 28S rDNA sequences, with a key to species of the genus.

    Science.gov (United States)

    Hernández-Mena, David Iván; Lynggaard, Christina; Mendoza-Garfias, Berenit; DE León, Gerardo Pérez-Ponce

    2016-11-22

    We describe a new species of Auriculostoma Scholz, Aguirre-Macedo & Choudhury, 2004 based on several sources of information including morphology (light and scanning electron microscopy [SEM]), sequences of two nuclear genes, host association, and geographical distribution. Morphologically, the new species most closely resembles Auriculostoma astyanace Scholz, Aguirre-Macedo & Choudhury, 2004, but differs by having deeply lobated testes and cirrus-sac extending posteriorly to seminal receptacle level. Auriculostoma lobata n. sp. can be readily distinguished from all the other congeners by the combination of the following characters: testes located in tandem, testes deeply lobated, and larger body size. A phylogenetic analysis using 28S rDNA sequences along with those available for other allocreadiid trematodes, revealed that the new species is a sister taxon of A. astyanace, a species described from the banded astyanax, Astyanax fasciatus (Cuvier) in Nicaragua. Auriculostoma totonacapanensis Razo-Mendivil, Mendoza-Garfias, Pérez-Ponce de León & Rubio-Godoy, 2014 from the Mexican tetra, Astyanax mexicanus (De Filippi) in Mexico is the sister taxon of A. astyanace plus the new species. Genetic divergence levels for the 28S rDNA and ITS2 were estimated among the Middle-American species of Auriculostoma infecting characiforms. The validity of the new species is then established by reliable morphological differences, its host association to bryconids (Brycon guatemalensis Regan), restricted geographical distribution (Usumacinta and Lacantun River basins), and genetic divergence levels, albeit relatively low. A morphometric comparison between the new species and the other seven congeneric species was undertaken and, in addition, a taxonomic key to identify the species contained in the genus Auriculostoma, widely distributed across the Americas, is provided.

  2. The genus Cladosporium

    NARCIS (Netherlands)

    Bench, K.; Braun, U.; Groenewald, J.Z.; Crous, P.W.

    2012-01-01

    A monographic revision of the hyphomycete genus Cladosporium s. lat. (Cladosporiaceae, Capnodiales) is presented. It includes a detailed historic overview of Cladosporium and allied genera, with notes on their phylogeny, systematics and ecology. True species of Cladosporium s. str. (anamorphs of Dav

  3. The genus Lagenophora (Compositae)

    NARCIS (Netherlands)

    Cabrera, Angel L.

    1966-01-01

    The genus Lagenophora was first described by Cassini under the name Lagenifera (in Bull. Soc. Philomat. 12, 1816, 199) with the following diagnosis: ‘Ce genre, de la tribus des astérées, comprend le calendula magellanicá, Willd. et le bellis stipitata, Labill. Son principal caractère reside dans la

  4. The genus Cladosporium

    NARCIS (Netherlands)

    Bench, K.; Braun, U.; Groenewald, J.Z.; Crous, P.W.

    2012-01-01

    A monographic revision of the hyphomycete genus Cladosporium s. lat. (Cladosporiaceae, Capnodiales) is presented. It includes a detailed historic overview of Cladosporium and allied genera, with notes on their phylogeny, systematics and ecology. True species of Cladosporium s. str. (anamorphs of

  5. The genus Lagenophora (Compositae)

    NARCIS (Netherlands)

    Cabrera, Angel L.

    1966-01-01

    The genus Lagenophora was first described by Cassini under the name Lagenifera (in Bull. Soc. Philomat. 12, 1816, 199) with the following diagnosis: ‘Ce genre, de la tribus des astérées, comprend le calendula magellanicá, Willd. et le bellis stipitata, Labill. Son principal caractère reside dans la

  6. The genus Faradaya (Labiatae)

    NARCIS (Netherlands)

    Kok, de R.P.J.; Mabberley, D.J.

    1999-01-01

    A revision of the genus Faradaya F. Muell. (Labiatae) is presented with taxonomic history, keys, full descriptions, distribution maps and ecological and ethnobotanical notes. Only three species are recognised: F. amicorum (Seem.) Seem., F. lehuntei (Home ex Baker) A.C. Sm. and F. splendida F. Muell.

  7. The amphipod genus Acidostoma

    NARCIS (Netherlands)

    Dahl, E.

    1964-01-01

    The genus Acidostoma was established by Lilljeborg (1865, p. 24) to receive Anonyx obesus Sp. Bate (1862, p. 74). Afterwards two further species have been added, viz. A. laticorne G. O. Sars (1879, p. 440) and A. nodiferum Stephensen (1923, p. 40). In the present paper it will be shown that A. latic

  8. Spatial and temporal biomarkers responses of Astyanax jacuhiensis (Cope, 1894(Characiformes: Characidae from the middle rio Uruguai, Brazil

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    Vania Lucia Loro

    Full Text Available Due to intense agricultural activity in the rio Uruguai (South Brazil, there is the potential for aquatic contamination by agrochemicals. In this region, there are many reservoirs to meet the water demand for rice fields, forming lentic environments. In line with this information, the aim of this study was to show a comparative analysis of some biomarkers, such as lipid peroxidation (TBARS, gluthatione S-transferase (GST, non-protein thiols (NPSH, amino acids (AA and piscine micronucleus tests (MNE in Astyanax jacuhiensis from lentic and lotic environments in the middle rio Uruguai region, comparing warm and cold seasons. Eight pesticides were found in water samples, with propoxur having the highest concentration found in both environments and seasons. Fish from the warm season showed higher levels of biochemical biomarkers, and fish from the cold season showed higher levels of MNE and AA. TBARS and AA presented higher levels in fish from the river, while GST, NPSH, MNE and AA presented higher levels in fish from dams. These environments have different characteristics in terms of redox potential, aeration, sedimentation, trophic structure, agrochemicals input and others, which may affect the physiological and biochemical responses of fish in against adverse situations.

  9. The sensitivity of lateral line receptors and their role in the behavior of Mexican blind cavefish (Astyanax mexicanus)

    Science.gov (United States)

    Yoshizawa, Masato; Jeffery, William R.; van Netten, Sietse M.; McHenry, Matthew J.

    2014-01-01

    The characid fish species Astyanax mexicanus offers a classic comparative model for the evolution of sensory systems. Populations of this species evolved in caves and became blind while others remained in streams (i.e. surface fish) and retained a functional visual system. The flow-sensitive lateral line receptors, called superficial neuromasts, are more numerous in cavefish than in surface fish, but it is unclear whether individual neuromasts differ in sensitivity between these populations. The aims of this study were to determine whether the neuromasts in cavefish impart enhanced sensitivity relative to surface fish and to test whether this aids their ability to sense flow in the absence of visual input. Sensitivity was assessed by modeling the mechanics and hydrodynamics of a flow stimulus. This model required that we measure the dimensions of the transparent cupula of a neuromast, which was visualized with fluorescent microspheres. We found that neuromasts within the eye orbit and in the suborbital region were larger and consequently about twice as sensitive in small adult cavefish as in surface fish. Behavioral experiments found that these cavefish, but not surface fish, were attracted to a 35 Hz flow stimulus. These results support the hypothesis that the large superficial neuromasts of small cavefish aid in flow sensing. We conclude that the morphology of the lateral line could have evolved in cavefish to permit foraging in a cave environment. PMID:24265419

  10. The lens has a specific influence on optic nerve and tectum development in the blind cavefish Astyanax.

    Science.gov (United States)

    Soares, Daphne; Yamamoto, Yoshiyuki; Strickler, Allen G; Jeffery, William R

    2004-01-01

    We used the teleost Astyanaxmexicanus to examine the role of the lens in optic nerve and tectum development. This speciesis unusually suited for studies of nervous system development and evolution because of its two extant forms: an eyed surface dwelling (surface fish) and several blind cave dwelling (cavefish) forms. Cavefish embryos initially form eye primordia, but the lens eventually dies by apoptosis, then the retina ceases to grow, and finally the degenerating eyes sink into the orbits. Transplantation of an embryonic surface fish lens into a cavefish optic cup restores eye development. We show here that retinal nerve fibers are formed and project to the optic tectum in cavefish embryos. In adult cavefish that have completed lens degeneration, however, the number of retinal axons in the optic nerve is substantially reduced compared to surface fish. The presumptive brain domains of embryonic cavefish are not altered relative to surface fish based on expression of the regional marker genes Pax6, Pax2.1, and engrailed2. In contrast, the adult cavefish brain is elongated, the optic tectum is diminished in volume, and the number of tectal neurons is reduced relative to surface fish. Unilateral transplantation of an embryonic surface fish lens into a cavefish optic cup increases the size of the optic nerve, the number of retinotectal projections from the restored eye, and the volume and neuronal content of the contralateral optic tectum. The results suggest that the lens has a specific influence on optic nerve and tectum development during eye growth in Astyanax.

  11. Prox 1 in eye degeneration and sensory organ compensation during development and evolution of the cavefish Astyanax.

    Science.gov (United States)

    Jeffery, W; Strickler, A; Guiney, S; Heyser, D; Tomarev, S

    2000-05-01

    We have investigated expression of the homeobox gene Prox 1 during eye degeneration and sensory organ compensation in cavefish embryos. The teleost Astyanax mexicanus consists of sighted surface-dwelling forms (surface fish) and several populations of blind cave-dwelling forms (cavefish), which have evolved independently. Eye formation is initiated during cavefish development, but the lens vesicle undergoes apoptosis, and the eye subsequently arrests and degenerates. The requirement of Prox 1 for lens fiber differentiation and gamma-crystallin expression in the mouse suggests that changes in the expression of this gene could be involved in cavefish eye degeneration. Surface fish and cavefish embryos stained with a Prox 1 antibody showed Prox 1 expression in the lens, neuroretina, myotomes, heart, hindbrain, and gut, as reported in other vertebrates. We found that Prox 1 expression is not altered during cavefish lens development. Prox 1 protein was detected in the lens vesicle as soon as it formed and persisted until the time of lens degeneration in each cavefish population. The cavefish lens vesicle was also shown to express a gamma-crystallin gene, suggesting that Prox 1 is functional in cavefish lens development. In addition to the tissues described above, Prox 1 is expressed in developing taste buds and neuromasts in cavefish, which are enhanced to compensate for blindness. It is concluded that the Prox 1 gene is not involved in lens degeneration, but that expansion of the Prox 1 expression domain occurs during taste bud and neuromast development in cavefish.

  12. Cytogenetic analysis in the neotropical fish Astyanax goyacensis Eigenmann, 1908 (Characidae, incertae sedis): karyotype description and occurrence of B microchromosomes

    Science.gov (United States)

    2013-01-01

    Background B chromosomes, also known as supernumerary or accessory chromosomes, are additional chromosomes over the standard complement found in various groups of plants and animals. We investigated the presence of, and characterized, supernumerary microchromosomes in Astyanax goyacensis using classical and molecular cytogenetic methods. Findings Three specimens possessed 2n = 50 chromosomes (8m + 26sm + 8st + 8a), and two specimens contained 1 to 9 additional B microchromosomes varying intra- and inter-individually. Chromosome painting with a B chromosome-specific probe yielded signals for several B microchromosomes, with one exhibiting no markings. Acrocentric chromosomes of the standard complement were also painted. Fluorescence in situ hybridization (FISH) using ribosomal probes located two chromosome pairs carrying 18S rDNA marked on the short arm, and one pair carrying 5S rDNA with pericentromeric markings. One chromosome was observed in synteny with 18S cistrons. Conclusion These data contribute to knowledge of the karyotype evolution, the origin of B chromosomes, and to an understanding of the functionality of rDNA. PMID:24192310

  13. Morphology of the urogenital papilla and its component ducts in Astyanax altiparanae Garutti & Britski, 2000 (Characiformes: Characidae

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    Diógenes Henrique de Siqueira-Silva

    Full Text Available The histological description of the urogenital papilla is an important tool to comprehension of the reproductive mechanisms in fish, as well as a pre-requisite to germ cell transplantation in adult fish, besides to be a good biological indicator to environmental changes. Was performed the histological description of the urogenital papilla and its component ducts in the tetra Astyanax altiparanae. The genital and urinay ducts pass separately throughout most part of its extension, joining in a single duct before opening. In males this opening is asymmetric and seems to have double origin, being completely surrounded by striated muscle fibers, while in females it is symmetric and the muscle fibers does not surround it totally. Spermatic duct and oviduct undergo changes throughout their extension, mainly in the morphology of the surrounding epithelium. In the spermatic duct, squamous epithelial cells change to columnar and cuboid with possible secretory activity, close to testes. In the oviduct, anteriorly epithelial cells are also squamous, however, close to ovary there are lamellae composed by a pseudostratified epithelium with columnar and cuboid cells. The urinary duct is highly similar for both sexes presenting globoid cells, which description is known in mammals, however, rare in fish.

  14. Three sympatric karyomorphs in the fish Astyanax fasciatus (Teleostei, Characidae) do not seem to hybridize in natural populations

    Science.gov (United States)

    Ferreira-Neto, Maressa; Artoni, Roberto Ferreira; Vicari, Marcelo Ricardo; Moreira-Filho, Orlando; Camacho, Juan Pedro Martínez; Bakkali, Mohammed; de Oliveira, Claudio; Foresti, Fausto

    2012-01-01

    Abstract Ninety individuals of the characid fish Astyanax fasciatus (Cuvier, 1819) were collected at Água da Madalena stream (Botucatu, São Paulo, Brazil) and analyzed for diploid chromosome number 2n and karyotype composition as well as for the chromosomal location of the 5S and 18S ribosomal DNA (rDNA). Whereas no chromosome differences were associated with sex, three different karyomorphs with diploid chromosome numbers 2n=46, 2n=48 and 2n=50 were found. No intermediate 2n numbers were discovered. The 2n=50 karyomorph showed some differences in 18S rDNA location compared to the two other karyomorphs. Finally, all specimens with the 2n=46 karyomorph showed the presence of a partly heterochromatic macro supernumerary chromosome, which was absent in all individuals with the two other karyomorphs. All these results suggest that indviduals of the three different karyomorphs are not likely to hybridize in the examined populations. Our findings strongly suggest the presence of three separate species (sensu biological species concept) easily diagnosed on the basis of differences in the diploid chromosome numbers and other chromosomal markers. PMID:24260650

  15. Biomonitoring of genotoxicity using micronuclei assay in native population of Astyanax jacuhiensis (Characiformes: Characidae) at sites under petrochemical influence

    Energy Technology Data Exchange (ETDEWEB)

    Torres de Lemos, Clarice [Divisao de Biologia, Programa de Pesquisas Ambientais, Departamento de Laboratorios, Fundacao Estadual de Protecao Ambiental Henrique Luis Roessler (FEPAM), Avenida Dr. Salvador Franca, 1707, 90690-000, Porto Alegre, RS (Brazil)], E-mail: claricetl@fepam.rs.gov.br; Almeida Iranco, Fabio de; D' Avila de Oliveira, Nanci Cristina; Dornelles de Souza, Getulio [Divisao de Biologia, Programa de Pesquisas Ambientais, Departamento de Laboratorios, Fundacao Estadual de Protecao Ambiental Henrique Luis Roessler (FEPAM), Avenida Dr. Salvador Franca, 1707, 90690-000, Porto Alegre, RS (Brazil); Guimaraes Fachel, Jandyra Maria [Instituto de Matematica, Departamento de Estatistica, Universidade Federal do Rio Grande do Sul. Av. Bento Goncalves, 9500, 91509-9000, Porto Alegre, RS (Brazil)

    2008-11-15

    Bom Jardim brook is a small stream that flows through an area under the influence of a Petrochemical Complex, demanding control over its quality, so a genotoxic evaluation was performed. This study was conducted in situ, based on previous analysis on the same subject. These were performed both in vitro, with Salmonella typhimurium and human lymphocytes, and in vivo, using bioassays with fish exposed to water from the study area. The purpose of this research was to assess the quality of the aquatic environment and possible effects from petrochemical pollution to surrounding native populations. Micronuclei (MNE) and nuclear abnormalities (NA) frequencies in peripheral blood of Astyanax jacuhiensis, a native fish species collected from the study area, were used as biomarkers. Study period was from summer/99 to spring/2001, using samples obtained seasonally at two ponds upstream from the industrial area (BJN and BJPa) and two sites in Bom Jardim brook (BJ002 and BJ000), which are subject to Complex influence. MNE and NA frequencies found in individuals from BJ002 and BJ000 were similar, showing positive genotoxic responses related to control sites BJN and BJPa. No differential sensitivity could be verified for micronuclei induction between genders of A. jacuhiensis in the studied population. This study showed that sites subject to petrochemical influence were under higher genotoxic impact. Biomarkers adequacy to the case and the sensitivity of A. jacuhiensis for water monitoring could be also inferred.

  16. Three sympatric karyomorphs in the fish Astyanax fasciatus (Teleostei, Characidae do not seem to hybridize in natural populations

    Directory of Open Access Journals (Sweden)

    Maressa Ferreira-Neto

    2012-01-01

    Full Text Available Ninety individuals of the characid fish Astyanax fasciatus (Cuvier, 1819 were collected at Água da Madalena stream (Botucatu, São Paulo, Brazil and analyzed for diploid chromosome number 2n and karyotype composition as well as for the chromosomal location of the 5S and 18S ribosomal DNA (rDNA. Whereas no chromosome differences were associated with sex, three different karyomorphs with diploid chromosome numbers 2n=46, 2n=48 and 2n=50 were found. No intermediate 2n numbers were discovered. The 2n=50 karyomorph showed some differences in 18S rDNA location compared to the two other karyomorphs. Finally, all specimens with the 2n=46 karyomorph showed the presence of a partly heterochromatic macro supernumerary chromosome, which was absent in all individuals with the two other karyomorphs. All these results suggest that indviduals of the three different karyomorphs are not likely to hybridize in the examined populations. Our findings strongly suggest the presence of three separate species (sensu biological species concept easily diagnosed on the basis of differences in the diploid chromosome numbers and other chromosomal markers.

  17. Estimation of the dietary essential amino acid requirements of colliroja Astyanax fasciatus by using the ideal protein concept

    Directory of Open Access Journals (Sweden)

    Wilson Massamitu Furuya

    2015-11-01

    Full Text Available Colliroja, Astyanax fasciatus, is a new aquaculture species, and information on its dietary essential amino acid requirements is lacking. The whole body composition of 120 farmed fish (16.2 ± 8.8 g was determined to estimate the dietary essential amino acid requirement based on the ideal protein concept ((each essential amino acid/lysine x100, and the findings were correlated to the whole body essential amino acid content of Nile tilapia Oreochromis niloticus. The dietary essential amino acids, including cysteine and tyrosine, accounted for 5.46, 4.62, 1.16, 3.28, 5.63, 2.01, 2.59, 2.84, 4.66, 3.39, 0.65, and 3.51% of the total protein for lysine, arginine, histidine, isoleucine, leucine, methionine, methionine+tyrosine, phenylalanine, phenylalanine+tyrosine, threonine, tryptophan, and valine, respectively. There were positive linear and high correlations (r = 0.971 between the whole body amino acid profiles of colliroja and Nile tilapia. Thus, the whole body amino acid profile of colliroja might be used to estimate accurately the essential amino acid requirement.

  18. New insights on the origin of B chromosomes in Astyanax scabripinnis obtained by chromosome painting and FISH.

    Science.gov (United States)

    Vicari, Marcelo Ricardo; de Mello Pistune, Helena Flávia; Castro, Jonathan Pena; de Almeida, Mara Cristina; Bertollo, Luiz Antonio Carlos; Moreira-Filho, Orlando; Camacho, Juan Pedro M; Artoni, Roberto Ferreira

    2011-08-01

    Chromosome painting (CP) with a probe of B chromosome obtained by microdissection and fluorescence in situ hybridization (FISH) with probes of As51 satellite DNA, C( o )t-1 DNA, and 18S and 5S rDNA confirmed sharing of some repetitive DNA but not rDNA between A and B chromosomes in the fish Astyanax scabripinnis. Meiotic analysis revealed a pachytene B chromosome bivalent nearly half the size of its mitotic configuration, suggesting a self-pairing of B chromosome arms. Such an isochromosome nature of somatic B chromosome was further evidenced by CP and FISH. All the findings obtained suggest (i) intraspecific origin of B chromosome, and (ii) evolutionary enrichment of repetitive DNA classes, especially those contained in the C( o )t-1 and the As51 probes, in B chromosome. However, the precise origin of B chromosome in the present species remains to be elucidated by further molecular cytogenetic analysis because of painting of some A chromosome regions with the B chromosome-derived probe.

  19. The sensitivity of lateral line receptors and their role in the behavior of Mexican blind cavefish (Astyanax mexicanus).

    Science.gov (United States)

    Yoshizawa, Masato; Jeffery, William R; van Netten, Sietse M; McHenry, Matthew J

    2014-03-15

    The characid fish species Astyanax mexicanus offers a classic comparative model for the evolution of sensory systems. Populations of this species evolved in caves and became blind while others remained in streams (i.e. surface fish) and retained a functional visual system. The flow-sensitive lateral line receptors, called superficial neuromasts, are more numerous in cavefish than in surface fish, but it is unclear whether individual neuromasts differ in sensitivity between these populations. The aims of this study were to determine whether the neuromasts in cavefish impart enhanced sensitivity relative to surface fish and to test whether this aids their ability to sense flow in the absence of visual input. Sensitivity was assessed by modeling the mechanics and hydrodynamics of a flow stimulus. This model required that we measure the dimensions of the transparent cupula of a neuromast, which was visualized with fluorescent microspheres. We found that neuromasts within the eye orbit and in the suborbital region were larger and consequently about twice as sensitive in small adult cavefish as in surface fish. Behavioral experiments found that these cavefish, but not surface fish, were attracted to a 35 Hz flow stimulus. These results support the hypothesis that the large superficial neuromasts of small cavefish aid in flow sensing. We conclude that the morphology of the lateral line could have evolved in cavefish to permit foraging in a cave environment.

  20. A potential benefit of albinism in Astyanax cavefish: downregulation of the oca2 gene increases tyrosine and catecholamine levels as an alternative to melanin synthesis.

    Science.gov (United States)

    Bilandžija, Helena; Ma, Li; Parkhurst, Amy; Jeffery, William R

    2013-01-01

    Albinism, the loss of melanin pigmentation, has evolved in a diverse variety of cave animals but the responsible evolutionary mechanisms are unknown. In Astyanax mexicanus, which has a pigmented surface dwelling form (surface fish) and several albino cave-dwelling forms (cavefish), albinism is caused by loss of function mutations in the oca2 gene, which operates during the first step of the melanin synthesis pathway. In addition to albinism, cavefish have evolved differences in behavior, including feeding and sleep, which are under the control of the catecholamine system. The catecholamine and melanin synthesis pathways diverge after beginning with the same substrate, L-tyrosine. Here we describe a novel relationship between the catecholamine and melanin synthesis pathways in Astyanax. Our results show significant increases in L-tyrosine, dopamine, and norepinephrine in pre-feeding larvae and adult brains of Pachón cavefish relative to surface fish. In addition, norepinephrine is elevated in cavefish adult kidneys, which contain the teleost homologs of catecholamine synthesizing adrenal cells. We further show that the oca2 gene is expressed during surface fish development but is downregulated in cavefish embryos. A key finding is that knockdown of oca2 expression in surface fish embryos delays the development of pigmented melanophores and simultaneously increases L-tyrosine and dopamine. We conclude that a potential evolutionary benefit of albinism in Astyanax cavefish may be to provide surplus L-tyrosine as a precursor for the elevated catecholamine synthesis pathway, which could be important for adaptation to the challenging cave environment.

  1. A potential benefit of albinism in Astyanax cavefish: downregulation of the oca2 gene increases tyrosine and catecholamine levels as an alternative to melanin synthesis.

    Directory of Open Access Journals (Sweden)

    Helena Bilandžija

    Full Text Available Albinism, the loss of melanin pigmentation, has evolved in a diverse variety of cave animals but the responsible evolutionary mechanisms are unknown. In Astyanax mexicanus, which has a pigmented surface dwelling form (surface fish and several albino cave-dwelling forms (cavefish, albinism is caused by loss of function mutations in the oca2 gene, which operates during the first step of the melanin synthesis pathway. In addition to albinism, cavefish have evolved differences in behavior, including feeding and sleep, which are under the control of the catecholamine system. The catecholamine and melanin synthesis pathways diverge after beginning with the same substrate, L-tyrosine. Here we describe a novel relationship between the catecholamine and melanin synthesis pathways in Astyanax. Our results show significant increases in L-tyrosine, dopamine, and norepinephrine in pre-feeding larvae and adult brains of Pachón cavefish relative to surface fish. In addition, norepinephrine is elevated in cavefish adult kidneys, which contain the teleost homologs of catecholamine synthesizing adrenal cells. We further show that the oca2 gene is expressed during surface fish development but is downregulated in cavefish embryos. A key finding is that knockdown of oca2 expression in surface fish embryos delays the development of pigmented melanophores and simultaneously increases L-tyrosine and dopamine. We conclude that a potential evolutionary benefit of albinism in Astyanax cavefish may be to provide surplus L-tyrosine as a precursor for the elevated catecholamine synthesis pathway, which could be important for adaptation to the challenging cave environment.

  2. Efeitos do RoundupTM e do Thiodan® em adultos de Astyanax bimaculatus (Characidae: Teleostei): Valores de CL50 e morfologia testicular.

    OpenAIRE

    Silva Filho, Paulo Burlamaqui da

    2010-01-01

    O uso indiscriminado de agroquímicos na agricultura moderna está desencadeando prejuízos graves para o meio ambiente e que representam séria ameaça para a sobrevivência de ecossistemas importantes. Neste sentido, o objetivo do presente trabalho foi determinar a CL50-96h e avaliar a influência do herbicida Roundup™ (Monsanto) e do inseticida Thiodan® (Bayer) sobre a morfologia testicular do lambari Astyanax bimaculatus. Para isso, foram selecionados lotes homogêneos de lambaris machos, a...

  3. What is the genus?

    CERN Document Server

    Popescu-Pampu, Patrick

    2016-01-01

    Exploring several of the evolutionary branches of the mathematical notion of genus, this book traces the idea from its prehistory in problems of integration, through algebraic curves and their associated Riemann surfaces, into algebraic surfaces, and finally into higher dimensions. Its importance in analysis, algebraic geometry, number theory and topology is emphasized through many theorems. Almost every chapter is organized around excerpts from a research paper in which a new perspective was brought on the genus or on one of the objects to which this notion applies. The author was motivated by the belief that a subject may best be understood and communicated by studying its broad lines of development, feeling the way one arrives at the definitions of its fundamental notions, and appreciating the amount of effort spent in order to explore its phenomena.

  4. Genus Ranges of Chord Diagrams.

    Science.gov (United States)

    Burns, Jonathan; Jonoska, Nataša; Saito, Masahico

    2015-04-01

    A chord diagram consists of a circle, called the backbone, with line segments, called chords, whose endpoints are attached to distinct points on the circle. The genus of a chord diagram is the genus of the orientable surface obtained by thickening the backbone to an annulus and attaching bands to the inner boundary circle at the ends of each chord. Variations of this construction are considered here, where bands are possibly attached to the outer boundary circle of the annulus. The genus range of a chord diagram is the genus values over all such variations of surfaces thus obtained from a given chord diagram. Genus ranges of chord diagrams for a fixed number of chords are studied. Integer intervals that can be, and those that cannot be, realized as genus ranges are investigated. Computer calculations are presented, and play a key role in discovering and proving the properties of genus ranges.

  5. Desenvolvimento de juvenis de lambari Astyanax bimaculatus (Linnaeus, 1758, sob diferentes densidades de estocagem em tanques-rede Development of Astyanax bimaculatus (Linnaeus, 1758 juveniles at different stocking densities in net ponds

    Directory of Open Access Journals (Sweden)

    Carmino Hayashi

    2001-05-01

    Full Text Available O objetivo deste trabalho foi avaliar a influência da densidade de estocagem sobre o desenvolvimento de juvenis de lambari (Astyanax bimaculatus, em tanques-rede, em sua fase inicial. Foram utilizados 300 peixes, com peso vivo inicial médio com quatro tratamentos e seis repetições. Foram utilizadas as densidades de 31, 62, 93 e 124 peixes/m3 . Os parâmetros físico-químicos foram tomados a cada três dias. Observou-se efeito quadrático (p 3 proporciona indivíduos maiores; não obstante podem-se utilizar 124 peixes/m3 no cultivo de juvenis de lambari em tanques-rede, resultando em maior biomassa total, apesar de resultarem indivíduos menoresThe influence of stocking density on the development of juveniles at the initial phase in experimental net ponds is analyzed. Three hundred individuals with 0.50 to 0.02g mean initial live weight were distributed into a totally randomized design with four treatments and six repetitions. The density rates of 31, 62, 93 and 124 animals/m3 were used. The physical and chemical parameters were verified every three days. Although a quadratic effect (p 3 is the most efficient for their development. On the other hand, the rate of 124 individuals/m3 for the breeding of juveniles in net ponds is also practicable, though resulting in smaller individuals

  6. Genetic variability in Astyanax altiparanae Garutti & Britski, 2000 (Teleostei, Characidae from the Upper Paraná River basin, Brazil

    Directory of Open Access Journals (Sweden)

    Maria Dolores Peres

    2005-12-01

    Full Text Available Allozyme data was used to assess the genetic diversity Astyanax altiparanae populations from the floodplain of the Upper Paraná River (PR. Specimens were collected in the southern Brazilian state of Paraná from PR in Porto Rico municipality and Ribeirão Ficha (RF in Ubiratã municipality. The authors used 15% (w/v corn starch gel electrophoresis to identify 21 putative loci for 13 enzymatic systems: Aspartate aminotransferase, 2.6.1.1 (AAT, Acid phosphatase, 3.1.3.2 (ACP, Esterase, 3.1.1.1 (EST, Glycerol-3-phosphate dehydrogenase, 1.1.1.8 (G3PDH, Glucose-6-phosphate dehydrogenase, 1.1.1.49 (G6PDH, Glucose-6-phosphate isomerase, 5.3.1.9 (GPI, Iditol dehydrogenase, 1.1.1.14 (IDDH, Isocitrate dehydrogenase - NADP+, 1.1.1.42 (IDH, L-Lactate dehydrogenase, 1.1.1.27 (LDH, Malate dehydrogenase, 1.1.1.37 (MDH, Malate dehydrogenase - NADP+, 1.1.1.40 (MDHP, Phosphoglucomutase, 5.4.2.2 (PGM, and Superoxide dismutase, 1.15.1.1 (SOD. The proportion of polymorphic loci were estimated as 52.38% in the PR population and 38.10% in the RF population. Expected estimated heterozygosities were 0.1518 ± 0.0493 for the PR population and 0.0905 ± 0.0464 for the RF population. The A. altiparanae heterozygosity data were similar to previous estimates for other PR basin characid species. Allele frequencies were significantly different between the PR and RF populations in respect to some loci (Acp-1, G3pdh-1, Gpi-A, Iddh-1, Mdhp-1 and Mdhp-2. Wright’s statistics for all loci were estimated as Fis = 0.3919, Fit = 0.4804 and Fst = 0.1455. Our results show that the A. altiparanae populations studied are genetically different and have a high degree of genetic variability.

  7. Characterization and comparison of activity profiles exhibited by the cave and surface morphotypes of the blind Mexican tetra, Astyanax mexicanus.

    Science.gov (United States)

    Carlson, Brian M; Gross, Joshua B

    2017-08-17

    Departure from normal circadian rhythmicity and exposure to atypical lighting cues has been shown to adversely affect human health and wellness in a variety of ways. In contrast, adaptation to extreme environments has led many species to alter or even entirely abandon their reliance upon cyclic environmental inputs, principally daily cycles of light and darkness. The extreme darkness, stability and isolation of cave ecosystems has made cave-adapted species particularly attractive systems in which to study the consequences of life without light and the strategies that allow species to survive and even thrive in such environments. In order to further explore these questions, we have assessed the rhythmicity of locomotion in the blind Mexican tetra, Astyanax mexicanus, under controlled laboratory conditions. Using high-resolution video tracking assays, we characterized patterns in locomotor activity and spatial tank usage for members of the surface and Pachón cave populations. Here we demonstrate that cavefish have a higher overall level of activity and use the space within the trial tank differently than surface fish. Further, Pachón cavefish show circadian rhythmicity in both activity and spatial tank usage under a 12:12 light/dark cycle. We provide further evidence that these cavefish retain a weakly light-entrainable, endogenous circadian oscillator with limited capability to sustain rhythms in activity, but not spatial tank usage, in the absence of photic cues. Finally, we demonstrate a putative behavioral "masking effect" contributing to behavioral rhythms and provide evidence that exposure to constant darkness during development may alter behavioral patterns later in life. Copyright © 2017. Published by Elsevier Inc.

  8. Immunohistochemical, morphological and histometrical analyses of follicular development in Astyanax bimaculatus (Teleostei: Characidae) exposed to an organochlorine insecticide.

    Science.gov (United States)

    Marcon, Lucas; Thomé, Ralph Gruppi; Mounteer, Ann Honor; Bazzoli, Nilo; Rizzo, Elizete; Benjamin, Laércio Dos Anjos

    2017-09-01

    Thiodan(®) is an organochlorine insecticide used in agriculture that can reach aquatic ecosystems where it can affect fish reproduction. This research aimed to evaluate follicular development and the expression of integrin β1, collagen type IV and caspase 3 by morphological, histometrical and immunohistochemical analyses of Astyanax bimaculatus exposed to Thiodan(®). Treatments included three sublethal concentrations of Thiodan(®) (1.15, 2.30, and 5.60μgL(-1)) for 96h and a control without the insecticide. Mature females with ovaries in advanced follicular development were chosen for study (average weight: 11.52 ± 2.0g; average total length: 9.12 ± 0.64cm). The follicles of A. bimaculatus exhibited normal morphology, while the diameters of secondary follicles showed an increase (P< 0.05) in all concentrations when compared to the control group; a characteristic of follicles undergoing the initial stages of intoxication. Immunohistochemical analysis revealed secondary follicles with greater expression of integrin β1 and collagen type IV in cytoplasm of follicular cells than in the primary follicles in all treatments and in the control. Immunolocalization of caspase 3 was detected in follicular cells during secondary development in all tested concentrations of Thiodan(®) and the control. These analyses demonstrate positive immunolocalization throughout the course of follicular development, even in fish exposed to varying concentrations of Thiodan(®) for 96h, demonstrating that follicular cells retain their physiological integrity. Copyright © 2017 Elsevier Inc. All rights reserved.

  9. Role of the fish astyanax aeneus (Characidae) as a keystone nutrient recycler in low-nutrient neotropical streams

    Science.gov (United States)

    Small, G.E.; Pringle, C.M.; Pyron, M.; Duff, J.H.

    2011-01-01

    Nutrient recycling by animals is a potentially important biogeochemical process in both terrestrial and aquatic ecosystems. Stoichiometric traits of individual species may result in some taxa playing disproportionately important roles in the recycling of nutrients relative to their biomass, acting as keystone nutrient recyclers. We examined factors controlling the relative contribution of 12 Neotropical fish species to nutrient recycling in four streams spanning a range of phosphorus (P) levels. In high-P conditions (135 ??g/L soluble reactive phosphorus, SRP), most species fed on P-enriched diets and P excretion rates were high across species. In low-P conditions (3 ??g/L SRP), aquatic food resources were depleted in P, and species with higher body P content showed low rates of P recycling. However, fishes that were subsidized by terrestrial inputs were decoupled from aquatic P availability and therefore excreted P at disproportionately high rates. One of these species, Astyanax aeneus (Characidae), represented 12% of the total population and 18% of the total biomass of the fish assemblage in our focal low-P study stream but had P excretion rates >10-fold higher than other abundant fishes. As a result, we estimated that P excretion by A. aeneus accounted for 90% of the P recycled by this fish assemblage and also supplied ???90% of the stream P demand in this P-limited ecosystem. Nitrogen excretion rates showed little variation among species, and the contribution of a given species to ecosystem N recycling was largely dependent upon the total biomass of that species. Because of the high variability in P excretion rates among fish species, ecosystem-level P recycling could be particularly sensitive to changes in fish community structure in P-limited systems. ?? 2011 by the Ecological Society of America.

  10. DNA sequences of troglobitic nicoletiid insects support Sierra de El Abra and the Sierra de Guatemala as a single biogeographical area: Implications for Astyanax

    Directory of Open Access Journals (Sweden)

    Luis Espinasa

    2014-03-01

    Full Text Available The blind Mexican tetra fish, Astyanax mexicanus, has become the most influential model for research of cave adapted organisms. Many authors assume that the Sierra de Guatemala populations and the Sierra de El Abra populations are derived from two independent colonizations. This assumption arises in part from biogeography. The 100 m high, 100 m wide Servilleta Canyon of the Boquillas River separates both mountain ranges and is an apparent barrier for troglobite dispersion. Anelpistina quinterensis (Nicoletiidae, Zygentoma, Insecta is one of the most troglomorphic nicoletiid silverfish insects ever described. 16S rRNA sequences support that this species migrated underground to reach both mountain ranges within less than 12,000 years. Furthermore, literature shows a plethora of aquatic and terrestrial cave restricted species that inhabit both mountain ranges. Thus, the Servilleta canyon has not been an effective biological barrier that prevented underground migration of troglobites between the Sierra de Guatemala and the Sierra de El Abra. The Boquillas River has changed its course throughout time. Caves that in the past connected the two Sierras were only recently geologically truncated by the erosion of the new river course. It is likely that, with the geological changes of the area and throughout the 2-8 million years of evolutionary history of cave Astyanax, there have been opportunities to migrate across the Servilleta canyon.

  11. The occurence of black spot disease in Astyanax aff. fasciatus(characiformes: characidae in the Guaíba Lake basin, RS, Brazil

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    F Flores-Lopes

    Full Text Available Black spot disease is common in freshwater fish and is usually caused by the metacercaria stage of digenetic trematodes, normally from the Diplostomidae family. The present study evaluated the prevalence and intensity of this disease in Astyanax aff. fasciatus(Teleostei: Characiformes in the Guaíba Lake basin (RS, Brazil, including body parts assessment and the points of sampling with higher occurrence of black spots. Fish samples were taken seasonally from December 2002 until October 2004. The samples were collected with the use of a seine net at eleven points. The specimens were fixed in 10% formalin and stored in 70% ethanol. Black spot disease showed a low frequency in the Guaíba lake basin (2.07% and no specificity to the species Astyanax aff. fasciatus was observed. A high prevalence among the individuals and high intensity of infection levels was found in the ventral and dorsal regions in relation to other body parts (e.g., pectoral, pelvic and anal regions. Among the sampling points studied, we observed a higher prevalence on samples collected at points Gasômetro, Saco da Alemoa and Sinos, located in open areas with less occurrence of mollusks.

  12. The occurence of black spot disease in Astyanax aff. fasciatus (Characiformes: Characidae) in the Guaíba Lake basin, RS, Brazil.

    Science.gov (United States)

    Flores-Lopes, F

    2014-08-01

    Black spot disease is common in freshwater fish and is usually caused by the metacercaria stage of digenetic trematodes, normally from the Diplostomidae family. The present study evaluated the prevalence and intensity of this disease in Astyanax aff. fasciatus (Teleostei: Characiformes) in the Guaíba Lake basin (RS, Brazil), including body parts assessment and the points of sampling with higher occurrence of black spots. Fish samples were taken seasonally from December 2002 until October 2004. The samples were collected with the use of a seine net at eleven points. The specimens were fixed in 10% formalin and stored in 70% ethanol. Black spot disease showed a low frequency in the Guaíba lake basin (2.07%) and no specificity to the species Astyanax aff. fasciatus was observed. A high prevalence among the individuals and high intensity of infection levels was found in the ventral and dorsal regions in relation to other body parts (e.g., pectoral, pelvic and anal regions). Among the sampling points studied, we observed a higher prevalence on samples collected at points Gasômetro, Saco da Alemoa and Sinos, located in open areas with less occurrence of mollusks.

  13. Adición a los registros de tapir centroamericano (Tapirus bairdii en Oaxaca, México Addition to the records of Baird's Tapir (Tapirus bairdii in Oaxaca, Mexico

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    Christian Alejandro Delfín-Alfonso

    2008-12-01

    Full Text Available En el mes de febrero de 2007, en el municipio de Santo Domingo Ingenio, distrito de Juchitán, Oaxaca, obtuvimos el registro de un ejemplar de tapir centroamericano (Tapirus bairdii mediante una fotografía proporcionada por los habitantes del sitio. La foto que fue tomada en el 2005, durante la época de lluvias, muestra un tapir adulto cazado a 1.5 km al norte de Santo Domingo. Es el registro más reciente de tapir en Oaxaca y sugiere que éste probablemente se desplazó de la zona montañosa de Los Chimalapas hacia el istmo de Tehuantepec.In February 2007, in the municipality of Santo Domingo Ingenio, Juchián District, Oaxaca state, we obtained the record of an individual of Baird's Tapir (Tapirus bairdii from a photograph provided by the inhabitants of the site. The photograph was taken in 2005 during the rainy season, showing a dead adult tapir which was hunted at only 1.5 km north from Santo Domingo town. This is the most recent record of Baird-Tapir in the state of Oaxaca and suggests that this individual probably moved from the mountainous zone of Los Chimalapas towards the Itsmus of Tehuantepec.

  14. Ocorrência e ecologia trófica de quatro espécies de Astyanax (Characidae em diferentes rios da bacia do rio Tibagi, Paraná, Brasil Occurrence and trophic ecology of four species of Astyanax (Characidae in different rivers of the Tibagi River Basin, Paraná, Brazil

    Directory of Open Access Journals (Sweden)

    Sirlei Terezinha Bennemann

    2005-09-01

    Full Text Available Na bacia do rio Tibagi, trechos dos rios Fortaleza, Iapó e Tibagi foram amostrados mensalmente, de maio de 2001 a abril de 2002, com tarrafas e redes de espera de diferentes malhagens. Foram capturados indivíduos de quatro espécies de Astyanax. Para conhecer como essas espécies utilizam o hábitat desses rios, foi calculada a constância, e as freqüências em número de exemplares foram comparadas pela análise de similaridade Bray-Curtis. A composição percentual dos alimentos consumidos foi ordenada usando-se a Análise de Componentes Principais (ACP. As proporções dos recursos alimentares foram avaliadas e classificadas quanto à natureza (animal ou material vegetal e origem (alóctone e autóctone. A constância e a baixa similaridade na abundância revelaram que as espécies têm preferências quanto ao porte do rio ou por determinado hábitat. Astyanax altiparanae Garutti & Britski, 2000 e A. fasciatus (Cuvier, 1819 ocorreram nos de maior porte, mas foram constantes somente no rio Tibagi. Astyanax eigenmanniorum (Cope, 1894 ocorreu em todos os rios, mas prefere hábitats próximos às desembocaduras de afluentes de grandes rios. Astyanax scabripinnis (Jenyns, 1842 esteve restrita ao Fortaleza, o rio de menor porte, subafluente do rio Tibagi. O número de itens alimentares consumidos variou de 11 a 23. Entre os alimentos principais, três itens foram comuns para as quatro espécies: restos de plantas (folhas e sementes de plantas terrestres, restos de insetos (de diferentes origens e não identificados e plantas aquáticas. Os vegetais e os insetos foram os principais alimentos para todas as espécies. A maior distinção na composição da dieta foi constatada para A. eigenmaniorum, devido à sua habilidade em explorar as plantas aquáticas, presentes em abundância, consumidas junto com carvão/sedimento, que estavam nas margens rochosas do rio Iapó. A similaridade quanto à origem e ao tipo de alimento consumido pelas quatro esp

  15. Biodiversity of the genus Cladophialophora

    NARCIS (Netherlands)

    Badali, H.; Gueidan, C.; Najafzadeh, M.J.; Bonifaz, A.; Gerrits van den Ende, A.H.G.; de Hoog, G.S.

    2008-01-01

    Cladophialophora is a genus of black yeast-like fungi comprising a number of clinically highly significant species in addition to environmental taxa. The genus has previously been characterized by branched chains of ellipsoidal to fusiform conidia. However, this character was shown to have evolved s

  16. Biodiversity of the genus Cladophialophora

    NARCIS (Netherlands)

    Badali, H.; Gueidan, C.; Najafzadeh, M.J.; Bonifaz, A.; Gerrits van den Ende, A.H.G.; de Hoog, G.S.

    2008-01-01

    Cladophialophora is a genus of black yeast-like fungi comprising a number of clinically highly significant species in addition to environmental taxa. The genus has previously been characterized by branched chains of ellipsoidal to fusiform conidia. However, this character was shown to have evolved s

  17. Genus Distributions of Moebius Ladders

    Institute of Scientific and Technical Information of China (English)

    李德明

    2005-01-01

    The genus distribution of a graph is a polynomial whose coefficients are the partition of the number of embeddings with respect to the genera. In this paper,the genus distribution of Moebius ladders is provided which is an infinite class of 3-connected simple graphs.

  18. Spot the difference: Two cryptic species of Gyrodactylus von Nordmann, 1832 (Platyhelminthes: Monogenea) infecting Astyanax aeneus (Actinopterygii, Characidae) in Mexico.

    Science.gov (United States)

    Razo-Mendivil, Ulises; García-Vásquez, Adriana; Rubio-Godoy, Miguel

    2016-10-01

    Over the course of one year, undescribed specimens of Gyrodactylus were recovered from banded tetra, Astyanax aeneus collected in the La Antigua and Nautla river basins in central Veracruz, Mexico. Parasites were processed for morphometric and molecular analyses. Morphometrically, Gyrodactylus samples collected in the La Antigua river had slightly smaller haptoral structures than those collected from the Nautla river. During the 12month-collection of samples, however, water temperature varied considerably (ca. 20°C to 30°C), and this abiotic factor is known to affect the size of gyrodactylid attachment structures. Moreover, no clear discrimination was possible between individual parasites collected from the two rivers based on the morphology of the marginal hook, which is recognised as a very informative character to discriminate between species. The morphology of the ventral bar, however, differed between specimens from both rivers: worms from Nautla all had long, rounded processes on the ventral bar, which formed a relatively closed angle with the dorsal edge of the bar proper, while most - but not all - specimens from La Antigua had comparatively slender processes forming a more open angle with respect to the ventral bar. Phylogenetic analyses based on the sequences of the ITS1, 5.8S rRNA gene, and ITS2 of gyrodactylids indicated the existence of two distinct, well-supported lineages whose sequences differ by >4%, one of which was only found in the Nautla basin, while the other was collected in both river systems. A posteriori, principal component analysis (PCA) of the morphometric data of sequenced specimens indicated that features of the dorsal bar, the hamuli and the ventral bar enable discrimination between the two phylogenetic lineages. Based on these independent sources of information (morphometric and molecular data), two new species of Gyrodactylus are described: Gyrodactyluspakan n. sp. and Gyrodactylusteken n. sp. The phylogenetic relationships of

  19. Mapping of the 18S and 5S ribosomal RNA genes in Astyanax altiparanae Garutti & Britski, 2000 (Teleostei, Characidae from the upper Paraná river basin, Brazil

    Directory of Open Access Journals (Sweden)

    Carlos Alexandre Fernandes

    2006-01-01

    Full Text Available Fluorescence in situ hybridization (FISH was undertaken in order to determinate the chromosomal distribution pattern of 18S and 5S ribosomal DNAs (rDNA in four populations of the characid fish Astyanax altiparanae from the upper Paraná river basin, Brazil. The 18S rDNA probe FISH revealed numerical and positional variations among specimens from the Keçaba stream compared to specimens of the other populations studied. In contrast to the variable 18S rDNA distribution pattern, highly stable chromosomal positioning of the 5S rDNA sites was observed in the four A. altiparanae populations. Divergence in the distribution pattern of 18S and 5S rDNA sites is also discussed.

  20. Fourier transform-infrared photoacoustic spectroscopy applied in fish scales to access environmental integrity: A case study of Astyanax altiparanae species

    Science.gov (United States)

    Santana, C. A.; Andrade, L. H. C.; Súarez, Y. R.; Yukimitu, K.; Moraes, J. C. S.; Lima, S. M.

    2015-09-01

    Fish scales have been used to differentiate fish species and to give information on water pollution, besides others different purposes. In the present work, we are proposing, for the first time to our knowledge, to available the absorption from fish scales with Fourier Transform Infrared Photoacoustic Spectroscopy (FTIR-PAS) to assess the environmental integrity of different habitats. The infrared absorption measurements were performed directly on fish scales from the Astyanax altiparanae species, in order to check if the scales, and consequently the species, can be used as environmental bioindicator. The main absorption intensities were used as variables in the multivariate statistical analysis. It was noted that the chemical composition of the scales is directly related to the available food in the habitats, which is related to the integrity level of the environmental. The results point the fish scales as bioindicator to be applied with FTIR-PAS for monitoring aquatic ecosystems.

  1. Albinism in phylogenetically and geographically distinct populations of Astyanax cavefish arises through the same loss-of-function Oca2 allele.

    Science.gov (United States)

    Gross, J B; Wilkens, H

    2013-08-01

    The Mexican tetra, Astyanax mexicanus, comprises 29 populations of cave-adapted fish distributed across a vast karst region in northeastern Mexico. These populations have a complex evolutionary history, having descended from 'old' and 'young' ancestral surface-dwelling stocks that invaded the region ∼6.7 and ∼2.8 MYa, respectively. This study investigates a set of captive, pigmented Astyanax cavefish collected from the Micos cave locality in 1970, in which albinism appeared over the past two decades. We combined novel coloration analyses, coding sequence comparisons and mRNA expression level studies to investigate the origin of albinism in captive-bred Micos cavefish. We discovered that albino Micos cavefish harbor two copies of a loss-of-function ocular and cutaneous albinism type II (Oca2) allele previously identified in the geographically distant Pachón cave population. This result suggests that phylogenetically young Micos cavefish and phylogenetically old Pachón cave fish inherited this Oca2 allele from the ancestral surface-dwelling taxon. This likely resulted from the presence of the loss-of-function Oca2 haplotype in the 'young' ancestral surface-dwelling stock that colonized the Micos cave and also introgressed into the ancient Pachón cave population. The appearance of albinism in captive Micos cavefish, caused by the same loss-of-function allele present in Pachón cavefish, implies that geographically and phylogenetically distinct cave populations can evolve the same troglomorphic phenotype from standing genetic variation present in the ancestral taxon.

  2. Composite Genus One Belyi Maps

    CERN Document Server

    Vidunas, Raimundas

    2016-01-01

    Motivated by a demand for explicit genus 1 Belyi maps from physics, we give an efficient method of explicitly computing genus one Belyi maps by (1) composing covering maps from elliptic curves to the Riemann surface with the simpler, univariate, genus zero Belyi maps as well as by (2) composing further with isogenies of the elliptic curve. This gives many new explicit dessins on the doubly periodic plane, including several which have been realized in the physics literature as so-called brane-tilings in the context of quiver gauge theories.

  3. Chemodiversity in the genus Aspergillus

    DEFF Research Database (Denmark)

    Frisvad, Jens Christian; Larsen, Thomas Ostenfeld

    2015-01-01

    to be characterized. The genus Aspergillus is cladistically holophyletic but phenotypically polythetic and very diverse and is associated to quite different sexual states. Following the one fungus one name system, the genus Aspergillus is restricted to a holophyletic clade that include the morphologically different...... biosynthetic family isoextrolites. However, it appears that secondary metabolites from one Aspergillus section have analogous metabolites in other sections (here also called heteroisoextrolites). In this review, we give a genus-wide overview of secondary metabolite production in Aspergillus species. Extrolites...

  4. Condition factor of Astyanax intermedius Eigenmann, 1908 (OSTEICHTHYES, CHARACIDAE parasitised by Paracymothoa astyanaxi Lemos de Castro, 1955 (CRUSTACEA, CYMOTHOIDAE in the Grande River, Serra do Mar State Park - Santa Virgínia Unit, São Paulo, Brazil

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    LM Gomiero

    Full Text Available In this work the length-weight relationship and the condition factor of Astyanax intermedius parasitised and not by Paracymothoa astyanaxi were analysed in the Grande River. The length-weight relationship was estimated for females, males and immatures, and seasonally for the fishes and the parasites through the expression W = aLb. The condition factor of non-parasitised specimens differed seasonally and between sexes, contrasting with the results for parasitised fishes which showed no differences between sexes and season. The condition factor of non-parasitised specimens was higher than that of the parasitised fishes. Specimens of Astyanax intermedius parasitised do not have the same biotic conditions compared to non-parasitised individuals, in which the condition factor was similar over the years. In conclusion, parasitism by P. astyanaxi has deleterious effects on this host population which may cause changes in the reproductive and food dynamics of parasitised specimens due to low body conditions.

  5. Condition factor of Astyanax intermedius Eigenmann, 1908 (OSTEICHTHYES, CHARACIDAE) parasitised by Paracymothoa astyanaxi Lemos de Castro, 1955 (CRUSTACEA, CYMOTHOIDAE) in the Grande River, Serra do Mar State Park - Santa Virgínia Unit, São Paulo, Brazil.

    Science.gov (United States)

    Gomiero, L M; Souza, U P; Braga, F M S

    2012-05-01

    In this work the length-weight relationship and the condition factor of Astyanax intermedius parasitised and not by Paracymothoa astyanaxi were analysed in the Grande River. The length-weight relationship was estimated for females, males and immatures, and seasonally for the fishes and the parasites through the expression W = aLb. The condition factor of non-parasitised specimens differed seasonally and between sexes, contrasting with the results for parasitised fishes which showed no differences between sexes and season. The condition factor of non-parasitised specimens was higher than that of the parasitised fishes. Specimens of Astyanax intermedius parasitised do not have the same biotic conditions compared to non-parasitised individuals, in which the condition factor was similar over the years. In conclusion, parasitism by P. astyanaxi has deleterious effects on this host population which may cause changes in the reproductive and food dynamics of parasitised specimens due to low body conditions.

  6. The genus Vitex: A review

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    Anita Rani

    2013-01-01

    Full Text Available The review includes 161 references on the genus Vitex, and comprises ethnopharmacology, morphology and microscopy, phytoconstituents, pharmacological reports, clinical studies, and toxicology of the prominent species of Vitex. Essential oils, flavonoids, iridoid glycosides, diterpenoides and ligans constitute major classes of phytoconstituents of the genus. A few species of this genus have medicinal value, among these, leaves and fruits of V. agnus-castus Linn. (Verbenaceae has been traditionally used in treatment of women complaints. V. agnus-castus has also been included in herbal remedies, which are in clinical use to regulate the menstrual cycle, reduce premenstrual symptom tension and anxiety, treat some menopausal symptoms as well as to treat hormonally induced acne. Despite a long tradition of use of some species, the genus has not been explored properly. In the concluding part, the future scope of Vitex species has been emphasized with a view to establish their multifarious biological activities and mode of action.

  7. The genus Cladosporium.

    Science.gov (United States)

    Bensch, K; Braun, U; Groenewald, J Z; Crous, P W

    2012-06-15

    A monographic revision of the hyphomycete genus Cladosporium s. lat. (Cladosporiaceae, Capnodiales) is presented. It includes a detailed historic overview of Cladosporium and allied genera, with notes on their phylogeny, systematics and ecology. True species of Cladosporium s. str. (anamorphs of Davidiella), are characterised by having coronate conidiogenous loci and conidial hila, i.e., with a convex central dome surrounded by a raised periclinal rim. Recognised species are treated and illustrated with line drawings and photomicrographs (light as well as scanning electron microscopy). Species known from culture are described in vivo as well as in vitro on standardised media and under controlled conditions. Details on host range/substrates and the geographic distribution are given based on published accounts, and a re-examination of numerous herbarium specimens. Various keys are provided to support the identification of Cladosporium species in vivo and in vitro. Morphological datasets are supplemented by DNA barcodes (nuclear ribosomal RNA gene operon, including the internal transcribed spacer regions ITS1 and ITS2, the 5.8S nrDNA, as well as partial actin and translation elongation factor 1-α gene sequences) diagnostic for individual species. In total 993 names assigned to Cladosporium s. lat., including Heterosporium (854 in Cladosporium and 139 in Heterosporium), are treated, of which 169 are recognized in Cladosporium s. str. The other taxa are doubtful, insufficiently known or have been excluded from Cladosporium in its current circumscription and re-allocated to other genera by the authors of this monograph or previous authors. Cladosporium allicinum (Fr.: Fr.) Bensch, U. Braun & Crous, comb. nov., C. astroideum var. catalinense U. Braun, var. nov., Fusicladium tectonicola (Yong H. He & Z.Y. Zhang) U. Braun & Bensch, comb. nov., Septoidium uleanum (Henn.) U. Braun, comb. nov., Zasmidium adeniae (Hansf.) U. Braun, comb. nov., Zasmidium dianellae (Sawada

  8. The genus Cladosporium

    Science.gov (United States)

    Bensch, K.; Braun, U.; Groenewald, J.Z.; Crous, P.W.

    2012-01-01

    A monographic revision of the hyphomycete genus Cladosporium s. lat. (Cladosporiaceae, Capnodiales) is presented. It includes a detailed historic overview of Cladosporium and allied genera, with notes on their phylogeny, systematics and ecology. True species of Cladosporium s. str. (anamorphs of Davidiella), are characterised by having coronate conidiogenous loci and conidial hila, i.e., with a convex central dome surrounded by a raised periclinal rim. Recognised species are treated and illustrated with line drawings and photomicrographs (light as well as scanning electron microscopy). Species known from culture are described in vivo as well as in vitro on standardised media and under controlled conditions. Details on host range/substrates and the geographic distribution are given based on published accounts, and a re-examination of numerous herbarium specimens. Various keys are provided to support the identification of Cladosporium species in vivo and in vitro. Morphological datasets are supplemented by DNA barcodes (nuclear ribosomal RNA gene operon, including the internal transcribed spacer regions ITS1 and ITS2, the 5.8S nrDNA, as well as partial actin and translation elongation factor 1-α gene sequences) diagnostic for individual species. In total 993 names assigned to Cladosporium s. lat., including Heterosporium (854 in Cladosporium and 139 in Heterosporium), are treated, of which 169 are recognized in Cladosporium s. str. The other taxa are doubtful, insufficiently known or have been excluded from Cladosporium in its current circumscription and re-allocated to other genera by the authors of this monograph or previous authors. Taxonomic novelties: Cladosporium allicinum (Fr.: Fr.) Bensch, U. Braun & Crous, comb. nov., C. astroideum var. catalinense U. Braun, var. nov., Fusicladium tectonicola (Yong H. He & Z.Y. Zhang) U. Braun & Bensch, comb. nov., Septoidium uleanum (Henn.) U. Braun, comb. nov., Zasmidium adeniae (Hansf.) U. Braun, comb. nov., Zasmidium

  9. Revision of the genus Phaeanthus (Annonaceae)

    NARCIS (Netherlands)

    Mols, J.B.; Keßler, P.J.A.

    2000-01-01

    A revision of the genus Phaeanthus Hook.f. & Thomson (Annonaceae) is presented. The genus comprises 8 species. A key to the fruiting and/or flowering specimens of the genus is included. The genus consists of shrubs to small-sized trees from Malesia and Vietnam. It is characterised by sepals and

  10. The genus Cyclidiopsis: an obituary.

    Science.gov (United States)

    Bennett, Matthew S; Triemer, Richard E

    2014-01-01

    Since its creation in 1917 the genus Cyclidiopsis, and its validity, has been a source of debate among euglenid taxonomists. While many authors have supported its legitimacy, various other authors have considered it to be a subgenus of Astasia or even promoted its complete dissolution. In this study, we have sequenced the small subunit and large subunit ribosomal DNA of Cyclidiopsis acus, the type species for the genus. Subsequent phylogenetic analyses showed that C. acus grouped with taxa from the genus Lepocinclis, which necessitated the removal of this taxon from Cyclidiopsis and into Lepocinclis as Lepocinclis cyclidiopsis nom. nov. After an extensive literature search it was determined that only two other previously described Cyclidiopsis taxa were morphologically distinct, and the rest were reassigned as synonyms of L. cyclidiopsis. These findings prompted a re-examination of the initial description of Cyclidiopsis, and it was determined that the morphological characters establishing the genus as a distinct group were no longer valid in light of current phylogenetic analyses and the emended generic description for Lepocinclis. Therefore, the remaining two taxa were formally moved to the genus Lepocinclis as L. crescentia comb. nov. and L. pseudomermis comb. nov.

  11. THE GENUS CULLENIA Wight * (Bombacaceae

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    A. J. G. H. KOSTERMANS

    1956-12-01

    Full Text Available The monotypic genus Cullenia was established by Wight (IconesPI. Ind. or. 5 (1 : pi. 1761—62 & text, 1851, who differentiated it fromDurio Adans. mainly by the lack of a corolla and the position and shapeof the anthers. The only species, originally described as Durio ceylanicusby Gardner, was cited by Wight as Cullenia excelsa Wight. K. Schumanncorrected the specific epithet rather casually and atributed it (wronglyto Wight. Bentham (in Benth. & Hook., Gen. pi. 1: 212. 1867; Baillon(Hist. pi. 4: 159. 1872, Masters (in Hook, f., Fl. Br. Ind. 1: 350. 1874and Beccari (Malesia 3: 219. 1889 accepted the genus.Bakhuizen van den Brink (in Bull. Jard. bot. Buitenzorg III, 6: 228.1924 incorporated the genus in Durio.In my opinion Cullenia represents a "good" genus by its lack ofcorolla. Alston, although accepting Bakhuizen's reduction, informed mepersonally, that he, too, is inclined to consider Cullenia different fromDurio.The pollen were described as being naked and pedicellate by Gardner;this wrong statement was corrected by Wight; the anthers are pedicellateand one-celled.In this paper a new Cullenia species is described, which strengthensthe position of the genus; both species are restricted to the rain forestregion of Ceylon and the Southern Indian Peninsula.

  12. Performance and bromatologic analysis of red tail lambari Astyanax sp F (Pisces: characidae submitted to the smoking process / Rendimento e análise bromatológica do lambari do rabo vermelho Astyanax sp F (Pisces: characidae submetido ao processo de defumação

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    Carlos Eduardo Weirich

    2009-12-01

    Full Text Available The aim of this study was to evaluate the time of hot smoked and the influence of carcass quality of the red tail lambari Astyanax sp F. Sixty lambaris, eviscerated with head, skin, bones, spinal column, fins, however, without scale. With a medium weight and length of 22.22±4.32g and 11.32±00.63cm were utilized. The animals were submitted to humid salted (25% of sodium chloride for 45 minutes and condiments, been later hot smoked for a period of 90, 180, 270, 360 min. After the smoking process, the fish were weighted and later the humidity tenor, gross protein, lipids and mineral matter of the carcass of the animals were calculated. The results showed differences (P O objetivo do presente trabalho foi avaliar o tempo de defumação a quente e a influência sobre a qualidade de carcaça de lambaris Astyanax sp. F. Foram utilizados 60 lambaris, com peso e comprimento médio de 22,22±4,32g e 11,32±0,63cm, eviscerados e com cabeça, pele, espinhas, coluna vertebral, nadadeiras, porém, sem escamas. Os animais foram submetidos à salga úmida (25% de cloreto de sódio por 45 minutos e condimentos, sendo posteriormente defumados a quente, por um período de 90, 180, 270 e 360min. Após o processo de defumação, os peixes foram pesados e posteriormente calculados os teores de umidade, proteína bruta, lipídeos e matéria mineral da carcaça dos animais. Os resultados mostraram diferenças (P 0,05 entre os diferentes tempos de defumação. Portanto, conclui-se que para o Astyanax sp F o tempo de defumação de 225min7seg é o período de defumação indicado para o melhor produto final.

  13. On genus expansion of superpolynomials

    CERN Document Server

    Mironov, A; Sleptsov, A; Smirnov, A

    2013-01-01

    Recently it was shown that the (Ooguri-Vafa) generating function of HOMFLY polynomials is the Hurwitz partition function, i.e. that the dependence of the HOMFLY polynomials on representation is naturally captured by symmetric group characters (cut-and-join eigenvalues). The genus expansion and expansion through Vassiliev invariants explicitly demonstrate this phenomenon. In the present letter we claim that the superpolynomials are not functions of such a type: symmetric group characters do not provide an adequate linear basis for their expansions. Deformation to superpolynomials is, however, straightforward in the multiplicative basis:the Casimir operators are beta-deformed to Hamiltonians of the Calogero-Moser-Sutherland system. Applying this trick to the genus and Vassiliev expansions, we observe that the deformation is rather straightforward only for the thin knots. Beyond this family additional algebraically independent terms appear in the Vassiliev and genus expansions. This can suggest that the superpol...

  14. Strong embeddings of minimum genus

    CERN Document Server

    Mohar, Bojan

    2009-01-01

    A "folklore conjecture, probably due to Tutte" (as described in [P.D. Seymour, Sums of circuits, Graph theory and related topics (Proc. Conf., Univ. Waterloo, 1977), pp. 341-355, Academic Press, 1979]) asserts that every bridgeless cubic graph can be embedded on a surface of its own genus in such a way that the face boundaries are cycles of the graph. In this paper we consider closed 2-cell embeddings of graphs and show that certain (cubic) graphs (of any fixed genus) have closed 2-cell embedding only in surfaces whose genus is very large (proportional to the order of these graphs), thus providing plethora of strong counterexamples to the above conjecture. The main result yielding such counterexamples may be of independent interest.

  15. The medicinal chemistry of genus Aralia.

    Science.gov (United States)

    Clement, Jason A; Clement, Ella S H

    2015-01-01

    The genus Aralia contains many plants used medicinally in Asia and the Americas. Although many members of this genus are used medicinally, the vast majority of this genus has not been explored chemically. The species of Aralia that have been explored chemically have yielded compounds of several classes, including triterpenoid saponins, sterols, diterpenoids, and acetylenic lipids. Many of the biologically active components found in genus Aralia have been evaluated for their potential as lead compounds for drug discovery. This review will explore the medicinal chemistry of compounds reported from genus Aralia, and future prospects for this genus will be considered.

  16. Population structure, condition factor and reproductive period of Astyanax paranae (Eigenmann, 1914 (Osteichthyes: Characidae in a small and old Brazilian Reservoir

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    Milza Celi Fedatto Abelha

    2008-06-01

    Full Text Available The population structure, condition and reproductive period of Astyanax paranae adult individuals inhabiting a small reservoir were investigated. The fishes were quarterly captured from the riverine and lacustrine zones of the Alagados Reservoir, Paraná, Brazil, during 1996/1997 and 1998/1999. The sex ratio differed from 1:1 with the predominance of the females in all standard length classes and total population sample. The females showed higher condition than the males. Both the sexes presented lower mean condition values in April and higher mean condition values in July. The estimated values of the regression coefficient indicated isometric growth for the females and males. The gonadosomatic relationship reached a maximum value of 14.80% for the females and 8.43% for the males. The reproductive period possibly occurred from October to April.Foram investigados a estrutura populacional, condição e período reprodutivo de indivíduos adultos de Astyanax paranae habitantes de um pequeno reservatório. Os peixes foram capturados trimestralmente nas zonas fluvial e lacustre do reservatório de Alagados, Paraná, Brasil, durante 1996/1997 e 1998/1999. A proporção sexual diferiu de 1:1, com predomínio de fêmeas em todas as classes de tamanho padrão e na amostragem total da população. As fêmeas apresentaram melhor condição que os machos. Menores valores médios de condição ocorreram em abril e os maiores em julho, tanto para fêmeas quanto para machos. Os valores estimados do coeficiente de regressão linear indicaram crescimento isométrico para ambos os sexos. A relação gonadossomática alcançou o valor máximo de 14,80% para fêmeas e 8,43% para machos. O período reprodutivo da espécie possivelmente, se estendeu de outubro a abril.

  17. THE GENUS BURRETIODENDRON* Rehder (Tiliaceae

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    AJGH Kostermans

    2014-01-01

    Full Text Available Seven species of Burretwdendron are recognized, of which B. siamensis and B. yunnanensis are new to science. The distributional area of the genus covers Siam (one species, Yunnan (two species, Kweichow (one species;  Kwangsi (three species  and Tonkin (two species. B. tonkinensis is reduced to the synonymy of B. hsienmu. A key to the species is presented.

  18. Additions to the genus Acoridium

    NARCIS (Netherlands)

    Ames, Oakes

    1937-01-01

    The genus Acoridium is characterized by an extraordinary history. The original species, A. tenellum, a native of the Philippine Islands, was described at length from a fruiting specimen in 1843 by Nees von Esenbeck and referred to the Philydraceae. This treatment was prompted by the aspect of the pl

  19. Determination of growth curve throwgh scales lecture in different body regions of Astyanax bimaculatus (Linnaeus, 1758 (Pisces, Characidae, in Ibitinga reservoir, São Paulo State

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    Maria Teresa Duarte Giamas

    1992-12-01

    Full Text Available Com o objetivo de determinar a curva de crescimento segundo a expressão de von Bertalanffy, referente à espécie Astyanax bimaculatus presente na Represa de Ibitinga (21°46’S e 48°59’, foi empregado o método de contagem dos anéis etários de escamas. Para a extração destas estruturas, foi também identificada dentre seis áreas, a mais adequada do corpo, quanto à precisão de leitura, segundo WERDER e SOARES18 (1984. Foram examinados 50 exemplares, amostrados no período de julho de 1989 a junho de 1990. Observaram-se 8 classes etárias, e os comprimentos totais médios de 1 a 8 anos foram, respectivamente: 61,03 mm: 75,30 mm; 86,67 mm; 97,92  mm; 109,80 mm; 121,75 mm; 134,13 mm e 144,40 mm. A curva de crescimento determinada foi: ^Lt = 223,14 [1 – e -0,1027 (t + 1,8549

  20. Morphology of gametes, post-fertilization events and the effect of temperature on the embryonic development of Astyanax altiparanae (Teleostei, Characidae).

    Science.gov (United States)

    Dos Santos, Matheus Pereira; Yasui, George Shigueki; Xavier, Pedro Luiz Porfírio; de Macedo Adamov, Nadya Soares; do Nascimento, Nivaldo Ferreira; Fujimoto, Takafumi; Senhorini, José Augusto; Nakaghi, Laura Satiko Okada

    2016-12-01

    The aim of this study was to describe the morphology of gametes, post-fertilization events and subsequent temperature effects on the early developmental stages of the neotropical species Astyanax altiparanae. The sperm of this species presents a typical morphology of teleost sperm with a spherical head (diameter = 1.88 µm), midpiece (diameter = 0.75 µm) and a single flagellum (length = 18.67 µm). The extrusion of the second polar body and fusion of male and female pronucleus were reported for the first time in this species. Additionally, we observed the formation of the fertilization cone, which prevents polyspermic fertilization. Developmental stages at 22°C, 26°C and 30°C gave rise to fertilization rates at 91.12, 91.42 and 93.04% respectively. Hatching occurred at 25 hpf at 22°C, 16 hpf at 26°C and 11 hpf at 30°C and the hatching rates were 61.78%, 62.90% and 59.45%, respectively. At 22°C, the second polar body was extruded at ≈6 mpf and the male and female pronucleus fused at ≈10 mpf. This fundamental information is important for the field and opens up new possibilities in fish biotechnology, including micromanipulation and chromosome-set manipulation.

  1. Spatial, seasonal and ontogenetic variation in the diet of Astyanax aff. fasciatus (Ostariophysi: Characidae in an Atlantic Forest river, Southern Brazil

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    Luciano Lazzarini Wolff

    Full Text Available This study described the feeding habits of the characin Astyanax aff. fasciatus. The diet compositions of specimens from two sites (A and B on a river in Southern Brazil were compared according to the size of individuals and seasonal period. The collections were performed monthly from March 2005 to February 2006, where the stomach contents of 290 specimens were assessed. Food items for A. aff. fasciatus were basically composed of plants and insects, especially leaf fragments, seeds, fruits, filamentous algae, aquatic and terrestrial insects and insect fragments. At site A, the most common items were insect and plant fragments. Conversely at site B, plant fragments were more representative. In general, all items of animal origin showed the highest feeding index values at site A, whereas at site B detritus and grass items were more abundant. The composition of items varied seasonally, with higher diversity of items being recorded during the spring at both sites. Smaller individuals preferred items of animal origin, while the larger ones consumed mainly items of plant origin. According to its size, A. aff. fasciatus in this study may be considered a species with insectivorous tendencies when immature or herbivorous tendencies when adult. Nevertheless, its feeding habits may be flexible according to resource availability, showing wide ontogenetic, besides spatial and temporal variation.

  2. Delimiting the origin of a B chromosome by FISH mapping, chromosome painting and DNA sequence analysis in Astyanax paranae (Teleostei, Characiformes.

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    Duílio M Z de A Silva

    Full Text Available Supernumerary (B chromosomes have been shown to contain a wide variety of repetitive sequences. For this reason, fluorescent in situ hybridisation (FISH is a useful tool for ascertaining the origin of these genomic elements, especially when combined with painting from microdissected B chromosomes. In order to investigate the origin of B chromosomes in the fish species Astyanax paranae, these two approaches were used along with PCR amplification of specific DNA sequences obtained from the B chromosomes and its comparison with those residing in the A chromosomes. Remarkably, chromosome painting with the one-arm metacentric B chromosome probe showed hybridization signals on entire B chromosome, while FISH mapping revealed the presence of H1 histone and 18S rDNA genes symmetrically placed in both arms of the B chromosome. These results support the hypothesis that the B chromosome of A. paranae is an isochromosome. Additionally, the chromosome pairs Nos. 2 or 23 are considered the possible B chromosome ancestors since both contain syntenic H1 and 18S rRNA sequences. The analysis of DNA sequence fragments of the histone and rRNA genes obtained from the microdissected B chromosomes showed high similarity with those obtained from 0B individuals, which supports the intraspecific origin of B chromosomes in A. paranae. Finally, the population hereby analysed showed a female-biased B chromosome presence suggesting that B chromosomes in this species could influence sex determinism.

  3. Delimiting the origin of a B chromosome by FISH mapping, chromosome painting and DNA sequence analysis in Astyanax paranae (Teleostei, Characiformes).

    Science.gov (United States)

    Silva, Duílio M Z de A; Pansonato-Alves, José Carlos; Utsunomia, Ricardo; Araya-Jaime, Cristian; Ruiz-Ruano, Francisco J; Daniel, Sandro Natal; Hashimoto, Diogo Teruo; Oliveira, Cláudio; Camacho, Juan Pedro M; Porto-Foresti, Fábio; Foresti, Fausto

    2014-01-01

    Supernumerary (B) chromosomes have been shown to contain a wide variety of repetitive sequences. For this reason, fluorescent in situ hybridisation (FISH) is a useful tool for ascertaining the origin of these genomic elements, especially when combined with painting from microdissected B chromosomes. In order to investigate the origin of B chromosomes in the fish species Astyanax paranae, these two approaches were used along with PCR amplification of specific DNA sequences obtained from the B chromosomes and its comparison with those residing in the A chromosomes. Remarkably, chromosome painting with the one-arm metacentric B chromosome probe showed hybridization signals on entire B chromosome, while FISH mapping revealed the presence of H1 histone and 18S rDNA genes symmetrically placed in both arms of the B chromosome. These results support the hypothesis that the B chromosome of A. paranae is an isochromosome. Additionally, the chromosome pairs Nos. 2 or 23 are considered the possible B chromosome ancestors since both contain syntenic H1 and 18S rRNA sequences. The analysis of DNA sequence fragments of the histone and rRNA genes obtained from the microdissected B chromosomes showed high similarity with those obtained from 0B individuals, which supports the intraspecific origin of B chromosomes in A. paranae. Finally, the population hereby analysed showed a female-biased B chromosome presence suggesting that B chromosomes in this species could influence sex determinism.

  4. Gill histopathology and micronucleus test of Astyanax jacuhiensis (Cope, 1894 (Teleostei, Characidae to evaluate effects caused by acute exposure to aluminum

    Directory of Open Access Journals (Sweden)

    Thaís Dalzochio

    2016-02-01

    Full Text Available http://dx.doi.org/10.5007/2175-7925.2016v29n1p75 The contamination of aquatic environments by aluminum (Al is usually caused by several anthropogenic activities. Diverse morphological, physiological and biochemical alterations in aquatic organisms have been attributed to exposure to Al. In this context, the aim of this study was to investigate the effects of acute exposure to different concentrations of Al on the histology of gills and frequency of micronucleus (MN and nuclear abnormalities (NA in erythrocytes of the fish Astyanax jacuhiensis. Fish were exposed to sublethal concentrations of 0.3 mg/L and 30 mg/L of aluminum at neutral pH for 72 h. A control group was kept in filtrated water. The alterations in the gills were characterized by epithelial hyperplasia and hypertrophy, lamellar fusion, edema, epithelial lifting, aneurism and necrosis. A significant increase (p<0.05 in the frequency of abnormal lamellae was observed in groups exposed to both concentrations of Al in comparison with the control group. On the other hand, no statistical differences were observed in the frequencies of MN and NA. Although no evidence of genotoxicity was observed, the results found in the gill morphological analysis suggest that Al was toxic to the fish at both concentrations tested under neutral pH.

  5. Symbiotic diversity in the cosmopolitan genus Acacia

    Science.gov (United States)

    James K. Leary; Paul W. Singleton; Paul G. Scowcroft; Dulal Borthakur

    2006-01-01

    Acacia is the second largest genus within the Leguminosae, with 1352 species identified. This genus is now known to be polyphyletic and the international scientific community will presumably split Acacia into five new genera. This review examines the diversity of biological nitrogen fixation symbiosis within Acacia as a single genus. Due to its global importance, an...

  6. Rank and genus of 3-manifolds

    CERN Document Server

    Li, Tao

    2011-01-01

    We construct a counterexample to the Rank versus Genus Conjecture, i.e. a closed orientable hyperbolic 3-manifold with rank of its fundamental group smaller than its Heegaard genus. Moreover, we show that the discrepancy between rank and Heegaard genus can be arbitrarily large for hyperbolic 3-manifolds. We also construct toroidal such examples containing hyperbolic JSJ pieces.

  7. The genus Stixis (Capparaceae). A census

    NARCIS (Netherlands)

    Jacobs, M.

    1963-01-01

    For a long time, the genus Stixis has been known in the Indian Floras under the name Roydsia, until Pierre monographed it in 1887. Several of Pierre’s species have in the present paper been reduced, leaving Stixis a genus comprising 7 species and 1 subspecies. The genus, which is very uniform, exten

  8. Enumeration of coagulase and thermonuclease-positive Staphylococcus spp. in raw milk and fresh soft cheese: an evaluation of Baird-Parker agar, Rabbit Plasma Fibrinogen agar and the Petrifilm Staph Express count system.

    Science.gov (United States)

    Viçosa, Gabriela Nogueira; Moraes, Paula Mendonça; Yamazi, Anderson Keizo; Nero, Luís Augusto

    2010-06-01

    Staphylococcus spp. are microorganisms that are naturally present in milk and dairy products and are often associated with food-borne diseases outbreaks due to the ability of some strains to produce thermostable enterotoxins. This ability is usually associated with coagulase and thermonuclease production, characteristics that are considered in the microbiological analyses for the control of such microorganisms. The objective of this study was to evaluate the culture media and the methodologies used for the enumeration of coagulase and thermonuclease-positive Staphylococcus spp. in raw milk and fresh soft cheese. Samples of artificially contaminated milk (with coagulase-positive Staphylococcus reference strains) and samples of naturally contaminated raw milk and cheese were submitted for enumeration in Baird-Parker agar (BP), Rabbit Plasma Fibrinogen agar (RPFA) and in the Petrifilm Staph Express count system (STX). No significant differences (P > 0.05) were observed between the mean counts obtained in all of the evaluated culture media. RPFA and STX had good correlation indices between the total and typical colony counts as well as with coagulase and the thermonuclease-positive colony counts. Thus, there is a better association between coagulase and thermonuclease production to typical colony morphology developed on these culture media, leading to more accurate and reliable results than with BP, which demonstrated lower correlation indices between these counts.

  9. The genus Phytophthora anno 2012.

    Science.gov (United States)

    Kroon, Laurens P N M; Brouwer, Henk; de Cock, Arthur W A M; Govers, Francine

    2012-04-01

    Plant diseases caused by Phytophthora species will remain an ever increasing threat to agriculture and natural ecosystems. Phytophthora literally means plant destroyer, a name coined in the 19th century by Anton de Bary when he investigated the potato disease that set the stage for the Great Irish Famine. Phytophthora infestans, the causal agent of potato late blight, was the first species in a genus that at present has over 100 recognized members. In the last decade, the number of recognized Phytophthora species has nearly doubled and new species are added almost on a monthly basis. Here we present an overview of the 10 clades that are currently distinguished within the genus Phytophthora with special emphasis on new species that have been described since 1996 when Erwin and Ribeiro published the valuable monograph 'Phytophthora diseases worldwide' (35).

  10. Maximum Genus of Strong Embeddings

    Institute of Scientific and Technical Information of China (English)

    Er-ling Wei; Yan-pei Liu; Han Ren

    2003-01-01

    The strong embedding conjecture states that any 2-connected graph has a strong embedding on some surface. It implies the circuit double cover conjecture: Any 2-connected graph has a circuit double cover.Conversely, it is not true. But for a 3-regular graph, the two conjectures are equivalent. In this paper, a characterization of graphs having a strong embedding with exactly 3 faces, which is the strong embedding of maximum genus, is given. In addition, some graphs with the property are provided. More generally, an upper bound of the maximum genus of strong embeddings of a graph is presented too. Lastly, it is shown that the interpolation theorem is true to planar Halin graph.

  11. THE HYPHOMYCETE GENUS DACTYLARIA SACC.

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    MIEN A. RIFAI

    2015-11-01

    Full Text Available An emended delimitation of the genus Dactylaria Sacc. is proposed andthe two accepted species, which are non-predaceous and dematiaceous,are redescribed and illustrated. The affinity of many nematode-trappingspecies currently classified in Dactylaria with the didymosporous generaArthrobotrys Corda, Candelabrella Rifai & R. C. Cooke and Genicularia,Rifai & R. C. Cooke is discussed and the scopes of the latter genera areenlarged, and consequently several new combinations are made.

  12. Biodiversity of the genus Cladophialophora

    Science.gov (United States)

    Badali, H.; Gueidan, C.; Najafzadeh, M.J.; Bonifaz, A.; van den Ende, A.H.G. Gerrits; de Hoog, G.S.

    2008-01-01

    Cladophialophora is a genus of black yeast-like fungi comprising a number of clinically highly significant species in addition to environmental taxa. The genus has previously been characterized by branched chains of ellipsoidal to fusiform conidia. However, this character was shown to have evolved several times independently in the order Chaetothyriales. On the basis of a multigene phylogeny (nucLSU, nucSSU, RPB1), most of the species of Cladophialophora (including its generic type C. carrionii) belong to a monophyletic group comprising two main clades (carrionii- and bantiana-clades). The genus includes species causing chromoblastomycosis and other skin infections, as well as disseminated and cerebral infections, often in immunocompetent individuals. In the present study, multilocus phylogenetic analyses were combined to a morphological study to characterize phenetically similar Cladophialophora strains. Sequences of the ITS region, partial Translation Elongation Factor 1-α and β-Tubulin genes were analysed for a set of 48 strains. Four novel species were discovered, originating from soft drinks, alkylbenzene-polluted soil, and infected patients. Membership of the both carrionii and bantiana clades might be indicative of potential virulence to humans. PMID:19287540

  13. Biodiversity of the genus Cladophialophora.

    Science.gov (United States)

    Badali, H; Gueidan, C; Najafzadeh, M J; Bonifaz, A; van den Ende, A H G Gerrits; de Hoog, G S

    2008-01-01

    Cladophialophora is a genus of black yeast-like fungi comprising a number of clinically highly significant species in addition to environmental taxa. The genus has previously been characterized by branched chains of ellipsoidal to fusiform conidia. However, this character was shown to have evolved several times independently in the order Chaetothyriales. On the basis of a multigene phylogeny (nucLSU, nucSSU, RPB1), most of the species of Cladophialophora (including its generic type C. carrionii) belong to a monophyletic group comprising two main clades (carrionii- and bantiana-clades). The genus includes species causing chromoblastomycosis and other skin infections, as well as disseminated and cerebral infections, often in immunocompetent individuals. In the present study, multilocus phylogenetic analyses were combined to a morphological study to characterize phenetically similar Cladophialophora strains. Sequences of the ITS region, partial Translation Elongation Factor 1-alpha and beta-Tubulin genes were analysed for a set of 48 strains. Four novel species were discovered, originating from soft drinks, alkylbenzene-polluted soil, and infected patients. Membership of the both carrionii and bantiana clades might be indicative of potential virulence to humans.

  14. On the concordance genus of topologically slice knots

    OpenAIRE

    Hom, Jennifer

    2012-01-01

    The concordance genus of a knot K is the minimum Seifert genus of all knots smoothly concordant to K. Concordance genus is bounded below by the 4-ball genus and above by the Seifert genus. We give a lower bound for the concordance genus of K coming from the knot Floer complex of K. As an application, we prove that there are topologically slice knots with 4-ball genus equal to one and arbitrarily large concordance genus.

  15. Chemodiversity in the genus Aspergillus.

    Science.gov (United States)

    Frisvad, Jens C; Larsen, Thomas O

    2015-10-01

    Isolates of Aspergillus species are able to produce a large number of secondary metabolites. The profiles of biosynthetic families of secondary metabolites are species specific, whereas individual secondary metabolite families can occur in other species, even those phylogenetically and ecologically unrelated to Aspergillus. Furthermore, there is a high degree of chemo-consistency from isolate to isolate in a species even though certain metabolite gene clusters are silenced in some isolates. Genome sequencing projects have shown that the diversity of secondary metabolites is much larger in each species than previously thought. The potential of finding even further new bioactive drug candidates in Aspergillus is evident, despite the fact that many secondary metabolites have already been structure elucidated and chemotaxonomic studies have shown that many new secondary metabolites have yet to be characterized. The genus Aspergillus is cladistically holophyletic but phenotypically polythetic and very diverse and is associated to quite different sexual states. Following the one fungus one name system, the genus Aspergillus is restricted to a holophyletic clade that include the morphologically different genera Aspergillus, Dichotomomyces, Phialosimplex, Polypaecilum and Cristaspora. Secondary metabolites common between the subgenera and sections of Aspergillus are surprisingly few, but many metabolites are common to a majority of species within the sections. We call small molecule extrolites in the same biosynthetic family isoextrolites. However, it appears that secondary metabolites from one Aspergillus section have analogous metabolites in other sections (here also called heteroisoextrolites). In this review, we give a genus-wide overview of secondary metabolite production in Aspergillus species. Extrolites appear to have evolved because of ecological challenges rather than being inherited from ancestral species, at least when comparing the species in the different

  16. Spatial, seasonal and ontogenetic variation in the diet of Astyanax aff. fasciatus (Ostariophysi: Characidae in an Atlantic Forest river, Southern Brazil

    Directory of Open Access Journals (Sweden)

    Luciano Lazzarini Wolff

    2009-06-01

    Full Text Available This study described the feeding habits of the characin Astyanax aff. fasciatus. The diet compositions of specimens from two sites (A and B on a river in Southern Brazil were compared according to the size of individuals and seasonal period. The collections were performed monthly from March 2005 to February 2006, where the stomach contents of 290 specimens were assessed. Food items for A. aff. fasciatus were basically composed of plants and insects, especially leaf fragments, seeds, fruits, filamentous algae, aquatic and terrestrial insects and insect fragments. At site A, the most common items were insect and plant fragments. Conversely at site B, plant fragments were more representative. In general, all items of animal origin showed the highest feeding index values at site A, whereas at site B detritus and grass items were more abundant. The composition of items varied seasonally, with higher diversity of items being recorded during the spring at both sites. Smaller individuals preferred items of animal origin, while the larger ones consumed mainly items of plant origin. According to its size, A. aff. fasciatus in this study may be considered a species with insectivorous tendencies when immature or herbivorous tendencies when adult. Nevertheless, its feeding habits may be flexible according to resource availability, showing wide ontogenetic, besides spatial and temporal variation.Este estudo descreveu os hábitos alimentares do lambari Astyanax aff. fasciatus. Foram comparadas as composições alimentares de espécimes de dois sítios (A e B de um rio no sul do Brasil de acordo com o tamanho dos indivíduos e do período sazonal. As coletas foram realizadas mensalmente de março de 2005 a fevereiro de 2006, sendo o conteúdo estomacal de 290 exemplares analisado. A dieta de A. aff. fasciatus foi composta basicamente por plantas e insetos, especialmente fragmentos de folhas, sementes, frutos, algas filamentosas, insetos aquáticos e terrestres

  17. A novel role for Mc1r in the parallel evolution of depigmentation in independent populations of the cavefish Astyanax mexicanus.

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    Joshua B Gross

    2009-01-01

    Full Text Available The evolution of degenerate characteristics remains a poorly understood phenomenon. Only recently has the identification of mutations underlying regressive phenotypes become accessible through the use of genetic analyses. Focusing on the Mexican cave tetra Astyanax mexicanus, we describe, here, an analysis of the brown mutation, which was first described in the literature nearly 40 years ago. This phenotype causes reduced melanin content, decreased melanophore number, and brownish eyes in convergent cave forms of A. mexicanus. Crosses demonstrate non-complementation of the brown phenotype in F(2 individuals derived from two independent cave populations: Pachón and the linked Yerbaniz and Japonés caves, indicating the same locus is responsible for reduced pigmentation in these fish. While the brown mutant phenotype arose prior to the fixation of albinism in Pachón cave individuals, it is unclear whether the brown mutation arose before or after the fixation of albinism in the linked Yerbaniz/Japonés caves. Using a QTL approach combined with sequence and functional analyses, we have discovered that two distinct genetic alterations in the coding sequence of the gene Mc1r cause reduced pigmentation associated with the brown mutant phenotype in these caves. Our analysis identifies a novel role for Mc1r in the evolution of degenerative phenotypes in blind Mexican cavefish. Further, the brown phenotype has arisen independently in geographically separate caves, mediated through different mutations of the same gene. This example of parallelism indicates that certain genes are frequent targets of mutation in the repeated evolution of regressive phenotypes in cave-adapted species.

  18. A novel role for Mc1r in the parallel evolution of depigmentation in independent populations of the cavefish Astyanax mexicanus.

    Directory of Open Access Journals (Sweden)

    Joshua B Gross

    2009-01-01

    Full Text Available The evolution of degenerate characteristics remains a poorly understood phenomenon. Only recently has the identification of mutations underlying regressive phenotypes become accessible through the use of genetic analyses. Focusing on the Mexican cave tetra Astyanax mexicanus, we describe, here, an analysis of the brown mutation, which was first described in the literature nearly 40 years ago. This phenotype causes reduced melanin content, decreased melanophore number, and brownish eyes in convergent cave forms of A. mexicanus. Crosses demonstrate non-complementation of the brown phenotype in F(2 individuals derived from two independent cave populations: Pachón and the linked Yerbaniz and Japonés caves, indicating the same locus is responsible for reduced pigmentation in these fish. While the brown mutant phenotype arose prior to the fixation of albinism in Pachón cave individuals, it is unclear whether the brown mutation arose before or after the fixation of albinism in the linked Yerbaniz/Japonés caves. Using a QTL approach combined with sequence and functional analyses, we have discovered that two distinct genetic alterations in the coding sequence of the gene Mc1r cause reduced pigmentation associated with the brown mutant phenotype in these caves. Our analysis identifies a novel role for Mc1r in the evolution of degenerative phenotypes in blind Mexican cavefish. Further, the brown phenotype has arisen independently in geographically separate caves, mediated through different mutations of the same gene. This example of parallelism indicates that certain genes are frequent targets of mutation in the repeated evolution of regressive phenotypes in cave-adapted species.

  19. Fine-scale genetic structure patterns in two freshwater fish species, Geophagus brasiliensis (Osteichthyes, Cichlidae) and Astyanax altiparanae (Osteichthyes, Characidae) throughout a Neotropical stream.

    Science.gov (United States)

    Ferreira, D G; Lima, S C; Frantine-Silva, W; Silva, J F; Apolinário-Silva, C; Sofia, S H; Carvalho, S; Galindo, B A

    2016-10-24

    Streams are very important environments for Neotropical freshwater fish fauna, and possess a high number of species. These small drainages are also highlighted by their intrinsic biological and physicochemical features; however, knowledge on the genetic distribution of fish in these drainages is limited. Therefore, in the present study, RAPD (random amplified polymorphic DNA) and microsatellite markers were used to analyze population differentiation and gene flow of Astyanax altiparanae and Geophagus brasiliensis from three sites (high, medium, and low) throughout the Penacho stream (about 32 km long), which is a Neotropical stream. Both markers revealed higher levels of genetic diversity levels for A. altiparanae (: 90.05; HS: 0.350) compared to G. brasiliensis (: 30.43; HS: 0.118), which may be related to the particular biology of each species. AMOVA revealed significant genetic variation among populations of each species. All pairwise ΦST values were significant, ranging from 0.020 to 0.056 for A. altiparanae samples, and from 0.065 to 0.190 for G. brasiliensis samples. Bayesian clustering analysis corroborated these results and revealed clusters of both A. altiparanae (two based on RAPD data) and G. brasiliensis (two based on RAPD data and three on microsatellite data). Gene flow estimates showed that there were similar rates of migration among A. altiparanae samples and low rates of migration among some G. brasiliensis samples. These results suggest patterns of fine-scale genetic structure for both species in the Penacho stream. This information may enhance knowledge of Neotropical streams and may be useful for future management and conservation activities.

  20. Use of cholinesterase activity as a biomarker of pesticide exposure used on Costa Rican banana plantations in the native tropical fish Astyanax aeneus (Günther, 1860).

    Science.gov (United States)

    Mena, F; Azzopardi, M; Pfennig, S; Ruepert, C; Tedengren, M; Castillo, L E; Gunnarsson, J S

    2014-01-01

    In Costa Rica, thousands of tones of agricultural pesticides have been used for decades and their use is continuously increasing due to intensive and expanding production of coffee, pineapple, rice, ornamental plants and bananas. The objective of this study was to evaluate whether choline esterase (ChE) activity could be used as a biomarker of exposure to pesticides in the Costa Rican native fish Astyanax aeneus (characidae). Three methods used in order to evaluate the ChE biomarker were as follows: Laboratory studies where A. aeneus was exposed to organophosphate pesticide (ethoprophos); In situ 48 hr exposure assessment using caging experiments with fish exposed upstream and downstream of banana plantations and ChE activity estimation of in fish captured directly at sites with different degrees of pesticide exposure. Results from the laboratory studies showed that ChE activity in both brain and muscle tissue was significantly lower in fish exposed to ethoprophos than in controls. Fish from the caging experiments showed no difference in ChE activity neither in brain nor in muscle tissue between the four tested sites and was attributed to the short duration of the exposure. Asignificant difference in ChE activity was determined in muscle of fish captured from Laguna Madre de Dios compared to fish from Canal Batán. Although our laboratory results revealed that ChE activity in A. aeneus was highly responsive to ethoprophos, results from field experiments were less conclusive and showed that the captured fish showed large variability in ChE activity and that more research is needed before ChE activity can be used as reliable biomarker of pesticide exposure.

  1. Oxidative stress markers in fish (Astyanax sp. and Danio rerio) exposed to urban and agricultural effluents in the Brazilian Pampa biome.

    Science.gov (United States)

    Costa-Silva, D G; Nunes, M E M; Wallau, G L; Martins, I K; Zemolin, A P P; Cruz, L C; Rodrigues, N R; Lopes, A R; Posser, T; Franco, J L

    2015-10-01

    Aquatic ecosystems are under constant risk due to industrial, agricultural, and urban activities, compromising water quality and preservation of aquatic biota. The assessment of toxicological impacts caused by pollutants to aquatic environment using biomarker measurements in fish can provide reliable data to estimate sublethal effects posed by chemicals in contaminated areas. In this study, fish (Astyanax sp. and Danio rerio) exposed to agricultural and urban effluents at the Vacacaí River, Brazil, were tested for potential signs of aquatic contamination. This river comprehends one of the main watercourses of the Brazilian Pampa, a biome with a large biodiversity that has been neglected in terms of environmental and social-economic development. Sites S1 and S2 were chosen by their proximity to crops and wastewater discharge points, while reference site was located upstream of S1 and S2, in an apparently non-degraded area. Fish muscle and brain tissues were processed for determination of acetylcholinesterase as well as oxidative stress-related biomarkers. The results showed signs of environmental contamination, hallmarked by significant changes in cholinesterase activity, expression of metallothionein, antioxidant enzymes, glutathione levels, and activation of antioxidant/cell stress response signaling pathways in fish exposed to contaminated sites when compared to reference. Based on these results, it is evidenced that urban and agricultural activities are posing risk to the environmental quality of water resources at the studied area. It is also demonstrated that cell stress biomarkers may serve as important tools for biomonitoring and development of risk assessment protocols in the Pampa biome.

  2. Early lens ablation causes dramatic long-term effects on the shape of bones in the craniofacial skeleton of Astyanax mexicanus.

    Science.gov (United States)

    Dufton, Megan; Hall, Brian K; Franz-Odendaal, Tamara A

    2012-01-01

    The Mexican tetra, Astyanax mexicanus, exists as two morphs of a single species, a sighted surface morph and a blind cavefish. In addition to eye regression, cavefish have an increased number of taste buds, maxillary teeth and have an altered craniofacial skeleton compared to the sighted morph. We investigated the effect the lens has on the development of the surrounding skeleton, by ablating the lens at different time points during ontogeny. This unique long-term study sheds light on how early embryonic manipulations on the eye can affect the shape of the adult skull more than a year later, and the developmental window during which time these effects occur. The effects of lens ablation were analyzed by whole-mount bone staining, immunohistochemisty and landmark based morphometric analyzes. Our results indicate that lens ablation has the greatest impact on the skeleton when it is ablated at one day post fertilisation (dpf) compared to at four dpf. Morphometric analyzes indicate that there is a statistically significant difference in the shape of the supraorbital bone and suborbital bones four through six. These bones expand into the eye orbit exhibiting plasticity in their shape. Interestingly, the number of caudal teeth on the lower jaw is also affected by lens ablation. In contrast, the shape of the calvariae, the length of the mandible, and the number of mandibular taste buds are unaltered by lens removal. We demonstrate the plasticity of some craniofacial elements and the stability of others in the skull. Furthermore, this study highlights interactions present between sensory systems during early development and sheds light on the cavefish phenotype.

  3. New species of Cacatuocotyle (Monogenoidea, Dactylogyridae) parasitizing the anus and the gill lamellae of Astyanax aeneus (Pisces, Ostariophysi: Characidae) from the Rio Lacantún basin in the Biosphere Reserve of Montes Azules, Chiapas, Mexico.

    Science.gov (United States)

    Franco, Edgar F Mendoza; Caspeta-Mandujano, J M; Salgado-Maldonado, G

    2013-01-01

    As part of a biological inventory of the Rio Lacantún basin in the Biosphere Reserve of Montes Azules from Chiapas State (southeastern, Mexico), the following monogenoid ectoparasites infecting the external surface of the anal opening and the gill lamellae of the freshwater fish Astyanax aeneus (Characidae) in ten streams were found: Cacatuocotyle chajuli sp. nov. (anus), Cacatuocotyle exiguum sp. nov., and Cacatuocotyle sp. (gill lamellae). C. chajuli is differentiated from its single congener, Cacatuocotyle paranaensis (Boeger et al. Syst Parasitol 36:75-78, 1997), from the gills of Characidium lanei (Characidae) from Paraná Brazil, in having a noticeably V-shaped haptoral bar and larger hooks and anchors. C. exiguum differs from these two latter species in the size of its anchors. Illustrations and data on morphological and biometric variability of individual specimens of C. chajuli and C. exiguum from different streams are provided. The present data support the statement about three species of Astyanax, which harbor the richest monogenoidean diversity in the Neotropics with a total of 18 species reported up to now. Occurrences of species of Cacatuocotyle on different sites of infection on three distant host species [including a Neotropical cichlid (Cichlidae) species] suggest that these monogenoideans switching to new hosts can result in the availability of potential hosts within the same habitat instead of showing signs of preferential switching between closely related hosts or on their respective microhabitats.

  4. Aspidonepsis (Asclepiadaceae, a new southern African genus

    Directory of Open Access Journals (Sweden)

    A. Nicholas

    1992-12-01

    Full Text Available Aspidonepsis, an endemic southern African genus, is described and compared to the closely allied genus Aspidoglossum. This newly described genus is composed of two subgenera, Aspidonepsis and Unguilobium. consisting of three and two species respectively.  Asclepias diploglossa, A. flava, A. cognata and A. reneensis are transferred to Aspidonepsis. and A. shebae is newly described. All species are discussed, illustrated and a key is given to aid in their identification.

  5. The genus Lolium; taxonomy and genetic resources.

    OpenAIRE

    Loos, B.P.

    1994-01-01

    Several aspects of variation within the genus Lolium, and more in detail within Lolium perenne (perennial ryegrass) have been highlighted. As the results are extensively discussed in each chapter, the general discussion is focused on two aspects of the research.SpeciationIt is clear that the genus Lolium is a very variable genus. The variation within the species reduces the clarity of separation of the species. Stebbins (1956) found the differences between Lolium and Festuca not sufficient to...

  6. THE GENUS DURIO Adans. (Bombac.

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    A. J. G. H. KOSTERMANS

    2015-11-01

    Full Text Available The genus Durio comprises, as far as known, 27 species. The centre ofdistribution is Borneo with 19 species, followed by Malaya with 11 spe-cies and Sumatra with 7 species. It is likely, when Sumatra will be betterexplored, that this island will prove to have many more species. An exclave of the area of distribution is found in Burma, where one endemic species occurs. The common Durio zibethinus Murr. probably originated in Borneo or in Sumatra. It is now widely cultivated outside of its former area and in many places it has become spontaneous.The genus Durio is subdivided into two subgenera: Durio and BoschiaKosterm. & Soegeng, according to the way of dehiscence of the anthers(with a longitudinal slit in the former, with an apical pore in the latter.A key to the species is proposed. A map is added, to show distribution and endemism. Each species is amply described and provided with a drawing . Economic and ecological data are given.

  7. Evolution of the Genus Homo

    Science.gov (United States)

    Tattersall, Ian; Schwartz, Jeffrey H.

    2009-05-01

    Definition of the genus Homo is almost as fraught as the definition of Homo sapiens. We look at the evidence for “early Homo,” finding little morphological basis for extending our genus to any of the 2.5-1.6-myr-old fossil forms assigned to “early Homo” or Homo habilis/rudolfensis. We also point to heterogeneity among “early African Homo erectus,” and the lack of apomorphies linking these fossils to the Asian Homo erectus group, a cohesive regional clade that shows some internal variation, including brain size increase over time. The first truly cosmopolitan Homo species is Homo heidelbergensis, known from Africa, Europe, and China following 600 kyr ago. One species sympatric with it included the >500-kyr-old Sima de los Huesos fossils from Spain, clearly distinct from Homo heidelbergensis and the oldest hominids assignable to the clade additionally containing Homo neanderthalensis. This clade also shows evidence of brain size expansion with time; but although Homo neanderthalensis had a large brain, it left no unequivocal evidence of the symbolic consciousness that makes our species unique. Homo sapiens clearly originated in Africa, where it existed as a physical entity before it began (also in that continent) to show the first stirrings of symbolism. Most likely, the biological underpinnings of symbolic consciousness were exaptively acquired in the radical developmental reorganization that gave rise to the highly characteristic osteological structure of Homo sapiens, but lay fallow for tens of thousands of years before being “discovered” by a cultural stimulus, plausibly the invention of language.

  8. The genus Allium. Part 2.

    Science.gov (United States)

    Fenwick, G R; Hanley, A B

    1985-01-01

    Allium is a genus of some 500 species belonging to the family Liliaceae. However only a few of these are important as food plants, notably onion, garlic, chive, leek, and rakkyo. Such plants have been used for many centuries for the pungency and flavoring value, for their medicinal properties, and, in some parts of the world, their use also has religious connotations. The flavors of members of the genus Alliums, in addition to having certain characteristics, are also complex, being derived enzymically from a number of involatile precursors. In addition to there being variation of flavor between different alliums, there are also considerable changes that occur as a result of cooking and processing. Of course, these are of importance to the consumer and food technologist-processor. The review will introduce the subject by an historical perspective and will set this against data on the present cultivation and usage of commercially cultivated alliums. The chemical composition of these plants will be discussed, emphasis being given to nonvolatile constituents which are, perhaps, less often considered. Discussion of the volatile constituents, which will include mention of the methods currently used for their analysis and for the determination of "flavor strength", will be mainly concerned with literature taken from the last 5 years. In considering the extent and nature of allium cultivation and processing, factors affecting the nutritional value and quality will be highlighted. The medicinal properties of garlic and onion oils have been much studied over the last decade and the review will include critical assessment of this area and also will touch on the more general properties (antimicrobial, antifungal, antibacterial, and insecticidal) of these oils. Finally mention will be made of the antinutritional, toxic, or otherwise undesirable effects of alliums, for example, as inadvertent components of animal diets, tainting of milk and other food products. It is our

  9. Resurrection of the genus Haplanthus (Acanthaceae: Andrographinae)

    NARCIS (Netherlands)

    Gnanasekaran, G.; Murthy, G.V.S.; Deng, Y.F.

    2016-01-01

    A systematic morphological study of Andrographis (Acanthaceae: Andrographinae) in India has revealed that the genus Haplanthus is distinct from Andrographis. We resurrect the genus Haplanthus here with four species, one of which contains three varieties. Five new combinations are proposed: H. laxifl

  10. A monograph of the genus Evolvulus

    NARCIS (Netherlands)

    Ooststroom, van S.J.

    1934-01-01

    The great difficulties arising in the identification of a number of plants belonging to the genus Evolvulus, which plants were found in several recent collections of Convolvulaceae and were kindly entrusted to me for study, induced me to submit this genus to a further examination. It soon proved how

  11. A new genus of Lindsaeoid ferns

    NARCIS (Netherlands)

    Kramer, K.U.

    1957-01-01

    In revising the New World representatives of the genus Lindsaea, the author came across a fern specimen from Borneo preserved in the Rijksherbarium, Leiden, that did not seem to fit into any described genus. It had been described as Schizoloma stortii v. A. v. R., but in the author’s opinion the gen

  12. A monograph of the Genus Aristida

    NARCIS (Netherlands)

    Henrard, J.Th.

    1929-01-01

    In a preliminary work: „A critical Revision of the genus Aristida”, I have given a review of all the hitherto described species of this genus with the citation of the literature, the exact copies of the authentic descriptions and the figures of the spikelet-characters, taken from the type specimens

  13. New Forms in the genus Erebia (Lepidoptera)

    NARCIS (Netherlands)

    Eisner, C.

    1946-01-01

    A revision of the material belonging to the genus Erebia Dalman in the Rijksmuseum van Natuurlijke Historie at Leiden, mainly based on the "Monograph of the genus Erebia" by B. C. S. Warren (London, 1936), induced me to describe a number of new subspecies and aberrations, and to make some remarks on

  14. New Forms in the genus Erebia (Lepidoptera)

    NARCIS (Netherlands)

    Eisner, C.

    1946-01-01

    A revision of the material belonging to the genus Erebia Dalman in the Rijksmuseum van Natuurlijke Historie at Leiden, mainly based on the "Monograph of the genus Erebia" by B. C. S. Warren (London, 1936), induced me to describe a number of new subspecies and aberrations, and to make some remarks on

  15. Cytotaxonomic studies in the genus Campanula

    NARCIS (Netherlands)

    Gadella, Th.W.J.

    1964-01-01

    De Candolle (1830) divided the genus Campanula into two large sections on basis of the presence or absence of calyx-appendages between the calyx-lobes. Boissier (1875) attached great value to the mode of dehiscence of the capsule, and divided the genus into two sections. None of the existing classif

  16. A monograph of the Genus Aristida

    NARCIS (Netherlands)

    Henrard, J.Th.

    1929-01-01

    In a preliminary work: „A critical Revision of the genus Aristida”, I have given a review of all the hitherto described species of this genus with the citation of the literature, the exact copies of the authentic descriptions and the figures of the spikelet-characters, taken from the type specimens

  17. A taxonomic revision of the genus Podocarpus

    NARCIS (Netherlands)

    Laubenfels, de D.J.

    1985-01-01

    In connection with the forthcoming revision of the Coniferae for the Flora Malesiana, the author thought it necessary to revise the genus Podocarpus. Although this genus has a substantial representation in Malesia (30 species), the revision is too involved to be appropriate with the Flora Malesiana

  18. Sugawara construction for higher genus Riemann surfaces

    Science.gov (United States)

    Schlichenmaier, Martin

    1999-04-01

    By the classical genus zero Sugawara construction one obtains representations of the Virasoro algebra from admissible representations of affine Lie algebras (Kac-Moody algebras of affine type). In this lecture, the classical construction is recalled first. Then, after giving a review on the global multi-point algebras of Krichever-Novikov type for compact Riemann surfaces of arbitrary genus, the higher genus Sugawara construction is introduced. Finally, the lecture reports on results obtained in a joint work with O. K. Sheinman. We were able to show that also in the higher genus, multi-point situation one obtains (from representations of the global algebras of affine type) representations of a centrally extended algebra of meromorphic vector fields on Riemann surfaces. The latter algebra is a generalization of the Virasoro algebra to higher genus.

  19. Atividades de lactato desidrogenase e malato desidrogenase de Astyanax bimaculatus (lambari da bacia hidrográfica do rio Una como biomarcadoras de impacto ambiental

    Directory of Open Access Journals (Sweden)

    Anne Caroline Ribeiro

    2015-11-01

    Full Text Available Os peixes vivem todo o ciclo de vida na água e recebem a influência dos seus componentes físico-químicos e biológicos ao longo do tempo. As atividades de lactato desidrogenase (LDH e malato desidrogenase (MDH de organismos aquáticos podem ser alteradas devido à presença de poluentes na água. O objetivo deste estudo foi determinar se as atividades de LDH e MDH nas brânquias e no fígado de Astyanax bimaculatus (lambari do rabo amarelo podem ser utilizadas como biomarcadoras do impacto ambiental na bacia hidrográfica do rio Una (SP. Para isso, esses lambaris foram coletados em três corpos d’água dessa bacia, denominados p1 (rio Itaim, p2 (córrego à beira da Estrada Municipal de Remédios e p3 (lago na Estrada Municipal Dr. José Luiz Cembranelli. As brânquias e o fígado foram homogeneizados e, a seguir, esse material foi centrifugado e o sobrenadante foi utilizado para determinação das atividades de LDH e MDH, através do método espectrofotométrico que determina a taxa de oxidação de NADH. As atividades de LDH e MDH no fígado e de MDH branquial não foram estatisticamente diferentes nos lambaris coletados nos três locais. No tecido branquial a atividade de LDH foi inferior nos peixes de p3 em relação aos de p1. Essa inibição da atividade de LDH, bem como a qualidade inferior da água nesse ponto, sugerem a ocorrência de poluentes nessa água. Conclui-se que LDH branquial de lambari possui potencial para utilização como marcador bioquímico de impacto ambiental no rio Una.

  20. Reproductive biomarkers responses induced by xenoestrogens in the characid fish Astyanax fasciatus inhabiting a South American reservoir: An integrated field and laboratory approach

    Energy Technology Data Exchange (ETDEWEB)

    Prado, Paula S.; Pinheiro, Ana Paula B. [Departamento de Morfologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, UFMG, Belo Horizonte, C.P. 486, 30161-970, Minas Gerais (Brazil); Bazzoli, Nilo [Programa de Pós-Graduação em Zoologia de Vertebrados, Pontifícia Universidade Católica de Minas Gerais, PUC Minas, Belo Horizonte 30535-610, Minas Gerais (Brazil); Rizzo, Elizete, E-mail: ictio@icb.ufmg.br [Departamento de Morfologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, UFMG, Belo Horizonte, C.P. 486, 30161-970, Minas Gerais (Brazil)

    2014-05-01

    Field studies evaluating the effects of endocrine disruption chemicals (EDCs) on the fish reproduction are scarce worldwide. The goal of this study was to assess hepatic levels of vitellogenin (Vtg), zona radiata proteins (Zrp) and insulin-like growth factors (IGF-I and IGF-II), and relating them to reproductive endpoints in a wild fish population habiting a reservoir that receive domestic sewage, agricultural and industrial residues. Adult fish Astyanax fasciatus were sampled during the reproductive season in five sites from the Furnas Reservoir, Grande River, and Paraguay–Paraná basin. As a control to field data, fish were experimentally exposed via dietary intake, to oestradiol benzoate (OB) for 7 days. Fish from site with little anthropogenic interference showed hepatic levels of Vtg, Zrp and IGF-I and IGF-II similar to those from the non-treated experimental group. In sites located immediately downstream from the municipal wastewater discharges, the water total oestrogen was >120 ng/l, and male fish displayed increased Vtg and Zrp and decreased IGF-I levels similar to OB treated fish. In females, levels of Vtg, Zrp, IGF-I and IGF-II suggest an impairment of final oocyte maturation and spawning, as also detected by frequency of over-ripening, follicular atresia and fecundity. At the sites that receive agricultural and industrial residues, the water total oestrogen was <50 ng/l and females showed decreased Zrp and increased IGF-II levels associated to reduced diameter of vitellogenic follicles, indicating an inhibition of oocyte growth. Overall, the current study reports oestrogenic contamination impairing the reproduction of a wild fish from a hydroeletric reservoir and, the data contribute to improving the current knowledge on relationship between hepatic Vtg, Zrp and IGF-I and IGF-II, and reproductive endpoints in a teleost fish. In addition, our data point out novel reproductive biomarkers (IGF-I, IGF-II and over-ripening) to assessing xenoestrogenic

  1. A new species of Auriculostoma (Digenea: Allocreadiidae) in the Mexican tetra Astyanax mexicanus (Actinopterygii: Characidae) from Central Veracruz, Mexico, described with the use of morphological and molecular data.

    Science.gov (United States)

    Razo-Mendivil, Ulises; Mendoza-Garfias, Berenit; de León, Gerardo Pérez-Ponce; Rubio-Godoy, Miguel

    2014-06-01

    Auriculostoma totonacapanensis n. sp. is described from the Mexican tetra, Astyanax mexicanus (Actinopterygii, Characidae) collected in a tributary creek of the Bobos River in Filipinas, Veracruz, Mexico. The new species is set apart from all congeners by the combination of some morphological characters such as the testes position (oblique in most specimens), the ventral to oral sucker ratio (1:1.2 × 1:1.1), the cirrus sac originating at the ovarian region, and by having vitelline follicles not confluent in the posttesticular region. Auriculostoma totonacapanensis n. sp. closely resembles Auriculostoma platense (Szidat, 1954) Scholz, Aguirre-Macedo, and Choudhury, 2004 and Auriculostoma diagonale Curran, Tkach and Overstreet, 2011 by possessing oblique testes; however, it differs from both species by possessing a genital pore located at level of the cecal bifurcation and by having vitelline follicles extending anteriorly up to the cecal bifurcation level, instead of a genital pore located between the anterior margin of the ventral sucker and cecal bifurcation, and vitelline follicles extending anteriorly to the mid level of the esophagus as in A. platense or to the pharynx level as in A. diagonale. Additionally, the new species differs from A. diagonale by having vitelline follicles not confluent or scarcely confluent in the posttesticular region rather than extensively confluent. Scanning electron microscopy micrographs of the new species demonstrated the presence of a single pair of muscular lobes on either side of the oral sucker, with a broad base, stretching from the ventrolateral to the dorsolateral side. Maximum parsimony and Bayesian inference analyses of the 28S rRNA gene sequences placed A. totonacapanensis as sister species of Auriculostoma astyanace Scholz, Aguirre-Macedo, and Choudhury, 2004 . Nucleotide variation between A. totonacapanensis and A. astyanace was 2.0% and 3.6% for the 28S rRNA gene and ITS2 sequences, respectively. Sequence variation

  2. Phytochemistry and Pharmacology of the Genus Tovomita.

    Science.gov (United States)

    Epifano, Francesco; Specchiulli, Maria Carmela; Taddeo, Vito Alessandro; Fiorito, Serena; Genovese, Salvatore

    2015-06-01

    The genus Tovomita (Fam. Clusiaceae) comprises 45 species mainly found in tropical regions of Central and South America. Most of the species of the title genus have been used for centuries as natural remedies. Phytochemicals isolated from Tovomita spp. include prenylated and unprenylated benzophenones and xanthones. The aim of this review is to examine in detail from a phytochemical and pharmacological point of view what is reported in the past and current literature about the properties of phytopreparations and individual active principles obtained from plants belonging to the Tovomita genus.

  3. Keanekaragaman metabolit sekunder Genus Artocarpus (Moraceae

    Directory of Open Access Journals (Sweden)

    ALIEFMAN HAKIM

    2011-11-01

    Full Text Available Hakim A. 2011. Keanekaragaman metabolit sekunder Genus Artocarpus (Moraceae. Bioteknologi 8: 86-98. Beberaapa spesies dari genus Artocarpus (Moraceae telah diteliti kandungan bahan alamnya. Metabolit sekunder yang berhasil diisolasi dari genus Artocarpus terdiri dari terpenoid, flavonoid, stilbenoid, arilbenzofuran, neolignan, dan adduct Diels-Alder. Kelompok flavonoid merupakan senyawa yang paling banyak ditemukan dari tumbuhan Artocarpus. Senyawa flavonoid yang telah berhasil diisolasi dari tumbuhan Artocarpus memiliki kerangka yang beragam seperti calkon, flavanon, flavan-3-ol, flavon sederhana, prenilflavon, oksepinoflavon, piranoflavon, dihidrobenzosanton, furanodi hidrobenzosanton, piranodihidrobenzosanton, kuinonosanton, siklolopentenosanton, santonolid, dihidrosanton.

  4. Genus llex L.: Phytochemistry, Ethnopharmacology, and Pharmacology

    Institute of Scientific and Technical Information of China (English)

    Fan Yi; Xiao-ling Zhao; Yong Peng; Pei-gen Xiao

    2016-01-01

    The genus llex L. has been used as remedies in traditional Chinese medicine in Aquifoliaceae and beverages for thousands of years due to abundant pharmaceutical bioactivities. There are 600 species in genus llex L. containing various compounds such as terpenoids, saponins, glycosides, etc. Three species, I. cornuta, I. chinensis, and I. rotunda have been admitted in Chinese Pharmacopoeia 2015 to treat dyspepsia, stomatitis, and hyperactivity cough and protect the liver and kidney. Recent studies showed that several species have been daily drunk to promote human health and prevent cardiovascular diseases in the folk. Here we reviewed the genus llex L. in phytochemistry, ethnopharmacology, and pharmacology.

  5. Beta genus papillomaviruses and skin cancer.

    Science.gov (United States)

    Howley, Peter M; Pfister, Herbert J

    2015-05-01

    A role for the beta genus HPVs in keratinocyte carcinoma (KC) remains to be established. In this article we examine the potential role of the beta HPVs in cancer revealed by the epidemiology associating these viruses with KC and supported by oncogenic properties of the beta HPV proteins. Unlike the cancer associated alpha genus HPVs, in which transcriptionally active viral genomes are invariably found associated with the cancers, that is not the case for the beta genus HPVs and keratinocyte carcinomas. Thus a role for the beta HPVs in KC would necessarily be in the carcinogenesis initiation and not in the maintenance of the tumor. Copyright © 2015 Elsevier Inc. All rights reserved.

  6. The genus of a type of graph

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    Based on the joint tree model introduced by Liu, the genera of further types of graphs not necessary to have certain symmetry can be obtained. In this paper, we obtain the genus of a new type of graph with weak symmetry. As a corollary, the genus of complete tripartite graph K n,n,l (l≥n≥2) is also derived. The method used here is more direct than those methods, such as current graph, used to calculate the genus of a graph and can be realized in polynomial time.

  7. Cytogenetic comparison between two allopatric populations of Astyanax altiparanae Garutti et Britski, 2000 (Teleostei, Characidae), with emphasis on the localization of 18S and 5S rDNA

    Science.gov (United States)

    Pacheco, Rosiley Berton; da Rosa, Renata; Giuliano-Caetano, Lucia; Júlio Jr., Horácio Ferreira; Dias, Ana Lúcia

    2011-01-01

    Abstract Two populations of Astyanax altiparanae (Garutti & Britski, 2000) of the Água dos Patos stream/SP and lake Igapó/PR were analyzed. All individuals showed 2n = 50, however, different karyotypic formulae were observed. The population of the Água dos Patos stream showed 8m +24sm+6st+12a (NF=88) and the population of lake Igapó, 8m+28sm+4st+10a (NF=90). Nucleolus organizing regions (AgNORs) were observed in the terminal position on the short and long arm of different chromosomes of both populations, showing a variation from 3 to 4 chromosomes. Fluorescent in situ hybridization (FISH) using 18S rDNA probes revealed only one pair of chromosomes with fluorescent signals in the terminal site on the short arm in the Igapó lake population, while the population of Água dos Patos stream showed 4 fluorescence terminal signals, characterizing a system of simple and multiple NORs, respectively. 5S rDNA fluorescent signals were detected in the interstitial position of a pair of chromosomes in the two studied populations. Some AgNOR sites revealed to be GC-rich when stained with Chromomycin A3 (CMA3), however, AT positive regions were not observed. The data obtained show that, despite the conservation of the diploid number and location of 5S DNAr, differences in both the distribution of 18S rDNA and karyotypic formula among the populations were found, thus corroborating the existing data on chromosome variability in Astyanax altiparanae that can be significant for cytotaxonomy in this group. PMID:24260632

  8. Taxonomy of the genus Passerina (Thymelaeaceae

    Directory of Open Access Journals (Sweden)

    C. L. Bredenkamp

    2003-12-01

    Full Text Available Passerina L. is mainly a southern African genus, comprising 20 species and four subspecies. A few species occur along the Great Escarpment, two extend into Zimbabwe and Mozambique, but most are concentrated in the Cape Floristic Region. Palynological. macromorphological and anatomical evidence was used in the delimitation of the genus and its infrageneric taxa. A cladistic study supports Passerina as a monophyletic genus. A genus treatment, key to species and a full species treatment are given. Each species treatment includes a taxonomic diagnosis, description and notes on taxonomy, etymology, economic value and distribution. Illustrations of representative species are provided and distribution maps are included for each species.  P. esterhuyseniae Bredenk. & A.E.van Wyk is newly described. A list of excluded species names highlights the previous cosmopolitan taxonomic interpretation of Passerina. as many names are now in synony my under other genera of the Thymelaeaceae.

  9. Synaptospory in the fern genus Pyrrosia (Polypodiaceae)

    NARCIS (Netherlands)

    Uffelen, van Gerda A.

    1985-01-01

    The correlation between sporoderm sculpture and life form of the sporophyte as postulated by Kramer (1977) is investigated for the fern genus Pyrrosia. This correlation is not found in Pyrrosia but may be present in other fern groups.

  10. Synaptospory in the fern genus Pyrrosia (Polypodiaceae)

    NARCIS (Netherlands)

    Uffelen, van Gerda A.

    1983-01-01

    The correlation between sporoderm sculpture and life form of the sporophyte as postulated by Kramer (1977) is investigated for the fern genus Pyrrosia. This correlation is not found in Pyrrosia but may be present in other fern groups.

  11. Phylogeny and taxonomy of the genus Gliocephalotrichum

    NARCIS (Netherlands)

    Lombard, L.; Serrato-Diaz, L.M.; Cheewangkoon, R.; French-Monar, R.D.; Decock, C.; Crous, P.W.

    2014-01-01

    Species in the genus Gliocephalotrichum (= Leuconectria) (Hypocreales, Nectriaceae) are soilborne fungi, associated with post-harvest fruit spoilage of several important tropical fruit crops. Contemporary taxonomic studies of these fungi have relied on morphology and DNA sequence comparisons of the

  12. Phylogeny and taxonomy of the genus Gliocephalotrichum

    NARCIS (Netherlands)

    Lombard, L.; Serrato-Diaz, L. M.; Cheewangkoon, R.; French-Monar, R. D.; Decock, C.; Crous, P. W.

    Species in the genus Gliocephalotrichum (= Leuconectria) (Hypocreales, Nectriaceae) are soilborne fungi, associated with post-harvest fruit spoilage of several important tropical fruit crops. Contemporary taxonomic studies of these fungi have relied on morphology and DNA sequence comparisons of the

  13. Monograph of the genus Phylacium (Leguminosae)

    NARCIS (Netherlands)

    Bresser, Mirjam

    1978-01-01

    In the genus Phylacium 2 species are recognized. Special attention is paid to the morphology of the inflorescence; full descriptions are given with plates and a map, showing the distribution of both species.

  14. Taxonomic revision of the genus Acanthephippium (Orchidaceae)

    NARCIS (Netherlands)

    Thomas, S.A.

    1997-01-01

    This is a revision of the genus Acanthephippium Blume. Eleven species are recognised. Seven names are here for the first time reduced to synonymy (A. lycaste, A. odoratum, A. papuanum, A. pictum, A. simplex, A. sinense, and A. thailandicum).

  15. Taxonomy of the genus Passerina (Thymelaeaceae

    Directory of Open Access Journals (Sweden)

    C. L. Bredenkamp

    2003-12-01

    Full Text Available Passerina L. is mainly a southern African genus, comprising 20 species and four subspecies. A few species occur along the Great Escarpment, two extend into Zimbabwe and Mozambique, but most are concentrated in the Cape Floristic Region. Palynological. macromorphological and anatomical evidence was used in the delimitation of the genus and its infrageneric taxa. A cladistic study supports Passerina as a monophyletic genus. A genus treatment, key to species and a full species treatment are given. Each species treatment includes a taxonomic diagnosis, description and notes on taxonomy, etymology, economic value and distribution. Illustrations of representative species are provided and distribution maps are included for each species.  P. esterhuyseniae Bredenk. & A.E.van Wyk is newly described. A list of excluded species names highlights the previous cosmopolitan taxonomic interpretation of Passerina. as many names are now in synony my under other genera of the Thymelaeaceae.

  16. Phylogeny and taxonomy of the genus Gliocephalotrichum

    NARCIS (Netherlands)

    Lombard, L.; Serrato-Diaz, L.M.; Cheewangkoon, R.; French-Monar, R.D.; Decock, C.; Crous, P.W.

    2014-01-01

    Species in the genus Gliocephalotrichum (= Leuconectria) (Hypocreales, Nectriaceae) are soilborne fungi, associated with post-harvest fruit spoilage of several important tropical fruit crops. Contemporary taxonomic studies of these fungi have relied on morphology and DNA sequence comparisons of the

  17. Cosmetic crossings of genus one knots

    CERN Document Server

    Balm, Cheryl

    2011-01-01

    We show that for genus one knots the Alexander polynomial and the homology of the double cover branching over the knot provide obstructions to cosmetic crossings. As an application we prove the nugatory crossing conjecture for the negatively twisted, positive Whitehead doubles of all knots. We also verify the conjecture for several families of pretzel knots and all genus one knots with up to 10 crossings.

  18. Kops genus - en værkstedsrapport

    DEFF Research Database (Denmark)

    Gudiksen, Asgerd

    2008-01-01

     Inden for Ømålsområdet optræder ordet kop både i genus femininum, masku­linum og neutrum. På Sjælland, hvor trekønssystemet er under af­vikling, kan ordet desuden være genus commune. Der kan konstateres en vis dialektgeografisk fordeling af de tre (fire) genera, men især på Sjælland er...

  19. Taxonomic novelties in the genus Campylospermum (Ochnaceae)

    OpenAIRE

    Bissiengou, P.; Chatrou, L.W.; Wieringa, J. J.; Sosef, M.S.M.

    2013-01-01

    Four new species, one with two subspecies, of the genus Campylospermum are described, all endemic or sub-endemic to Gabon. These are C. auriculatum, C. gabonensis, C. gabonensis subsp. australis, C. glaucifolium and C. occidentalis. Distribution maps and scans of the holotypes are provided as well as preliminary IUCN Red List assessments. New combinations for nine species formerly assigned to the genus Ouratea and/or Gomphia are proposed: C. andongensis, C. glomeratum, C. longestipulatum, C. ...

  20. "Kriitiline arhitektuur" ja selle vastased / George Baird

    Index Scriptorium Estoniae

    Baird, George

    2010-01-01

    Ameerika kriitilisest arhitektuurist ja uuest projektiivsest arhitektuurist, mida ei saa arendada ilma projektiivse teooria toeta. Selleta muutuks uus arhitektuur autori arvates kiiresti lihtsalt pragmaatiliseks ja lihtsalt dekoratiivseks

  1. Genus distribution of ladder type and cross type graphs

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    In this paper a method is given to calculate the explicit expressions of embedding genus distribution for ladder type graphs and cross type graphs. As an example, we refind the genus distri- bution of the graph Jn which is the first class of graphs studied for genus distribution where its genus depends on n.

  2. Genus distribution of ladder type and cross type graphs

    Institute of Scientific and Technical Information of China (English)

    WAN LiangXia; FENG KeQin; LIU YanPei; WANG DianJun

    2009-01-01

    In this paper a method is given to calculate the explicit expressions of embedding genus distribution for ladder type graphs and cross type graphs.As an example,we refind the genus distribution of the graph Jn which is the first class of graphs studied for genus distribution where its genus depends on n.

  3. Population structure and reproductive biology of Astyanax gymnodontus (Characiformes: Characidae), a poorly known endemic fish of the Iguaçu River basin, Brazil.

    Science.gov (United States)

    Baumgartner, Matheus Tenório; da Silva, Pedro Rogério Leandro; Baumgartner, Gilmar

    2016-03-01

    Success in fish breeding depends on reproduction intensity, periodicity and the place where it occurs. Information about fish species reproduction is important to assist managers, and to determine conservation and management strategies. The fish assemblage of the Iguaçu River basin is already known for its high endemism, and despite this privilege, the large number of dams built along it, threat this particular biodiversity. Astyanax gymnodontus is an endemic fish species and studies on its population structure and reproductive biology are important, since they represent the first step for further community studies. Our objective was to evaluate some aspects of the population structure and reproductive biology of A. gymnodontus in the influence area of Salto Santiago dam, Iguaçu River, Paraná State, Brazil. Sampling was made monthly from July 2003 to June 2005, and bimonthly from July 2005 to March 2013, at five sites in the influence area of Salto Santiago dam. Fishes were collected using 10 m length gillnets with meshes ranging from 2.5 to 6.0 cm between non-adjacent knots and trammel nets with inner meshes of 6.0 cm between non-adjacent knots. Nets were arranged on surface, bottom and margins of each site, exposed for 24 h. Additional drags on littoral areas were performed from January to March and October to December from 2009 to 2011, with 50.0 m nets, 0.5 cm mesh size, for juveniles capture. We captured and analyzed 21 932 individuals, being 9 249 females and 12 683 males, representing 42.2 % and 57.8 %, respectively. The average body length was 8.8 cm for females and 8.3 cm for males. The average weight was 18.8 g for females and 16.0 g for males. Sex ratio calculated for the entire period was 1.8 males/female. Males were more abundant than females in 73.2 % of samples and significant differences were observed in 35.3 % of samples. The estimated length at first maturity (SL(50)) was 6.4 cm for females and 6.2 cm for males. We suggest that sexual

  4. Genomic diversity within the haloalkaliphilic genus Thioalkalivibrio

    Science.gov (United States)

    Ahn, Anne-Catherine; Meier-Kolthoff, Jan P.; Overmars, Lex; Richter, Michael; Woyke, Tanja; Sorokin, Dimitry Y.

    2017-01-01

    Thioalkalivibrio is a genus of obligate chemolithoautotrophic haloalkaliphilic sulfur-oxidizing bacteria. Their habitat are soda lakes which are dual extreme environments with a pH range from 9.5 to 11 and salt concentrations up to saturation. More than 100 strains of this genus have been isolated from various soda lakes all over the world, but only ten species have been effectively described yet. Therefore, the assignment of the remaining strains to either existing or novel species is important and will further elucidate their genomic diversity as well as give a better general understanding of this genus. Recently, the genomes of 76 Thioalkalivibrio strains were sequenced. On these, we applied different methods including (i) 16S rRNA gene sequence analysis, (ii) Multilocus Sequence Analysis (MLSA) based on eight housekeeping genes, (iii) Average Nucleotide Identity based on BLAST (ANIb) and MUMmer (ANIm), (iv) Tetranucleotide frequency correlation coefficients (TETRA), (v) digital DNA:DNA hybridization (dDDH) as well as (vi) nucleotide- and amino acid-based Genome BLAST Distance Phylogeny (GBDP) analyses. We detected a high genomic diversity by revealing 15 new “genomic” species and 16 new “genomic” subspecies in addition to the ten already described species. Phylogenetic and phylogenomic analyses showed that the genus is not monophyletic, because four strains were clearly separated from the other Thioalkalivibrio by type strains from other genera. Therefore, it is recommended to classify the latter group as a novel genus. The biogeographic distribution of Thioalkalivibrio suggested that the different “genomic” species can be classified as candidate disjunct or candidate endemic species. This study is a detailed genome-based classification and identification of members within the genus Thioalkalivibrio. However, future phenotypical and chemotaxonomical studies will be needed for a full species description of this genus. PMID:28282461

  5. Genomic diversity within the haloalkaliphilic genus Thioalkalivibrio.

    Science.gov (United States)

    Ahn, Anne-Catherine; Meier-Kolthoff, Jan P; Overmars, Lex; Richter, Michael; Woyke, Tanja; Sorokin, Dimitry Y; Muyzer, Gerard

    2017-01-01

    Thioalkalivibrio is a genus of obligate chemolithoautotrophic haloalkaliphilic sulfur-oxidizing bacteria. Their habitat are soda lakes which are dual extreme environments with a pH range from 9.5 to 11 and salt concentrations up to saturation. More than 100 strains of this genus have been isolated from various soda lakes all over the world, but only ten species have been effectively described yet. Therefore, the assignment of the remaining strains to either existing or novel species is important and will further elucidate their genomic diversity as well as give a better general understanding of this genus. Recently, the genomes of 76 Thioalkalivibrio strains were sequenced. On these, we applied different methods including (i) 16S rRNA gene sequence analysis, (ii) Multilocus Sequence Analysis (MLSA) based on eight housekeeping genes, (iii) Average Nucleotide Identity based on BLAST (ANIb) and MUMmer (ANIm), (iv) Tetranucleotide frequency correlation coefficients (TETRA), (v) digital DNA:DNA hybridization (dDDH) as well as (vi) nucleotide- and amino acid-based Genome BLAST Distance Phylogeny (GBDP) analyses. We detected a high genomic diversity by revealing 15 new "genomic" species and 16 new "genomic" subspecies in addition to the ten already described species. Phylogenetic and phylogenomic analyses showed that the genus is not monophyletic, because four strains were clearly separated from the other Thioalkalivibrio by type strains from other genera. Therefore, it is recommended to classify the latter group as a novel genus. The biogeographic distribution of Thioalkalivibrio suggested that the different "genomic" species can be classified as candidate disjunct or candidate endemic species. This study is a detailed genome-based classification and identification of members within the genus Thioalkalivibrio. However, future phenotypical and chemotaxonomical studies will be needed for a full species description of this genus.

  6. The genus Isodon (Schrad. ex Benth. Spach in Africa and a new genus Rabdosiella Codd (Lamiaceae

    Directory of Open Access Journals (Sweden)

    L. E. Codd

    1984-12-01

    Full Text Available The typification of the genus Isodon (Schrad. ex Benth. Spach and its occurrence in Africa are discussed; an allied genus Rabdosiella Codd is described and the combinations R. calycina (Benth. Codd and R. ternifolia (D.Don Codd (the latter an Indian species are effected.

  7. The genus Isodon (Schrad. ex Benth. Spach in Africa and a new genus Rabdosiella Codd (Lamiaceae

    Directory of Open Access Journals (Sweden)

    L. E. Codd

    1984-12-01

    Full Text Available The typification of the genus Isodon (Schrad. ex Benth. Spach and its occurrence in Africa are discussed; an allied genus Rabdosiella Codd is described and the combinations R. calycina (Benth. Codd and R. ternifolia (D.Don Codd (the latter an Indian species are effected.

  8. The genus Hymenocrater: a comprehensive review.

    Science.gov (United States)

    Morteza-Semnani, Katayoun; Ahadi, Hamideh; Hashemi, Zahra

    2016-12-01

    The genus Hymenocrater Fisch. et Mey. (Lamiaceae) contains over 21 species in the world. Some species have been used in folk medicine around the world. The present review comprises the ethnopharmacological, phytochemical and therapeutic potential of various species of Hymenocrater. This review brings together most of the available scientific research regarding the genus Hymenocrater. Through this review, the authors hope to attract the attention of natural product researchers throughout the world to focus on the unexplored potential of Hymenocrater species. This review has been compiled using references from major databases such as Chemical Abstracts, Medicinal and Aromatic Plants Abstracts, ScienceDirect, SciFinder, Google Scholar, Scopus, PubMed, Springer Link and books, without limiting the dates of publication. General web searches were also carried out using Google and Yahoo search engines by applying some related search terms (e.g., Hymenocrater spp., phytochemical, pharmacological, extract, essential oil and traditional uses). The articles related to agriculture, ecology, and synthetic works and those using languages other than English or Persian have been excluded. The genus Hymenocrater contains essential oil. Flavonoids, phenolic acids and terpenoids are important constituents of this genus. The pharmacological studies confirmed that the species of the genus Hymenocrater showed antimicrobial, antiparasitic, antioxidant, anticancer and antidiabetic activities. This review discusses the current knowledge of Hymenocrater species that review therapeutic potential, especially their effects on the cancer cells and gaps offering opportunities for future research.

  9. Identification and nomenclature of the genus Penicillium.

    Science.gov (United States)

    Visagie, C M; Houbraken, J; Frisvad, J C; Hong, S-B; Klaassen, C H W; Perrone, G; Seifert, K A; Varga, J; Yaguchi, T; Samson, R A

    2014-06-01

    Penicillium is a diverse genus occurring worldwide and its species play important roles as decomposers of organic materials and cause destructive rots in the food industry where they produce a wide range of mycotoxins. Other species are considered enzyme factories or are common indoor air allergens. Although DNA sequences are essential for robust identification of Penicillium species, there is currently no comprehensive, verified reference database for the genus. To coincide with the move to one fungus one name in the International Code of Nomenclature for algae, fungi and plants, the generic concept of Penicillium was re-defined to accommodate species from other genera, such as Chromocleista, Eladia, Eupenicillium, Torulomyces and Thysanophora, which together comprise a large monophyletic clade. As a result of this, and the many new species described in recent years, it was necessary to update the list of accepted species in Penicillium. The genus currently contains 354 accepted species, including new combinations for Aspergillus crystallinus, A. malodoratus and A. paradoxus, which belong to Penicillium section Paradoxa. To add to the taxonomic value of the list, we also provide information on each accepted species MycoBank number, living ex-type strains and provide GenBank accession numbers to ITS, β-tubulin, calmodulin and RPB2 sequences, thereby supplying a verified set of sequences for each species of the genus. In addition to the nomenclatural list, we recommend a standard working method for species descriptions and identifications to be adopted by laboratories working on this genus.

  10. A Genus Oblivious Approach to Cross Parameterization

    Energy Technology Data Exchange (ETDEWEB)

    Bennett, J C; Pascucci, V; Joy, K I

    2008-06-16

    In this paper we present a robust approach to construct a map between two triangulated meshes, M and M{prime} of arbitrary and possibly unequal genus. We introduce a novel initial alignment scheme that allows the user to identify 'landmark tunnels' and/or a 'constrained silhouette' in addition to the standard landmark vertices. To describe the evolution of non-landmark tunnels we automatically derive a continuous deformation from M to M{prime} using a variational implicit approach. Overall, we achieve a cross parameterization scheme that is provably robust in the sense that it can map M to M{prime} without constraints on their relative genus. We provide a number of examples to demonstrate the practical effectiveness of our scheme between meshes of different genus and shape.

  11. Revision of monotypic genus Llavea (Cryptogrammoideae: Pteridaceae

    Directory of Open Access Journals (Sweden)

    Mónica Palacios-Rios

    2016-12-01

    Full Text Available Llavea Lag. is a genus of Cryptogrammoideae (Pteridaceae, whose only species is distributed from southern United States and Mexico to Guatemala and Costa Rica, although it lives mainly in Mesoamerica, inhabiting preferably calcicolous habitats associated with forests and mountains. The genus is easily recognized by the presence of fertile leaves hemi-dimorphic, with the fertile apical portion with longer and narrower segments than the sterile ones, with strongly revolute margin, and rhizome scales bicolorous, shiny, and black. This paper presents a revision of the genus, nomenclatural issues are resolved, and and palynological morphological diversity are reviewed, as well as its distribution, phenology, ecology, and applications, based on field and herbarium specimens studies. In addition, two names related to Llavea, Allosorus karwinskii Kunze and Ceratodactylis osmundioides J. Sm., were lectotypified.

  12. The genus Craterium (Myxomycetes in Poland

    Directory of Open Access Journals (Sweden)

    Wanda Stojanowska

    2014-08-01

    Full Text Available The paper presents an extended list of species of the genus Craterium, hitherto found in Poland.In the monograph on Polish slime moulds Krzemieniewska (1960 3 species and 1 variety of that genus were mentioned. Lately, the following two new species have been recorded: Craterium concinnum Rex. and C. brunneum Nann.-Bremek. Craterium muscorum Ing, reported earlier under the name of Badhamia rubiginosa (Chevall Rostaf. is also included in the present paper. All together, with Cratoium aureum (Schumach. Rostaf. rarely occurring in Poland, and widespread C. minutum (Leers Fr., C. leucocephalum (Pers. Ditmar with its variety scyphoides (Cooke et Balf. G. Lister, the number of taxa of the genus Craterium in Poland increased up to 7.

  13. The genus curve of the Abell clusters

    Science.gov (United States)

    Rhoads, James E.; Gott, J. Richard, III; Postman, Marc

    1994-01-01

    We study the topology of large-scale structure through a genus curve measurement of the recent Abell catalog redshift survey of Postman, Huchra, and Geller (1992). The structure is found to be spongelike near median density and to exhibit isolated superclusters and voids at high and low densities, respectively. The genus curve shows a slight shift toward 'meatball' topology, but remains consistent with the hypothesis of Gaussian random phase initial conditions. The amplitude of the genus curve corresponds to a power-law spectrum with index n = 0.21(sub -0.47 sup +0.43) on scales of 48/h Mpc or to a cold dark matter power spectrum with omega h = 0.36(sub -0.17 sup +0.46).

  14. The genus Gymnospermium (Berberidaceae) in the Balkans

    DEFF Research Database (Denmark)

    Tan, Kit; Shuka, Lulezim; Siljak-Yakovlev, Sonja

    2011-01-01

    A revision of the genus Gymnospermium (Berberidaceae) in the Balkan Peninsula is carried out. Three species are recognised. Gymnospermium maloi is described as a new species from Mt. Picari in Gjirokastra district, southern Albania. It is compared with the closely related G. scipetarum which has...... has been reported for other members of the genus. The nuclear DNA content (2C-value) of all three species was determined. The genome size of G. maloi is 29.44 (± 0.47) pg, for G. scipetarum (chromosome number still unknown) 29.55 (± 1.35) pg, and for G. peloponnesiacum (2n = 2x = 16) 31.93 (± 2.38) pg....... These values are the first genome size measurements for the genus. All three species are mapped and fully illustrated. A key to the European species is also presented....

  15. Slope equalities for genus 5 surface fibrations

    CERN Document Server

    Tenni, Elisa

    2010-01-01

    K. Konno proved a slope equality for fibred surfaces with fibres of odd genus and general fibre of maximal gonality. More precisely he found a relation between the invariants of the fibration and certain weights of special fibres (called the Horikawa numbers). We give an alternative and more geometric proof in the case of a genus 5 fibration, under generality assumptions. In our setting we are able to prove that the fibre with positive Horikawa numbers are precisely the trigonal ones, we compute their weights explicitly and thus we exhibit explicit examples of regular surfaces with assigned invariants and Horikawa numbers.

  16. Systematics of the genus Daubenya (Hyacinthaceae: Massonieae

    Directory of Open Access Journals (Sweden)

    J. C. Manning

    2002-12-01

    Full Text Available Daubenya Lindl. was until recently thought to comprise the single species D. aurea Lindl. but is now considered to include the monotypic genera Androsiphon Schltr. and Amphisiphon W.F.Barker. as well as the species previously referred to the genus Neobakeria Schltr. Eight species are now recognized in the genus, including the new combinations Daubenya comata (Burch, ex Baker J.C.Manning & A.M.van der Merwe and D. zeyheri (Kunth J.C.Manning & A.M.van der Merwe. Each species is fully described and illustrated in black-and-white and in colour. A key to the species, and distribution maps are provided.

  17. Exponentially many maximum genus embeddings and genus embeddings for complete graphs

    Institute of Scientific and Technical Information of China (English)

    REN Han; BAI Yun

    2008-01-01

    There are many results on the maximum genus,among which most are written for the existence of values of such embeddings,and few attention has been paid to the estimation of such embeddings and their applications.In this paper we study the number of maximum genus embeddings for a graph and find an exponential lower bound for such numbers.Our results show that in general case,a simple connected graph has exponentially many distinct maximum genus embeddings.In particular,a connected cubie graph G of order n always has at least (√2)m+n+α/2 distinct maximum genus embeddings,where α and m denote,respectively,the number of inner vertices and odd compo-nents of an optimal tree T.What surprise us most is that such two extremal embeddings (i.e.,the maximum genus embeddings and the genus embeddings) are sometimes closely related with each other.In fact,as applications,we show that for a sufficient large natural number n,there are at least C2n/4 many genus embeddings for complete graph Kn with n=4,7,10 (mod12),where C is a constance depending on the Value of n of residue 12.These results improve the bounds obtained by Korzhik and Voss and the methods used here are much simpler and straight.

  18. Reproductive traits and population structure of Astyanax aeneus (Characiformes: Characidae from a subtropical river in Mexico Rasgos reproductivos y estructura de la población de Astyanax aeneus (Characiformes: Characidae de un río subtropical en México

    Directory of Open Access Journals (Sweden)

    Patricia Trujillo-Jiménez

    2013-06-01

    Full Text Available Champotón River is an unknown area within the Mesoamerican hotspot in Southestern México. Reproductive traits and population structure of Astyanax aeneus were analyzed along an environmental gradient of the upper, middle and lower sections of the river, where diverse environmental factors were recorded. For this, nets were cast for 1h at each site and A. aeneus were collected from all sections with sweep nets (5 and 10m long by 5m deep, 0.03m mesh size and a casting net (0.05m mesh size. At each study site and campaign, a total of 80 specimens (in average were collected and were fixed in 10% formaldehyde for further analysis. Population structure by size was analyzed for each study site, based on the relative frequencies by standard length classes. The length-weight relationship was determined, and the identification of gonadal developmental stages, reproductive period, size at first sexual maturity, relative fecundity, sex ratio and somatic indexes (gonadosomatic, hepatosomatic and Fulton’s condition factor were also assessed. Seven size classes were found in the upper and middle sections, and nine downstream, with seasonal and spatial pattern in size-class frequency distribution. Size at first maturity was 45.7mm for females and 40.8mm for males. The maximum relative fecundity was recorded at the downstream site and was positively correlated with body weight and standard length. Sex ratio (1.8:1 males: females differed significantly from expected values (1:1. Gonadosomatic index scores indicated that the reproductive period of this species in the Champotón River was from April to July, during the warm and wet season. Hepatosomatic index was negatively correlated with the Gonadosomatic index, evidencing transfer of energy from the liver towards gamete production. This strategy enabled A. aeneus to maintain robustness during the study period with tiny changes in condition factor. A. aeneus in the Champotón River, as opposed to South

  19. Identification and nomenclature of the genus Penicillium

    DEFF Research Database (Denmark)

    Visagie, C.M.; Houbraken, J.; Frisvad, Jens Christian

    2014-01-01

    . Although DNA sequences are essential for robust identification of Penicillium species, there is currently no comprehensive, verified reference database for the genus. To coincide with the move to one fungus one name in the International Code of Nomenclature for algae, fungi and plants, the generic concept...

  20. The position of the genus Thomandersia Bail

    NARCIS (Netherlands)

    Bremekamp, C.E.B.

    1942-01-01

    Among the most aberrant types of pollen grains found in plants which have been referred to the family Acanthaceae, are those of the genera Meyenia N. ab E. and Thomandersia Baill. Although the pollen grains were described by LINDAU under different names, those of the first genus as cogwheel-shaped

  1. The genus Alocasia (Araceae) in Australasia

    NARCIS (Netherlands)

    Hay, A.; Wise, Rosemary

    1991-01-01

    The genus Alocasia (Araceae) is revised for Australasia. Thirteen species are recognised and keyed; eleven are endemic to and one is thought to be introduced to and escaped in Papuasia; A. brisbanensis (F.M. Bailey) Domin is endemic to Australia, and is redescribed; five are new to science. The

  2. Paramyristica, a new genus of Myristicaceae

    OpenAIRE

    Wilde, de, J.G.S.

    1994-01-01

    The new genus Paramyristica from New Guinea, based on Myristica sepicana Foreman, is described and discussed, and included in keys to the Asian genera of Myristicaceae. Detailed drawings of the androecia of Paramyristica sepicana and of Myristica hooglandii and M. hollrungii are presented for comparison.

  3. Endocomia, a new genus of Myristicaceae

    NARCIS (Netherlands)

    Wilde, de W.J.J.O.

    1984-01-01

    The new genus Endocomia, ranging from South China to New Guinea, is described, keyed out and discussed among the other four Southeast Asiatic genera of Myristicaceae, viz. Knema, Myristica, Gymnacranthera, and Horsfieldia. Endocomia was formerly included in Horsfieldia under the name H. macrocoma, a

  4. Revision of the genus Gymnacranthera (Myristicaceae)

    NARCIS (Netherlands)

    Schouten, R.T.A.

    1986-01-01

    In Gymnacranthera, a small genus of Southeast Asian Myristicaceae, at present 7 species have been accepted, one (G. forbesii) with 2 and another ( G. farquhariana) with 4 varieties. One species, G. canarica, occurs in S. India, the remainder of the species is distributed in the area from S. Thailand

  5. Paramyristica, a new genus of Myristicaceae

    NARCIS (Netherlands)

    Wilde, de W.J.J.O.

    1994-01-01

    The new genus Paramyristica from New Guinea, based on Myristica sepicana Foreman, is described and discussed, and included in keys to the Asian genera of Myristicaceae. Detailed drawings of the androecia of Paramyristica sepicana and of Myristica hooglandii and M. hollrungii are presented for compar

  6. The composite genus Blumea, a taxonomic revision

    NARCIS (Netherlands)

    Randeria, Aban J.

    1960-01-01

    My first acquaintance with the genus Blumea was made in December of 1949. On one of my taxonomy field trips then, and many more subsequently, I encountered these weedy, yellow-flowered composites. Perhaps what most helped to attract my attention was their relative abundance and their characteristic

  7. The genus Malassezia and human disease

    Directory of Open Access Journals (Sweden)

    Inamadar A

    2003-07-01

    Full Text Available Sabouraud's Pityrosporum is now recognized as Malassezia. With taxonomic revision of the genus, newer species have been included. The role of this member of the normal human skin flora in different cutaneous and systemic disorders is becoming clearer. The immunological responses it induces in the human body are conflicting and their relevance to clinical features is yet to be explored.

  8. A conspectus of the genus Bhesa (Celastraceae)

    NARCIS (Netherlands)

    Hou, Ding

    1958-01-01

    In his Numerical List Wallich inserted four specific epithets in the genus Kurrimia, viz 4334 K. pulcherrima Wall., 4335 K. calophylla Wall., 4336 K. paniculata Wall., and later 7200 K.? macrophylla Wall. The latter one was provided with a question mark; it was a new combination for Itea macrophylla

  9. The genus Lophopyxis Hook. f. (Lophopyxidaceae)

    NARCIS (Netherlands)

    Sleumer, H.

    1968-01-01

    When revising the Icacinaceae from SE. Asia and Malesia recently, my interest was drawn again to the genus Lophopyxis Hook. f. Designated by its author (1887) tentatively as a member of the Euphorbiaceae, it was rejected from this family by Pax as early as 1890. Engler (1893) transferred Lophopyxis

  10. The genus Lolium; taxonomy and genetic resources.

    NARCIS (Netherlands)

    Loos, B.P.

    1994-01-01

    Several aspects of variation within the genus Lolium, and more in detail within Lolium perenne (perennial ryegrass) have been highlighted. As the results are extensively discussed in each chapter, the general discussion is focused on two aspects of the research.SpeciationIt is clear that the

  11. The genus Echinostelium (Myxomycetes in Lithuania

    Directory of Open Access Journals (Sweden)

    Gražina Adamonytė

    2013-12-01

    Full Text Available Seven species of the genus – Echinostelium apitectum, E. arboreum, E. brooksii, E. colliculosum, E. corynophorum, E. aff. elachiston, E. minutum – are reported from Lithuania. Their morphological peculiarities are discussed; a key to the species, pictures and distribution maps are given.

  12. The genus Alfonsiella Waterston (Hymenoptera, Chalcidoidea, Agaonidae)

    NARCIS (Netherlands)

    Wiebes, J.T.

    1972-01-01

    This paper is a tribute to Prof. Dr. L. D. Brongersma, in remembrance of the years I served as his deputy in the Rijksmuseum van Natuurlijke Historie. The genus Alfonsiella was described by Waterston (1920) for A. fimbriata, a series of females of which were collected at Dar es Salaam, Tanganyika. I

  13. Phylogeny and taxonomy of the genus Gliocladiopsis

    NARCIS (Netherlands)

    Lombard, L.; Crous, P.W.

    2012-01-01

    Using a global set of isolates and a phylogenetic approach employing DNA sequence data from five genes (ß-tubulin, histone H3, internal transcribed spacer region, 28S large subunit region and translation elongation factor 1-a), the taxonomic status of the genus Gliocladiopsis (Glionectria)

  14. Phylogeny and taxonomy of the genus Gliocladiopsis

    NARCIS (Netherlands)

    Lombard, L.; Crous, P.W.

    2012-01-01

    Using a global set of isolates and a phylogenetic approach employing DNA sequence data from five genes (β-tubulin, histone H3, internal transcribed spacer region, 28S large subunit region and translation elongation factor 1-α), the taxonomic status of the genus Gliocladiopsis (Glionectria)

  15. A revision of the genus Podococcus

    NARCIS (Netherlands)

    Valkenburg, van J.L.C.H.; Sunderland, T.

    2008-01-01

    A taxonomic revision of the palm genus Podococcus (Arecaceae) is presented. Two species are recognised: P. barteri, a species relatively widespread in a coastal band from Nigeria to the D. R. Congo and P. acaulis, a species previously considered conspecific to P. barteri, almost exclusively confined

  16. The genus Alocasia (Araceae) in Australasia

    NARCIS (Netherlands)

    Hay, A.; Wise, Rosemary

    1991-01-01

    The genus Alocasia (Araceae) is revised for Australasia. Thirteen species are recognised and keyed; eleven are endemic to and one is thought to be introduced to and escaped in Papuasia; A. brisbanensis (F.M. Bailey) Domin is endemic to Australia, and is redescribed; five are new to science. The genu

  17. Palynology of the Genus Stachytarpheta Vahl. (Verbenaceae

    Directory of Open Access Journals (Sweden)

    Olubukola ADEDEJI

    2010-12-01

    Full Text Available The exine morphology of pollen grains of Stachytarpheta indica (Linn. Vahl, Stachytarpheta cayennensis (Rich. Vahl and Stachytarpheta angustifolia (Mill. Vahl is reported. This study was carried out with a light microscope. Pollen grains from fresh anthers were collected and aceolysed. Statistical analysis used to analyse the data collected include cluster analysis, correlation analysis, similarity and distance indices. The pollen grains are spheroidal to oblate to sub-oblate in shape. They are aperturate, both colpate and porate. Tricolpate types occur most frequently, acolpate, monocolpate, bicolpate and tetracolpate types less frequently. The multicolpate and multiporate attributes in all the species indicate that the genus is not primitive in evolutionary history and this species probably, evolved around in the same time. According to the size, the pollen grains of the genus falls into groups permagna (pollen diameter 100-200 ?m and giganta (pollen diameter greater than 200 ?m. S. cayennensis and S. anguistifolia belong to group permagna and S. indica only in the group giganta. This separates S. indica from the other two species. The large pollen grain size in the genus clearly supports the fact that the flowers in the genus are more insect-and-bird pollinated than wind pollinated. The similarity and distance indices of the species showed that S. cayennensis and S. angustifolia are the closest. S. indica is closer to S. angustifolia but farther from S. cayennensis.

  18. Note on the Genus Microsicydium Bleeker

    NARCIS (Netherlands)

    Koumans, F.P.

    1929-01-01

    This genus was established by Dr. P. BLEEKER in 1874 1) for fishes belonging to the phalanx Sicydiini having the caracteristics: „Dentes intermaxillares stipitati apice clavati obtusi, inframaxillares serie interna parvi aequales, serie externa aciculares. Maxilla inferior cirris nullis. Squamae cap

  19. Phylogeny of the plant genus Pachypodium (Apocynaceae

    Directory of Open Access Journals (Sweden)

    Dylan O. Burge

    2013-04-01

    Full Text Available Background. The genus Pachypodium contains 21 species of succulent, generally spinescent shrubs and trees found in southern Africa and Madagascar. Pachypodium has diversified mostly into arid and semi-arid habitats of Madagascar, and has been cited as an example of a plant group that links the highly diverse arid-adapted floras of Africa and Madagascar. However, a lack of knowledge about phylogenetic relationships within the genus has prevented testing of this and other hypotheses about the group. Methodology/Principal Findings. We use DNA sequence data from the nuclear ribosomal ITS and chloroplast trnL-F region for all 21 Pachypodium species to reconstruct evolutionary relationships within the genus. We compare phylogenetic results to previous taxonomic classifications and geography. Results support three infrageneric taxa from the most recent classification of Pachypodium, and suggest that a group of African species (P. namaquanum, P. succulentum and P. bispinosum may deserve taxonomic recognition as an infrageneric taxon. However, our results do not resolve relationships among major African and Malagasy lineages of the genus. Conclusions/Significance. We present the first molecular phylogenetic analysis of Pachypodium. Our work has revealed five distinct lineages, most of which correspond to groups recognized in past taxonomic classifications. Our work also suggests that there is a complex biogeographic relationship between Pachypodium of Africa and Madagascar.

  20. A new genus of Blacinae (Hymenoptera: Braconidae)

    Science.gov (United States)

    Lester P. Gibson

    1977-01-01

    A new genus, Canalicephalus, of the subfamily Blacinae is described along with 4 new species, C. orientalis from Borneo, C. novus from New Guinea, and C. bakeri and C. mindanao, both from the Philippines. Keys are included to separate these 2 genera and the 4...

  1. The genus Kochia (Chenopodiaceae) in North America

    Science.gov (United States)

    Ge-Lin Chu; Stewart Sanderson

    2008-01-01

    The genus Kochia and Bassia with which it has been combined, of Chenopodiaceae tribe Camphorosmeae, were at one time considered to include plants native to Eurasia, Australia, and North America, and included species of both C3 and C4 photosynthetic types. This aggregate has been reduced in size by removal of a large group of C3 Australian genera and species. Because of...

  2. Bark beetles in the genus Dendroctonus

    Science.gov (United States)

    Barbara J. Bentz

    2008-01-01

    The genus Dendroctonus (Coleoptera: Curculionidae, Scolytinae), originally described by Erichson in 1836, currently includes 19 species that are widely distributed. Seventeen species occur between Arctic North America and northwestern Nicaragua, and an additional two species are in northern Europe and Asia. Dendroctonus species attack and infest conifer hosts (Pinaceae...

  3. Chemotaxonomy of the genus Nuxia (Buddlejaceae)

    DEFF Research Database (Denmark)

    Jensen, Søren Rosendal

    1999-01-01

    An investigation of two species of Nuxia (Buddlejaceae) showed that this genus is characterised by the presence of the eight-carbon iridoid glucoside unedoside and/or its derivatives. From N. floribunda was isolated unedoside, nuxioside (6-O-a-L-rhamnopyranosyl-unedoside) and 2''-acetyl-3...

  4. Genome Evolution in the Genus Sorghum (Poaceae)

    OpenAIRE

    Price, H. James; Dillon, Sally L.; HODNETT, GEORGE; Rooney, William L.; Ross, Larry; Johnston, J Spencer

    2005-01-01

    • Background and Aims The roles of variation in DNA content in plant evolution and adaptation remain a major biological enigma. Chromosome number and 2C DNA content were determined for 21 of the 25 species of the genus Sorghum and analysed from a phylogenetic perspective.

  5. Interspecific hybridization in the genus Tulipa L.

    NARCIS (Netherlands)

    Creij, van M.G.M.

    1997-01-01

    The genus Tulipa L. comprises about 55 species. The tulip species are classified in two subgenera, Tulipa and Eriostemones, which are subdivided into five and three sections respectively. Commercial tulips are mainly cultivars of T. gesneriana L . and of Darwin hybrids, the latter of which are obtai

  6. Sarawakodendron, a new genus of Celastraceae

    NARCIS (Netherlands)

    Hou, Ding

    1967-01-01

    During my trip to Malaysia in 1966, sponsored by the Netherlands Foundation for the Advancement of Tropical Research (WOTRO), for doing field work on Anacardiaceae, a new tree genus was found in Sarawak belonging to the family Celastraceae which I have revised for the Flora Malesiana series I, volum

  7. The genus Lolium : taxonomy and genetic resources

    NARCIS (Netherlands)

    Loos, B.P.

    1994-01-01

    Several aspects of variation within the genus Lolium, and more in detail within Lolium perenne (perennial ryegrass) have been highlighted. As the results are extensively discussed in each chapter, the general discussion is focused on two aspects of

  8. Farrowia, a new genus in the Chaetomiaceae

    NARCIS (Netherlands)

    Hawksworth, D.L.

    1975-01-01

    The new genus Farrowia D. Hawksw. is described to accommodate Chaetomium longicolleum Krzem. & Badura and C. longirostre (Farrow) L. Ames, species formerly incorrectly referred to Chaetoceratostoma Turc. & Maffei. These two species are united under the name F. longicollea (Krzem. & Badura) D. Hawksw

  9. Taxonomic novelties in the genus Campylospermum (Ochnaceae)

    NARCIS (Netherlands)

    Bissiengou, P.; Chatrou, L.W.; Wieringa, J.J.; Sosef, M.S.M.

    2013-01-01

    Four new species, one with two subspecies, of the genus Campylospermum are described, all endemic or sub-endemic to Gabon. These are C. auriculatum, C. gabonensis, C. gabonensis subsp. australis, C. glaucifolium and C. occidentalis. Distribution maps and scans of the holotypes are provided as well a

  10. Nomenclatural changes in the genus Bremeria (Rubiaceae)

    NARCIS (Netherlands)

    Davis, A.P.; Razafimandimbison, S.G.; Andriambololonera, S.

    2011-01-01

    Five new combinations are made in the genus Bremeria: B. arachnocarpa, B. eriantha, B. scabrella, B. landia var. holosericea, and B. landia var. stadmanii. Bremeria gerrardii is conspecific with Gaertnera phanerophlebia, and thus excluded from Bremeria. Lectotypes are designated for Mussaenda erecti

  11. Fayochytriomyces, a new genus within Chytridiales.

    Science.gov (United States)

    Davis, William J; Letcher, Peter M; Longcore, Joyce E; Powell, Martha J

    2015-01-01

    Chytriomyces is a complex genus in Chytridiales. The morphological concept of the genus expanded as new taxa were added, and studies of zoospore ultrastructure and molecular phylogenies have revealed the genus to be polyphyletic. One problematic taxon is C. spinosus Fay, a distinctive species characterized by whorls of spines on the zoosporangium and a large accumulation of vesicle material beneath the operculum. With light-, scanning-electron and transmission-electron microscopy, we examined a culture (WJD186) isolated from a muck sample collected from a temporary forest pond. We also analyzed the D1-D2 variable domains of the nuc 28S rDNA (28S) sequences to confirm the phylogenetic placement of the species relative to the type of Chytriomyces, C. hyalinus Karling. The morphology of culture WJD186 is consistent with features Fay described for C. spinosus, and the zoospore ultrastructure is consistent with the Group I-type zoospore characters of Chytriomycetaceae (Chytridiales). In our molecular phylogeny C. spinosus does not group with the type of Chytriomyces. Consequently, we erect a new genus in Chytriomycetaceae and present the new combination Fayochytriomyces spinosus. © 2015 by The Mycological Society of America.

  12. NSR superstring measures in genus 5

    NARCIS (Netherlands)

    Dunin-Barkovskiy, P.; Sleptsov, A.; Stern, A.

    2013-01-01

    Currently there are two proposed ansätze for NSR superstring measures: the Grushevsky ansatz and the OPSMY ansatz, which for genera g⩽4g⩽4 are known to coincide. However, neither the Grushevsky nor the OPSMY ansatz leads to a vanishing two-point function in genus four, which can be constructed from

  13. The Mesozoic megafossil genus Linguifolium Arber 1917

    Directory of Open Access Journals (Sweden)

    Pattemore Gary A.

    2015-12-01

    Full Text Available The plant megafossil genus Linguifolium Arber 1917 is chiefly known from the Middle and Upper Triassic of Gondwana. The range of Linguifolium extended beyond Gondwana by the Late Triassic, persisting there through the earliest Jurassic (Hettangian. The parent plants probably grew in a well-watered, canopied environment.

  14. The position of the genus Thomandersia Bail

    NARCIS (Netherlands)

    Bremekamp, C.E.B.

    1942-01-01

    Among the most aberrant types of pollen grains found in plants which have been referred to the family Acanthaceae, are those of the genera Meyenia N. ab E. and Thomandersia Baill. Although the pollen grains were described by LINDAU under different names, those of the first genus as cogwheel-shaped a

  15. Feeding and morphological analysis of the digestive tract of four species of fish (Astyanax altiparanae, Parauchenipterus galeatus, Serrasalmus marginatus and Hoplias aff. malabaricus from the upper Paraná River floodplain, Brazil

    Directory of Open Access Journals (Sweden)

    D. Peretti

    Full Text Available The present study is inspired by the great wealth of species exhibited by the ichthiofauna. Not only concepts and techniques of ecology deserve attention, but also knowledge in other biological areas, such as zoology and anatomy, are necessary. The intention of the present work is to discover the morphology of fish through the study of the digestive tract morphology, associating it to diet data, in order to better understand the biology of four fish species of the upper Paraná River floodplain. The samples were collected quarterly in the year 2000 with gillnets of different meshes. The stomach content was analyzed under a stereoscopic microscope and the frequencies of occurrence (FO and volumetric (FV and the alimentary index (IAi were calculated. Various morphologic characteristics were analyzed and schematized using a light chamber. The species were grouped into two trophic guilds - insectivores (Astyanax altiparanae and Parauchenipterus galeatus and piscivores (Serrasalmus marginatus and Hoplias aff. malabaricus. The first two, although consumers of insects, preyed on different alimentary groups, notably Hymenoptera in the case of A. altiparanae and Coleoptera in the case of P. galeatus. Serrasalmus marginatus and H. aff. malabaricus consumed mainly fishes. However, only pieces of prey were usually found in the stomach content of the first species, whereas whole fishes were found in the stomach content of the second. Astyanax altiparanae exhibited characteristics that allowed it to obtain food in several compartments of the water column. Similarly P. galeatus consumed food resources that were available in all aquatic compartments, although the abilities to capture, to manipulate and to absorb food differed, as shown by the importance of teeth plates and pharyngeal teeth. Serrasalmus marginatus and H. aff. malabaricus, although resembling each other in many aspects of the digestive tract morphology, differed in the strategies used to capture

  16. Mitogenomic analysis of the genus Panthera.

    Science.gov (United States)

    Wei, Lei; Wu, Xiaobing; Zhu, Lixin; Jiang, Zhigang

    2011-10-01

    The complete sequences of the mitochondrial DNA genomes of Panthera tigris, Panthera pardus, and Panthera uncia were determined using the polymerase chain reaction method. The lengths of the complete mitochondrial DNA sequences of the three species were 16990, 16964, and 16773 bp, respectively. Each of the three mitochondrial DNA genomes included 13 protein-coding genes, 22 tRNA, two rRNA, one O(L)R, and one control region. The structures of the genomes were highly similar to those of Felis catus, Acinonyx jubatus, and Neofelis nebulosa. The phylogenies of the genus Panthera were inferred from two combined mitochondrial sequence data sets and the complete mitochondrial genome sequences, by MP (maximum parsimony), ML (maximum likelihood), and Bayesian analysis. The results showed that Panthera was composed of Panthera leo, P. uncia, P. pardus, Panthera onca, P. tigris, and N. nebulosa, which was included as the most basal member. The phylogeny within Panthera genus was N. nebulosa (P. tigris (P. onca (P. pardus, (P. leo, P. uncia)))). The divergence times for Panthera genus were estimated based on the ML branch lengths and four well-established calibration points. The results showed that at about 11.3 MYA, the Panthera genus separated from other felid species and then evolved into the several species of the genus. In detail, N. nebulosa was estimated to be founded about 8.66 MYA, P. tigris about 6.55 MYA, P. uncia about 4.63 MYA, and P. pardus about 4.35 MYA. All these estimated times were older than those estimated from the fossil records. The divergence event, evolutionary process, speciation, and distribution pattern of P. uncia, a species endemic to the central Asia with core habitats on the Qinghai-Tibetan Plateau and surrounding highlands, mostly correlated with the geological tectonic events and intensive climate shifts that happened at 8, 3.6, 2.5, and 1.7 MYA on the plateau during the late Cenozoic period.

  17. Certhiasomus, a new genus of woodcreeper (Aves: Passeriformes: Dendrocolaptidae)

    Science.gov (United States)

    Derryberry, Elizabeth; Claramunt, Santiago; Chesser, R. Terry; Aleixo, Alexandre; Cracraft, Joel; Moyle, Robert G.; Brumfield, Robb T.

    2010-01-01

    Phylogenetic analysis of the family Dendrocolaptidae (Aves: Passeriformes) indicates that the two species traditionally placed in the genus Deconychura are not sister taxa. Certhiasomus, a new genus of woodcreeper, is described for one of these species, C. stictolaemus.

  18. An account of the fern genus Belvisia Mirbel (Polypodiaceae)

    NARCIS (Netherlands)

    Hovenkamp, P.H.; Franken, N.A.P.

    1993-01-01

    The genus Belvisia is revised. Two species are transferred from Lemmaphyllum to Belvisia, and two species are reduced to varieties. The genus now includes eight species, reaching from tropical Africa to China, Polynesia, and Australia.

  19. A preliminary survey of the genus Buchwaldoboletus (Boletales: Boletaceae)

    Science.gov (United States)

    Beatriz Ortiz-Santana; Ernst E. Both

    2011-01-01

    Buchwaldoboletus is a small genus of about a dozen species with a world-wide distribution. The boletes of this genus are non-mycorrhizal, saprophytic and lignicolous. A preliminary survey is provided and seven new combinations are proposed.

  20. A New Genus of Macropsinae (Hemiptera: Cicadellidae) From Madagascar.

    Science.gov (United States)

    Yang, Liyuan; Dietrich, C H; Zhang, Yalin

    2016-01-01

    Paragalboa acuta GEN & SP N: is described and illustrated from Madagascar. The new genus shows morphological affinities to the Macropsini genus Galboa Distant recorded from Seychelles. A checklist of all known genera of Macropsinae is provided.

  1. Genus Phyllanthus for chronic hepatitis B virus infection

    DEFF Research Database (Denmark)

    Liu, J; Lin, Haili; McIntosh, H

    2001-01-01

    To evaluate the efficacy and safety of genus Phyllanthus for chronic hepatitis B virus (HBV) infection we performed a systematic review of randomized clinical trials. Randomized trials comparing genus Phyllanthus vs. placebo, no intervention, general nonspecific treatment, other herbal medicine...

  2. Exponentially many maximum genus embeddings and genus embeddings for complete graphs

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    There are many results on the maximum genus, among which most are written for the existence of values of such embeddings, and few attention has been paid to the estimation of such embeddings and their applications. In this paper we study the number of maximum genus embeddings for a graph and find an exponential lower bound for such numbers. Our results show that in gen-eral case, a simple connected graph has exponentially many distinct maximum genus embeddings. In particular, a connected cubic graph G of order n always has at least 2~1/2m+n+ α2 distinct maximum genus embeddings, where α and m denote, respectively, the number of inner vertices and odd compo-nents of an optimal tree T . What surprise us most is that such two extremal embeddings (i.e., the maximum genus embeddings and the genus embeddings) are sometimes closely related with each other. In fact, as applications, we show that for a suffcient large natural number n, there are at least C2 n4 dmeapneyn dgienngu os ne mthbee vdadliuneg soffonrocf ormespidleutee 1g2r.a pThh eKsen rwesiuthlt sn i m≡p r4o,v 7e, 1th0e ( mbooudn1d2)s, owbthaeirnee dC b iys Ka ocroznhsikta anncde Voss and the methods used here are much simpler and straight.

  3. Taxonomy of the genus Passerina (Thymelaeaceae)

    OpenAIRE

    C. L. Bredenkamp; A. E. van Wyk

    2003-01-01

    Passerina L. is mainly a southern African genus, comprising 20 species and four subspecies. A few species occur along the Great Escarpment, two extend into Zimbabwe and Mozambique, but most are concentrated in the Cape Floristic Region. Palynological. macromorphological and anatomical evidence was used in the delimitation of the genus and its infrageneric taxa. A cladistic study supports Passerina as a monophyletic genus. A genus treatment, key to species and a full species treatment are give...

  4. Pseudasthenes, a new genus of ovenbird (Aves: Passeriformes: Furnariidae)

    Science.gov (United States)

    Derryberry, Elizabeth; Claramunt, Santiago; O'Quin, Kelly E.; Aleixo, Alexandre; Chesser, R. Terry; Remsen, J.V.; Brumfield, Robb T.

    2010-01-01

    Phylogenetic analysis of the family Furnariidae (Aves: Passeriformes) indicates that the genus Asthenes is polyphyletic, consisting of two groups that are not sister taxa. Pseudasthenes, a new genus of ovenbird, is described for one of these groups. The four species included in the new genus, formerly placed in Asthenes, are P. humicola, P. patagonica, P. steinbachi, and P. cactorum.

  5. Notes on the genus Digitaria, with descriptions of new species

    NARCIS (Netherlands)

    Henrard, J.Th.

    1934-01-01

    Some years ago I had the opportunity to study more extensively a very interesting group of grasses, belonging to what is now accepted as a distinct genus, the genus Digitaria, formerly belonging as a subgenus to the genus Panicum. As to living plants of this group I was familiar with two european sp

  6. Topological classification and enumeration of RNA structures by genus

    DEFF Research Database (Denmark)

    Andersen, Jørgen Ellegaard; Penner, Robert; Reidys, C. M.

    2013-01-01

    To an RNA pseudoknot structure is naturally associated a topological surface, which has its associated genus, and structures can thus be classified by the genus. Based on earlier work of Harer-Zagier, we compute the generating function for the number of those structures of fixed genus and minimum...

  7. Modular functors are determined by their genus zero data

    DEFF Research Database (Denmark)

    Andersen, Jørgen Ellegaard; Ueno, Kenji

    2012-01-01

    We prove in this paper that the genus zero data of a modular functor determines the modular functor. We do this by establishing that the S-matrix in genus one with one point labeled arbitrarily can be expressed in terms of the genus zero information and we give an explicit formula. We do not assu...

  8. The strong symmetric genus of the finite Coxeter groups

    OpenAIRE

    2004-01-01

    The strong symmetric genus of a finite group G is the smallest genus of a closed orientable topological surface on which G acts faithfully as a group of orientation preserving automorphisms. In this paper we complete the calculation of the strong symmetric genus for each finite Coxeter group excluding the group E8.

  9. A taxonomic revision of the genus Ixonanthes (Linaceae)

    NARCIS (Netherlands)

    Kool, R.

    1980-01-01

    In this revision 3 species are recognized for the Southeast Asian, mainly Malesian, genus Ixonanthes Jack (Linaceae). No new species are described, while 29 names have been placed into synonymy. It is proposed to unite the African genus Phyllocosmus Klotzsch with the American genus Ochthocosmus

  10. Redefinition of the genus Triophtydeus Thor, 1932 (Acari: Actinedida)

    NARCIS (Netherlands)

    André, H.M.

    1985-01-01

    The genus Triophtydeus Thor, 1932 is redefined from the study of the type-species, T. triophthalmus (Oudemans, 1929). The genus Metatriophtydeus André, 1980 is a junior synonym of Triophtydeus. Species belonging or likely to belong to the genus Triophtydeus are listed and generic and specific

  11. Remarks on the Lower Bounds for the Average Genus

    Institute of Scientific and Technical Information of China (English)

    Yi-chao Chen

    2011-01-01

    Let G be a graph of maximum degree at most four. By using the overlap matrix method which is introduced by B. Mohar, we show that the average genus of G is not less than 1/3 of its maximum genus, and the bound is best possible. Also, a new lower bound of average genus in terms of girth is derived.

  12. Genus Tinospora: Ethnopharmacology, Phytochemistry, and Pharmacology.

    Science.gov (United States)

    Chi, Sensen; She, Gaimei; Han, Dan; Wang, Weihua; Liu, Zhao; Liu, Bin

    2016-01-01

    The genus Tinospora includes 34 species, in which several herbs were used as traditional medicines by indigenous groups throughout the tropical and subtropical parts of Asia, Africa, and Australia. The extensive literature survey revealed Tinospora species to be a group of important medicinal plants used for the ethnomedical treatment of colds, headaches, pharyngitis, fever, diarrhea, oral ulcer, diabetes, digestive disorder, and rheumatoid arthritis. Indian ethnopharmacological data points to the therapeutic potential of the T. cordifolia for the treatment of diabetic conditions. While Tinospora species are confusing in individual ingredients and their mechanisms of action, the ethnopharmacological history of those plants indicated that they exhibit antidiabetic, antioxidation, antitumor, anti-inflammation, antimicrobial, antiosteoporosis, and immunostimulation activities. While the clinical applications in modern medicine are lacking convincing evidence and support, this review is aimed at summarizing the current knowledge of the traditional uses, phytochemistry, biological activities, and toxicities of the genus Tinospora to reveal its therapeutic potentials and gaps, offering opportunities for future researches.

  13. Phytochemistry of the genus Skimmia (Rutaceae).

    Science.gov (United States)

    Epifano, Francesco; Fiorito, Serena; Genovese, Salvatore; Granica, Sebastian; Vitalini, Sara; Zidorn, Christian

    2015-07-01

    The genus Skimmia is a rich source of interesting secondary metabolites, including 20 alkaloids derived from anthranilic acid, 45 coumarins, 21 limonoids, four cholestane derivatives, six pentacyclic triterpenes, six flavonoids, and two unusual fatty acid derivatives. Skimmia is employed in folk medicine e.g. against fever, inflammations, and rheumatism. Skimmia extracts, Skimmia essential oils and pure compounds isolated from Skimmia extracts have been experimentally shown to have various bioactivities such as antioxidant, anti-inflammatory, antimicrobial, and insecticidal. In this review we discuss the exact structures of compounds isolated from members of the genus Skimmia, bioactivities of Skimmia extracts and pure compounds derived from them, and systematic implications of the patterns of occurrence of these compounds. Moreover, research gaps and interesting avenues for future research are discussed briefly.

  14. Gene order phylogeny of the genus Prochlorococcus.

    Directory of Open Access Journals (Sweden)

    Haiwei Luo

    Full Text Available BACKGROUND: Using gene order as a phylogenetic character has the potential to resolve previously unresolved species relationships. This character was used to resolve the evolutionary history within the genus Prochlorococcus, a group of marine cyanobacteria. METHODOLOGY/PRINCIPAL FINDINGS: Orthologous gene sets and their genomic positions were identified from 12 species of Prochlorococcus and 1 outgroup species of Synechococcus. From this data, inversion and breakpoint distance-based phylogenetic trees were computed by GRAPPA and FastME. Statistical support of the resulting topology was obtained by application of a 50% jackknife resampling technique. The result was consistent and congruent with nucleotide sequence-based and gene-content based trees. Also, a previously unresolved clade was resolved, that of MIT9211 and SS120. CONCLUSIONS/SIGNIFICANCE: This is the first study to use gene order data to resolve a bacterial phylogeny at the genus level. It suggests that the technique is useful in resolving the Tree of Life.

  15. Monotone Hurwitz numbers in genus zero

    CERN Document Server

    Goulden, I P; Novak, Jonathan

    2012-01-01

    Hurwitz numbers count branched covers of the Riemann sphere with specified ramification data, or equivalently, transitive permutation factorizations in the symmetric group with specified cycle types. Monotone Hurwitz numbers count a restricted subset of the branched covers counted by the Hurwitz numbers, and have arisen in recent work on the the asymptotic expansion of the Harish-Chandra-Itzykson-Zuber integral. In this paper we begin a detailed study of monotone Hurwitz numbers. We prove two results that are reminiscent of those for classical Hurwitz numbers. The first is the monotone join-cut equation, a partial differential equation with initial conditions that characterizes the generating function for monotone Hurwitz numbers in arbitrary genus. The second is our main result, in which we give an explicit formula for monotone Hurwitz numbers in genus zero.

  16. Operators and higher genus mirror curves

    Science.gov (United States)

    Codesido, Santiago; Gu, Jie; Mariño, Marcos

    2017-02-01

    We perform further tests of the correspondence between spectral theory and topological strings, focusing on mirror curves of genus greater than one with nontrivial mass parameters. In particular, we analyze the geometry relevant to the SU(3) relativistic Toda lattice, and the resolved C{^3}/Z_6 orbifold. Furthermore, we give evidence that the correspondence holds for arbitrary values of the mass parameters, where the quantization problem leads to resonant states. We also explore the relation between this correspondence and cluster integrable systems.

  17. Operators and higher genus mirror curves

    CERN Document Server

    Codesido, Santiago; Marino, Marcos

    2016-01-01

    We perform further tests of the correspondence between spectral theory and topological strings, focusing on mirror curves of genus greater than one with nontrivial mass parameters. In particular, we analyze the geometry relevant to the SU(3) relativistic Toda lattice, and the resolved C^3/Z_6 orbifold. Furthermore, we give evidence that the correspondence holds for arbitrary values of the mass parameters, where the quantization problem leads to resonant states. We also explore the relation between this correspondence and cluster integrable systems.

  18. Genus Schistochila Dumort. (Schistochilaceae, Marchantiophyta in Thailand

    Directory of Open Access Journals (Sweden)

    Wanwisa Juengprayoon

    2015-08-01

    Full Text Available A review of the genus Schistochila Dumort. in Thailand is presented, based on the study of fresh and herbarium specimens. Five species are recognized, namely S. aligera (Nees & Blume J.B. Jack & Steph., S. blumei (Nees Trevis., S. nuda Horik., S. sciurea (Nees Schiffn., and S. yakushimensis Ohnishi & Deguchi. In addition, a key to species, descriptions and line drawings are provided, and notes on the ecology and geographical distribution of the species.

  19. Genomic characterization of the Yersinia genus

    Science.gov (United States)

    2010-01-01

    Background New DNA sequencing technologies have enabled detailed comparative genomic analyses of entire genera of bacterial pathogens. Prior to this study, three species of the enterobacterial genus Yersinia that cause invasive human diseases (Yersinia pestis, Yersinia pseudotuberculosis, and Yersinia enterocolitica) had been sequenced. However, there were no genomic data on the Yersinia species with more limited virulence potential, frequently found in soil and water environments. Results We used high-throughput sequencing-by-synthesis instruments to obtain 25- to 42-fold average redundancy, whole-genome shotgun data from the type strains of eight species: Y. aldovae, Y. bercovieri, Y. frederiksenii, Y. kristensenii, Y. intermedia, Y. mollaretii, Y. rohdei, and Y. ruckeri. The deepest branching species in the genus, Y. ruckeri, causative agent of red mouth disease in fish, has the smallest genome (3.7 Mb), although it shares the same core set of approximately 2,500 genes as the other members of the species, whose genomes range in size from 4.3 to 4.8 Mb. Yersinia genomes had a similar global partition of protein functions, as measured by the distribution of Cluster of Orthologous Groups families. Genome to genome variation in islands with genes encoding functions such as ureases, hydrogeneases and B-12 cofactor metabolite reactions may reflect adaptations to colonizing specific host habitats. Conclusions Rapid high-quality draft sequencing was used successfully to compare pathogenic and non-pathogenic members of the Yersinia genus. This work underscores the importance of the acquisition of horizontally transferred genes in the evolution of Y. pestis and points to virulence determinants that have been gained and lost on multiple occasions in the history of the genus. PMID:20047673

  20. The minimal genus problem in rational surfaces

    Institute of Scientific and Technical Information of China (English)

    ZHAO; Xu'an

    2006-01-01

    [1]Kronheimer P B,Mrowka T S.The genus of embedding surfaces in the projective plane.Math Res Lett,1994,1:797-808[2]Lawson T.The minimal genus problem.Expo Math,1997,15:385-431[3]Li B H.Representing nonnegative homology classes of CP2#n-CP2 by minimal genus smooth embedding.Trans Amer Soc,1999,352(9):4155-4169[4]Ruberman D.The minimal genus of an embedding surface of non-negative square in a rational surface.Turkish J Math,1996,20:129-133[5]Wall C T C.On the orthogonal groups of unimodular quadratic forms Ⅱ.Crelle Jour,1963,213:122-136[6]Gao H.Representing homology classes of almost definite 4-manifolds.Topology Appl,1993,52:109-120[7]Kikuchi K.Positive 2-spheres in 4-manifolds of signature (1,n).Pacific Jour Math,1993,160:245-258[8]Li B H,Li T J.Smooth minimal genera for small negative classes in CP2#n-CP2 with n ≤ 9.Topology Appl,2003,132(1):1-15[9]Friedman R,Morgan J.On the diffeomorphism types of certain algebraic surfaces.Journal of Differential Geometry,1988,27(3):371-398[10]Kac V G.Infinite-Dimensional Lie Algebras.3rd ed.Cambridge:Cambridge University Press,1990[11]Li T J,Liu A.Symplectic structure on ruled surfaces and generalized adjunction formula.Math Res Lett,1995,2:453-471

  1. Sexual Communication in the Drosophila Genus

    OpenAIRE

    Gwénaëlle Bontonou; Claude Wicker-Thomas

    2014-01-01

    In insects, sexual behavior depends on chemical and non-chemical cues that might play an important role in sexual isolation. In this review, we present current knowledge about sexual behavior in the Drosophila genus. We describe courtship and signals involved in sexual communication, with a special focus on sex pheromones. We examine the role of cuticular hydrocarbons as sex pheromones, their implication in sexual isolation, and their evolution. Finally, we discuss the roles of male cuticular...

  2. Concordance of Bing Doubles and Boundary Genus

    Science.gov (United States)

    Livingston, Charles; van Cott, Cornelia A.

    2011-11-01

    Cha and Kim proved that if a knot K is not algebraically slice, then no iterated Bing double of K is concordant to the unlink. We prove that if K has nontrivial signature $\\sigma$, then the n-iterated Bing double of K is not concordant to any boundary link with boundary surfaces of genus less than $2^{n-1}\\sigma$. The same result holds with $\\sigma$ replaced by $2\\tau$, twice the Ozsvath-Szabo knot concordance invariant.

  3. Phytochemical, ethnomedicinal uses and pharmacological profile of genus Pistacia.

    Science.gov (United States)

    Rauf, Abdur; Patel, Seema; Uddin, Ghias; Siddiqui, Bina S; Ahmad, Bashir; Muhammad, Naveed; Mabkhot, Yahia N; Hadda, Taibi Ben

    2017-02-01

    Pistacia genus belong to family Anacardiaceae and it is versatile in that its member species have food (P. vera), medicinal (P. lentiscus) and ornamental (P. chinensis) values. Various species of this genus have folkloric uses with credible mention in diverse pharmacopeia. As a trove of phenolic compounds, terpenoids, monoterpenes, flavonoids, alkaloids, saponins, fatty acids, and sterols, this genus has garnered pharmaceutical attention in recent times. With adequate clinical studies, this genus might be exploited for therapy of a multitude of inflammatory diseases, as promised by preliminary studies. In this regard, the ethnomedicinal, phytochemistry, biological potencies, risks, and scopes of Pistacia genus have been reviewed here.

  4. The genus Capsicum (Solanaceae in Africa

    Directory of Open Access Journals (Sweden)

    W. H. Eshbaugh

    1983-12-01

    Full Text Available The genus Capsicum (Solanaceae includes approximately 20 wild species and 4-5 domesticated taxa commonly referred to as ‘chilies’ or ‘peppers’. The pre-Colombian distribution of the genus was New World. The evolutionary history of the genus is now envisaged as including three distinct lines leading to the domesticated taxa. The route of Capsicum to the Old World is thought to have followed three different courses. First, explorers introduced it to Europe with secondary introduction into Africa via further exploratory expeditions; second, botanical gardens played a major role in introduction; and third, introduction followed the slave trade routes. Today, pepper production in Africa is of two types, vegetable and spice. Statistical profiles on production are difficult to interpret, but the data available indicate that Nigeria, Egypt, Tunisia and Ghana are the leading producers. Production is mainly a local phenomenon and large acreage is seldom devoted to the growing of peppers. The primary peppers in Africa are C.  annuum and C.  frutescens.

  5. Biodegradation of chlorpyrifos by bacterial genus Pseudomonas.

    Science.gov (United States)

    Gilani, Razia Alam; Rafique, Mazhar; Rehman, Abdul; Munis, Muhammad Farooq Hussain; Rehman, Shafiq Ur; Chaudhary, Hassan Javed

    2016-02-01

    Chlorpyrifos is an organophosphorus pesticide commonly used in agriculture. It is noxious to a variety of organisms that include living soil biota along with beneficial arthropods, fish, birds, humans, animals, and plants. Exposure to chlorpyrifos may cause detrimental effects as delayed seedling emergence, fruit deformities, and abnormal cell division. Contamination of chlorpyrifos has been found about 24 km from the site of its application. There are many physico-chemical and biological approaches to remove organophosphorus pesticides from the ecosystem, among them most promising is biodegradation. The 3,5,6-trichloro-2-pyridinol (TCP) and diethylthiophosphate (DETP) as primary products are made when chlorpyrifos is degraded by soil microorganisms which further break into nontoxic metabolites as CO(2), H(2)O, and NH(3). Pseudomonas is a diversified genus possessing a series of catabolic pathways and enzymes involved in pesticide degradation. Pseudomonas putida MAS-1 is reported to be more efficient in chlorpyrifos degradation by a rate of 90% in 24 h among Pseudomonas genus. The current review analyzed the comparative potential of bacterial species in Pseudomonas genus for degradation of chlorpyrifos thus, expressing an ecofriendly approach for the treatment of environmental contaminants like pesticides.

  6. The Pangenome of the genus Clostridium.

    Science.gov (United States)

    Udaondo, Zulema; Duque, Estrella; Ramos, Juan Luis

    2017-03-21

    We present the pangenome for the genus Clostridium sensu stricto, which was obtained using highly curated and annotated genomes from 16 species, some of these cause disease, while others are used for the production of added-value chemicals. Multilocus sequencing analysis revealed that species of this genus group into at least two clades that include non-pathogenic and pathogenic strains, suggesting that pathogenicity is dispersed across the phylogenetic tree. The core genome of the genus includes 546 protein families, which mainly comprise those involved in protein translation and DNA repair. The GS-GOGAT may represent the central pathway for generating organic nitrogen from inorganic nitrogen sources. Glycerol and glucose metabolism genes are well represented in the core genome together with a set of energy conservation systems. A metabolic network comprising proteins/enzymes, RNAs and metabolites, whose topological structure is a non-random and scale-free network with hierarchically structured modules was built. These modules shed light on the interactions between RNAs, proteins and metabolites, revealing biological features of transcription and translation, cell wall biosynthesis, C1 metabolism and N metabolism. Network analysis identified four nodes that function as hubs and bottlenecks, namely, coenzyme A, HPr kinases, S-adenosylmethionine and the ribonuclease P-protein, suggesting pivotal roles for them in Clostridium. This article is protected by copyright. All rights reserved.

  7. The genus Crataegus: chemical and pharmacological perspectives

    Directory of Open Access Journals (Sweden)

    Dinesh Kumar

    2012-10-01

    Full Text Available Traditional drugs have become a subject of world importance, with both medicinal and economical implications. A regular and widespread use of herbs throughout the world has increased serious concerns over their quality, safety and efficacy. Thus, a proper scientific evidence or assessment has become the criteria for acceptance of traditional health claims. Plants of the genus Crataegus, Rosaceae, are widely distributed and have long been used in folk medicine for the treatment of various ailments such as heart (cardiovascular disorders, central nervous system, immune system, eyes, reproductive system, liver, kidney etc. It also exhibits wide range of cytotoxic, gastroprotective, anti-inflammatory, anti-HIV and antimicrobial activities. Phytochemicals like oligomeric procyanidins, flavonoids, triterpenes, polysaccharides, catecholamines have been identified in the genus and many of these have been evaluated for biological activities. This review presents comprehensive information on the chemistry and pharmacology of the genus together with the traditional uses of many of its plants. In addition, this review discusses the clinical trials and regulatory status of various Crataegus plants along with the scope for future research in this aspect.

  8. Ethnopharmacology of the plants of genus Ajuga.

    Science.gov (United States)

    Israili, Zafar H; Lyoussi, Badiâa

    2009-10-01

    The plants of genus Ajuga are evergreen, clump-forming rhizomatous perennial or annual herbaceous flowering species, with Ajuga being one of the 266 genera of the family Lamiaceae. There are at least 301 species of the genus Ajuga with many variations. These plants, growing in Europe, Asia, Africa, Australia and North America, are used in gardens as ground cover or border for their foliage and beautiful flowers. Many of these plants have been used in traditional medicine as a remedy for fever, toothache, dysentery, malaria, high blood pressure, diabetes, gastrointestinal disorders, as anthelmintic, diuretic and antifungal, anti-inflammatory, and antimycobacterial agents. They are also used as insect growth inhibitor s. A large number of compounds have been isolated from the Ajuga plants, including phytoecdysteroids, neo-clerodane-diterpenes and diterpenoids, triterpenes, sterols, anthocyanidin-glucosides and iridoid glycosides, withanolides, flavonoids, triglycerides and essential oils. These compounds possess a broad spectrum of biological, pharmacological and medicinal properties, such as anabolic, analgesic, antibacterial, antiestrogenic, antifungal, anti-inflammatory, antihypertensive, antileukemic, antimalarial, antimycobacterial, antioxidant, antipyretic, cardiotonic, cytotoxic, hypoglycemic, and vasorelaxing activity, as well as antifeedant and insect growth-inhibitory properties. Thus, genus Ajuga has significant medicinal and economic importance.

  9. Standardized gene nomenclature for the Brassica genus

    Directory of Open Access Journals (Sweden)

    King Graham J

    2008-05-01

    Full Text Available Abstract The genus Brassica (Brassicaceae, Brassiceae is closely related to the model plant Arabidopsis, and includes several important crop plants. Against the background of ongoing genome sequencing, and in line with efforts to standardize and simplify description of genetic entities, we propose a standard systematic gene nomenclature system for the Brassica genus. This is based upon concatenating abbreviated categories, where these are listed in descending order of significance from left to right (i.e. genus – species – genome – gene name – locus – allele. Indicative examples are provided, and the considerations and recommendations for use are discussed, including outlining the relationship with functionally well-characterized Arabidopsis orthologues. A Brassica Gene Registry has been established under the auspices of the Multinational Brassica Genome Project that will enable management of gene names within the research community, and includes provisional allocation of standard names to genes previously described in the literature or in sequence repositories. The proposed standardization of Brassica gene nomenclature has been distributed to editors of plant and genetics journals and curators of sequence repositories, so that it can be adopted universally.

  10. Revision of genus Steindachneridion (Siluriformes: Pimelodidae

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    Julio Cesar Garavello

    Full Text Available After several years collecting in the type-localities and studying representative samples of genus Steindachneridion Eigenmann & Eigenmann, 1919 from Brazilian and foreign museums, a taxonomic revision of the Recent species of the genus is presented, including the description of a new species from the rio Iguaçu, above the great falls. Steindachneridion species are large sized fishes, reaching 1000 mm total length or more, and sharing some anatomical characters that, at least tentatively, support the monophyly of the genus. In addition to the general features found in the Pimelodidae, the species S. amblyurum (Eigenmann & Eigenmann, 1888, S. parahybae (Steindachner, 1877, S. doceanum (Eigenmann & Eigenmann, 1889, S. scriptum (Miranda Ribeiro, 1918, S. punctatum (Miranda Ribeiro, 1918, and S. melanodermatum, new species, share the shape of the vomer tooth plates, six to eight branched rays in the dorsal-fin, and a low number of gill-rakers. All species, except fossil ones, are redescribed and a key for their identification is provided.

  11. Genus Ranges of 4-Regular Rigid Vertex Graphs.

    Science.gov (United States)

    Buck, Dorothy; Dolzhenko, Egor; Jonoska, Nataša; Saito, Masahico; Valencia, Karin

    2015-01-01

    A rigid vertex of a graph is one that has a prescribed cyclic order of its incident edges. We study orientable genus ranges of 4-regular rigid vertex graphs. The (orientable) genus range is a set of genera values over all orientable surfaces into which a graph is embedded cellularly, and the embeddings of rigid vertex graphs are required to preserve the prescribed cyclic order of incident edges at every vertex. The genus ranges of 4-regular rigid vertex graphs are sets of consecutive integers, and we address two questions: which intervals of integers appear as genus ranges of such graphs, and what types of graphs realize a given genus range. For graphs with 2n vertices (n > 1), we prove that all intervals [a, b] for all a genus ranges. For graphs with 2n - 1 vertices (n ≥ 1), we prove that all intervals [a, b] for all a genus ranges. We also provide constructions of graphs that realize these ranges.

  12. The myxomycete genus Schenella: morphological and DNA sequence evidence for synonymy with the gasteromycete genus Pyrenogaster.

    Science.gov (United States)

    Estrada-Torres, Arturo; Gaither, Thomas W; Miller, Dennis L; Lado, Carlos; Keller, Harold W

    2005-01-01

    The genus Schenella has proven difficult to classify since its description as a new genus in 1911. Macbride placed it with the Myxomycetes but it was unclear with which myxomycete, if any, it should be grouped. Recent identification of abundant samples of Schenella has aided a re-evaluation of its classification as a myxomycete. Morphological evidence based on light and scanning electron microscopy of recently collected specimens and on the type specimen of Macbride suggested that it might be synonymous with the gasteromycete Pyrenogaster Analysis of DNA sequences from freshly isolated samples indicates that the genus Schenella is related closely to an anciently diverged, monophyletic group of fungi that includes several gasteromycete genera, among them Geastrum, Sphaerobolus and Pseudocolus. Comparisons of the morphology and DNA sequences of authentically identified specimens of Pyrenogaster atrogleba indicate that it is synonymous with Schenella simplex. The nomenclatural implications of this discovery are discussed.

  13. Genus paracoccidioides: Species recognition and biogeographic aspects.

    Directory of Open Access Journals (Sweden)

    Raquel Cordeiro Theodoro

    Full Text Available BACKGROUND: Paracoccidioidomycosis is a systemic mycosis caused by Paracoccidioides brasiliensis (species S1, PS2, PS3, and Paracoccidioides lutzii. This work aimed to differentiate species within the genus Paracoccidioides, without applying multilocus sequencing, as well as to obtain knowledge of the possible speciation processes. METHODOLOGY/PRINCIPAL FINDINGS: Single nucleotide polymorphism analysis on GP43, ARF and PRP8 intein genes successfully distinguished isolates into four different species. Morphological evaluation indicated that elongated conidia were observed exclusively in P. lutzii isolates, while all other species (S1, PS2 and PS3 were indistinguishable. To evaluate the biogeographic events that led to the current geographic distribution of Paracoccidioides species and their sister species, Nested Clade and Likelihood Analysis of Geographic Range Evolution (LAGRANGE analyses were applied. The radiation of Paracoccidioides started in northwest South America, around 11-32 million years ago, as calculated on the basis of ARF substitution rate, in the BEAST program. Vicariance was responsible for the divergence among S1, PS2 and P. lutzii and a recent dispersal generated the PS3 species, restricted to Colombia. Taking into account the ancestral areas revealed by the LAGRANGE analysis and the major geographic distribution of L. loboi in the Amazon basin, a region strongly affected by the Andes uplift and marine incursions in the Cenozoic era, we also speculate about the effect of these geological events on the vicariance between Paracoccidioides and L. loboi. CONCLUSIONS/SIGNIFICANCE: The use of at least 3 SNPs, but not morphological criteria, as markers allows us to distinguish among the four cryptic species of the genus Paracoccidioides. The work also presents a biogeographic study speculating on how these species might have diverged in South America, thus contributing to elucidating evolutionary aspects of the genus Paracoccidioides.

  14. Genomic characterization of the Taylorella genus.

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    Laurent Hébert

    Full Text Available The Taylorella genus comprises two species: Taylorella equigenitalis, which causes contagious equine metritis, and Taylorella asinigenitalis, a closely-related species mainly found in donkeys. We herein report on the first genome sequence of T. asinigenitalis, analyzing and comparing it with the recently-sequenced T. equigenitalis genome. The T. asinigenitalis genome contains a single circular chromosome of 1,638,559 bp with a 38.3% GC content and 1,534 coding sequences (CDS. While 212 CDSs were T. asinigenitalis-specific, 1,322 had orthologs in T. equigenitalis. Two hundred and thirty-four T. equigenitalis CDSs had no orthologs in T. asinigenitalis. Analysis of the basic nutrition metabolism of both Taylorella species showed that malate, glutamate and alpha-ketoglutarate may be their main carbon and energy sources. For both species, we identified four different secretion systems and several proteins potentially involved in binding and colonization of host cells, suggesting a strong potential for interaction with their host. T. equigenitalis seems better-equipped than T. asinigenitalis in terms of virulence since we identified numerous proteins potentially involved in pathogenicity, including hemagluttinin-related proteins, a type IV secretion system, TonB-dependent lactoferrin and transferrin receptors, and YadA and Hep_Hag domains containing proteins. This is the first molecular characterization of Taylorella genus members, and the first molecular identification of factors potentially involved in T. asinigenitalis and T. equigenitalis pathogenicity and host colonization. This study facilitates a genetic understanding of growth phenotypes, animal host preference and pathogenic capacity, paving the way for future functional investigations into this largely unknown genus.

  15. Genus Microsporum dermatophytes in Eastern Bohemia.

    Science.gov (United States)

    Dvorák, J; Otcenásek, M

    1976-01-01

    The authors presented a taxonomic survey of dermatophytes of the genus Microsporum. From the 19 species described so far, they isolated ten species in the region of Eastern Bohemia. Only the species Microsporum cookei and M. gypsem are considered to be endemic species. The remaining are regarded as imported dermatophytes which are not able to maintain their existence permanently in the conditions of the mentioned region. Data on the findings of the individual species were completed by the authors' remarks on their primary hosts and/or substrates of heterotrophy, frequency of occurrence and geographical distribution.

  16. A review of the genus Curtisia (Curtisiaceae

    Directory of Open Access Journals (Sweden)

    E. YU Yembaturova

    2009-12-01

    Full Text Available A review of the monotypic southern African endemic genus Curtisia Aiton is presented. Detailed studies of the fruit and seed structure provided new evidence in support of a close relationship between the family Curtisiaceae and Comaceae. Comparisons with several other members of the Comales revealed carpological similarities to certain species of Comus s.I., sometimes treated as segregate genera Dendrobenthamia Hutch, and Benthamidia Spach. We also provide information on the history of the assegai tree, Curtisia dentata (Burm.f. C.A.Sm. and its uses, as well as a formal taxonomic revision, including nomenclature, typification, detailed description and geographical distribution.

  17. The genus Bryoerythrophyllum (Musci, Pottiaceae in Antarctica

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    Sollman Philip

    2015-07-01

    Full Text Available Antarctic material of the genus Bryoerythrophyllum P. C. Chen was studied from all specimens present in KRAM. Bryoerythrophyllum recurvirostrum (Hedw. P. C. Chen var. antarcticum L. I. Savicz & Smirnova is treated as a distinct species: B. antarcticum (L. I. Savicz & Smirnova P. Sollman, stat. nov. Three species are now known in the Antarctic region: B. antarcticum, B. recurvirostrum and B. rubrum (Jur. ex Geh. P. C. Chen. Bryoerythrophyllum rubrum is reported for the first time from the Antarctic. It is a bipolar species. A key to the taxa is given. These species are described and briefly discussed, with notes on illustrations, reproduction, habitat, world range, distribution and elevation in Antarctica.

  18. Polyphasic taxonomy of the genus Talaromyces

    DEFF Research Database (Denmark)

    Yilmaz, N.; Visagie, C.M.; Houbraken, J.

    2014-01-01

    a monograph on Talaromyces applying a polyphasic species concept, including morphological, molecular and physiological characters. Based on an ITS, BenA and RPB2 multigene phylogeny, we propose a new sectional classification for the genus, placing the 88 accepted species into seven sections, named sections...... Bacillispori, Helici, Islandici, Purpurei, Subinflati, Talaromyces and Trachyspermi. We provide morphological descriptions for each of these species, as well as notes on their identification using morphology and DNA sequences. For molecular identification, BenA is proposed as a secondary molecular marker...

  19. A review of the genus Curtisia (Curtisiaceae

    Directory of Open Access Journals (Sweden)

    E. YU Yembaturova

    2009-12-01

    Full Text Available A review of the monotypic southern African endemic genus Curtisia Aiton is presented. Detailed studies of the fruit and seed structure provided new evidence in support of a close relationship between the family Curtisiaceae and Comaceae. Comparisons with several other members of the Comales revealed carpological similarities to certain species of Comus s.I., sometimes treated as segregate genera Dendrobenthamia Hutch, and Benthamidia Spach. We also provide information on the history of the assegai tree, Curtisia dentata (Burm.f. C.A.Sm. and its uses, as well as a formal taxonomic revision, including nomenclature, typification, detailed description and geographical distribution.

  20. Rust fungi on Annonaceae: the genus Sphaerophragmium.

    Science.gov (United States)

    Beenken, Ludwig; Berndt, Reinhard

    2010-01-01

    Seven species of the rust genus Sphaerophragmium occur on members of the tropical plant family Annonaceae. Uropyxis gerstneri is recombined to S. gerstneri. A new species, S. xylopiae, is described from Xylopia acutiflora. The host plant of S. boanense is identified as Mitrella sp. Sphaerophragmium pulchrum is transferred to Dicheirinia. The anatomy of telia with teliospores and parasitizing mycelium is described and illustrated in detail. A new type of M-haustorium, which emanates laterally from intracellular hypha, is detected in S. monodorae. An identification key is given.

  1. Sexual Communication in the Drosophila Genus.

    Science.gov (United States)

    Bontonou, Gwénaëlle; Wicker-Thomas, Claude

    2014-06-18

    In insects, sexual behavior depends on chemical and non-chemical cues that might play an important role in sexual isolation. In this review, we present current knowledge about sexual behavior in the Drosophila genus. We describe courtship and signals involved in sexual communication, with a special focus on sex pheromones. We examine the role of cuticular hydrocarbons as sex pheromones, their implication in sexual isolation, and their evolution. Finally, we discuss the roles of male cuticular non-hydrocarbon pheromones that act after mating: cis-vaccenyl acetate, developing on its controversial role in courtship behavior and long-chain acetyldienylacetates and triacylglycerides, which act as anti-aphrodisiacs in mated females.

  2. The genus Platychara from the Western Hemisphere

    Science.gov (United States)

    Peck, R.E.; Forester, R.M.

    1979-01-01

    The systematics of four species belonging to the genus Platychara (Charophyta) from the Western Hemisphere is discussed. Three of the species, as defined herein, occur in Cretaceous and Paleocene rocks from Mexico through South America. The type species, P. compressa (Peck and Reker) Grambast, also of Cretaceous and Paleocene age, is herein restricted to deposits north of Mexico. These latter restrictions geographically separate P. compressa and P. perlata as presently defined but the relationship between these two species is still uncertain. A new species, P. grambastii, is proposed for specimens from Maestrichtian sediments in Jamaica. ?? 1979.

  3. A Brief Chronicle of the Genus Cordyceps Fr., the Oldest Valid Genus in Cordycipitaceae (Hypocreales, Ascomycota)

    Science.gov (United States)

    Tanaka, Eiji; Han, Jae-Gu; Oh, Junsang; Han, Sang-Kuk; Lee, Kang-Hyo

    2014-01-01

    The earliest pre-Linnaean fungal genera are briefly discussed here with special emphasis on the nomenclatural connection with the genus Cordyceps Fr. Since its valid publication under the basidiomycetous genus Clavaria Vaill. ex L. (Clavaria militaris L. Sp. Pl. 2:1182, 1753), the genus Cordyceps has undergone nomenclatural changes in the post-Linnaean era, but has stood firmly for approximately 200 years. Synonyms of Cordyceps were collected from different literature sources and analyzed based on the species they represent. True synonyms of Cordyceps Fr. were defined as genera that represented species of Cordyceps Fr. emend. G. H. Sung, J. M. Sung, Hywel-Jones & Spatafora. The most common synonyms of Cordyceps observed were Clavaria and Sphaeria Hall, reported in the 18th and in the first half of the 19th century, respectively. Cordyceps, the oldest genus in the Cordyceps s. s. clade of Cordycipitaceae, is the most preferred name under the "One Fungus = One Name" principle on priority bases. PMID:25071376

  4. Regeneration and genetic transformation in the Vitis genus = [Regeneratie en genetische transformatie in het genus Vitis =

    NARCIS (Netherlands)

    Martinelli, L.

    1997-01-01


    This work is a contribution to the development of regeneration systems and genetic transformation in the Vitis genus and opens interesting perspectives to the application of molecular techniques for study interesting traits, as well as for genetic improvement of

  5. Heterogeneity in the genus Allovahlkampfia and the description of the new genus Parafumarolamoeba (Vahlkampfiidae; Heterolobosea).

    Science.gov (United States)

    Geisen, Stefan; Bonkowski, Michael; Zhang, Junling; De Jonckheere, Johan F

    2015-08-01

    Heterolobosean amoebae are common and diverse members of soil protist communities. In this study, we isolated seven strains of amoebae from soil samples taken in Tibet (at high altitude), Sardinia and the Netherlands, all resembling to belong to a similar heterolobosean morphospecies. However, sequences of the small subunit (SSU) rDNA and internal transcribed spacers, including the 5.8S rDNA, revealed a high heterogeneity in the genus Allovahlkampfia to which six of the isolates belong. Some unnamed strains, of which the sequences had been published before, are also included within the genus Allovahlkampfia. One Allovahlkampfia isolated in the Netherlands harbors a twin-ribozyme, containing a His-Cys box, similar to the one found in strain BA of Allovahlkampfia. The other SSU rDNA sequence grouped in phylogenetic analyses with sequences obtained in environmental sequencing studies as sister to the genus Fumarolamoeba. This phylogenetic placement was supported by analyses of the 5.8S rDNA leading us to describe it as a new genus Parafumarolamoeba. Copyright © 2015 Elsevier GmbH. All rights reserved.

  6. The Genus Alpinia: A Review of Its Phytochemistry and Pharmacology

    OpenAIRE

    Wei-Jie Zhang; Jian-Guang Luo; Ling-Yi Kong

    2016-01-01

    Genus Alpinia consists of over 250 species, which are widely distributed in south and southeast Asia. Many plants of genus Alpinia have been used for thousands of years to treat digestive system diseases and as anti-inflammatory drugs. Phytochemical research on this genus has led to the isolation of different kinds of diarylheptanoids, terpenes triterpenoids, phenylbutanoids, lignans, and flavonoids. Experimental evidences revealed that both the crude extracts and pure constituents isolated f...

  7. A MONOGRAPH OF THE GENUS DIPLODISCUS* Turcz. (TILIACEAE

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    A. J. G. H. KOSTERMANS

    2014-01-01

    Full Text Available 1. Seven species of the genus Diplodiscus are described, of which three(D. microlepis, D. parviflorus and D. decumbens are new to science, and one (D. hookerianus was formerly described as Pentace (for the description of D. decumbens cf. p. 264.2. The area of distribution of the genus covers the Malay Peninsula,Borneo and the Philippines.3. The affinities of the genus are discussed.4. A key to the species is presented.

  8. Comparative Genomics Reveals High Genomic Diversity in the Genus Photobacterium

    OpenAIRE

    Henrique Machado; Lone Gram

    2017-01-01

    Vibrionaceae is a large marine bacterial family, which can constitute up to 50% of the prokaryotic population in marine waters. Photobacterium is the second largest genus in the family and we used comparative genomics on 35 strains representing 16 of the 28 species described so far, to understand the genomic diversity present in the Photobacterium genus. Such understanding is important for ecophysiology studies of the genus. We used whole genome sequences to evaluate phylogenetic relationship...

  9. Elliptic Genus of E-strings

    CERN Document Server

    Kim, Joonho; Lee, Kimyeong; Park, Jaemo; Vafa, Cumrun

    2014-01-01

    We study a family of 2d N=(0,4) gauge theories which describes at low energy the dynamics of E-strings, the M2-branes suspended between a pair of M5 and M9 branes. The gauge theory is engineered using a duality with type IIA theory, leading to the D2-branes suspended between an NS5-brane and 8 D8-branes on an O8-plane. We compute the elliptic genus of this family of theories, and find agreement with the known results for single and two E-strings. The partition function can in principle be computed for arbitrary number of E-strings, and we compute them explicitly for low numbers. We test our predictions against the partially known results from topological strings, as well as from the instanton calculus of 5d Sp(1) gauge theory. Given the relation to topological strings, our computation provides the all genus partition function of the refined topological strings on the canonical bundle over 1/2 K3.

  10. Magnaporthiopsis, a new genus in Magnaporthaceae (Ascomycota).

    Science.gov (United States)

    Luo, Jing; Zhang, Ning

    2013-01-01

    The phylogenetic relationships among taxa in the Magnaporthaceae are investigated based on DNA sequences of multiple genes including SSU, ITS, LSU, MCM7, RPB1 and TEF1. The genera Magnaporthe and Gaeumannomyces are shown to be polyphyletic and their members are divided into four major groups based on the phylogenetic analyses. Considering morphological, biological and molecular data, we establish a new genus, Magnaporthiopsis. It is characterized by black and globose perithecia with a cylindrical neck, two-layered perithecial wall, clavate asci with a refractive apical ring, fusiform to fusoid and septate ascospores, simple hyphopodia, and Phialophora-like anamorph. Species in this genus are necrotrophic parasites infecting roots of grasses. Three new combinations, Magnaporthiopsis poae, M. rhizophila and M. incrustans, are proposed accordingly. Pyricularia is suggested as the generic name for the rice blast fungus over Magnaporthe, following Article 59.1 of the International Code of Nomenclature for algae, fungi and plants. A new combination, Nakataea oryzae, is proposed for the rice stem rot fungus.

  11. Genus Tinospora: Ethnopharmacology, Phytochemistry, and Pharmacology

    Science.gov (United States)

    She, Gaimei; Han, Dan; Wang, Weihua; Liu, Zhao

    2016-01-01

    The genus Tinospora includes 34 species, in which several herbs were used as traditional medicines by indigenous groups throughout the tropical and subtropical parts of Asia, Africa, and Australia. The extensive literature survey revealed Tinospora species to be a group of important medicinal plants used for the ethnomedical treatment of colds, headaches, pharyngitis, fever, diarrhea, oral ulcer, diabetes, digestive disorder, and rheumatoid arthritis. Indian ethnopharmacological data points to the therapeutic potential of the T. cordifolia for the treatment of diabetic conditions. While Tinospora species are confusing in individual ingredients and their mechanisms of action, the ethnopharmacological history of those plants indicated that they exhibit antidiabetic, antioxidation, antitumor, anti-inflammation, antimicrobial, antiosteoporosis, and immunostimulation activities. While the clinical applications in modern medicine are lacking convincing evidence and support, this review is aimed at summarizing the current knowledge of the traditional uses, phytochemistry, biological activities, and toxicities of the genus Tinospora to reveal its therapeutic potentials and gaps, offering opportunities for future researches. PMID:27648105

  12. The genus Geobacillus and their biotechnological potential.

    Science.gov (United States)

    Hussein, Ali H; Lisowska, Beata K; Leak, David J

    2015-01-01

    The genus Geobacillus comprises a group of Gram-positive thermophilic bacteria, including obligate aerobes, denitrifiers, and facultative anaerobes that can grow over a range of 45-75°C. Originally classified as group five Bacillus spp., strains of Bacillus stearothermophilus came to prominence as contaminants of canned food and soon became the organism of choice for comparative studies of metabolism and enzymology between mesophiles and thermophiles. More recently, their catabolic versatility, particularly in the degradation of hemicellulose and starch, and rapid growth rates have raised their profile as organisms with potential for second-generation (lignocellulosic) biorefineries for biofuel or chemical production. The continued development of genetic tools to facilitate both fundamental investigation and metabolic engineering is now helping to realize this potential, for both metabolite production and optimized catabolism. In addition, this catabolic versatility provides a range of useful thermostable enzymes for industrial application. A number of genome-sequencing projects have been completed or are underway allowing comparative studies. These reveal a significant amount of genome rearrangement within the genus, the presence of large genomic islands encompassing all the hemicellulose utilization genes and a genomic island incorporating a set of long chain alkane monooxygenase genes. With G+C contents of 45-55%, thermostability appears to derive in part from the ability to synthesize protamine and spermine, which can condense DNA and raise its Tm.

  13. Genus Tinospora: Ethnopharmacology, Phytochemistry, and Pharmacology

    Directory of Open Access Journals (Sweden)

    Sensen Chi

    2016-01-01

    Full Text Available The genus Tinospora includes 34 species, in which several herbs were used as traditional medicines by indigenous groups throughout the tropical and subtropical parts of Asia, Africa, and Australia. The extensive literature survey revealed Tinospora species to be a group of important medicinal plants used for the ethnomedical treatment of colds, headaches, pharyngitis, fever, diarrhea, oral ulcer, diabetes, digestive disorder, and rheumatoid arthritis. Indian ethnopharmacological data points to the therapeutic potential of the T. cordifolia for the treatment of diabetic conditions. While Tinospora species are confusing in individual ingredients and their mechanisms of action, the ethnopharmacological history of those plants indicated that they exhibit antidiabetic, antioxidation, antitumor, anti-inflammation, antimicrobial, antiosteoporosis, and immunostimulation activities. While the clinical applications in modern medicine are lacking convincing evidence and support, this review is aimed at summarizing the current knowledge of the traditional uses, phytochemistry, biological activities, and toxicities of the genus Tinospora to reveal its therapeutic potentials and gaps, offering opportunities for future researches.

  14. Polyphasic taxonomy of the genus Talaromyces.

    Science.gov (United States)

    Yilmaz, N; Visagie, C M; Houbraken, J; Frisvad, J C; Samson, R A

    2014-06-01

    The genus Talaromyces was described by Benjamin in 1955 as a sexual state of Penicillium that produces soft walled ascomata covered with interwoven hyphae. Phylogenetic information revealed that Penicillium subgenus Biverticillium and Talaromyces form a monophyletic clade distinct from the other Penicillium subgenera. Subsequently, in combination with the recent adoption of the one fungus one name concept, Penicillium subgenus Biverticillium was transferred to Talaromyces. At the time, the new combinations were made based only on phylogenetic information. As such, the aim of this study was to provide a monograph on Talaromyces applying a polyphasic species concept, including morphological, molecular and physiological characters. Based on an ITS, BenA and RPB2 multigene phylogeny, we propose a new sectional classification for the genus, placing the 88 accepted species into seven sections, named sections Bacillispori, Helici, Islandici, Purpurei, Subinflati, Talaromyces and Trachyspermi. We provide morphological descriptions for each of these species, as well as notes on their identification using morphology and DNA sequences. For molecular identification, BenA is proposed as a secondary molecular marker to the accepted ITS barcode for fungi.

  15. Aggressive behavior in the genus Gallus sp

    Directory of Open Access Journals (Sweden)

    SA Queiroz

    2006-03-01

    Full Text Available The intensification of the production system in the poultry industry and the vertical integration of the poultry agribusiness have brought profound changes in the physical and social environment of domestic fowls in comparison to their ancestors and have modified the expression of aggression and submission. The present review has covered the studies focusing on the different aspects linked to aggressiveness in the genus Gallus. The evaluated studies have shown that aggressiveness and subordination are complex behavioral expressions that involve genetic differences between breeds, strains and individuals, and differences in the cerebral development during growth, in the hormonal metabolism, in the rearing conditions of individuals, including feed restriction, density, housing type (litter or cage, influence of the opposite sex during the growth period, existence of hostile stimuli (pain and frustration, ability to recognize individuals and social learning. The utilization of fighting birds as experimental material in the study of mechanisms that have influence on the manifestation of aggressiveness in the genus Gallus might comparatively help to elucidate important biological aspects of such behavior.

  16. Topological classification and enumeration of RNA structures by genus

    DEFF Research Database (Denmark)

    Andersen, Jørgen Ellegaard; Penner, Robert; Reidys, C. M.

    2013-01-01

    To an RNA pseudoknot structure is naturally associated a topological surface, which has its associated genus, and structures can thus be classified by the genus. Based on earlier work of Harer-Zagier, we compute the generating function for the number of those structures of fixed genus and minimum...... stack size with nucleotides so that no two consecutive nucleotides are basepaired and show that is algebraic. In particular, we prove that , where . Thus, for stack size at least two, the genus only enters through the sub-exponential factor, and the slow growth rate compared to the number of RNA...

  17. Transfer of Methanolobus siciliae to the genus Methanosarcina, naming it Methanosarcina siciliae, and emendation of the genus Methanosarcina

    Science.gov (United States)

    Ni, S.; Woese, C. R.; Aldrich, H. C.; Boone, D. R.

    1994-01-01

    A sequence analysis of the 16S rRNA of Methanolobus siciliae T4/M(T) (T = type strain) showed that this strain is closely related to members of the genus Methanosarcina, especially Methanosarcina acetivorans C2A(T). Methanolobus siciliae T4/M(T) and HI350 were morphologically more similar to members of the genus Methanosarcina than to members of the genus Methanolobus in that they both formed massive cell aggregates with pseudosarcinae. Thus, we propose that Methanolobus siciliae should be transferred to the genus Methanosarcina as Methanosarcina siciliae.

  18. Revision of genus Steindachneridion (Siluriformes: Pimelodidae

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    Julio Cesar Garavello

    2005-12-01

    Full Text Available After several years collecting in the type-localities and studying representative samples of genus Steindachneridion Eigenmann & Eigenmann, 1919 from Brazilian and foreign museums, a taxonomic revision of the Recent species of the genus is presented, including the description of a new species from the rio Iguaçu, above the great falls. Steindachneridion species are large sized fishes, reaching 1000 mm total length or more, and sharing some anatomical characters that, at least tentatively, support the monophyly of the genus. In addition to the general features found in the Pimelodidae, the species S. amblyurum (Eigenmann & Eigenmann, 1888, S. parahybae (Steindachner, 1877, S. doceanum (Eigenmann & Eigenmann, 1889, S. scriptum (Miranda Ribeiro, 1918, S. punctatum (Miranda Ribeiro, 1918, and S. melanodermatum, new species, share the shape of the vomer tooth plates, six to eight branched rays in the dorsal-fin, and a low number of gill-rakers. All species, except fossil ones, are redescribed and a key for their identification is provided.Após vários anos coletando nas localidades tipo e estudando amostras representativas de museus brasileiros e estrangeiros, é apresentada uma revisão taxonômica das espécies Recentes do gênero Steindachneridion Eigenmann & Eigenmann, 1919, incluindo a descrição de uma espécie nova da bacia do rio Iguaçu, acima das Cataratas do Iguaçu. Em comum, os adultos de todas as espécies apresentam grande porte, até 1000 mm ou mais de comprimento padrão e compartilham alguns caracteres anatômicos discutidos neste estudo, que pelo menos preliminarmente suportam o monofiletismo do gênero. Além das características gerais de Pimelodidae, S. amblyurum (Eigenmann & Eigenmann, 1888, S. parahybae (Steindachner, 1877, S. doceanum (Eigenmann & Eigenmann, 1889, S. scriptum (Miranda Ribeiro, 1918, S. punctatum (Miranda Ribeiro, 1918 e S. melanodermatum, espécie nova, têm em comum a forma das placas dentígeras do

  19. The genus Schoenoxiphium (Cyperaceae. A preliminary account

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    I. Kukkonen

    1983-12-01

    Full Text Available The genus Schoenoxiphium of the tribe Cariceae of Cyperaceae is conservatively accepted as being restricted to the African continent and Madagascar. The special features of the inflorescence structure are described. The following species are provisionally recognized: S. basutorum Turrill, S. distinctum Kukkonen, S. ecklonii Nees, S.  filiforme Kükenthal, S. gracile Chermezon, S. lanceum (Thunberg Kukenthal, S. lehmannii (Nees Steudel, S.  madagascariense Chermezon, S. perdensum Kukkonen, S. rufum Nees, S. schweickerdtii Merxmiiller & Podlech, and  S. sparteum (Wahlenberg Kukenthal. A key to the species is provided and their distribution is roughly outlined. The morphological variation within the species suggests separation of taxa below specific level, or perhaps even at species level, but this will require more detailed information about the ecology, distribution and the cytology.

  20. Review: Natural products from Genus Selaginella (Selaginellaceae

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    AHMAD DWI SETYAWAN

    2011-01-01

    Full Text Available Setyawan AD. 2011. Natural products from Genus Selaginella (Selaginellaceae. Nusantara Bioscience 3: 44-58. Selaginella is a potent medicinal-stuff, which contains diverse of natural products such as alkaloid, phenolic (flavonoid, and terpenoid. This species is traditionally used to cure several diseases especially for wound, after childbirth, and menstrual disorder. Biflavonoid, a dimeric form of flavonoids, is the most valuable natural products of Selaginella, which constituted at least 13 compounds, namely amentoflavone, 2',8''-biapigenin, delicaflavone, ginkgetin, heveaflavone, hinokiflavone, isocryptomerin, kayaflavone, ochnaflavone, podocarpusflavone A, robustaflavone, sumaflavone, and taiwaniaflavone. Ecologically, plants use biflavonoid to response environmental condition such as defense against pests, diseases, herbivory, and competitions; while human medically use biflavonoid especially for antioxidant, anti-inflammatory, and anti carcinogenic. Selaginella also contains valuable disaccharide, namely trehalose that has long been known for protecting from desiccation and allows surviving severe environmental stress. The compound has very prospects as molecular stabilizer in the industries based bioresources.

  1. The genus Schoenoxiphium (Cyperaceae. A preliminary account

    Directory of Open Access Journals (Sweden)

    I. Kukkonen

    1983-12-01

    Full Text Available The genus Schoenoxiphium of the tribe Cariceae of Cyperaceae is conservatively accepted as being restricted to the African continent and Madagascar. The special features of the inflorescence structure are described. The following species are provisionally recognized: S. basutorum Turrill, S. distinctum Kukkonen, S. ecklonii Nees, S.  filiforme Kükenthal, S. gracile Chermezon, S. lanceum (Thunberg Kukenthal, S. lehmannii (Nees Steudel, S.  madagascariense Chermezon, S. perdensum Kukkonen, S. rufum Nees, S. schweickerdtii Merxmiiller & Podlech, and  S. sparteum (Wahlenberg Kukenthal. A key to the species is provided and their distribution is roughly outlined. The morphological variation within the species suggests separation of taxa below specific level, or perhaps even at species level, but this will require more detailed information about the ecology, distribution and the cytology.

  2. [CITRULLINUREIDASE GENE DIVERSITY IN THE GENUS FRANCISELLA].

    Science.gov (United States)

    Timofeev, V S; Bakhteeva, I V; Pavlov, V M; Mokrievich, A N

    2015-01-01

    This work describes the results, of the in silico analysis of the genetic diversity of the citrullinureidase gene (ctu) in two species of bacteria of the genus Francisella: tularensis (ssp. tularensis, holarctica, mediasiatica, novicida) and philomiragia. The strains of the Central Asiatic subspecies possessing the citrullinureidase activity differ in the gene ctu from the ssp tularensis Schu by three nucleotide substitutions leading to two insignificant amino acid substitutions in the encoded polypeptide. In the strain F. tularensis of the ssp. holarctica the gene ctu encodes inactive enzyme, which is probably due to amino acid substitutions: 151 Gly --> Asp, 183 Pro --> Leu, 222 Asp --> Asn. Except for the Japan biovar bacteria, in all strains of the Holarctic subspecies there are two stop codons in the gene ctu. The bacteria of the subspecies novicida contain the ctu gene only in the strain 3523, whereas the other strains contain the gene FTN_0827 encoding the C-N hydrolase, which probably provides the citrullinureidase activity.

  3. Molecular phylogenetics of the hummingbird genus Coeligena.

    Science.gov (United States)

    Parra, Juan Luis; Remsen, J V; Alvarez-Rebolledo, Mauricio; McGuire, Jimmy A

    2009-11-01

    Advances in the understanding of biological radiations along tropical mountains depend on the knowledge of phylogenetic relationships among species. Here we present a species-level molecular phylogeny based on a multilocus dataset for the Andean hummingbird genus Coeligena. We compare this phylogeny to previous hypotheses of evolutionary relationships and use it as a framework to understand patterns in the evolution of sexual dichromatism and in the biogeography of speciation within the Andes. Previous phylogenetic hypotheses based mostly on similarities in coloration conflicted with our molecular phylogeny, emphasizing the unreliability of color characters for phylogenetic inference. Two major clades, one monochromatic and the other dichromatic, were found in Coeligena. Closely related species were either allopatric or parapatric on opposite mountain slopes. No sister lineages replaced each other along an elevational gradient. Our results indicate the importance of geographic isolation for speciation in this group and the potential interaction between isolation and sexual selection to promote diversification.

  4. Environmental Origin of the Genus Bordetella

    Science.gov (United States)

    Hamidou Soumana, Illiassou; Linz, Bodo; Harvill, Eric T.

    2017-01-01

    Members of the genus Bordetella include human and animal pathogens that cause a variety of respiratory infections, including whooping cough in humans. Despite the long known ability to switch between a within-animal and an extra-host lifestyle under laboratory growth conditions, no extra-host niches of pathogenic Bordetella species have been defined. To better understand the distribution of Bordetella species in the environment, we probed the NCBI nucleotide database with the 16S ribosomal RNA (16S rRNA) gene sequences from pathogenic Bordetella species. Bacteria of the genus Bordetella were frequently found in soil, water, sediment, and plants. Phylogenetic analyses of their 16S rRNA gene sequences showed that Bordetella recovered from environmental samples are evolutionarily ancestral to animal-associated species. Sequences from environmental samples had a significantly higher genetic diversity, were located closer to the root of the phylogenetic tree and were present in all 10 identified sequence clades, while only four sequence clades possessed animal-associated species. The pathogenic bordetellae appear to have evolved from ancestors in soil and/or water. We show that, despite being animal-adapted pathogens, Bordetella bronchiseptica, and Bordetella hinzii have preserved the ability to grow and proliferate in soil. Our data implicate soil as a probable environmental origin of Bordetella species, including the animal-pathogenic lineages. Soil may further constitute an environmental niche, allowing for persistence and dissemination of the bacterial pathogens. Spread of pathogenic bordetellae from an environmental reservoir such as soil may potentially explain their wide distribution as well as frequent disease outbreaks that start without an obvious infectious source. PMID:28174558

  5. Small RNAs in the genus Clostridium.

    Science.gov (United States)

    Chen, Yili; Indurthi, Dinesh C; Jones, Shawn W; Papoutsakis, Eleftherios T

    2011-01-25

    The genus Clostridium includes major human pathogens and species important to cellulose degradation, the carbon cycle, and biotechnology. Small RNAs (sRNAs) are emerging as crucial regulatory molecules in all organisms, but they have not been investigated in clostridia. Research on sRNAs in clostridia is hindered by the absence of a systematic method to identify sRNA candidates, thus delegating clostridial sRNA research to a hit-and-miss process. Thus, we wanted to develop a method to identify potential sRNAs in the Clostridium genus to open up the field of sRNA research in clostridia. Using comparative genomics analyses combined with predictions of rho-independent terminators and promoters, we predicted sRNAs in 21 clostridial genomes: Clostridium acetobutylicum, C. beijerinckii, C. botulinum (eight strains), C. cellulolyticum, C. difficile, C. kluyveri (two strains), C. novyi, C. perfringens (three strains), C. phytofermentans, C. tetani, and C. thermocellum. Although more than one-third of predicted sRNAs have Shine-Dalgarno (SD) sequences, only one-sixth have a start codon downstream of SD sequences; thus, most of the predicted sRNAs are noncoding RNAs. Quantitative reverse transcription-PCR (Q-RT-PCR) and Northern analysis were employed to test the presence of a randomly chosen set of sRNAs in C. acetobutylicum and several C. botulinum strains, leading to the confirmation of a large fraction of the tested sRNAs. We identified a conserved, novel sRNA which, together with the downstream gene coding for an ATP-binding cassette (ABC) transporter gene, responds to the antibiotic clindamycin. The number of predicted sRNAs correlated with the physiological function of the species (high for pathogens, low for cellulolytic, and intermediate for solventogenic), but not with 16S rRNA-based phylogeny.

  6. Revision of the genus Paratropus Gerstaecker (Coleoptera: Histeridae)

    NARCIS (Netherlands)

    Kanaar, P.

    1997-01-01

    The myrmecophilous and termitophilous genus Paratropus Gerstaecker is revised and figured. A key to the species is given. The number of species in this genus has been brought up to 80, of which 31 species are described as new: P. arriagadai (Tanzania), P. bakxi (Zaire), P. baloghi (Congo, Zaire, Rua

  7. The neotropical genus Opeatocerata Melander (Díptera, Empididae

    Directory of Open Access Journals (Sweden)

    Kenneth G. V. Smith

    1989-01-01

    Full Text Available The Neotropical empidid genus Opeatocerata Melander, hitherto known from only a sigle female from Mexico, is redefined in the light of new material, including males. Three new species are described and illustrated, a key provided and the presence of the genus now additionally established in Costa Rica, Panama, Bolivia, Ecuador, Trinidad and Brazil.

  8. Phylogeny of the Peckia-genus group

    DEFF Research Database (Denmark)

    Buenaventura Ruiz, Ingrid Eliana; Pape, Thomas

    2015-01-01

    Peckia is the most species-rich necrophagous genus among the Neotropical sarcophagids, encompassing 67 species distributed in 5 subgenera. Recent phylogenetic studies have challenged the monophyly of this genus with regard to species of the genera Peckiamyia, Titanogrypa, and Villegasia, and the ...

  9. Molecular phylogeny and taxonomy of the genus Veloporphyrellus

    Science.gov (United States)

    Yan-Chun Li; Beatriz Ortiz-Santana; Nian-Kai Zeng; Bang Feng; Zhu L. Yang

    2014-01-01

    Veloporphyrellus is a genus known from North and Central America, southeastern Asia, and Africa. Because species of this genus are phenotypically similar to some taxa in several genera, such as Boletellus, Leccinum, Strobilomyces, Suillus and Tylopilus s.l. belonging to Boletales, its phylogenetic disposition has...

  10. Revision of the genus Trypeticus Marseul (Coleoptera: Histeridae)

    NARCIS (Netherlands)

    Kanaar, P.

    2003-01-01

    The genus Trypeticus Marseul, 1864 is revised and figured. A key to the species is given. Redescriptions of the hitherto described species are presented. The number of species in this genus has been brought up to 100, of which 72 species are described as new: T. adebratti (Sabah, Brunei), T. alticol

  11. Note on the genus Barteria Hook. f. (Flacourtiaceae or Passifloraceae)

    NARCIS (Netherlands)

    Sleumer, H.

    1974-01-01

    The discrimination of species in the genus Barteria has become more and more difficult with the increasing number of collections in recent years. To explain his treatment of the genus in the forthcoming 2nd part of the Flacourtiaceae in the ‘Flore d’Afrique Central (Zaire-Rwanda-Burundi)’, the autho

  12. The phyletic status of the genus Planaria (Platyhelminthes, Turbellaria, Tricladida)

    NARCIS (Netherlands)

    Ball, Ian R.; Gourbault, Nicole

    1978-01-01

    The amphiatlantic distribution of the genus Planaria is incompatible with our current hypothesis of the historical biogeography of freshwater planarians. New anatomical studies suggest the possibility that the genus is not strictly monophyletic; new karyological data are strongly corroborative of th

  13. Notes on the genus Pirdana Distant, 1886 (Lepidoptera: Hesperiidae)

    NARCIS (Netherlands)

    Jong, de R.; Treadaway, C.G.

    1993-01-01

    In the Oriental genus Pirdana Distant, 1886, the new species P. fusca is described from Samar (E Philippines). The phylogeny of the genus is discussed and as a consequence the endemic Sulawesi taxon P. hyela ismene (Felder & Felder, [1867]) is given back its species rank, bringing the total number o

  14. Constant factor approximation to the bounded genus instances of ATSP

    CERN Document Server

    Gharan, Shayan Oveis

    2009-01-01

    We give a constant factor approximation algorithm for the asymmetric traveling salesman problem when the underlying undirected graph of the Held-Karp linear programming relaxation of the problem has orientable bounded genus. Our result also implies the weak version Goddyn's conjecture on the existence of thin trees on graphs with orientable bounded genus.

  15. Genus-zero Whitham hierarchies in conformal-map dynamics

    Energy Technology Data Exchange (ETDEWEB)

    Martinez-Alonso, Luis [Departamento de Fisica Teorica II, Universidad Complutense, E-28040 Madrid (Spain)]. E-mail: luism@fis.ucm.es; Medina, Elena [Departamento de Matematicas, Universidad de Cadiz, E-11510 Puerto Real, Cadiz (Spain)

    2006-10-26

    A scheme for solving quasiclassical string equations is developed to prove that genus-zero Whitham hierarchies describe the deformations of planar domains determined by rational conformal maps. This property is applied in normal matrix models to show that deformations of simply-connected supports of eigenvalues under changes of coupling constants are governed by genus-zero Whitham hierarchies.

  16. Tsiangia, a new genus based on Gaertnera Hongkongensis (Rubiaceae)

    NARCIS (Netherlands)

    But, P. Pui-Hay; Hsue, Hsiang-hao; Li, Ping-T’ao

    1986-01-01

    Detailed examination of the holotype and isotype of Gaertnera hongkongensis Seemann led to the conclusion that this species does not belong to Gaertnera nor to Randia. A new genus, Tsiangia, is proposed to accommodate the new combination Tsiangia hongkongensis. This new genus is retained in Rubiacea

  17. Revision of the genus Paratropus Gerstaecker (Coleoptera: Histeridae)

    NARCIS (Netherlands)

    Kanaar, P.

    1997-01-01

    The myrmecophilous and termitophilous genus Paratropus Gerstaecker is revised and figured. A key to the species is given. The number of species in this genus has been brought up to 80, of which 31 species are described as new: P. arriagadai (Tanzania), P. bakxi (Zaire), P. baloghi (Congo, Zaire,

  18. A note on the genus Liocranium Ogilby (Pisces, Scorpaenidae)

    NARCIS (Netherlands)

    Mees, G.F.

    1964-01-01

    The genus Liocranium was established by Ogilby (1903) to contain a new species of scorpion-fish from the east coast of Queensland: L. praepositum. The genus remained monotypic until McCulloch (1921) placed Paracentropogan scorpio Ogilby in it, a species also described from the Queensland coast. Whit

  19. Calongea, a new genus of truffles in the Pezizaceae (Pezizales)

    Science.gov (United States)

    Rosanne A. Healy; Gregory Bonito; James M. Trappe

    2009-01-01

    Phylogenetic analysis of the ITS and LSU rDNA of Pachyphloeus species from Europe and North America revealed a new truffle genus. These molecular analyses plus sequences downloaded from a BLAST search in GenBank indicated that Pachyphloeus prieguensis is within the Pezizaceae but well outside of the genus Pachyphloeus...

  20. A revision of the genus Cratoxylum Bl. (Guttiferae)

    NARCIS (Netherlands)

    Gogelein, A.J.F.

    1967-01-01

    A complete revision is given of the Indo-Malesian genus Cratoxylum. The subdivision of the genus into 3 sections, as given by Engler (1925) and Corner (1939), has been found correct. The characters by which these sections are discriminated concern the interpetiolar scars on the twig, the type of ven

  1. The Genus Alpinia: A Review of Its Phytochemistry and Pharmacology

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    Wei-Jie Zhang

    2016-01-01

    Full Text Available Genus Alpinia consists of over 250 species, which are widely distributed in south and southeast Asia. Many plants of genus Alpinia have been used for thousands of years to treat digestive system diseases and as anti-inflammatory drugs. Phytochemical research on this genus has led to the isolation of different kinds of diarylheptanoids, terpenes triterpenoids, phenylbutanoids, lignans, and flavonoids. Experimental evidences revealed that both the crude extracts and pure constituents isolated from the genus Alpinia exhibit a wide range of bioactivities such as anti-cancer, anti-oxidant, anti-bacterial, anti-viral, cardiovascular, and digestive system protective effects. Here, we summarize the phytochemistry and pharmacology investigation of the genus Alpinia, which can provide reference for further research and drug development.

  2. Log-concavity of the genus polynomials of Ringel Ladders

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    Jonathan L Gross

    2015-10-01

    Full Text Available A Ringel ladder can be formed by a self-bar-amalgamation operation on a symmetric ladder, that is, by joining the root vertices on its end-rungs. The present authors have previously derived criteria under which linear chains of copies of one or more graphs have log-concave genus polyno- mials. Herein we establish Ringel ladders as the first significant non-linear infinite family of graphs known to have log-concave genus polynomials. We construct an algebraic representation of self-bar-amalgamation as a matrix operation, to be applied to a vector representation of the partitioned genus distribution of a symmetric ladder. Analysis of the resulting genus polynomial involves the use of Chebyshev polynomials. This paper continues our quest to affirm the quarter-century-old conjecture that all graphs have log-concave genus polynomials.

  3. On RNA-RNA interaction structures of fixed topological genus.

    Science.gov (United States)

    Fu, Benjamin M M; Han, Hillary S W; Reidys, Christian M

    2015-04-01

    Interacting RNA complexes are studied via bicellular maps using a filtration via their topological genus. Our main result is a new bijection for RNA-RNA interaction structures and a linear time uniform sampling algorithm for RNA complexes of fixed topological genus. The bijection allows to either reduce the topological genus of a bicellular map directly, or to lose connectivity by decomposing the complex into a pair of single stranded RNA structures. Our main result is proved bijectively. It provides an explicit algorithm of how to rewire the corresponding complexes and an unambiguous decomposition grammar. Using the concept of genus induction, we construct bicellular maps of fixed topological genus g uniformly in linear time. We present various statistics on these topological RNA complexes and compare our findings with biological complexes. Furthermore we show how to construct loop-energy based complexes using our decomposition grammar. Copyright © 2015 Elsevier Inc. All rights reserved.

  4. Genomes-based phylogeny of the genus Xanthomonas

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    Rodriguez-R Luis M

    2012-03-01

    Full Text Available Abstract Background The genus Xanthomonas comprises several plant pathogenic bacteria affecting a wide range of hosts. Despite the economic, industrial and biological importance of Xanthomonas, the classification and phylogenetic relationships within the genus are still under active debate. Some of the relationships between pathovars and species have not been thoroughly clarified, with old pathovars becoming new species. A change in the genus name has been recently suggested for Xanthomonas albilineans, an early branching species currently located in this genus, but a thorough phylogenomic reconstruction would aid in solving these and other discrepancies in this genus. Results Here we report the results of the genome-wide analysis of DNA sequences from 989 orthologous groups from 17 Xanthomonas spp. genomes available to date, representing all major lineages within the genus. The phylogenetic and computational analyses used in this study have been automated in a Perl package designated Unus, which provides a framework for phylogenomic analyses which can be applied to other datasets at the genomic level. Unus can also be easily incorporated into other phylogenomic pipelines. Conclusions Our phylogeny agrees with previous phylogenetic topologies on the genus, but revealed that the genomes of Xanthomonas citri and Xanthomonas fuscans belong to the same species, and that of Xanthomonas albilineans is basal to the joint clade of Xanthomonas and Xylella fastidiosa. Genome reduction was identified in the species Xanthomonas vasicola in addition to the previously identified reduction in Xanthomonas albilineans. Lateral gene transfer was also observed in two gene clusters.

  5. Analysis of synonymous codon usage patterns in the genus Rhizobium.

    Science.gov (United States)

    Wang, Xinxin; Wu, Liang; Zhou, Ping; Zhu, Shengfeng; An, Wei; Chen, Yu; Zhao, Lin

    2013-11-01

    The codon usage patterns of rhizobia have received increasing attention. However, little information is available regarding the conserved features of the codon usage patterns in a typical rhizobial genus. The codon usage patterns of six completely sequenced strains belonging to the genus Rhizobium were analysed as model rhizobia in the present study. The relative neutrality plot showed that selection pressure played a role in codon usage in the genus Rhizobium. Spearman's rank correlation analysis combined with correspondence analysis (COA) showed that the codon adaptation index and the effective number of codons (ENC) had strong correlation with the first axis of the COA, which indicated the important role of gene expression level and the ENC in the codon usage patterns in this genus. The relative synonymous codon usage of Cys codons had the strongest correlation with the second axis of the COA. Accordingly, the usage of Cys codons was another important factor that shaped the codon usage patterns in Rhizobium genomes and was a conserved feature of the genus. Moreover, the comparison of codon usage between highly and lowly expressed genes showed that 20 unique preferred codons were shared among Rhizobium genomes, revealing another conserved feature of the genus. This is the first report of the codon usage patterns in the genus Rhizobium.

  6. A review of the genus Hyoscyamus (Solanaceae in Iran

    Directory of Open Access Journals (Sweden)

    شادی حاج رسولیها

    2015-12-01

    Full Text Available The genus Hyoscyamus is belonging to the family Solanaceae. This genus with 12-19 species has a wide range of distribution in Iran. In different flora, some species of this genus are synonym due the similar morphology. Three subgenera are introduced for genus namely Hyoscyamus, Parahyoscyamus and Dendrotrichon in Iran. For accurate survey done the general review on this genus. For morphological studies the images of calyx species were plotted with stereo microscope with specified enlarge. For numerical taxonomy studies 42 qualitative and quantitative morphological characters were selected and analyzed with SPSS software with three methods cluster, PCA and FA. Then the results of analysis compared and reconciled with data from various studies conducted on this genus. Survey data confirmed the approximation of two species H.tenuicaulis and H. bornmulleri and H. bornmulleri is the synonym of H. tenuicaulis. Also, H. malekianus transferred from subgen. Parahyoscyamus to subgen. Dendrotrichon. Finally, a key to all species of the genus Hyoscyamus in Iran is provided.

  7. The genus Allium--Part 1.

    Science.gov (United States)

    Fenwick, G R; Hanley, A B

    1985-01-01

    Alliums have been grown for many centuries for their characteristic, pungent flavor and medicinal properties. The present review, which includes references published up to the middle of 1984, is primarily concerned with the chemical composition, flavor, and physiological properties of these crops, their extracts, and processed products. Special emphasis is placed upon the relationship between the organoleptically and biologically active components of onion and garlic. Following a brief historical introduction, current production of commercially important alliums is described and their botanical origins and interrelationships are explained. Following consideration of the major economic diseases and pests of alliums, the agronomic, husbandry, and practices associated with their cultivation are described, particular emphasis being placed upon the storage and processing of onion and garlic. The detailed, overall chemical composition and nutritional value of members of the genus Allium are presented in Section 7; after an outline of the origin and nature of flavor components and precursors, the flavor volatiles of individual members are presented. The effects of agronomic, environmental, and processing practices on chemical and flavor content and quality are considered in Section 9. The following section deals critically with the human and animal studies which have been conducted into the medical and therapeutic properties of alliums, emphasis being placed upon the studies into the antiatherosclerotic effect of onion and garlic and their essential oils. After a study of antimicrobial properties of alliums and their effects on insects and animals, an overview is presented which highlights unexplored or inadequately studied areas and suggests rewarding areas for future research.

  8. Mycorrhizal status of the genus Carex (Cyperaceae).

    Energy Technology Data Exchange (ETDEWEB)

    Miller, R. M.; Smith, C. I.; Jastrow, J. D.; Bever, J. D.; Environmental Research; Univ. of Chicago

    1999-01-01

    The Cyperaccae have generally been considered nonmycorrhizal, although recent evidence suggests that mycotrophy may be considerably more widespread among sedges than was previously realized. This study surveyed 23 species of Carex occurring in upland and wetland habitats in northeastern Illinois. Mycorrhizal infection by arbuscular fungi was found in the roots of 16 species of Carex and appears to occur in response to many factors, both environmental and phylogenetic. While some species appear to be obligately nonmycorrhizal, edaphic influences may be responsible for infection in others. In five of the seven Carex species that were nonmycorrrhizal, a novel root character, the presence of bulbous-based root hairs, was identified. The taxonomically patchy distribution of the distinctive root hair trait suggests that these structures may have evolved several times within the genus. Evidence of multiple independent origins of the root hair trait lends support to the hypothesis that root hairs represent an adaptation to nonmycotrophy. Although taxonomic position does seem to be of importance in determining the mycorrhizal dependence of sedges, the pattern may be a patchwork of both mycorrhizal clades and clades that have adapted to the nonmycorrhizal state.

  9. Multilocus phylogenetic analysis of the genus Aeromonas.

    Science.gov (United States)

    Martinez-Murcia, Antonio J; Monera, Arturo; Saavedra, M Jose; Oncina, Remedios; Lopez-Alvarez, Monserrate; Lara, Erica; Figueras, M Jose

    2011-05-01

    A broad multilocus phylogenetic analysis (MLPA) of the representative diversity of a genus offers the opportunity to incorporate concatenated inter-species phylogenies into bacterial systematics. Recent analyses based on single housekeeping genes have provided coherent phylogenies of Aeromonas. However, to date, a multi-gene phylogenetic analysis has never been tackled. In the present study, the intra- and inter-species phylogenetic relationships of 115 strains representing all Aeromonas species described to date were investigated by MLPA. The study included the independent analysis of seven single gene fragments (gyrB, rpoD, recA, dnaJ, gyrA, dnaX, and atpD), and the tree resulting from the concatenated 4705 bp sequence. The phylogenies obtained were consistent with each other, and clustering agreed with the Aeromonas taxonomy recognized to date. The highest clustering robustness was found for the concatenated tree (i.e. all Aeromonas species split into 100% bootstrap clusters). Both possible chronometric distortions and poor resolution encountered when using single-gene analysis were buffered in the concatenated MLPA tree. However, reliable phylogenetic species delineation required an MLPA including several "bona fide" strains representing all described species.

  10. Topological Censorship and Higher Genus Black Holes

    CERN Document Server

    Galloway, G J; Witt, D M; Woolgar, E

    1999-01-01

    Motivated by recent interest in black holes whose asymptotic geometry approaches that of anti-de Sitter spacetime, we give a proof of topological censorship applicable to spacetimes with such asymptotic behavior. Employing a useful rephrasing of topological censorship as a property of homotopies of arbitrary loops, we then explore the consequences of topological censorship for horizon topology of black holes. We find that the genera of horizons are controlled by the genus of the space at infinity. Our results make it clear that there is no conflict between topological censorship and the non-spherical horizon topologies of locally anti-de Sitter black holes. More specifically, let D be the domain of outer communications of a boundary at infinity ``scri.'' We show that the principle of topological censorship (PTC), that every causal curve in D having endpoints on scri can be deformed to scri, holds under reasonable conditions for timelike scri, as it is known to do for a simply connected null scri. We then show...

  11. THE GENUS VIBURNUM (CAPRIFOLIACEAE IN MALAYSIA

    Directory of Open Access Journals (Sweden)

    J. H. KERN

    2015-11-01

    Full Text Available 1. In the following pages an account of the genus Viburnum in Malaysia is presented. 2. The distribution of its species is briefly discussed and a map relating to it added. 3. The main part of the present paper consists of keys to the sections and species, followed by a systematic treatment of the 16 species admitted for the region. 4. Three new subsections are proposed, viz. Viburnum subsect. Punctata Kern, subsect. Sambucina Kern, and subsect. Lutescentia Kern. Viburnum subseries Coriacea Maxim, is reduced to the rank of a subsection. 5. Three species and two varieties are described as new, viz. Viburnum ampli- ficatum Kern, V. clemensae Kern, V. hispidulum Kern, V. coriaceum, var. longiflorutn Kern, and V. sambucinum var. subglabrum Kern. 6. The following species are reduced to the rank of varieties: Viburnum flori- bundum Merr. has become V. luzonicum var. floribundum (Merr. Kern, and V. sinu- atum Merr. has become V. luzonicum var. sinuatum (Merr. Kern. 7. The following reductions'to synonymy are made: Viburnum longistamineum Ridl. to V. sambucinum- var. subglabrum Kern; V. sumatranum Miq., V.villosum Ridl., and V. inopinatum Craib all to V. sambucinum var. tovientosum Hallier f.; V. forbesii Fawc. partly to V. sambucimim Bl., partly to V. coriaceum BL; and V. zippelii Miq. to V. japonicum (Thunb. Spr. 8. Emended descriptions of Viburnum beccarii Gamble and of V. junghuhnii Miq. are given.

  12. Functional proteomics within the genus Lactobacillus.

    Science.gov (United States)

    De Angelis, Maria; Calasso, Maria; Cavallo, Noemi; Di Cagno, Raffaella; Gobbetti, Marco

    2016-03-01

    Lactobacillus are mainly used for the manufacture of fermented dairy, sourdough, meat, and vegetable foods or used as probiotics. Under optimal processing conditions, Lactobacillus strains contribute to food functionality through their enzyme portfolio and the release of metabolites. An extensive genomic diversity analysis was conducted to elucidate the core features of the genus Lactobacillus, and to provide a better comprehension of niche adaptation of the strains. However, proteomics is an indispensable "omics" science to elucidate the proteome diversity, and the mechanisms of regulation and adaptation of Lactobacillus strains. This review focuses on the novel and comprehensive knowledge of functional proteomics and metaproteomics of Lactobacillus species. A large list of proteomic case studies of different Lactobacillus species is provided to illustrate the adaptability of the main metabolic pathways (e.g., carbohydrate transport and metabolism, pyruvate metabolism, proteolytic system, amino acid metabolism, and protein synthesis) to various life conditions. These investigations have highlighted that lactobacilli modulate the level of a complex panel of proteins to growth/survive in different ecological niches. In addition to the general regulation and stress response, specific metabolic pathways can be switched on and off, modifying the behavior of the strains.

  13. [Advances of chemical constituents and pharmacological activities of Myristica genus].

    Science.gov (United States)

    Zhang, Yong; Zhang, Juan-Juan; Kang, Wen-Yi; Yan, Wen-Yi

    2014-07-01

    The genus Myristica (Myristicaceae) consists of 120 species, which were distributed in South Asia, from west Polynesia, Oceania, eastern India to the Philippines. Phytochemical studies showed that 164 compounds including a majority of lignans, along with phenglpropanoids, flavonoids and phenolics, have been isolated from this genus, which exhibited anti-microbial, anti-inflammatory, anticancer, hyperglycemic and hepatic protective activities. This article summarizes research progress of the chemical compositions and their pharmacological activities from this genus, which could provide reference for the in-depth development and utilization of the Myristica plants.

  14. Isleria, a new genus of antwren (Aves: Passeriformes: Thamnophilidae)

    Science.gov (United States)

    Bravo, Gustavo A.; Chesser, R. Terry; Brumfield, Robb T.

    2012-01-01

    A comprehensive molecular phylogenetic analysis of the family Thamnophilidae indicated that the genus Myrmotherula is not monophyletic. The clade composed of M. guttata and M. hauxwelli is only distantly related to other members of the genus and should be removed from Myrmotherula. The phenotypic distinctiveness of the clade argues against merging it with its sister group Thamnomanes and no generic name is available for the guttata-hauxwelli clade. Consequently, we describe the genus Isleria for these two species, and designate Myrmothera guttata as its type species.

  15. The genus Plectranthus in India and its chemistry.

    Science.gov (United States)

    Waldia, Shobha; Joshi, Bipin C; Pathak, Uma; Joshi, Mukesh C

    2011-02-01

    Phytochemical constituents isolated from Indian species of the genus Plectranthus reported up to 2009 are compiled. In India, the genus Plectranthus is found in all the habitats and altitudes, particularly in the Himalaya, the Southern Ghats, and the Nilgiri region. P. amboinicus, P. barbatus, P. caninus, P. mollis, P. coetsa, and P. incanus are the most common species found in India. Phytochemical studies of the genus revealed that Indian Plectranthus species are rich in essential oil, and that the most abundant secondary metabolites are diterpenoids, i.e., labdanes, abietanes, and ent-kauranes, as well as triterpenoids.

  16. toward a phylogeny of the kukri snakes, genus oligodon

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    the south and southeast asian snake genus oligodon,known for its egg-eating feeding behavior,has been a taxonomically and systematically challenging group.this work provides the first phylogenetic hypothesis for the genus.we use approximately 1900 base pairs of mitochondrial dna sequence data to infer the relationships of these snakes,and we examine congruence between the phylogeny and hemipenial characters.a hypothesis for the position of oligodon within the colubridae is also proposed.we discuss the implications of the phylogeny for previous taxonomic groupings,and consider the usefulness of the trees in analysis of behavior and biogeography of this genus.

  17. Bioactive phytoconstituents and plant extracts from genus Heliotropium

    Directory of Open Access Journals (Sweden)

    Naveen Goyal

    2014-01-01

    Full Text Available Heliotropium is a genus of herbs and rarely shrubs of family Boraginaceae. Heliotropium species have been used in folk medicine for the treatment of gout, rheumatism and as antiseptic, febrifuge, cholagogue, anti-inflammatory and healing agents. The alkaloids mainly pyrrolizidine alkaloids are the main constituents of Heliotropium species, which are responsible for several biological activities viz. anti-tumoural, anti-microbial, and anti-viral effects. Phenolic compounds, terpenoids, and quinones have also been reported in this genus. The present review summarizes the various biological studies done on the extracts and bioactive phytoconstituents from the plants of the genus Heliotropium over the past few decades.

  18. A revision of the genus Mecistostethus Marseul (Histeridae, Histerinae, Exosternini

    Directory of Open Access Journals (Sweden)

    Michael Caterino

    2012-08-01

    Full Text Available We revise the genus Mecistostethus Marseul, sinking the monotypic genus Tarsilister Bruch as a junior synonym. Mecistostethus contains six valid species: M. pilifer Marseul, M. loretoensis (Bruch, comb. n., M. seagorum sp. n., M. carltoni sp. n., M. marseuli sp. n., and M. flechtmanni sp. n. The few existing records show the genus to be widespread in tropical and subtropical South America, from northern Argentina to western Amazonian Ecuador and French Guiana. Only a single host record associates one species with the ant Pachycondyla striata Smith (Formicidae: Ponerinae, but it is possible that related ants host all the species.

  19. Systematic Review of Chemical Constituents in the Genus Lycium (Solanaceae

    Directory of Open Access Journals (Sweden)

    Dan Qian

    2017-06-01

    Full Text Available The Lycium genus is widely used as a traditional Chinese medicine and functional food. Many of the chemical constituents of the genus Lycium were reported previously. In this review, in addition to the polysaccharides, we have enumerated 355 chemical constituents and nutrients, including 22 glycerogalactolipids, 29 phenylpropanoids, 10 coumarins, 13 lignans, 32 flavonoids, 37 amides, 72 alkaloids, four anthraquinones, 32 organic acids, 39 terpenoids, 57 sterols, steroids, and their derivatives, five peptides and three other constituents. This comprehensive study could lay the foundation for further research on the Lycium genus.

  20. Anangia, a new monotypic genus of Cucurbitaceae from East Moluccas

    Directory of Open Access Journals (Sweden)

    W.J.J.O. De Wilde

    2006-12-01

    Full Text Available DE WILDE, W.J.J.O; DUYFEES, B.E.E. & VAN DER HAM, R.W.J.M. 2006. Anangia, a new monotypic genus of Cucurbitaceae from East Moluccas. Reinwardtia 12(3: 219 – 222.– A new monotypic genus of Cucurbitaceae from Morotai (Indonesia is described. The genus is defined by unique characters, including large sepals, much longer than the petals, and it has distinctly cucurbitoid pollen features. The only species is Anangia macrosepala W.J. de Wilde & Duyfjes. 

  1. Anangia, a new monotypic genus of Cucurbitaceae from East Moluccas

    OpenAIRE

    W.J.J.O. De Wilde; Brigitta E. E. Duyfjes; RWJM Van Der Ham

    2006-01-01

    DE WILDE, W.J.J.O; DUYFEES, B.E.E. & VAN DER HAM, R.W.J.M. 2006. Anangia, a new monotypic genus of Cucurbitaceae from East Moluccas. Reinwardtia 12(3): 219 – 222.– A new monotypic genus of Cucurbitaceae from Morotai (Indonesia) is described. The genus is defined by unique characters, including large sepals, much longer than the petals, and it has distinctly cucurbitoid pollen features. The only species is Anangia macrosepala W.J. de Wilde & Duyfjes. 

  2. Diversity of secondary metabolites from Genus Artocarpus (Moraceae

    Directory of Open Access Journals (Sweden)

    ALIEFMAN HAKIM

    2010-11-01

    Full Text Available Hakim A. 2010. The diversity of secondary metabolites from Genus Artocarpus (Moraceae. Nusantara Bioscience 2:146-156. Several species of the Artocarpus genus (Moraceae have been investigated their natural product. The secondary metabolites successfully being isolatad from Artocarpus genus consist of terpenoid, flavonoids, stilbenoid, arylbenzofuran, neolignan, and adduct Diels-Alder. Flavonoid group represent the compound which is the most found from Artocarpus plant. The flavonoids compound which are successfully isolated from Artocarpus plant consist of the varied frameworks like chalcone, flavanone, flavan-3-ol, simple flavone, prenylflavone, oxepinoflavone, pyranoflavone, dihydrobenzoxanthone, furanodihydrobenzoxanthone, pyranodihydrobenzoxanthone, quinonoxanthone, cyclopentenoxanthone, xanthonolide, dihydroxanthone.

  3. Identity of Baker's species described in the Oriental leafhopper genus Pythamus (Hemiptera: Cicadellidae) with description of a new genus.

    Science.gov (United States)

    Wei, Cong; Webb, Michael D; Zhang, Yalin

    2014-01-01

    Baker's (1915) species described in the Oriental leafhopper genus Pythamus Melichar are revised. One species, Pythamus melichari Baker 1915, is placed in a new genus, Pythochandra Wei & Webb, gen. n.. The four varieties of P. melichari described by Baker (1915, 1923) (borneensis, bilobatus, decoratus and singaporensis) are elevated to species level and placed in the new genus stat. n., comb. n.. All species are briefly described and a key is provided for their separation. Two other species, Pythamus productus Baker and P. decoratus Baker, known only from females, are retained in Pythamus pending further studies.

  4. Quaternion Algebras over Curves of Genus One Without Rational Points

    Institute of Scientific and Technical Information of China (English)

    Susanne Pumpl(u)n

    2005-01-01

    Quaternion algebras over curves of genus one without rational points over perfect fields of characteristic not two are classified. As a consequence, all quaternion algebras over the function field of such a curve, which are unramified everywhere, are classified.

  5. Some adaptational peculiarities of introduced species of the genus Hydrangea

    Directory of Open Access Journals (Sweden)

    V. N. Kuchma

    2006-03-01

    Full Text Available Among studied the Hydrangea L. genus the species, which most adapted to the environment of steppe conditions, were developed. H. cinerea Stall. and H. bretschneider Dipp. are recommended for use in laying out of parks, etc.

  6. A new genus of Smiliini (Hemiptera: Membracidae) from Costa Rica

    Science.gov (United States)

    A new genus and species, Smilirhexia naranja, is described from Costa Rica, the southern limit of the tribe Smiliini, and represents a strong divergence from the morphology of the oak-feeding genera prevalent in North America....

  7. Karyotype evolution and species differentiation in the genus Rattus ...

    African Journals Online (AJOL)

    Dhananjoy

    Karyotype evolution and species differentiation in the genus Rattus of ... as primitive/ancestral types of chromosomes into either subtelocentric or small metacentrics leads to speciation or simply new ..... The features are quite common in the.

  8. Occurrence of genus Monostroma (Ulvales, Chlorophyta) from Ratnagiri (Maharashtra)

    Digital Repository Service at National Institute of Oceanography (India)

    Untawale, A.G.; Agadi, V.V.; Dhargalkar, V.K.

    The occurrence of a genus Monostroma has been recorded from the Shirgaon creek at Ratnagiri along the central west coast of India. The Monostroma sp. was found in the brackish water environment with low salinity, high nutrients and thick mangrove...

  9. Some enigmatic aspects of the marine cyanobacterial genus, Trichodesmium

    Digital Repository Service at National Institute of Oceanography (India)

    Bhat, S.R.; Verlecar, X.N.

    Trichodesmium, an important nitrogen fixing marine genus has some coupled features that appear contrasting, either in their operational requirements or ecological dominance e.g. N2 fixation and photosynthesis take place in the same trichome, former...

  10. A new Neotropical genus of Blastini (Psocodea: 'Psocoptera': Psocidae: Amphigerontiinae).

    Science.gov (United States)

    Aldrete, Alfonso N García; Román-P, Cristian

    2015-08-17

    A monotypic genus of Psocidae (Amphigerontiinae: Blastini) from Santiago de Cali, Colombia, is here described and illustrated. It differs from Chaetopsocidus Badonnel, from the Páramo de Monserrate, near Bogotá, in having setae on the forewing veins.

  11. A review on phytochemistry and ethnopharmacological aspects of genus Calendula.

    Science.gov (United States)

    Arora, Disha; Rani, Anita; Sharma, Anupam

    2013-07-01

    This review includes 84 references on the genus Calendula (Asteraceae) and comprises ethnopharmacology, morphology and microscopy, phytoconstituents, pharmacological reports, clinical studies and toxicology of the prominent species of Calendula. Triterpene alcohols, triterpene saponins, flavonoids, carotenoids and polysaccharides constitute major classes of phytoconstituents of the genus. A few species of this genus have medicinal value, among these Calendula officinalis Linn., has been traditionally used in the treatment of various skin tumors, dermatological lesions, ulcers, swellings and nervous disorders as well as almost 200 cosmetic formulations, i.e., creams, lotions, shampoos. Despite a long tradition of use of some species, the genus has not been explored properly. In the concluding part, the future scope of Calendula species has been emphasized with a view to establish their multifarious biological activities and mode of action.

  12. Notes on genus Eurydoxa Filipjev (Lepidoptera: Tortricidae) in China

    Institute of Scientific and Technical Information of China (English)

    BYUN Bong-Kyu; YAN Shan-chun; LI Cheng-de

    2003-01-01

    Genus Eurydoxa Filipjev in China is reviewed and noted for the first time. Based on the present study, two species are recognized, including rhodopa Diakonoff and advena Filipjev. All available information for the species is reviewed and provided.

  13. Is Stringaspidiotus Macgillivray (Hemiptera: Coccoidea: Diaspididae) An Accepted Genus?

    Science.gov (United States)

    The genus Stringaspidiotus MacGillivray, 1921 is synonymized with Pseudaonidia Cockerell, 1897 as a junior subjective synonym and the type species of Stringaspidiotus (Aspidiotus (Pseudaonidia) curculiginis) is redescribed and illustrated....

  14. Contribution to the genus Xanthocorus Miyatake (Coleoptera, Coccinellidae, Chilocorini).

    Science.gov (United States)

    Li, Wenjing; Chen, Xiaosheng; Wang, Xingmin; Ren, Shunxiang

    2015-01-01

    The genus Xanthocorus Miyatake, 1970 consists of three species from China, including two new species described here: Xanthocorusnigrosuturalis sp. n. and Xanthocorusmucronatus sp. n. A key to identification of species is given. Diagnoses, detailed descriptions, illustrations, and distributions are provided.

  15. Comparative Genomics Reveals High Genomic Diversity in the Genus Photobacterium

    DEFF Research Database (Denmark)

    Machado, Henrique; Gram, Lone

    2017-01-01

    Vibrionaceae is a large marine bacterial family, which can constitute up to 50% of the prokaryotic population in marine waters. Photobacterium is the second largest genus in the family and we used comparative genomics on 35 strains representing 16 of the 28 species described so far, to understand...... the genomic diversity present in the Photobacterium genus. Such understanding is important for ecophysiology studies of the genus. We used whole genome sequences to evaluate phylogenetic relationships using several analyses (16S rRNA, MLSA, fur, amino-acid usage, ANI), which allowed us to identify two...... misidentified strains. Genome analyses also revealed occurrence of higher and lower GC content clades, correlating with phylogenetic clusters. Pan-and core-genome analysis revealed the conservation of 25% of the genome throughout the genus, with a large and open pan-genome. The major source of genomic diversity...

  16. Quadratic differentials in low genus: exceptional and non-varying

    CERN Document Server

    Chen, Dawei

    2012-01-01

    We give an algebraic way of distinguishing the components of the exceptional strata of quadratic differentials in genus three and four. The complete list of these strata is (9, -1), (6,3,-1), (3,3,3, -1) in genus three and (12), (9,3), (6,6), (6,3,3) and (3,3,3,3) in genus four. This result is part of a more general investigation of disjointness of Teichmueller curves with divisors of Brill-Noether type on the moduli space of curves. As a result we show that for many strata of quadratic differentials in low genus the sum of Lyapunov exponents for the Teichmueller geodesic flow is the same for all Teichmueller curves in that stratum.

  17. Description of a new species of the Rhynchophorous genus Oxyrhynchus

    NARCIS (Netherlands)

    Roelofs, W.

    1880-01-01

    Elongatus, fuliginosus, opacus, fossulis luteo-pulverosis sparsutus. Sutura alba, prothoracis basi atomis albis adspersa. — Long. 10 mm. rostr. excl. Of a narrower shape than the other known species of the genus.

  18. The second pluri-genus of smoothable Gorenstein surface singularities

    Institute of Scientific and Technical Information of China (English)

    YAU; Stephen; S.; T.

    2010-01-01

    For complete intersection isolated surface singularities, Okuma gave a formula for the second plurigenus relating geometry genus, Milnor number and Tjurina number. We generalize Okuma’s theorem to Gorenstein smoothable surface singularities.

  19. Two New Treehoppers of the Genus Sipylus (Homoptera, Membracidae)

    OpenAIRE

    Masami, HAYASHI; Toshitsugu, ENDO; Department of Biology, Faculty of Education, Saitama University

    1990-01-01

    Two new species of the genus Sipylus, sphyrna and piceus, are described from North Thailand and the Malay Peninsula, respectively. Some remarks on the species are given in comparison with S. truncaticornis FUNKHOUSER and auriculatus FUNKHOUSER.

  20. Higher genus correlators from the hermitian one-matrix model

    Energy Technology Data Exchange (ETDEWEB)

    Ambjoern, J. (Niels Bohr Inst., Copenhagen (Denmark)); Chekhov, L. (Steklov Mathematical Inst., Moscow (Russia)); Makeenko, Yu. (Inst. of Theoretical and Experimental Physics, Moscow (Russia))

    1992-05-28

    We develop an iterative algorithm for the genus expansion of the hermitian NxN one-matrix model (is the Penner model in an external field). By introducing moments of the external field, we prove that the genus g contribution to the m-loop correlator depends only on 3g-2+m lower moments (3g-2 for the partition function). We present the explicit results for the partition function and the one-loop correlator in genus one. We compare the correlators for the hermitian one-matrix model with those at zero momenta for c=1 CFT and show an agreement of the one-loop correlators for genus zero. (orig.).

  1. Warionia (Asteraceae: a relict genus of Cichorieae?

    Directory of Open Access Journals (Sweden)

    Katinas, Liliana

    2008-12-01

    Full Text Available The genus Warionia, with its only species W. saharae, is endemic to the northwestern edge of the African Sahara desert. This is a somewhat thistle-like aromatic plant, with white latex, and fleshy, pinnately- partite leaves. Warionia is in many respects so different from any other genus of Asteraceae, that it has been tentatively placed in the tribes Cardueae, Cichorieae, Gundelieae, and Mutisieae. Until now, a comprehensive study of Warionia to have a complete context for discussing its taxonomic position is lacking. The general morphology, anatomy, palynology and chromosome number of W. saharae are investigated here, and the species is described and illustrated. Laticifers in leaves and stems indicate a relationship with Cichorieae, and are associated with the phloem, in contact with it or with the surrounding sclerenchyma sheath. The pollen features indicate a strong relation with Cardueae, namely the structure with Anthemoid pattern where the columellae are joined to the foot layer, the ectosexine with thin columellae, the endosexine with stout and ramified columellae, the conspicuous spines with globose bases and conspicuous apical channels, and the tectum surface very perforate. Chromosomal counts resulted in 2n = 34. The morphological and palynological evidence positions Warionia between the tribes Cardueae and Cichorieae suggesting that it could be a remnant of the ancestral stock that gave rise to both tribes.El género Warionia, y su única especie, W. saharae, es endémico del noroeste del desierto africano del Sahara. Es una planta semejante a un cardo, aromática, con látex blanco y hojas carnosas, pinnatipartidas. Warionia es tan diferente de otros géneros de Asteraceae que fue ubicada en las tribus Cardueae, Cichorieae, Gundelieae y Mutisieae. Hasta ahora, no existía un estudio global de Warionia como contexto para discutir su posición taxonómica. Se ha investigado aquí su morfología, anatomía, palinología y n

  2. Epigenomic diversification within the genus Lupinus

    Science.gov (United States)

    Bewick, Adam J.; Hasterok, Robert; Schmitz, Robert J.; Naganowska, Barbara

    2017-01-01

    Deciphering the various chemical modifications of both DNA and the histone compound of chromatin not only leads to a better understanding of the genome-wide organisation of epigenetic landmarks and their impact on gene expression but may also provide some insights into the evolutionary processes. Although both histone modifications and DNA methylation have been widely investigated in various plant genomes, here we present the first study for the genus Lupinus. Lupins, which are members of grain legumes (pulses), are beneficial for food security, nutrition, health and the environment. In order to gain a better understanding of the epigenetic organisation of genomes in lupins we applied the immunostaining of methylated histone H3 and DNA methylation as well as whole-genome bisulfite sequencing. We revealed variations in the patterns of chromatin modifications at the chromosomal level among three crop lupins, i.e. L. angustifolius (2n = 40), L. albus (2n = 50) and L. luteus (2n = 52), and the legume model plant Medicago truncatula (2n = 16). Different chromosomal patterns were found depending on the specific modification, e.g. H3K4me2 was localised in the terminal parts of L. angustifolius and M. truncatula chromosomes, which is in agreement with the results that have been obtained for other species. Interestingly, in L. albus and L. luteus this modification was limited to one arm in the case of all of the chromosomes in the complement. Additionally, H3K9me2 was detected in all of the analysed species except L. luteus. DNA methylation sequencing (CG, CHG and CHH contexts) of aforementioned crop but also wild lupins such as L. cosentinii (2n = 32), L. digitatus (2n = 36), L. micranthus (2n = 52) and L. pilosus (2n = 42) supported the range of interspecific diversity. The examples of epigenetic modifications illustrate the diversity of lupin genomes and could be helpful for elucidating further epigenetic changes in the evolution of the lupin genome. PMID:28640886

  3. The Genus Asparagus in Southern Africa*

    Directory of Open Access Journals (Sweden)

    J. P. Jessop

    1966-12-01

    Full Text Available A revision of the genus Asparagus in South Africa, South West Africa, Bechuanaland, Basutoland, and Swaziland has been undertaken. Notes are given on the value of most o f the characters which have been used in the separation of species, recent literature on the nature of  Asparagus assimilatory organs, and a technique for the examination of chromosomes. Chromosome counts are listed for ten taxa. There is a key to the forty species and four varieties. In the main part of the work these taxa are described, and their synonymy, taxonomy, distribution and habitats dealt with. Six species and one variety are new. The following are the new species and combinations:  A. setaceus (Kunth (Asparagopsis setacea Kunth, A. mueronatus, A. macowanii Bak. var. zuluensis (N. E. Br.  (A. zuluensis N. E. Br., A. rigidus, A. densiflorus (Kunth  {Asparagopsis densiflora Kunth,  A. aethiopicus L. var. angusticladus, A. falcatus L. var. ternifolius (Bak.  (A. aethiopicus L. var.  ternifolius Bak.,  A. aspergillus,  A. obermeyerae,  A. krebsianus (Kunth (Asparagopsis krebsiana Kunth,  A. acocksii.  A. crassicladus. Several plants o f horticultural importance occur in South Africa. The three best known are A. plumosus, which is reduced here to synonymy under  A. setaceus (Kunth Jessop, and  A. sprengeri and  A. myersii. A. sprengeri is being reduced to synonymy under  A. densiflorus (Kunth Jessop,.  A. myersii, which is a  nomen nudum, is also regarded as belonging to  A. densiflorus.

  4. The Genus Asparagus in Southern Africa*

    Directory of Open Access Journals (Sweden)

    J. P. Jessop

    1966-12-01

    Full Text Available A revision of the genus Asparagus in South Africa, South West Africa, Bechuanaland, Basutoland, and Swaziland has been undertaken. Notes are given on the value of most o f the characters which have been used in the separation of species, recent literature on the nature of  Asparagus assimilatory organs, and a technique for the examination of chromosomes. Chromosome counts are listed for ten taxa. There is a key to the forty species and four varieties. In the main part of the work these taxa are described, and their synonymy, taxonomy, distribution and habitats dealt with. Six species and one variety are new. The following are the new species and combinations:  A. setaceus (Kunth (Asparagopsis setacea Kunth, A. mueronatus, A. macowanii Bak. var. zuluensis (N. E. Br.  (A. zuluensis N. E. Br., A. rigidus, A. densiflorus (Kunth  {Asparagopsis densiflora Kunth,  A. aethiopicus L. var. angusticladus, A. falcatus L. var. ternifolius (Bak.  (A. aethiopicus L. var.  ternifolius Bak.,  A. aspergillus,  A. obermeyerae,  A. krebsianus (Kunth (Asparagopsis krebsiana Kunth,  A. acocksii.  A. crassicladus. Several plants o f horticultural importance occur in South Africa. The three best known are A. plumosus, which is reduced here to synonymy under  A. setaceus (Kunth Jessop, and  A. sprengeri and  A. myersii. A. sprengeri is being reduced to synonymy under  A. densiflorus (Kunth Jessop,.  A. myersii, which is a  nomen nudum, is also regarded as belonging to  A. densiflorus.

  5. The genus Allium--Part 3.

    Science.gov (United States)

    Fenwick, G R; Hanley, A B

    1985-01-01

    Allium is a genus of some 500 species belonging to the family Liliaceae. However, only a few of these are important as food plants, notably onion, garlic, chive, leek, and rakkyo. Such plants have been used for many centuries for their pungency and flavoring value, for their medicinal properties, and in some parts of the world, their use also has religious connotations. The flavors of members of alliums, in addition to being characteristic, are also complex, being derived enzymically from a number of involatile precursors. As well as there being variation of flavor between different alliums there are also considerable changes that occur as a result of cooking and processing. These are, of course, of importance to the consumer and food technologist/processor. The review will introduce the subject by an historical perspective and will set against this data on the present cultivation and usage of commercially cultivated alliums. The chemical composition of these plants will be discussed, emphasis being given to nonvolatile constituents which are, perhaps, less often considered. Discussion of the volatile constituents, which will include mention of the methods currently used for their analysis and for the determination of "flavor strength," will be mainly concerned with literature taken from the last 5 years. In considering the extent and nature of allium cultivation and processing, factors affecting the nutritional value and quality will be highlighted. The medicinal properties of garlic and onion oils have been extensively studied over the last decade and the review will include critical assessment of this area; it will also touch on the more general properties (antimicrobial, antifungal, antibacterial, and insecticidal) of these oils. Finally, mention will be made of the antinutritional, toxic, or otherwise undesirable effects of alliums, for example, as inadvertant components of animal diets, tainting of milk, and other food products. It is our intention to review

  6. Chemical and pharmacological studies of the plants from genus Celastrus.

    Science.gov (United States)

    Su, Xiao-Hui; Zhang, Man-Li; Zhan, Wen-Hong; Huo, Chang-Hong; Shi, Qing-Wen; Gu, Yu-Cheng; Kiyota, Hiromasa

    2009-02-01

    The plants of genus Celastrus, distributed in Asia, have been used as natural insecticides and folk medicines to treat fever, chill, joint pain, edema, rheumatoid arthritis, and bacterial infection in China for a long time. This contribution reviews the chemical constituents, isolated from the plants in genus Celastrus in the past few decades, and their biological activities. The compounds listed are sesquiterpenes (beta-agarofurans), diterpenes, triterpenes, alkaloids, and flavonoids.

  7. Morphometrics of genus Caluromys (Didelphimorphia : Didelphidae) in northern South America

    OpenAIRE

    López Fuster, María José; Pérez Hernández, Roger; Ventura Queija, Jacinto

    2008-01-01

    We reviewed the morphometric relationships between different forms of the woolly opossum, genus Caluromys, in northern South America by means of univariate and multivariate analyses of skull characters. Results revealed that specimens from Trinidad and northern Venezuela differ substantially in size and shape from other representatives of the genus. Thus, we propose that they should be attributed to Caluromys trinitatis rather to C. philander. Consequently, the specific name given by Thomas (...

  8. Revision of the genus Trypeticus Marseul (Coleoptera: Histeridae)

    OpenAIRE

    Kanaar, P.

    2003-01-01

    The genus Trypeticus Marseul, 1864 is revised and figured. A key to the species is given. Redescriptions of the hitherto described species are presented. The number of species in this genus has been brought up to 100, of which 72 species are described as new: T. adebratti (Sabah, Brunei), T. alticola (Indonesia: Irian Jaya), T. angustifrons (Indonesia: Irian Jaya?), T. arriagadai (Philippines), T. aukei (W. Malaysia, Sabah), T. bertiae (India), T. boukei (Sabah), T. brevis (Sabah), T. capilla...

  9. Torsionfree Sheaves over a Nodal Curve of Arithmetic Genus One

    Indian Academy of Sciences (India)

    Usha N Bhosle; Indranil Biswas

    2008-02-01

    We classify all isomorphism classes of stable torsionfree sheaves on an irreducible nodal curve of arithmetic genus one defined over $\\mathbb{C}$. Let be a nodal curve of arithmetic genus one defined over $\\mathbb{R}$, with exactly one node, such that does not have any real points apart from the node. We classify all isomorphism classes of stable real algebraic torsionfree sheaves over of even rank. We also classify all isomorphism classes of real algebraic torsionfree sheaves over of rank one.

  10. Bounds for Siegel Modular Forms of genus 2 modulo $p$

    CERN Document Server

    Choi, Dohoon; Kikuta, Toshiyuki

    2011-01-01

    Sturm obtained the bounds for the number of the first Fourier coefficients of elliptic modular form $f$ to determine vanishing of $f$ modulo a prime $p$. In this paper, we study analogues of Sturm's bound for Siegel modular forms of genus 2. We show the resulting bound is sharp. As an application, we study congruences involving Atkin's $U(p)$-operator for the Fourier coefficients of Siegel mdoular forms of genus 2.

  11. Higher Genus Abelian Functions Associated with Cyclic Trigonal Curves

    Directory of Open Access Journals (Sweden)

    Matthew England

    2010-03-01

    Full Text Available We develop the theory of Abelian functions associated with cyclic trigonal curves by considering two new cases. We investigate curves of genus six and seven and consider whether it is the trigonal nature or the genus which dictates certain areas of the theory. We present solutions to the Jacobi inversion problem, sets of relations between the Abelian function, links to the Boussinesq equation and a new addition formula.

  12. Evidence for ecological flexibility in the cosmopolitan genus Curtobacterium

    OpenAIRE

    Alexander Bennett Chase; Philip Arevalo; Polz, Martin F.; Renaud Berlemont; Martiny, Jennifer B H

    2016-01-01

    Assigning ecological roles to bacterial taxa remains imperative to understanding how microbial communities will respond to changing environmental conditions. Here we analyze the genus Curtobacterium as it was found to be the most abundant taxon in a leaf litter community in southern California. Traditional characterization of this taxon predominantly associates it as the causal pathogen in the agricultural crops of dry beans. Therefore, we seek to conduct a broad investigation into this genus...

  13. Revision of the genus Trypeticus Marseul (Coleoptera: Histeridae)

    OpenAIRE

    Kanaar, P.

    2003-01-01

    The genus Trypeticus Marseul, 1864 is revised and figured. A key to the species is given. Redescriptions of the hitherto described species are presented. The number of species in this genus has been brought up to 100, of which 72 species are described as new: T. adebratti (Sabah, Brunei), T. alticola (Indonesia: Irian Jaya), T. angustifrons (Indonesia: Irian Jaya?), T. arriagadai (Philippines), T. aukei (W. Malaysia, Sabah), T. bertiae (India), T. boukei (Sabah), T. brevis (Sabah), T. capilla...

  14. A new genus Mesophlaeoba (Orthoptera: Acrididae: Acridinae from India

    Directory of Open Access Journals (Sweden)

    H. Kumar

    2015-04-01

    Full Text Available A new genus of Acridinae, Mesophlaeoba Kumar and Usmani gen. n. based on type species Mesophlaeoba usmanii Kumar and Usmani sp. n., is described and illustrated from India. The description was based on both conventional morphological and genital characters. The new genus is closely related to Phlaeoba Stal, 1861 but differs from it in presence of filiform antennae, absence of median carinula of fastigium of vertex and rounded posterior margin of pronotum.

  15. Phylogenomic re-assessment of the thermophilic genus Geobacillus.

    Science.gov (United States)

    Aliyu, Habibu; Lebre, Pedro; Blom, Jochen; Cowan, Don; De Maayer, Pieter

    2016-12-01

    Geobacillus is a genus of Gram-positive, aerobic, spore-forming obligate thermophiles. The descriptions and subsequent affiliations of the species in the genus have mostly been based on polyphasic taxonomy rules that include traditional sequence-based methods such as DNA-DNA hybridization and comparison of 16S rRNA gene sequences. Currently, there are fifteen validly described species within the genus. The availability of whole genome sequences has provided an opportunity to validate and/or re-assess these conventional estimates of genome relatedness. We have applied whole genome approaches to estimate the phylogenetic relatedness among the sixty-three Geobacillus strains for which genome sequences are currently publicly available, including the type strains of eleven validly described species. The phylogenomic metrics AAI (Average Amino acid Identity), ANI (Average Nucleotide Identity) and dDDH (digital DNA-DNA hybridization) indicated that the current genus Geobacillus is comprised of sixteen distinct genomospecies, including several potentially novel species. Furthermore, a phylogeny constructed on the basis of the core genes identified from the whole genome analyses indicated that the genus clusters into two monophyletic clades that clearly differ in terms of nucleotide base composition. The G+C content ranges for clade I and II were 48.8-53.1% and 42.1-44.4%, respectively. We therefore suggest that the Geobacillus species currently residing within clade II be considered as a new genus. Copyright © 2016 Elsevier GmbH. All rights reserved.

  16. Genus identification of toxic plant by real-time PCR.

    Science.gov (United States)

    Matsuyama, Shuji; Nishi, Katsuji

    2011-03-01

    Some plants have toxicities that are dangerous for humans. In the case of poisoning by toxic plants, a rapid and easy screening test is required for accurate medical treatment or forensic investigation. In this study, we designed specific primer pairs for identification of toxic plants, such as subgenus Aconitum, genus Ricinus, genus Illicium, and genus Scopolia, by internal transcribed spacer sequences of nuclear ribosomal DNA. Allied species of target plants, foods, and human DNA were not detected, but each primer pair provided a specific PCR product from the target plant using real-time PCR. This method can detect the subgenus Aconitum, genus Ricinus, and genus Scopolia with template DNA of 10 pg, respectively, and genus Illicium with 1 pg. Furthermore, each primer pair provided the exact PCR product from digested target plants in artificial gastric fluid. When a trace unknown plant sample in forensic investigation is collected from stomach contents, this PCR assay may be useful for screening toxic plants.

  17. Pseudolygocoris punctulatus, a New Genus and a New Species of the Miridae from Japan (Heteroptera)

    OpenAIRE

    Tomohide, YASUNAGA; Biological Laboratory, Hokkaido University of Education

    1995-01-01

    A new genus and species of the Miridae, Pseudolygocoris punctulatus, is described from Japan. This genus is characterized by the long erect hairs densely covering the dorsal surface, slender and linear antennae, distinct deep punctures on the pronotum, hairy tibiae that lack the spines and genital structure. The present new genus resembles a large Holarctic genus Lygocoris REUTER and a Nearctic Tropidosteptes UHLER.

  18. The genus Rhaponticum in East Asia

    Directory of Open Access Journals (Sweden)

    Gorovoy, P.

    2010-12-01

    Full Text Available The genus Rhaponticum in East Asia has always been a taxon for discussion. Rhaponticum carthamoides from East Siberia comprises three subspecies: carthamoides, chamarensis and orientale. Even though they differ in morphology, they do not have isolated areas. Rhaponticum satzyperovii was recently described and its author pointed out its affinity with Rh. uniflorum. Plant height, stem indumentum, and radical and stem leaf dissection were signaled as the diagnostic characters. Our present study on living and herbarium specimens of Rh. satzyperovii shows that the diagnostic characters are not consistent. The species area was also claimed to be an argument for considering Rh. satzyperovii a distinct species. This area covers the south of the Primorye Province in the Far East of Russia with some locations in the adjacent Jewish Autonomous Region and in China. In our study, the area of Rh. satzyperovii is found to be within the area of Rh. uniflorum and thereafter they turned out to have no disjunction. In East Asia, Rh. uniflorum is characterized by a wide range of morphological variability. We suggest that Rh. satzyperovii should be included within Rh. uniflorum without any taxonomic rank.El género Rhaponticum en el Este de Asia ha sido siempre un taxón discutido. Rhaponticum carthamoides del Este de Siberia incluye tres subespecies: carthamoides, chamarensis y orientale. Aunque difieren en su morfología, sus áreas no están aisladas. Rhaponticum satzyperovii fue descrito recientemente y su autor señaló su afinidad con Rh. uniflorum. Los caracteres diagnósticos fueron la altura de la planta, el indumento del tallo y las divisiones de las hojas basales y caulinares. Nuestro estudio de plantas vivas y muestras de herbario de Rh. satzyperovii muestra que los caracteres diagnósticos no son consistentes. El área de distribución también se argumentó para considerar Rh. satzyperovii una especie diferente. El área cubre el sur de la provincia de

  19. An investigation of self-incompatibility within the genus Restrepia.

    Science.gov (United States)

    Millner, Helen J; McCrea, Alison R; Baldwin, Timothy C

    2015-03-01

    • The genus Restrepia (Orchidaceae) is indigenous to montane rain forests of Central and South America. Recently, as habitat has fragmented and wild populations dwindled, the chances for successful cross-pollination within the genus have been reduced. Since cultivated species of Restrepia have been vegetatively propagated, they remain genetically close to those in the wild, making ex situ collections of the genus useful model populations for investigating breeding systems. Restrepia are found in clade B of the Pleurothallidinae, the only clade in which self-incompatibility (SI) has not yet been confirmed. In the current study, private collections of Restrepia were used to study the operation of SI within the genus to assist future ex situ conservation of this and related genera.• A variety of self-pollination, intraspecific, and interspecific crosses were performed across the genus, and pollen tube growth was studied.• Individual species exhibited varying degrees of SI. Self-pollinations performed across 26 species in the genus produced few viable seeds, with the exception of R. aberrans. Viable "filled" seeds with embryos were shown to require an intraspecific cross. Primary hybrids between species produced >90% seeds with embryos that germinated well.• The type of SI operating within the genus was considered to be best explained by gametophytic self-incompatibility (GSI) with interspecific variation in its phenotypic expression. The implications of these findings are discussed in relation to SI in the Pleurothallidinae and conservation strategies for Restrepia and related genera. © 2015 Botanical Society of America, Inc.

  20. Transfer of eleven species of the genus Burkholderia to the genus Paraburkholderia and proposal of Caballeronia gen. nov. to accommodate twelve species of the genera Burkholderia and Paraburkholderia.

    Science.gov (United States)

    Dobritsa, Anatoly P; Samadpour, Mansour

    2016-08-01

    It has been proposed to split the genus Burkholderia into two genera according to phylogenetic clustering: (1) a genus retaining this name and consisting mainly of animal and plant pathogens and (2) the genus Paraburkholderia including so-called environmental bacteria. The latter genus name has been validly published recently. During the period between the effective and valid publications of the genus name Paraburkholderia, 16 novel species of the genus Burkholderiawere described, but only two of them can be classified as members of this genus based on the emended genus description. Analysis of traits and phylogenetic positions of the other 11 species shows that they belong to the genus Paraburkholderia, and we propose to transfer them to this genus. The reclassified species names are proposed as Paraburkholderia dipogonis comb. nov., Paraburkholderia ginsengiterrae comb. nov., Paraburkholderia humisilvae comb. nov., Paraburkholderia insulsa comb. nov., Paraburkholderia kirstenboschensis comb. nov., Paraburkholderia metalliresistens comb. nov., Paraburkholderia monticola comb. nov., Paraburkholderia panaciterrae comb. nov., Paraburkholderia rhizosphaerae comb. nov., Paraburkholderia solisilvae comb. nov. and Paraburkholderia susongensis comb. nov. The remaining three species are transferred to the new genus Caballeronia gen. nov. proposed to accommodate twelve species of the genera Burkholderia and Paraburkholderia forming a distinctive clade in phylogenetic trees. The new genus members are Caballeronia choica comb. nov., Caballeronia cordobensis comb. nov., Caballeronia glathei comb. nov., Caballeronia grimmiae comb. nov., Caballeronia humi comb. nov., Caballeronia megalochromosomata comb. nov., Caballeronia jiangsuensis comb. nov., Caballeronia sordidicola comb. nov., Caballeronia telluris comb. nov., Caballeronia terrestris comb. nov., Caballeronia udeis comb. nov., and Caballeronia zhejiangensis comb. nov.

  1. Convex-Faced Combinatorially Regular Polyhedra of Small Genus

    Directory of Open Access Journals (Sweden)

    Jörg M. Wills

    2011-12-01

    Full Text Available Combinatorially regular polyhedra are polyhedral realizations (embeddings in Euclidean 3-space E3 of regular maps on (orientable closed compact surfaces. They are close analogues of the Platonic solids. A surface of genus g ≥ 2 admits only finitely many regular maps, and generally only a small number of them can be realized as polyhedra with convex faces. When the genus g is small, meaning that g is in the historically motivated range 2 ≤ g ≤ 6, only eight regular maps of genus g are known to have polyhedral realizations, two discovered quite recently. These include spectacular convex-faced polyhedra realizing famous maps of Klein, Fricke, Dyck, and Coxeter. We provide supporting evidence that this list is complete; in other words, we strongly conjecture that in addition to those eight there are no other regular maps of genus g, with 2 ≤ g ≤ 6, admitting realizations as convex-faced polyhedra in E3. For all admissible maps in this range, save Gordan’s map of genus 4, and its dual, we rule out realizability by a polyhedron in E3.

  2. [Quantitative analysis of nucleosides in four Cordyceps genus by HPLC].

    Science.gov (United States)

    Qian, Zheng-Ming; Li, Wen-Qing; Wang, Chuan-Xi; Zhou, Miao-Xia; Sun, Min-Tian; Gao, Hao; Li, Wen-Jia

    2016-07-01

    To compare the main nucleosides in Cordyceps genus herbs (C. sinensis, C. millitaris, Hirsutella sinensis and C. sobolifera), an HPLC method for simultaneous determination of uridine, inosine, guanosine, adenosine and cordycepine in Cordyceps genus herbs was developed. The sample was extracted with 0.5% phosphoric acid solution to prepare test solution. The separation was performed on a Zorbax SB-Aq (4.6 mm×150 mm, 5 μm) column with gradient elution by 0.04 mol•L⁻¹ potassium dihydrogen phosphate solution and acetonitrile, column temperature 30 ℃,flow rate 0.8 mL•min⁻¹,and detection wavelength 260 nm. The content of nucleosides in four Cordyceps genus herbs was evaluated by fingerprint analysis and hierarchical cluster analysis (HCA). The calibration curves of five nucleosides showed good linear regression (r>0.99) and the average recoveries were between 95.0% and 105.0%. The contents of the five nucleosides in the four Cordyceps genus herbs were different and could be obviously distinguished by HCA. The fingerprint analysis result showed that the similarity between C. sinensis and the others was less than 0.9. The method was accurate and reliable, which can be used for quality control of Cordyceps genus herbs. Copyright© by the Chinese Pharmaceutical Association.

  3. GENUS RUELLIA: PHARMACOLOGICAL AND PHYTOCHEMICAL IMPORTANCE IN ETHNOPHARMACOLOGY.

    Science.gov (United States)

    Afzal, Khurram; Uzair, Muhammad; Chaudhary, Bashir Ahmad; Ahmad, Ashfaq; Afzal, Samina; Saadullah, Malik

    2015-01-01

    Ruellia is a genus of flowering plants commonly known as Ruellias or Wild Petunias which belongs to the family Acanthaceae. It contains about 250 genera and 2500 species. Most of these are shrubs, or twining vines; some are epiphytes. Only a few species are distributed in temperate regions. They are distributed in Indonesia and Malaysia, Africa, Brazil, Central America and Pakistan. Some of these are used as medicinal plants. Many species of the genus has antinociceptive, antioxidant, analgesic, antispasmolytic, antiulcer, antidiabetic and anti-inflammatory properties. The phytochemicals constituents: glycosides, alkaloids, flavonoids and triterpenoids are present. The genus has been traditionally claimed to be used for the treatment of flu, asthma, fever, bronchitis, high blood pressure, eczema, and diabetes. The objective of this review article is to summarize all the pharmacological and phytochemical evaluations or investigations to find area of gap and endorse this genus a step towards commercial drug. Hence, further work required is to isolate and characterize the active compounds responsible for these activities in this plant and bring this genus plants to commercial health market to serve community with their potential benefits.

  4. F-theory on Genus-One Fibrations

    CERN Document Server

    Braun, Volker

    2014-01-01

    We argue that M-theory compactified on an arbitrary genus-one fibration, that is, an elliptic fibration which need not have a section, always has an F-theory limit when the area of the genus-one fiber approaches zero. Such genus-one fibrations can be easily constructed as toric hypersurfaces, and various $SU(5)\\times U(1)^n$ and $E_6$ models are presented as examples. To each genus-one fibration one can associate a $\\tau$-function on the base as well as an $SL(2,\\mathbb{Z})$ representation which together define the IIB axio-dilaton and 7-brane content of the theory. The set of genus-one fibrations with the same $\\tau$-function and $SL(2,\\mathbb{Z})$ representation, known as the Tate-Shafarevich group, supplies an important degree of freedom in the corresponding F-theory model which has not been studied carefully until now. Six-dimensional anomaly cancellation as well as Witten's zero-mode count on wrapped branes both imply corrections to the usual F-theory dictionary for some of these models. In particular, n...

  5. Genotyping of clinical isolates of Acanthamoeba genus in Venezuela.

    Science.gov (United States)

    Wagner, Carolina; Reyes-Batlle, María; Ysea, María Alejandra Vethencourt; Pérez, Mónica V Galindo; de Rondón, Carmen Guzmán; Paduani, Anaibeth J Nessi; Pérez, Angelyseb Dorta; López-Arencibia, Atteneri; Sifaoui, Ines; de Galindo, María Virginia Pérez; de Suárez, Eva Pérez; Martínez-Carretero, Enrique; Valladares, Basilio; Piñero, José E; Lorenzo-Morales, Jacob

    2016-12-01

    Free-living amoebae of Acanthamoeba genus are opportunistic pathogens distributed worldwide. Strains included in this genus are causative agents of a fatal encephalitis and a sight-threating keratitis in humans and other animals. In this study, 550 clinical samples which were collected between 1984 and 2014 from different patients with suspected infections due to Acanthamoeba were initially screened for the presence of this amoebic genus at the Laboratorio de Amibiasis-Escuela de Bioanálisis at the Universidad Central de Venezuela. Samples were cultured in 2% Non-Nutrient agar plates seeded with a layer of heat killed Escherichia coli. From the 550 clinical samples included in this study, 18 of them were positive for Acanthamoeba genus after culture identification. Moreover, positive samples were confirmed after amplification of the Diagnostic Fragment 3 (DF3) of the Acanthamoeba18S rDNA genus and sequencing was carried out in order to genotype the isolated strains of Acanthamoeba. Furthermore, the pathogenic potential of the strains was checked by performing thermotolerance and osmotolerance assays. Sequencing of the DF3 region resulted in the identification of genotype T4 in all the isolated strains. Moreover, most isolates were thermotolerant or both thermotolerant and osmotolerant and thus were classified as potentially pathogenic strains. To the best of our knowledge, this is the first report on the molecular characterization at the genotype level of Acanthamoeba strains in Venezuela.

  6. Pollen morphology of the genus Cornukaempferia (Zingiberaceae) in Thailand

    Institute of Scientific and Technical Information of China (English)

    Piyaporn SAENSOUK; Pranom CHANTARANOTHAI; Piyada THEERAKULPISUT

    2009-01-01

    Cornukaempferia is a recently described genus of Zingiberaceae which only occurs in Thailand as a rare genus with limited geographical distribution. Only three species have been described so far, including a recently described new species, C. larsenii. These three species are morphologically very similar and additional data on other biological aspects are useful for the elucidation of their relationship. Pollen morphology of all three species of genus Cornukaempferia has been studied by light microscopy and scanning electron microscopy. The pollen grains are monad, spherical, inaperturate. The exine sculpture is echinate with psilate between the spines for C. aurantiflora and C. longipetiolata, or echinate with regulate between the spines for C. larsenii. This obser-vation helps support the taxonomic status of C. larsenii.

  7. Genetic variability assessment in the genus Passiflora by SSR markers

    Directory of Open Access Journals (Sweden)

    Claudia Lougon Paiva

    2014-09-01

    Full Text Available The genus Passiflora encompasses many species that are endemic to the Brazilian territory, including some with economic value. Studies on genetic diversity in this genus are fundamental because they allow understanding genetic variability and distance. The present study aimed to determine the genetic variability and distances among 10 species of the genus Passiflora by using microsatellite markers (Simple Sequence Repeat, SSR. Twenty-eight heterologous microsatellite markers were tested, but only 12 were used in the diversity analysis because they amplified in at least 80% of the species. A clear separation was observed among the subgenuses studied, as well as wide variation among the accessions of Passiflora. This knowledge enables breeders to explore diversity and transfer favorable alleles found in wild species.

  8. [Advances in chemical constituents and bioactivity of Salvia genus].

    Science.gov (United States)

    Peng, Qing; Liu, Jian-xun

    2015-06-01

    The genus Salvia in the family Lamiaceae with nearly 1 000 species, is widespread in temperate and tropical regions around the world. Many species of genus Salvia are important medicinal plants with a long history of which Danshen (the dried roots and rhizomes of S. miltiorrhiza) is one of the most popular herbal traditional medicines in Asian countries. The chemical constituents from Salvia plants mainly contain sesquiterpenoids, diterpenoids, triterpenoids, steroids and polyphenols etc, which exhibit antibacterial, antidermatophytic, antioxidant, anti-inflammatory, antineoplastic, antiplatelet aggregation activities and so on. In this article, the development of new constituents and their biological activities of Salvia genus in the past five years were reviewed and summarized for its further development and utilization.

  9. Genus Monilinia on Pome and Stone Fruit Species

    Directory of Open Access Journals (Sweden)

    Jovana Hrustić

    2012-01-01

    Full Text Available Different species of the genus Monilinia are common plant pathogens that endangerpome and stone fruit production worldwide. In Serbia, two species of this genus are widelydistributed – M. laxa and M. fructigena, while M. fructicola, which is officially on the A2 EPPOList of quarantine pest organisms in Europe and on the 1A part I List of quarantine pest organismsin Serbia, has so far been detected only on stored apple and nectarine fruits. The mostimportant control measures against these pathogens include chemical control in combinationwith adequate cultural practices, particularly under favourable conditions for diseasedevelopment. Concerning that species of this genus can cause significant economic losses,knowledge of the pathogen biology, disease epidemiology and pathogen-host interactionsis a necessary prerequisite for stable and profitable production of pome and stone fruits.

  10. A palynotaxonomic study of the genus Filipendula (Rosaceae)

    Institute of Scientific and Technical Information of China (English)

    Sangtae LEE; Meekyung KANG; Kyeong-In HEO; Wen-Li CHEN; Chunghee LEE

    2009-01-01

    Pollen grains from 15 species (18 taxa) of the genus Filipendula were examined with light and scan-ning electron microscopy. It was revealed that the pollen grains are isopolar, tricolporate, with scabrate or scabrate-microechinate surface. The pollen morphology was compared with the conventional classification sys-tems of the genus by different authors, and supported Shimizu's system (1961), in which the genus was divided into three subgenera. The monotypic subgen. Hypogyna is characterized by pollen lacking fastigium and thickened costae colpi. The other monotypic subgen. Filipendula differs from others by pollen having larger grain, larger pore size, longitudinally elliptic fastigium and thickened costae colpi. The largest subgen. Ulmaria is distinguished by pollen having rounded or latitudinally elliptic fastigium and thickened costae colpi. Sectional classification was not supported by the pollen morphology due to insufficient variability.

  11. Fossil history and modern distribution of the genus Abies (Pinaceae)

    Institute of Scientific and Technical Information of China (English)

    XIANG Xiaoguo; CAO Ming; ZHOU Zhekun

    2007-01-01

    The plants of the genus Abies are dominant and key species in the dark coniferous forest in the Northern Hemisphere.There are 52 species,one subspecies and 12 varieties in the genus Abies in the world.The history and modern distribution of Abies were discussed.The genus has three modern distribution centers:South Europe,North America and East Asia.These areas are also rich in fossil records.The vertical distribution regions of Abies are from sea level to an elevation of 4,700 m,concentrated in 1,000-2,000 m(15 species).In China,the genus distributes in 20 provinces,especially abundant in the Hengduan Mountains.Meanwhile,endemic and relic phenomena are obvious in this genus.There are seven relic species with both limited individuals and limited distributed regions.Based on the fossil records and the latest phylogenetic data,the following hypothesis was proposed:Abies originated from the middle and high altitudes of the Northern Hemisphere in the middle Cretaceous and it was dispersed southward in the Eocene due to global climate cooling down.The distribution of Abies was deeply influenced by geological events such as the uplift of Himalaya,the Alps,the Rocky Mountains,the occurrence of the Asian Monsoon as well as the Quaternary glaciers.Finally,the current distribution pattern appeared in the Quaternary.The genus Abies has a fossil history and modern distribution pattern similar to that of Cathaya and Pseudolarix.

  12. Revisiting the genus Photobacterium: taxonomy, ecology and pathogenesis.

    Science.gov (United States)

    Labella, Alejandro M; Arahal, David R; Castro, Dolores; Lemos, Manuel L; Borrego, Juan J

    2017-03-01

    The genus Photobacterium, one of the eight genera included in the family Vibrionaceae, contains 27 species with valid names and it has received attention because of the bioluminescence and pathogenesis mechanisms that some of its species exhibit. However, the taxonomy and phylogeny of this genus are not completely elucidated; for example, P. logei and P. fischeri are now considered members of the genus Aliivibrio, and previously were included in the genus Vibrio. In addition, P. damselae subsp. piscicida was formed as a new combination for former Vibrio damsela and Pasteurella piscicida. Moreover, P. damselae subsp. damselae is an earlier heterotypic synonym of P. histaminum. To avoid these incovenences draft and complete genomic sequences of members of Photobacterium are increasingly becoming available and their use is now routine for many research laboratories to address diverse goals: species delineation with overall genomic indexes, phylogenetic analyses, comparative genomics, and phenotypic inference. The habitats and isolation source of the Photobacterium species include seawater, sea sediments, saline lake waters, and a variety of marine organisms with which the photobacteria establish different relationships, from symbiosis to pathogenic interactions. Several species of this genus contain bioluminescent strains in symbiosis with marine fish and cephalopods; in addition, other species enhance its growth at pressures above 1 atmosphere, by means of several high-pressure adaptation mechanisms and for this, they may be considered as piezophilic (former barophilic) bacteria. Until now, only P. jeanii, P. rosenbergii, P. sanctipauli, and the two subspecies of P. damselae have been reported as responsible agents of several pathologies on animal hosts, such as corals, sponges, fish and homeothermic animals. In this review we have revised and updated the taxonomy, ecology and pathogenicity of several members of this genus. [Int Microbiol 20(1): 1-10 (2017

  13. Comparative Genomics Reveals High Genomic Diversity in the Genus Photobacterium.

    Science.gov (United States)

    Machado, Henrique; Gram, Lone

    2017-01-01

    Vibrionaceae is a large marine bacterial family, which can constitute up to 50% of the prokaryotic population in marine waters. Photobacterium is the second largest genus in the family and we used comparative genomics on 35 strains representing 16 of the 28 species described so far, to understand the genomic diversity present in the Photobacterium genus. Such understanding is important for ecophysiology studies of the genus. We used whole genome sequences to evaluate phylogenetic relationships using several analyses (16S rRNA, MLSA, fur, amino-acid usage, ANI), which allowed us to identify two misidentified strains. Genome analyses also revealed occurrence of higher and lower GC content clades, correlating with phylogenetic clusters. Pan- and core-genome analysis revealed the conservation of 25% of the genome throughout the genus, with a large and open pan-genome. The major source of genomic diversity could be traced to the smaller chromosome and plasmids. Several of the physiological traits studied in the genus did not correlate with phylogenetic data. Since horizontal gene transfer (HGT) is often suggested as a source of genetic diversity and a potential driver of genomic evolution in bacterial species, we looked into evidence of such in Photobacterium genomes. Genomic islands were the source of genomic differences between strains of the same species. Also, we found transposase genes and CRISPR arrays that suggest multiple encounters with foreign DNA. Presence of genomic exchange traits was widespread and abundant in the genus, suggesting a role in genomic evolution. The high genetic variability and indications of genetic exchange make it difficult to elucidate genome evolutionary paths and raise the awareness of the roles of foreign DNA in the genomic evolution of environmental organisms.

  14. Ethnomedicinal uses, phytochemistry and pharmacological properties of the genus Boerhavia.

    Science.gov (United States)

    Patil, Kapil S; Bhalsing, Sanjivani R

    2016-04-22

    The genus Boerhavia is widely distributed in tropical, subtropical and temperate regions of the world including Mexico, America, Africa, Asia, Indian Ocean Islands, Pacific Islands and Australia. The genus Boerhavia is extensively used by local peoples and medicinal practitioners for treatments of hepatitis, urinary disorders, gastro intestinal diseases, inflammations, skin problems, infectious diseases and asthma. Present review focused on traditional uses, phytochemistry, pharmacology and toxicology of Boerhavia genus to support potential scope for advance ethnopharmacological study. Information on the Boerhavia species was collected from classical books on medicinal plants, pharmacopoeias and scientific databases like PubMed, Scopus, GoogleScholar, Web of Science and others. Also scientific literatures based on ethnomedicinal surveys, Ph.D. and M.Sc. dissertations, published papers from Elsevier, Taylor and Francis, Springer, ACS as well as Wiley publishers and reports by government bodies and documentations were assessed. A total of 180 compounds from Boerhavia genus were isolated of which B. diffusa alone shared around 131 compounds and for most of which it is currently an exclusive source. In the genus, phenolic glycosides and flavonoids contribute approximately 97 compounds. These includes eupalitin, rotenoids like boeravinones, coccineons, alkaloid i.e. betanin and punarnavine etc., showing vital pharmaceutical activities such as anticancer, anti-inflammatory, antioxidant and immunomodulatory. Boerhavia is an important genus with wide range of medicinal uses. However, most of the available scientific literatures have lacked relevant doses, duration and positive controls for examining bioefficacy of extracts and its active compounds. In some studies, taxonomic errors were encountered. Moreover, there is need for accurate methods in testing the safety and ethnomedicinal validity of Boerhavia species. Copyright © 2016. Published by Elsevier Ireland Ltd.

  15. Taxonomic review of the Neotropical genus Neopachylus (Arachnida, Opiliones, Gonyleptidae

    Directory of Open Access Journals (Sweden)

    Vivian Moreira Montemor

    2015-03-01

    Full Text Available A taxonomic review of the genus Neopachylus Roewer, 1913 together with keys to the species for both males and females are presented. Gephyropachylus marginatus Mello-Leitão, 1931 is considered a junior subjective synonym of Neopachylus serrinha Soares & Soares, 1947, and Huralvius incertus Mello-Leitão, 1935 is considered a synonym of Neopachylus nebulosus (Mello-Leitão, 1936. This genus is restricted to southern Brazil, occurring in states of Paraná, Santa Catarina and Rio Grande do Sul.

  16. Revision of the genus Altitatiayus Weinreich(Coleoptera, Lucanidae, Lucaninae

    Directory of Open Access Journals (Sweden)

    Paschoal C. Grossi

    2010-01-01

    Full Text Available Revision of the genus Altitatiayus Weinreich (Coleoptera, Lucanidae, Lucaninae. The South American genus Altitatiayus Weinreich is revised and now includes six species, A. rotundatus (Boileau, A. ruficollis (Lüderwaldt, A. godinhorum (Bomans & Arnaud, A. dulceae (Bomans & Arnaud, A. trifurcatus (Grossi & Racca-Filho and A. koikei sp. nov. (Minas Gerais, Brazil. All species are described and illustrated. For the first time male and female genitalia are illustrated for five species and observations on the behavior of two species are included.

  17. Revision of the genus Rennellia Korth. (Rubiaceae-Rubioideae)

    OpenAIRE

    Johansson, J.T.

    1989-01-01

    In this revision of the genus Rennellia Korth. four species are recognized: R. elliptica Korth., R. amoena (Bremek.) J.T. Johansson comb, nov., R. speciosa (Wall, ex Kurz) J.D. Hooker, and R. morindiformis (Korth.) Ridley. Rennellia includes shrubs and small trees with white to pale bluish or pale violet flowers in panicle-, umbel-, or spike-like cymes. The pedicels and ovaries are nearly always connate. Rennellia is confined to tropical rain forests in SE Asia, Sumatra, and Borneo. The genus...

  18. Holographic partition functions and phases for higher genus Riemann surfaces

    Science.gov (United States)

    Maxfield, Henry; Ross, Simon F.; Way, Benson

    2016-06-01

    We describe a numerical method to compute the action of Euclidean saddle points for the partition function of a two-dimensional holographic CFT on a Riemann surface of arbitrary genus, with constant curvature metric. We explicitly evaluate the action for the saddles for genus two and map out the phase structure of dominant bulk saddles in a two-dimensional subspace of the moduli space. We discuss spontaneous breaking of discrete symmetries, and show that the handlebody bulk saddles always dominate over certain non-handlebody solutions.

  19. Phylogenetic analysis of the genus Hordeum using repetitive DNA sequences

    DEFF Research Database (Denmark)

    Svitashev, S.; Bryngelsson, T.; Vershinin, A.

    1994-01-01

    A set of six cloned barley (Hordeum vulgare) repetitive DNA sequences was used for the analysis of phylogenetic relationships among 31 species (46 taxa) of the genus Hordeum, using molecular hybridization techniques. In situ hybridization experiments showed dispersed organization of the sequences...... over all chromosomes of H. vulgare and the wild barley species H. bulbosum, H. marinum and H. murinum. Southern blot hybridization revealed different levels of polymorphism among barley species and the RFLP data were used to generate a phylogenetic tree for the genus Hordeum. Our data are in a good...

  20. Review of the genus Agria (Diptera, Sarcophagidae) from China

    DEFF Research Database (Denmark)

    Zhang, Ming; Chen, Yi-ou; Pape, Thomas

    2013-01-01

    Agria mihalyii (Rohdendorf and Verves, 1978) is recorded from China for the first time, and both sexes are thoroughly documented using a combination of illustrations, photographs and scanning electron microscopy images. The generic affiliation is corroborated from an expanded definition of genus...... Agria Robineau-Desvoidy, 1830, and a key to males of the two known species from China is provided. The distribution of coeloconic sensilla on the male pre- and postgonite are shown to possess significant diagnostic and phylogenetic information in this genus....

  1. Revision of the neotropical genus Sendaphne Nixon (Hymenoptera, Braconidae, Microgastrinae

    Directory of Open Access Journals (Sweden)

    Jose L. Fernandez-Triana

    2014-12-01

    Full Text Available The Neotropical genus of parasitoid wasps Sendaphne (Hymenoptera, Braconidae, Microgastrinae is revised and the following six new species are described, all authored by Fernández-Triana and Whitfield: anitae, bennetti, broadi, dianariaspennae, penteadodiasae, and rogerblancoi. The greatest species richness is found in northern South America, but the genus extends north to 23° N in Mexico. Most species have been collected in rainforest below altitudes of 900 m, with only a few species found in cloud forests up to 1900 m. Nothing is known of the host caterpillars for these parasitoid wasps.

  2. Revision of the genus Philoplitis Nixon (Hymenoptera, Braconidae, Microgastrinae

    Directory of Open Access Journals (Sweden)

    Jose Fernandez-Triana

    2009-09-01

    Full Text Available The genus Philoplitis Nixon is revised. Three new species, P. masneri Fernández-Triana & Goulet, sp. n., P. punctatus Fernández-Triana & Goulet, sp. n., and P. striatus Fernández-Triana & Goulet, sp. n. are described, and a key is provided to the World species. The genus, previously known only from the Oriental region, is here recorded from the Afrotropical region. Evidence suggests that its included species are broadly found in rainforest areas of the Old World tropics. Clarification and suggestions about some character states previously used with Philoplitis within the context of Microgastrinae phylogenetic studies are also provided.

  3. Revision of the genus Endochilus Weise (Coleoptera: Coccinellidae: Chilocorini).

    Science.gov (United States)

    Łączyński, Piotr; Tomaszewska, Wioletta

    2014-05-20

    The members of the endemic African genus Endochilus Weise, 1898 (Coleoptera: Coccinellidae: Chilocorini) are redescribed, diagnosed, and illustrated. Lectotypes are designated for Endochilus compater Weise, Endochilus minor Weise, Endochilus plagiatus Sicard, Endochilus rubicundus Weise, and Endochilus styx Sicard. One new species is described: Endochilus abdominalis sp nov. Notes on the genus and nomenclatural history for each species are provided. A key for identification of all species is presented. Adult characters concerning similarities of Endochilus to other genera of African Chilocorini are discussed. This is an open access paper. We use the Creative Commons Attribution 3.0 license that permits unrestricted use, provided that the paper is properly attributed.

  4. Evolution of the leukotoxin operon in genus Mannheimia

    DEFF Research Database (Denmark)

    Larsen, J.; Pedersen, A. G.; Christensen, H.;

    2005-01-01

    The leukotoxin protein of Mannheimia haemolytica belongs to the HlyA-like subfamily of cytotoxic RTX (repeats in toxin) proteins. To test the hypothesis that different lineages of genus Mannheimia gained the leukotoxin operon via horizontal gene transfer we used a strategy that combines compositi......The leukotoxin protein of Mannheimia haemolytica belongs to the HlyA-like subfamily of cytotoxic RTX (repeats in toxin) proteins. To test the hypothesis that different lineages of genus Mannheimia gained the leukotoxin operon via horizontal gene transfer we used a strategy that combines...

  5. The genus Boschniakia in China: An ethnopharmacological and phytochemical review.

    Science.gov (United States)

    Zhang, Le; Zhao, Yunshan; Wang, Zhipeng A; Wei, Kunhua; Qiu, Bin; Zhang, Chunhong; Wang-Müller, QiYan; Li, Minhui

    2016-12-24

    As a group of important medicine plants, Boschniakia rossica (Cham. et Schltdl) Fedtsch. and B. himalaica Hook.f.et Thoms, which are the only two species in the genus Boschniakia (Orobanchaceae), have long been used in traditional Chinese medicine for their multiple therapeutic uses related to enhanced renal function, erectile dysfunction, defaecate and hepatoprotective. Additionally, the two species are also used as dietary supplements in wine, cosmetics, and other healthy food. By providing comprehensive information and data of genus Boschniakia on botany, traditional medicinal uses, phytochemistry, pharmacological research and toxicology, this review aims to summary the group of natural compounds from Boschniakia discovered so far. The other aims are to reference research findings of their biological activities and functions in medicine, physiology, and cell biology to highlight the compound candidates which can be used for further drug discovery in several pharmaceutical areas including antioxidation, anticancer, anti-inflammation, anti-senile, and immunology. All of the available information on B. rossica and B. himalaica was collected from the electronic resources (such as PubMed, SciFinder Scholar, CNKI, TPL (www.theplantlist.org), Google Scholar, Baidu Scholar, and Web of Science). After a comprehensive analysis of the literatures from available online sources, the results show that both species of genus Boschniakia are valuable and popular herbal medicines with potentials to cure various ailments. The phytochemical studies revealed that the chemical compositions of this genus were mainly iridoid glycosides and phenylpropanoid glycosides. To date, 112 compounds have been isolated from the genus, while their crude extracts and purified compounds have been found to possess a wide range of biological activities including anti-senile, antitumor and anticancer, anti-inflammatory, protecting liver, boost memory, anti-oxidation, anti-lipid peroxidative, and

  6. Bioactive Natural Products of Marine Sponges from the Genus Hyrtios

    Directory of Open Access Journals (Sweden)

    Nourhan Hisham Shady

    2017-05-01

    Full Text Available Marine sponges are known as a rich source for novel bioactive compounds with valuable pharmacological potential. One of the most predominant sponge genera is Hyrtios, reported to have various species such as Hyrtios erectus, Hyrtios reticulatus, Hyrtios gumminae, Hyrtios communis, and Hyrtios tubulatus and a number of undescribed species. Members of the genus Hyrtios are a rich source of natural products with diverse and valuable biological activities, represented by different chemical classes including alkaloids, sesterterpenes and sesquiterpenes. This review covers the literature until June 2016, providing a complete survey of all compounds isolated from the genus Hyrtios with their corresponding biological activities whenever applicable.

  7. A study on the genus Digitaria (Poaceae in Iran

    Directory of Open Access Journals (Sweden)

    Mohammad Amini Rad

    2015-10-01

    Full Text Available In current research, the genus Digitaria has been studied in Iran. As a results, D. ischaemum, D. sanguinalis, D. sabulosa, D. ciliaris, D. nodosa with D. violascens which is reported for the first time from Iran here, are confirmed for the flora of Iran. In addition, the record of D. stricta from Iran is rejected as referable to D. violascens after the studying their specimens. Finally, a key to all species of the genus Digitaria in Iran along with morphological descriptions of species are provided.

  8. Landau-Ginzburg Orbifolds, Mirror Symmetry and the Elliptic Genus

    OpenAIRE

    Berglund, P.; Henningson, M.

    1994-01-01

    We compute the elliptic genus for arbitrary two dimensional $N=2$ Landau-Ginzburg orbifolds. This is used to search for possible mirror pairs of such models. We show that if two Landau-Ginzburg models are conjugate to each other in a certain sense, then to every orbifold of the first theory corresponds an orbifold of the second theory with the same elliptic genus (up to a sign) and with the roles of the chiral and anti-chiral rings interchanged. These orbifolds thus constitute a possible mirr...

  9. Note on twisted elliptic genus of K3 surface

    Energy Technology Data Exchange (ETDEWEB)

    Eguchi, Tohru, E-mail: eguchi@yukawa.kyoto-u.ac.j [Yukawa Institute for Theoretical Physics, Kyoto University, Kyoto 606-8502 (Japan); Hikami, Kazuhiro, E-mail: KHikami@gmail.co [Department of Mathematics, Naruto University of Education, Tokushima 772-8502 (Japan)

    2011-01-03

    We discuss the possibility of Mathieu group M{sub 24} acting as symmetry group on the K3 elliptic genus as proposed recently by Ooguri, Tachikawa and one of the present authors. One way of testing this proposal is to derive the twisted elliptic genera for all conjugacy classes of M{sub 24} so that we can determine the unique decomposition of expansion coefficients of K3 elliptic genus into irreducible representations of M{sub 24}. In this Letter we obtain all the hitherto unknown twisted elliptic genera and find a strong evidence of Mathieu moonshine.

  10. Holographic partition functions and phases for higher genus Riemann surfaces

    CERN Document Server

    Maxfield, Henry; Way, Benson

    2016-01-01

    We describe a numerical method to compute the action of Euclidean saddlepoints for the partition function of a two-dimensional holographic CFT on a Riemann surface of arbitrary genus, with constant curvature metric. We explicitly evaluate the action for the saddles for genus two and map out the phase structure of dominant bulk saddles in a two-dimensional subspace of the moduli space. We discuss spontaneous breaking of discrete symmetries, and show that the handlebody bulk saddles always dominate over certain non-handlebody solutions.

  11. Fricke Lie algebras and the genus zero property in Moonshine

    Science.gov (United States)

    Carnahan, Scott

    2017-10-01

    We give a new, simpler proof that the canonical actions of finite groups on Fricke-type Monstrous Lie algebras yield genus zero functions in generalized Monstrous Moonshine, using a Borcherds–Kac–Moody Lie algebra decomposition due to Jurisich. We describe a compatibility condition, arising from the no-ghost theorem in bosonic string theory, that yields the genus zero property. We give evidence for and against the conjecture that such a compatibility for symmetries of the Monster Lie algebra gives a characterization of the Monster group.

  12. The genus Ontherus Erichson 1847 (Coleoptera: Scarabaeidae: Scarabaeinae): description of a new species, and notes on the genus in Colombia.

    Science.gov (United States)

    González, Fabio Arturo; Medina U, Claudia Alejandra

    2015-04-23

    The state of knowledge of the genus Ontherus Erichson 1847 in Colombia is reviewed and updated since the revision of the genus by Génier (1996), and the species list for Colombia of Medina et al. (2001). Two new distributional records for Colombia are confirmed; Ontherus politus Génier 1996 and Ontherus gilli Génier 1996. An updated species list of Ontherus for Colombia is presented with comments on the species with doubtful distribution in Colombia. O. felicitae n. sp., a new species from the mexicanus species group, is described from Western Andes of Colombia.

  13. Effects of management practices on grassland birds: Baird's Sparrow

    Science.gov (United States)

    Dechant, Jill A.; Sondreal, Marriah L.; Johnson, Douglas H.; Igl, Lawrence D.; Goldade, Christopher M.; Nenneman, Melvin P.; Euliss, Betty R.

    1998-01-01

    Information on the habitat requirements and effects of habitat management on grassland birds were summarized from information in more than 5,500 published and unpublished papers. A range map is provided to indicate the relative densities of the species in North America, based on Breeding Bird Survey (BBS) data. Although birds frequently are observed outside the breeding range indicated, the maps are intended to show areas where managers might concentrate their attention. It may be ineffectual to manage habitat at a site for a species that rarely occurs in an area. The species account begins with a brief capsule statement, which provides the fundamental components or keys to management for the species. A section on breeding range outlines the current breeding distribution of the species in North America, including areas that could not be mapped using BBS data. The suitable habitat section describes the breeding habitat and occasionally microhabitat characteristics of the species, especially those habitats that occur in the Great Plains. Details on habitat and microhabitat requirements often provide clues to how a species will respond to a particular management practice. A table near the end of the account complements the section on suitable habitat, and lists the specific habitat characteristics for the species by individual studies. A special section on prey habitat is included for those predatory species that have more specific prey requirements. The area requirements section provides details on territory and home range sizes, minimum area requirements, and the effects of patch size, edges, and other landscape and habitat features on abundance and productivity. It may be futile to manage a small block of suitable habitat for a species that has minimum area requirements that are larger than the area being managed. The Brown-headed Cowbird (Molothrus ater) is an obligate brood parasite of many grassland birds. The section on cowbird brood parasitism summarizes rates of cowbird parasitism, host responses to parasitism, and factors that influence parasitism, such as nest concealment and host density. The impact of management depends, in part, upon a species' nesting phenology and biology. The section on breeding-season phenology and site fidelity includes details on spring arrival and fall departure for migratory populations in the Great Plains, peak breeding periods, the tendency to renest after nest failure or success, and the propensity to return to a previous breeding site. The duration and timing of breeding varies among regions and years. Species' response to management summarizes the current knowledge and major findings in the literature on the effects of different management practices on the species. The section on management recommendations complements the previous section and summarizes specific recommendations for habitat management provided in the literature. If management recommendations differ in different portions of the species' breeding range, recommendations are given separately by region. The literature cited contains references to published and unpublished literature on the management effects and habitat requirements of the species. This section is not meant to be a complete bibliography; for a searchable, annotated bibliography of published and unpublished papers dealing with habitat needs of grassland birds and their responses to habitat management, use the Grassland and Wetland Birds Bibliography on the home page of this resource.

  14. Revision of the genus Cleistanthus (Euphorbiaceae) in the Philippines

    NARCIS (Netherlands)

    Dressler, Stefan

    1999-01-01

    The Philippine species of the euphorbiaceous genus Cleistanthus are revised. Sixteen species are recognised for this archipelago of which two are recorded from there for the first time. The oldest available combination from the Philippines [C. orgyalis (Blanco) Merr.] remains obscure and three colle

  15. Revision of the Genus Hybosorus Macleay (Coleoptera: Scarabaeidae, Hybosorinae)

    NARCIS (Netherlands)

    Kuijten, P.J.

    1983-01-01

    A taxonomic revision of the scarabaeoid genus Hybosorus is given, including descriptions, nomenclatorial notes, figures of genital apparatus and other relevant parts, a key, and notes on distribution and bionomics. Lectotypes are designated for Hybosorus carolinus LeConte, H. crassus Klug, H. nitidu

  16. Resurrection of Angelesia, a Southeast Asian genus of Chrysobalanaceae

    NARCIS (Netherlands)

    Sothers, C.A.; Prance, G.T.

    2014-01-01

    Licania subg. Angelesia is composed of only three species restricted to Southeast Asia and is currently delimited as one of four subgenera of Licania, a species-rich genus of mostly Neotropical taxa. Molecular phylogenetic studies involving Chrysobalanaceae have revealed that Licania is polyphyletic

  17. A new genus of Staphylinidae (Coleoptera) from the Lower Cretaceous

    DEFF Research Database (Denmark)

    Schomann, Andrea Maria; Solodovnikov, Alexey

    2012-01-01

    The fossil genus of rove beetles Apticaxgen.n. with two new species, A. volanssp.n. and A. solidussp.n., is described from the Nova Olinda Member of the Crato Formation in north-eastern Brazil (Aptian–Albian, dated as 125–99.6 Ma old). Both species belong to the clade Staphylininae + Paederinae i...

  18. Notes on the genus Punctelia in Denmark

    DEFF Research Database (Denmark)

    Christensen, Steen; Søchting, Ulrik

    2007-01-01

    establishing the genus Punctelia, did not re-combine P. ulophylla, nor include it in the accompanying key. She probably considered it as a synonym of P. subrudecta. In a study on European Punctelia species with lecanoric acid, van Herk & Aptroot (2000) accepted the taxon and made the combination Punctelia...

  19. The genus Lentinus (Basidiomycetes from India - an annotated checklist

    Directory of Open Access Journals (Sweden)

    Sapan Kumar Sharma

    2015-09-01

    Full Text Available An annotated checklist of species of genus Lentinus has been presented in this paper. On scrutiny of the latest authentic literature and mycobank record, out of a total of 41 documented species from India, 20 were found to be valid species while 21 were invalid species which were found to be synonyms. 

  20. New genus of diminutive microhylid frogs from Papua New Guinea

    Directory of Open Access Journals (Sweden)

    Fred Kraus

    2010-06-01

    Full Text Available A new genus of diminutive (10.1-11.3 mm microhylid frogs is described from New Guinea that is unique in its combination ofonly seven presacral vertebrae, a reduced phalangeal formula that leaves the first fingers and first toes as vestigial nubs, and reduction of the prepollex and prehallux to single elements. Relationships to other genera are unknown, but overall similarity suggests some relationship to Cophixalus, although that genus also differs in some muscle characters and likely remains paraphyletic. The new genus contains two species, which are among the smallest known frogs in the world. Their miniaturization may be related to their inhabiting leaf litter, exploitation of which may for small size. The new genus is currently known only from one mountaintop in the southeasternmost portion of New Guinea and another on a nearby island. This region is part of the East Papuan Composite Terrane and, should this lineage prove endemic to that region, it may suggest that it originated prior to that geological unit’s docking with mainland New Guinea at 23–29 MY.