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Sample records for unisexual gynogenetic species

  1. Nonrandom patterns of genetic admixture expose the complex historical hybrid origin of unisexual leaf beetle species in the genus Calligrapha.

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    Montelongo, Tinguaro; Gómez-Zurita, Jesús

    2015-01-01

    Many unisexual animal lineages supposedly arose from hybridization. However, support for their putative hybrid origins mostly comes from indirect methodologies, which are rarely confirmatory. Here we provide compelling data indicating that tetraploid unisexual Calligrapha are true genetic mosaics obtained via analysis of mitochondrial DNA (mtDNA) and allelic variation and coalescence times for three single-copy nuclear genes (CPS, HARS, and Wg) in five of six unisexual Calligrapha and a representative sample of bisexual species. Nuclear allelic diversity in unisexuals consistently segregates in the gene pools of at least two but up to three divergent bisexual species, interpreted as putative parentals of interspecific hybridization crosses. Interestingly, their mtDNA diversity derives from an additional yet undiscovered older evolutionary lineage that is possibly the same for all independently originated unisexual species. One possibly extinct species transferred its mtDNA to several evolutionary lineages in a wave of hybridization events during the Pliocene, whereby descendant species retained a polymorphic mtDNA constitution. Recent hybridizations, in the Pleistocene and always involving females with the old introgressed mtDNA, seemingly occurred in the lineages leading to unisexual species, decoupling mtDNA introgression (and inferences derived from these data, such as timing and parentage) from subsequent acquisition of the new reproductive mode. These results illuminate an unexpected complexity in possible routes to animal unisexuality, with implications for the interpretation of ancient unisexuality. If the origin of unisexuality requires a mechanism where (1) hybridization is a necessary but insufficient condition and (2) multiple bouts of hybridization involving more than two divergent lineages are required, then the origins of several classical unisexual systems may have to be reassessed.

  2. Two unisexual artificial polyploid clones constructed by genome addition of common carp (Cyprinus carp) and crucian carp (Carassius auratus)

    Institute of Scientific and Technical Information of China (English)

    WU; Qingjiang; (吴清江); YE; Yuzhen; (叶玉珍); DONG; Xinhong; (董新红)

    2003-01-01

    A polyploid hybrid fish with natural gynogenesis can prevent segregation and maintain their hybrid vigor in their progenies. Supposing the reproduction mode of induced polyploid fish being natural gynogenesis, allopolyploid hybrid between common carp and crucian carp into allopolyploid was performed. The purpose of this paper is to describe a lineage from sexual diploid carp transforming into allotriploid and allotetraploid unisexual clones by genome addition. The diploid hybrid between common carp and crucian carp reproduces an unreduced nucleus consisting of two parental genomes. This unreduced female pronucleus will fuse with male pronucleus and form allotriploid zygote after penetration of related species sperms. Allotriploid embryos grow normally, and part of female allotriploid can produce unreduced mature ova with three genomes. Mature ova of most allotriploid females are provided with natural gynogenetic trait and their nuclei do not fuse with any entrance sperm. All female offspring are produced by gynogenesis of allotriploid egg under activation of penetrating sperms. These offspring maintain morphological traits of their allotriploid maternal and form an allotetraploid unisexual clone by gynogenetic reproduction mode. However, female nuclei of rare allotriploid female can fuse with penetrating male pronuclei and result in the appearance of allotetraploid individuals by means of genome addition. All allotetraploid females can reproduce unreduced mature eggs containing four genomes. Therefore, mature eggs of allotetraploid maintain gynogenetic trait and allotetraploid unisexual clone is produced under activation of related species sperms.

  3. Unisexual reproduction of Cryptococcus gattii.

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    Sujal S Phadke

    Full Text Available Cryptococcus gattii is a basidiomycetous human fungal pathogen that typically causes infection in tropical and subtropical regions and is responsible for an ongoing outbreak in immunocompetent individuals on Vancouver Island and in the Pacific Northwest of the US. Pathogenesis of this species may be linked to its sexual cycle that generates infectious propagules called basidiospores. A marked predominance of only one mating type (α in clinical and environmental isolates suggests that a-α opposite-sex reproduction may be infrequent or geographically restricted, raising the possibility of an alternative unisexual cycle involving cells of only α mating type, as discovered previously in the related pathogenic species Cryptococcus neoformans. Here we report observation of hallmark features of unisexual reproduction in a clinical isolate of C. gattii (isolate 97/433 and describe genetic and environmental factors conducive to this sexual cycle. Our results are consistent with population genetic evidence of recombination in the largely unisexual populations of C. gattii and provide a useful genetic model for understanding how novel modes of sexual reproduction may contribute to evolution and virulence in this species.

  4. Feeding rates in the sailfin molly Poecilia latipinna and its coexisting sexual parasite, the gynogenetic Amazon molly Poecilia formosa.

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    Fischer, C; Schlupp, I

    2010-07-01

    Feeding rates of the gynogenetic Amazon molly Poecilia formosa and one of its sexual hosts, the sailfin molly Poecilia latipinna, were measured under winter and summer temperature conditions. Food consumption of the unisexual P. formosa in winter conditions was significantly higher than that of P. latipinna, and it is hypothesized that the resulting food stress might have an important influence on the population composition of these closely related fishes via higher winter mortality in P. formosa.

  5. The prevalence of genome replacement in unisexual salamanders of the genus Ambystoma (Amphibia, Caudata revealed by nuclear gene genealogy

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    Bogart James P

    2008-05-01

    Full Text Available Abstract Background Unisexual salamanders of the genus Ambystoma exemplify the most ancient lineage of unisexual vertebrates and demonstrate an extremely flexible reproductive system. Unisexual Ambystoma interact with and incorporate genomes from two to four sexual species (A. laterale, A. jeffersonianum,A. texanum, and A. tigrinum, to generate more than 20 genome compositions or biotypes. Unisexual ploidy levels range from diploid to pentaploid, but all contain at least one A. laterale (L genome. Replacement of nuclear genomes might be responsible for the evolutionary longevity of unisexual Ambystoma but direct evidence for the prevalence of genome replacement in natural populations is absent. Two major puzzling questions have remained unanswered over the last few decades: 1 is genome replacement a common reproductive method in various unisexual populations and, 2 is there an ancient "L" genome that persists in various unisexual genome compositions. Results We examined 194 unisexual and 89 A. laterale specimens from 97 localities throughout their range and constructed a genealogy of the "L" genomes using a nuclear DNA marker (L-G1C12 to answer the above questions. Six L-G1C12 haplotypes (A-F were shared by individuals in various A. laterale and unisexual populations. The general geographical distribution of the haplotypes in unisexual populations conformed to those found in A. laterale, indicating that "L" genomes in unisexuals are obtained from sympatric or nearby populations of A. laterale. Conclusion Our data demonstrate that genome replacement frequently occurs in unisexual Ambystoma across their range, and support previous speculations that genome replacement is an important reproductive mechanism that can enhance their evolutionary longevity. Our results show that there is no ancient "L" genome in the unisexual lineages, and no particular "L" genome is favored in any unisexual individual. The presence of an "L" genome in all unisexuals

  6. Sex in unisexual salamanders: discovery of a new sperm donor with ancient affinities.

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    Bogart, J P; Bartoszek, J; Noble, D W A; Bi, K

    2009-12-01

    Although bisexual reproduction has considerable evolutionary benefits, several all-female vertebrates exist. Unisexual salamanders in the genus Ambystoma are common around the Great Lakes region in eastern North America. They originated from a hybridization event that involved a female that shared a common ancestor with Ambystoma barbouri 2.4 to 3.9 million years ago but, unexpectedly, A. barbouri nuclear genomes were unknown in unisexuals. Unisexual salamanders steal sperm from donors of normally bisexual species, so their reproductive mode is described as kleptogenesis. Most known unisexuals are polyploid and they all possess at least one A. laterale genome. One or more other genomes are taken from sperm donors that may include A. jeffersonianum, A. laterale, A. texanum and A. tigrinum. We examined unisexual adults and larvae in a southern Ohio pond where unisexual individuals coexist with male A. barbouri. This population provided an opportunity to test hypotheses pertaining to the role of A. barbouri in the evolution of the disparate cytoplasmic and nuclear genomes in unisexual salamanders. Microsatellite DNA loci, mitochondrial DNA sequences and genomic in situ hybridization were used to identify the genomic constitution of individuals. A. barbouri was found to be an acceptable sperm donor for unisexuals but only contributed genomes in ploidy-elevated individuals. In the absence of A. jeffersonianum, this Ohio population is likely experiencing a recent switch in sperm donors from A. jeffersonianum to A. barbouri and demonstrates the evolutionary flexibility and dynamics of kleptogenesis.

  7. The quest for molecular regulation underlying unisexual flower development

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    Rómulo eSobral

    2016-02-01

    Full Text Available The understanding of the molecular mechanisms responsible for the making of a unisexual flower has been a long-standing quest in plant biology. Plants with male and female flowers can be divided mainly into two categories: dioecious and monoecious, and both sexual systems co-exist in nature in ca of 10% of the angiosperms. The establishment of male and female traits has been extensively described in a hermaphroditic flower and requires the interplay of networks, directly and indirectly related to the floral organ identity genes including hormonal regulators, transcription factors, microRNAs, and chromatin-modifying proteins. Recent transcriptomic studies have been uncovering the molecular processes underlying the establishment of unisexual flowers and there are many parallelisms between monoecious, dioecious and hermaphroditic individuals. Here, we review the paper entitled Comparative transcriptomic analysis of male and female flowers of monoecious Quercus suber published in 2014 in the Frontiers of Plant Science (volume 5 | Article 599 and discussed it in the context of recent studies with other dioecious and monoecious plants that utilized high-throughput platforms to obtain transcriptomic profiles of male and female unisexual flowers. In some unisexual flowers, the developmental programs that control organ initiation fail and male or female organs do not form, whereas in other species, organ initiation and development occur but they abort or arrest during different species-specific stages of differentiation. Therefore, a direct comparison of the pathways responsible for the establishment of unisexual flowers in different species are likely to reveal conserved modules of gene regulatory hubs involved in stamen or carpel development, as well as differences that reflect the different stages of development in which male and/or female organ arrest or loss-of-function occurs.

  8. The Quest for Molecular Regulation Underlying Unisexual Flower Development

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    Sobral, Rómulo; Silva, Helena G.; Morais-Cecílio, Leonor; Costa, Maria M. R.

    2016-01-01

    The understanding of the molecular mechanisms responsible for the making of a unisexual flower has been a long-standing quest in plant biology. Plants with male and female flowers can be divided mainly into two categories: dioecious and monoecious, and both sexual systems co-exist in nature in ca of 10% of the angiosperms. The establishment of male and female traits has been extensively described in a hermaphroditic flower and requires the interplay of networks, directly and indirectly related to the floral organ identity genes including hormonal regulators, transcription factors, microRNAs, and chromatin-modifying proteins. Recent transcriptomic studies have been uncovering the molecular processes underlying the establishment of unisexual flowers and there are many parallelisms between monoecious, dioecious, and hermaphroditic individuals. Here, we review the paper entitled “Comparative transcriptomic analysis of male and female flowers of monoecious Quercus suber” published in 2014 in the Frontiers of Plant Science (volume 5 |Article 599) and discussed it in the context of recent studies with other dioecious and monoecious plants that utilized high-throughput platforms to obtain transcriptomic profiles of male and female unisexual flowers. In some unisexual flowers, the developmental programs that control organ initiation fail and male or female organs do not form, whereas in other species, organ initiation and development occur but they abort or arrest during different species-specific stages of differentiation. Therefore, a direct comparison of the pathways responsible for the establishment of unisexual flowers in different species are likely to reveal conserved modules of gene regulatory hubs involved in stamen or carpel development, as well as differences that reflect the different stages of development in which male and/or female organ arrest or loss-of-function occurs. PMID:26925078

  9. Population genomics reveals a possible history of backcrossing and recombination in the gynogenetic fish Poecilia formosa.

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    Alberici da Barbiano, Laura; Gompert, Zachariah; Aspbury, Andrea S; Gabor, Caitlin R; Nice, Chris C

    2013-08-20

    Unisexual sperm-dependent vertebrates are of hybrid origins, rare, and predicted to be short-lived as a result of several challenges arising from their mode of reproduction. In particular, because of a lack of recombination, clonal species are predicted to have a low potential to respond to natural selection. However, many unisexual sperm-dependent species persist, and assessing the genetic diversity present in these species is fundamental to understanding how they avoid extinction. We used population genomic methods to assess genotypic variation within the unisexual fish Poecilia formosa. Measures of admixture and population differentiation, as well as clustering analyses, indicate that the genomes of individuals of P. formosa are admixed and intermediate between Poecilia latipinna and Poecilia mexicana, consistent with the hypothesis of their hybrid origins. Bayesian genomic cline analyses indicate that about 12% of sampled loci exhibit patterns consistent with inheritance from only one parent. The estimation of observed heterozygosity clearly suggests that P. formosa is not comprised of direct descendants of a single nonrecombining asexual F1 hybrid individual. Additionally, the estimation of observed heterozygosity provides support for the hypothesis that the history of this unisexual species has included backcrossing with the parent species before the onset of gynogenesis. We also document high levels of variation among asexual individuals, which is attributable to recombination (historical or ongoing) and the accumulation of mutations. The high genetic variation suggests that this unisexual vertebrate has more potential to respond to natural selection than if they were frozen F1 hybrids.

  10. A single nucleotide polymorphism assay for the identification of unisexual Ambystoma salamanders.

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    Greenwald, Katherine R; Lisle Gibbs, H

    2012-03-01

    Unisexual (all female) salamanders in the genus Ambystoma are animals of variable ploidy (2N-5N) that reproduce via a unique system of 'leaky' gynogenesis. As a result, these salamanders have a diverse array of nuclear genome combinations from up to five sexual species: the blue-spotted (A. laterale), Jefferson (A. jeffersonianum), smallmouth (A. texanum), tiger (A. tigrinum) and streamside (A. barbouri) salamanders. Identifying the genome complement, or biotype, is a critical first step in addressing a broad range of ecological and evolutionary questions about these salamanders. Previous work relied upon genome-related differences in allele size distributions for specific microsatellite loci, but overlap in these distributions among different genomes makes definitive identification and ploidy determination in unisexuals difficult or impossible. Here, we develop the first single nucleotide polymorphism assay for the identification of unisexual biotypes, based on species-specific nucleotide polymorphisms in noncoding DNA loci. Tests with simulated and natural unisexual DNA samples show that this method can accurately identify genome complement and estimate ploidy, making this a valuable tool for assessing the genome composition of unisexual samples.

  11. Unexpectedly high genetic variation in large unisexual clumps of the subdioecious plant Honckenya peploides

    DEFF Research Database (Denmark)

    Sánchez-Vilas, Julia; Philipp, Marianne; Retuerto, Rubén

    2010-01-01

    Honckenya peploides is a subdioecious dune plant that reproduces both sexually and by clonal growth. In northwest Spain this species was found to exhibit an extreme spatial segregation of the sexes, and our objective was to investigate genetic variation in unisexual clumps. Genetic variation was ...

  12. Anatomy and ontogeny of unisexual flowers in dioecious Woonyoungia septentrionalis (Dandy) Law (Magnoliaceae)

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    Lin FU; Qing-Wen ZENG; Jing-Ping LIAO; Feng-Xia XU

    2009-01-01

    Woonyoungia septentrionalis (Dandy) Law is a dioecious species with unisexual flowers in Magnoli-aceae. The floral morphology and structure of the species are conspicuously different from other species and are important to the study of floral phylogeny in this family. The floral anatomy and ontogeny were investigated to evaluate the systematic position of W. septentrionalis, using scanning electron microscopy and light microscopy. All of the floral organs are initiated acropetally and spirally. The carpels are of conduplicated type without the differentiation of stigma and style. The degenerated stamens in the female flowers have the same structures as the normal stamens at the earlier developmental stages, but they do not undergo successive development and eventually degenerate. The male floral apex was observed to have the remnants of carpels in a few investigated samples. As the bisexual flower features could be traced both in the male and female flowers in W. septentrionalis, it suggests that the flower sex in Magnoliaceae tends toward unisexual. As well as the unisexual flowers, the reduced tepals and carpels and concrescence of carpels conform to the specialized tendency in Magnoliaceae, which confirms the derived position of W. septentrionalis in this family. As the initiation pattern of floral parts of W. septentrionalis is very similar to other species in this family, it needs further investigation and especially comparison with species in Kmeria to evaluate the separation of Woonyoungia.

  13. Intestinal parasites of unisexual and bisexual lizards Darevskia spp. (Lacertidae from Northeastern Anatolia

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    Roca V.

    2016-09-01

    Full Text Available Four bisexual and two unisexual species of the lizard genus Darevskia from northeastern Anatolia were searched for intestinal parasites in adult specimens. One cestode, Nematotaenia tarentolae, and two nematode species, Spauligodon saxicolae and Strongyloides darevskyi, were found, the latest identified as a Darevskia specialist. No major differences between host species were recorded. The very low infection rates and diversity result in depauperate helminth communities for all these lacertid lizards being the lowest among the Palaearctic saurians. Patterns of these helminth communities are compared with those observed in other lacertid lizards from Anatolia and Europe.

  14. The transcriptomes of the crucian carp complex (Carassius auratus) provide insights into the distinction between unisexual triploids and sexual diploids.

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    Li, Chun-Yan; Li, Jiong-Tang; Kuang, You-Yi; Xu, Ru; Zhao, Zi-Xia; Hou, Guang-Yuan; Liang, Hong-Wei; Sun, Xiao-Wen

    2014-05-27

    Both sexual reproduction and unisexual reproduction are adaptive strategies for species survival and evolution. Unisexual animals have originated largely by hybridization, which tends to elevate their heterozygosity. However, the extent of genetic diversity resulting from hybridization and the genomic differences that determine the type of reproduction are poorly understood. In Carassius auratus, sexual diploids and unisexual triploids coexist. These two forms are similar morphologically but differ markedly in their modes of reproduction. Investigation of their genomic differences will be useful to study genome diversity and the development of reproductive mode. We generated transcriptomes for the unisexual and sexual populations. Genes were identified using homology searches and an ab initio method. Estimation of the synonymous substitution rate in the orthologous pairs indicated that the hybridization of gibel carp occurred 2.2 million years ago. Microsatellite genotyping in each individual from the gibel carp population indicated that most gibel carp genes were not tri-allelic. Molecular function and pathway comparisons suggested few gene expansions between them, except for the progesterone-mediated oocyte maturation pathway, which is enriched in gibel carp. Differential expression analysis identified highly expressed genes in gibel carp. The transcriptomes provide information on genetic diversity and genomic differences, which should assist future studies in functional genomics.

  15. The Transcriptomes of the Crucian Carp Complex (Carassius auratus Provide Insights into the Distinction between Unisexual Triploids and Sexual Diploids

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    Chun-Yan Li

    2014-05-01

    Full Text Available Both sexual reproduction and unisexual reproduction are adaptive strategies for species survival and evolution. Unisexual animals have originated largely by hybridization, which tends to elevate their heterozygosity. However, the extent of genetic diversity resulting from hybridization and the genomic differences that determine the type of reproduction are poorly understood. In Carassius auratus, sexual diploids and unisexual triploids coexist. These two forms are similar morphologically but differ markedly in their modes of reproduction. Investigation of their genomic differences will be useful to study genome diversity and the development of reproductive mode. We generated transcriptomes for the unisexual and sexual populations. Genes were identified using homology searches and an ab initio method. Estimation of the synonymous substitution rate in the orthologous pairs indicated that the hybridization of gibel carp occurred 2.2 million years ago. Microsatellite genotyping in each individual from the gibel carp population indicated that most gibel carp genes were not tri-allelic. Molecular function and pathway comparisons suggested few gene expansions between them, except for the progesterone-mediated oocyte maturation pathway, which is enriched in gibel carp. Differential expression analysis identified highly expressed genes in gibel carp. The transcriptomes provide information on genetic diversity and genomic differences, which should assist future studies in functional genomics.

  16. The occurrence of spermatozoa in the ovary of the gynogenetic viviparous teleost Poecilia formosa (POECILIIDAE).

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    Uribe, Mari Carmen; Grier, Harry J; De la Rosa-Cruz, Gabino; Schartl, Manfred

    2016-03-01

    The reproductive mode of the female viviparous teleost Poecilia formosa (Poeciliidae) represents the phenomenon known as gynogenesis; that is, parthenogenetic development is initiated by spermatozoa which are needed for physiological activation of the egg and the initiation of gestation, but spermatozoa are prevented from contributing to the genome of the embryo. For the reason that no previous histological analyses of the ovary of this species during the reproductive cycle has been published the present study has been conducted. This study examined the histology of the ovary of P. formosa during nongestation and gestation phases and identified the presence of spermatozoa inside the ovary. Spermatozoa were observed in folds of the ovarian epithelium of P. formosa during both the nongestation and gestation phases. Sperm storage as documented in this study is a very important trait for the gynogenetic viviparous fish P. formosa contributing to the understanding of this species reproduction.

  17. Discovery of a male-biased mutant family and identification of a male-specific SCAR marker in gynogenetic gibel carp Carassius auratus gibelio

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    Da Wang; Huiling Mao; Jinxia Peng; Xiyin Li; Li Zhou; Jianfang Gui

    2009-01-01

    Gibel carp (Carassius auratus gibelio) is a uniquely gynogenetic species with a minor ratio of males in natural habitats, but its male origin and sex determination mechanisms have been unknown. In this study, a male-biased mutant family was discovered from the gynogenetic gibel carp, and a male-specific SCAR marker was identified from the mutant family. Normal spermatogenesis was observed in the male testes by immunofluorescence histochemistry. Nearly identical AFLP profiles were observed between males and females, but a male-specific 86 bp AFLP fragment was screened by sex-pool bulked segregant analysis and individual screening. Based on the male-specific AFLP frag-ment, a total of 579 bp sequences were cloned by genome walking. Subsequently, a male-specific SCAR marker was designed, and the male-specific DNA fragment was confirmed to be steadily transmitted to the next generation and consistently detected only in males.

  18. Unisexual reproduction enhances fungal competitiveness by promoting habitat exploration via hyphal growth and sporulation.

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    Phadke, Sujal S; Feretzaki, Marianna; Heitman, Joseph

    2013-08-01

    Unisexual reproduction is a novel homothallic sexual cycle recently discovered in both ascomycetous and basidiomycetous pathogenic fungi. It is a form of selfing that induces the yeast-to-hyphal dimorphic transition in isolates of the α mating type of the human fungal pathogen Cryptococcus neoformans. Unisexual reproduction may benefit the pathogen by facilitating sexual reproduction in the absence of the opposite a mating type and by generating infectious propagules called basidiospores. Here, we report an independent potential selective advantage of unisexual reproduction beyond genetic exchange and recombination. We competed a wild-type strain capable of undergoing unisexual reproduction with mutants defective in this developmental pathway and found that unisexual reproduction provides a considerable dispersal advantage through hyphal growth and sporulation. Our results show that unisexual reproduction may serve to facilitate access to both nutrients and potential mating partners and may provide a means to maintain the capacity for dimorphic transitions in the environment.

  19. The quest for epigenetic regulation underlying unisexual flower development in Cucumis melo

    KAUST Repository

    Latrasse, David

    2017-05-08

    BackgroundMelon (Cucumis melo) is an important vegetable crop from the Cucurbitaceae family and a reference model specie for sex determination, fruit ripening and vascular fluxes studies. Nevertheless, the nature and role of its epigenome in gene expression regulation and more specifically in sex determination remains largely unknown.ResultsWe have investigated genome wide H3K27me3 and H3K9ac histone modifications and gene expression dynamics, in five melon organs. H3K9ac and H3K27me3 were mainly distributed along gene-rich regions and constrained to gene bodies. H3K9ac was preferentially located at the TSS, whereas H3K27me3 distributed uniformly from TSS to TES. As observed in other species, H3K9ac and H3K27me3 correlated with high and low gene expression levels, respectively. Comparative analyses of unisexual flowers pointed out sex-specific epigenetic states of TFs involved in ethylene response and flower development. Chip-qPCR analysis of laser dissected carpel and stamina primordia, revealed sex-specific histone modification of MADS-box genes. Using sex transition mutants, we demonstrated that the female promoting gene, CmACS11, represses the expression of the male promoting gene CmWIP1 via deposition of H3K27me3.ConclusionsOur findings reveal the organ-specific landscapes of H3K9ac and H3K27me3 in melon. Our results also provide evidence that the sex determination genes recruit histone modifiers to orchestrate unisexual flower development in monoecious species.

  20. Photographic evidence of interspecies mating in geckos of the Lepidodactylus lugubris unisexual-bisexual complex (Squamata: Gekkonidae)

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    Buden, Donald W.; Cianchini, Carlos; Taborosi, Danko; Fisher, Robert N.; Bauer, Aaron; Ineich, Ivan

    2014-01-01

    An interspecies mating between unisexual Lepidodactylus lugubris and a male of the bisexual Lepidodactylus moestus was photographed by Carlos Cianchini on Kosrae [Island], FSM, at 18:15 h on 22 August 2013 (Figure 1). The mating pair was on a window frame inside a house at Pukusruk Wan village (05°21'01" N, 163°00'41" E, elev. 28 m a.s.l.) on the northeastern side of the island. This is the first direct evidence of mating between these two species.

  1. Establishment of the diploid gynogenetic hybrid clonal line of red crucian carp × common carp

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    LIU ShaoJun; DUAN Wei; TAO Min; ZHANG Chun; SUN YuanDong; SHEN JiaMin; WANG Jing; LUO KaiKun; LIU Yun

    2007-01-01

    This study investigated the gynogenetic cytobiological behavior of the third gynogenetic generation (G3), which was generated from the diploid eggs produced by the second gynogenetic generation (G2)of red crucian carp × common carp, and determined the chromosomal numbers of G3, G2×scatter scale carp and G2×allotetraploid hybrids of red crucian carp × common carp. The results showed that the diploid eggs of G2 with 100 chromosomes, activated by UV-irradiated sperm from scatter scale carp and without the treatment for doubling the chromosomes, could develop into G3 with 100 chromosomes.Similar to the first and second gynogenetic generations (G1 and G2), G3 was also diploid (2n=100) and presented the hybrid traits. The triploids (3n=150) and tetraploids (4n=200) were produced by crossing G2 with scatter scale carp, and crossing G2 with allotetraploids, respectively. The extrusion of the second polar body in the eggs of G2 ruled out the possibility that the retention of the second polar body led to the formation of the diploid eggs. In addition, we discussed the mechanism of the formation of the diploid eggs generated by G2. The establishment of the diploid gynogenesis clonal line (G1, G2 and G3) provided the evidence that the diploid eggs were able to develop into a new diploid hybrid clonal line by gynogenesis. By producing the diploid eggs as a unique reproductive way, the diploid gynogenetic progeny of allotetrapioid hybrids of red crucian carp × common carp had important significances in both biological evolution and production application.

  2. Establishment of the diploid gynogenetic hybrid clonal line of red crucian carp × common carp

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    This study investigated the gynogenetic cytobiological behavior of the third gynogenetic generation (G3), which was generated from the diploid eggs produced by the second gynogenetic generation (G2) of red crucian carp × common carp, and determined the chromosomal numbers of G3, G2×scatter scale carp and G2×allotetraploid hybrids of red crucian carp × common carp. The results showed that the diploid eggs of G2 with 100 chromosomes, activated by UV-irradiated sperm from scatter scale carp and without the treatment for doubling the chromosomes, could develop into G3 with 100 chromosomes. Similar to the first and second gynogenetic generations (G1 and G2), G3 was also diploid (2n=100) and presented the hybrid traits. The triploids (3n=150) and tetraploids (4n=200) were produced by crossing G2 with scatter scale carp and crossing G2 with allotetraploids, respectively. The extrusion of the second polar body in the eggs of G2 ruled out the possibility that the retention of the second polar body led to the formation of the diploid eggs. In addition, we discussed the mechanism of the formation of the diploid eggs generated by G2. The establishment of the diploid gynogenesis clonal line (G1, G2 and G3) provided the evidence that the diploid eggs were able to develop into a new diploid hybrid clonal line by gynogenesis. By producing the diploid eggs as a unique reproductive way, the diploid gyno- genetic progeny of allotetraploid hybrids of red crucian carp × common carp had important signifi- cances in both biological evolution and production application.

  3. Microsatellite-centromere mapping in Japanese scallop ( Patinopecten yessoensis) through half-tetrad analysis in gynogenetic diploid families

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    Li, Qi; Qi, Mingjun; Nie, Hongtao; Kong, Lingfeng; Yu, Hong

    2016-06-01

    Gene-centromere mapping is an essential prerequisite for understanding the composition and structure of genomes. Half-tetrad analysis is a powerful tool for mapping genes and understanding chromosomal behavior during meiosis. The Japanese scallop ( Patinopecten yessoensis), a cold-tolerant species inhabiting the northwestern Pacific coast, is a commercially important marine bivalve in Asian countries. In this study, inheritance of 32 informative microsatellite loci was examined in 70-h D-shaped larvae of three induced meiogynogenetic diploid families of P. yessoensis for centromere mapping using half-tetrad analysis. The ratio of gynogenetic diploids was proven to be 100%, 100% and 96% in the three families, respectively. Inheritance analysis in the control crosses showed that 51 of the 53 genotypic ratios observed were in accordance with Mendelian expectations at the 5% level after Bonferroni correction. Seven of the 32 microsatellite loci showed the existence of null alleles in control crosses. The second division segregation frequency ( y) of the microsatellite loci ranged from 0.07 to 0.85 with a mean of 0.38, suggesting the existence of positive interference after a single chiasma formation in some chromosomes in the scallop. Microsatellite-centromere distances ranged from 4 cM to 42 cM under the assumption of complete interference. Information on the positions of centromeres in relation to the microsatellite loci will represent a contribution towards the assembly of genetic maps in the commercially important scallop species.

  4. Genetic circuits that govern bisexual and unisexual reproduction in Cryptococcus neoformans.

    Directory of Open Access Journals (Sweden)

    Marianna Feretzaki

    Full Text Available Cryptococcus neoformans is a human fungal pathogen with a defined sexual cycle. Nutrient-limiting conditions and pheromones induce a dimorphic transition from unicellular yeast to multicellular hyphae and the production of infectious spores. Sexual reproduction involves cells of either opposite (bisexual or one (unisexual mating type. Bisexual and unisexual reproduction are governed by shared components of the conserved pheromone-sensing Cpk1 MAPK signal transduction cascade and by Mat2, the major transcriptional regulator of the pathway. However, the downstream targets of the pathway are largely unknown, and homology-based approaches have failed to yield downstream transcriptional regulators or other targets. In this study, we applied insertional mutagenesis via Agrobacterium tumefaciens transkingdom DNA delivery to identify mutants with unisexual reproduction defects. In addition to elements known to be involved in sexual development (Crg1, Ste7, Mat2, and Znf2, three key regulators of sexual development were identified by our screen: Znf3, Spo11, and Ubc5. Spo11 and Ubc5 promote sporulation during both bisexual and unisexual reproduction. Genetic and phenotypic analyses provide further evidence implicating both genes in the regulation of meiosis. Phenotypic analysis of sexual development showed that Znf3 is required for hyphal development during unisexual reproduction and also plays a central role during bisexual reproduction. Znf3 promotes cell fusion and pheromone production through a pathway parallel to and independent of the pheromone signaling cascade. Surprisingly, Znf3 participates in transposon silencing during unisexual reproduction and may serve as a link between RNAi silencing and sexual development. Our studies illustrate the power of unbiased genetic screens to reveal both novel and conserved circuits that operate sexual reproduction.

  5. Comparative investigation on spindle behavior and MPF activity changes during oocyte maturation between gynogenetic and amphimictic crucian carp

    Institute of Scientific and Technical Information of China (English)

    YANGZHONGAN; QUNHUALI; 等

    1999-01-01

    The spindle behavior and MPF activity changes in the progression of oocyte maturation were investigated and compared with cytological observation and kinase assay between gynogenetic silver crucian carp and amphimictic colored crucian carp.MPF activity was measured by using histone H1 as phosphorylation substrate.There were two similar oscillatory MPF kinase activity changes during oocyte maturation in two kinds of fishes with different reproductive modes,but there existed some subtle difference between them.The subtle difference was that the first peak of MPF kinase activity was kept to a longerlasting time in the gynogenetic silver crucian carp than in the amphimictic colored crucian carp.It was suggested that the difference may be related to the spindle behavior changes,such as tripolar spindle formation and spindle rearrangement in the gynogenetic crucian carp.

  6. Artificial induction of mito-gynogenetic diploids in large yellow croaker ( Pseudosciaena crocea) by hydrostatic pressure

    Science.gov (United States)

    Cai, Mingyi; Wu, Qingming; Liu, Xiande; Yao, Cuiluan; Chen, Qingkai; Wang, Zhiyong

    2010-07-01

    The present study investigated conditions for inducing mito-gynogenetic (endomitosis) diploids by hydrostatic pressure in the large yellow croaker Pseudosciaena crocea. In haploid control groups, the development of eggs was activated with ultraviolet radiated semen. All fry presented typical haploid syndrome in the haploid control groups, and were verified as haploids using cytometry. After hydrostatic pressure treatment, morphologically normal fry reappeared at different frequencies according to the intensity and time of pressure shock. Fry with normal appearance in the pressure treated groups were verified as gynogenetic double haploids (GDHs), containing only one allele from the female parent at all four diagnostic microsatellite loci. For a fixed duration of 3 min, the optimal intensity of blocking the first mitosis was determined to be 40 Mpa, which was similar to that of blocking the second meiosis. There was a “window” of starting time, from 36.1 min to 38.1 min post-insemination at 25.0±1.0°C, within which the production of GDHs was not significantly different. Maximum production of morphologically normal fries, 9.36%±2.97% of developed eggs, was found when the eggs were shocked with hydrostatic pressure at 40 Mpa for 3 min, starting from 38.1 min post insemination at 25.0±1.0°C.

  7. Progress on sex differentiation in unisexual flower plants%单性花植物性别分化研究进展

    Institute of Scientific and Technical Information of China (English)

    高暝; 陈益存; 杨素素; 刘英冠; 朱慧萍; 汪阳东

    2015-01-01

    segregation of sexual phenotypes by preventing the recombination of sex determining genes;epigenetic regulatory mechanism,which alter gene expression,and hormonal regulation in Z .mays and Cucumis sativus .Sex determination is generally regulated by interactions between hormones,genetics and epigenetic modification.However,many important questions remain to be an-swered on the regulatory mechanisms of sex determination and sex differentiation,for example why few sex de-termination genes have been cloned,why the proportion of species with sex chromosomes is low,the relatively small portion of the dioecious species that have sex chromosomes,and the major epigenetic maintainers in gen-otypic sex determination (GSD).The recent research aimed at understanding the regulatory mechanisms of sex determination and sex differentiation in unisexual flowers,including phenotype traits,genetic base,epigenetics and physiological mechanisms were reviewed in this paper.Challenges and strategies are proposed to provide an effective contribution to elucidate the regulatory mechanisms of sex determination and sex differentiation in plants.

  8. STUDY ON EMBRYONIC DEVELOPMENT AND EARLY GROWTH OF TRIPLOID AND GYNOGENETIC DIPLOID LEFT-EYED FLOUNDER, PARALICHTHYS OLIVACEUS(T. et S.)

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The early effects of chromosomal manipulation of eggs and sperm on the yields of triploid and gynogenetic diploid larvae of Paralichthys olivaceus were investigated. Triploidy was achieved by cold shocking fertilized eggs at 0-2℃ for 45 minutes duration 5 minutes after fertilization, and the induced triploidy rates were 31.2%-50% and the relative hatching rates were 53.3%-99%. Gynogenetic diploids were obtained when eggs were inseminated with irradiated sperm and cold shocked at 0-2℃ for 45 minutes duration 5 minutes after fertilization. The induced gynogenetic diploid rates and the relative hatching rates were 94%-96% and 48.5%-68.5% respectively. The embryonic development of the triploid experimental group and of the gynogenetic diploid experimental group was delayed at first compared with the control group. But from the gastrula stage, it was not delayed anymore. There were no significant differences in the growth of the triploid experimental group larvae and the control group larvae, and in the growth of the gynogenetic diploid experimental group larvae and the control group larvae according to Student's t-test (α=0.05). The relationship between the early growth of the triploid experimental group larvae and that of gynogenetic diploid experimental group larvae was also studied.

  9. Comparative studies on in vitro sperm decondensation and pronucleus formation in egg extracts between gynogenetic and bisexual fish

    Institute of Scientific and Technical Information of China (English)

    CHANG JIAN LI; JIAN FANG GUI

    2003-01-01

    A cell-free system based upon the egg extracts from gynogenetic gibel carp (Carassius auratus gibelio)or bisexual red common carp (Cyprinus carpio red variety) was developed to investigate developmentalbehaviors of the demembranated sperm nuclei. Both red common carp and gibel carp sperm nuclei coulddecondense fully and form pronuclei in the red common carp egg extracts. Gibel carp sperm nuclei couldalso decondense fully and form pronuclei in the gibel carp egg extracts, but red common carp sperm nucleicould not decondense sufficiently in the same extracts. The significant differences of morphological changeswere further confirmed by ultrastructural observation of transmission electron microscopy. The data furtheroffer cytological evidence for gonochoristic reproduction in the gynogenetically reproducing gibel carp. Inaddition, the sperm nuclei in vitro decondensation is dependent on the pH in the extracts, and the decon-densed efficiency is optimal at pH 7. However, no DNA replication was observed in the two kinds of eggextracts during the incubation period of the sperm nuclei. It is suggested that the egg extracts preparedfrom the gynogenetic gibel carp should be a valid in vitro system for studying molecular mechanism ongynogenesis and reproduction mode diversity in fish.

  10. Sperm nuclear expansion and meiotic maturation in normal and gynogenetic eggs of the scallop, Chlamys farreri

    Science.gov (United States)

    Pan, Ying; Li, Qi; Yu, Ruihai; Wang, Rucai

    2008-02-01

    Sperm nuclear expansion, meiosis and the association of the male and female pronuclei leading to the four-cell stage in normal Chlamys farreri eggs were observed under a fluorescence microscope. The effects of ultraviolet (UV) irradiation on the fertilizing sperm were also examined. Both normal and UV-irradiated sperm nuclei enlarged at three distinct phases (phase A, metaphase I; phase B, polar body formation; and phase C, female pronuclear development and expansion) that were temporally correlated with meiotic process of the maternal chromosomes. Sperm nuclei underwent a rapid, initial enlargement during phase A, but condensed slightly during phase B, then re-enlarged during phase C. The effects of UV irradiation were not apparent during transformation of the sperm nucleus into a male pronucleus, and there was not any apparent effect on meiotic maturation and development of the female pronucleus. However, the rate of expansion of the UV-irradiated sperm nuclei and the size of male pronuclei were reduced apparently. Unlike the female pronucleus, the male pronucleus derived from sperm genome inactivated by UV irradiation did not form chromosomes, but became a dense chromatin body (DCB). At mitotic anaphase, DCB did not participate in the karyokinesis of the first cleavage as evidenced by chromosomal nondisjunction, demonstrating the effectiveness of using UV irradiation to induce gynogenetic scallop embryos.

  11. Sperm Nuclear Expansion and Meiotic Maturation in Normal and Gynogenetic Eggs of the Scallop, Chlamys farreri

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Sperm nuclear expansion, meiosis and the association of the male and female pronuclei leading to the four-cell stage in normal Chlamys farreri eggs were observed under a fluorescence microscope. The effects of ultraviolet (UV) irradiation on the fertilizing sperm were also examined. Both normal and UV-irradiated sperm nuclei enlarged at three distinct phases (phase A, metaphase Ⅰ; phase B, polar body formation; and phase C, female pronuclear development and expansion) that were temporally correlated with meiotic process of the maternal chromosomes. Sperm nuclei underwent a rapid, initial enlargement during phase A, but condensed slightly during phase B, then re-enlarged during phase C. The effects of UV irradiation were not apparent during transformation of the sperm nucleus into a male pronucleus, and there was not any apparent effect on meiotic maturation and development of the female pronucleus. However, the rate of expansion of the UV-irradiated sperm nuclei and the size of male pronuclei were reduced apparently. Unlike the female pronucleus, the male pronucleus derived from sperm genome inactivated by UV irradiation did not form chromosomes, but became a dense chromatin body (DCB). At mitotic anaphase, DCB did not participate in the karyokinesis of the first cleavage as evidenced by chromosomal nondisjunction, demonstrating the effectiveness of using UV irradiation to induce gynogenetic scallop embryos.

  12. STUDY ON EMBRYONIC DEVELOPMENT AND EARLY GROWTH OF TRIPLOID AND GYNOGENETIC DIPLOID LEFI—EYED FLOUNDER, PARALICHTHYS OLIVACEUS (T. et S. )

    Institute of Scientific and Technical Information of China (English)

    尤锋; 刘静; 王新成; 徐永立; 黄瑞东; 张培军

    2001-01-01

    The early effects of chromosomal manipulation of eggs and sperm on the yields of trip-loid and gynogenefic diploid larvae of Paralichthys olivaceus were investigated. Triploidy was achieved by cold shocking fen.ilized eggs at 0 - 2℃ for 45 minutes duration 5 minutes after fen.ilization, and the in-duced triploidy rates were 31.2% - 50% and the relative hatching rates were 53.3% - 99%. Gynnge-aetic diploids were obtained when eggs were inseminated with irradiated sperm and cold shocked at 0 -2℃ for 45 minutes duration 5 minutes after fertihzation. The induced gynogenetic diploid rates and the relative hatching rates were 94 % - 96 % and 48.5 % - 68.5 % respectively. The embryonic development of the triploid experimental group and of the gynogenetic diploid experimental group was delayed at first compared with the control group. But from the gastrula stage, it was not delayed anymore. There were no significant differences in the growth of the triploid experimental group larvae and the control group larvae, and in the growth of the gynogenetic diploid experimental group larvae and the control group larvae ac-cording to Student's t-test (α = 0.05). The relationship between the early growth of the triploid experi-mental group larvae and that of gynogenetic diploid experimental group larvae was also studied.

  13. Unisexual and heterosexual meiotic reproduction generate aneuploidy and phenotypic diversity de novo in the yeast Cryptococcus neoformans.

    Directory of Open Access Journals (Sweden)

    Min Ni

    2013-09-01

    Full Text Available Aneuploidy is known to be deleterious and underlies several common human diseases, including cancer and genetic disorders such as trisomy 21 in Down's syndrome. In contrast, aneuploidy can also be advantageous and in fungi confers antifungal drug resistance and enables rapid adaptive evolution. We report here that sexual reproduction generates phenotypic and genotypic diversity in the human pathogenic yeast Cryptococcus neoformans, which is globally distributed and commonly infects individuals with compromised immunity, such as HIV/AIDS patients, causing life-threatening meningoencephalitis. C. neoformans has a defined a-α opposite sexual cycle; however, >99% of isolates are of the α mating type. Interestingly, α cells can undergo α-α unisexual reproduction, even involving genotypically identical cells. A central question is: Why would cells mate with themselves given that sex is costly and typically serves to admix preexisting genetic diversity from genetically divergent parents? In this study, we demonstrate that α-α unisexual reproduction frequently generates phenotypic diversity, and the majority of these variant progeny are aneuploid. Aneuploidy is responsible for the observed phenotypic changes, as chromosome loss restoring euploidy results in a wild-type phenotype. Other genetic changes, including diploidization, chromosome length polymorphisms, SNPs, and indels, were also generated. Phenotypic/genotypic changes were not observed following asexual mitotic reproduction. Aneuploidy was also detected in progeny from a-α opposite-sex congenic mating; thus, both homothallic and heterothallic sexual reproduction can generate phenotypic diversity de novo. Our study suggests that the ability to undergo unisexual reproduction may be an evolutionary strategy for eukaryotic microbial pathogens, enabling de novo genotypic and phenotypic plasticity and facilitating rapid adaptation to novel environments.

  14. Sequence Evolution and Expression of the Androgen Receptor and Other Pathway-Related Genes in a Unisexual Fish, the Amazon Molly, Poecilia formosa, and Its Bisexual Ancestors

    Science.gov (United States)

    Zhu, Fangjun; Schlupp, Ingo; Tiedemann, Ralph

    2016-01-01

    The all-female Amazon molly (Poecilia formosa) originated from a single hybridization of two bisexual ancestors, Atlantic molly (Poecilia mexicana) and sailfin molly (Poecilia latipinna). As a gynogenetic species, the Amazon molly needs to copulate with a heterospecific male, but the genetic information of the sperm-donor does not contribute to the next generation, as the sperm only acts as the trigger for the diploid eggs’ embryogenesis. Here, we study the sequence evolution and gene expression of the duplicated genes coding for androgen receptors (ars) and other pathway-related genes, i.e., the estrogen receptors (ers) and cytochrome P450, family19, subfamily A, aromatase genes (cyp19as), in the Amazon molly, in comparison to its bisexual ancestors. Mollies possess–as most other teleost fish—two copies of the ar, er, and cyp19a genes, i.e., arα/arβ, erα/erβ1, and cyp19a1 (also referred as cyp19a1a)/cyp19a2 (also referred to as cyp19a1b), respectively. Non-synonymous single nucleotide polymorphisms (SNPs) among the ancestral bisexual species were generally predicted not to alter protein function. Some derived substitutions in the P. mexicana and one in P. formosa are predicted to impact protein function. We also describe the gene expression pattern of the ars and pathway-related genes in various tissues (i.e., brain, gill, and ovary) and provide SNP markers for allele specific expression research. As a general tendency, the levels of gene expression were lowest in gill and highest in ovarian tissues, while expression levels in the brain were intermediate in most cases. Expression levels in P. formosa were conserved where expression did not differ between the two bisexual ancestors. In those cases where gene expression levels significantly differed between the bisexual species, P. formosa expression was always comparable to the higher expression level among the two ancestors. Interestingly, erβ1 was expressed neither in brain nor in gill in the analyzed

  15. Sequence Evolution and Expression of the Androgen Receptor and Other Pathway-Related Genes in a Unisexual Fish, the Amazon Molly, Poecilia formosa, and Its Bisexual Ancestors.

    Directory of Open Access Journals (Sweden)

    Fangjun Zhu

    Full Text Available The all-female Amazon molly (Poecilia formosa originated from a single hybridization of two bisexual ancestors, Atlantic molly (Poecilia mexicana and sailfin molly (Poecilia latipinna. As a gynogenetic species, the Amazon molly needs to copulate with a heterospecific male, but the genetic information of the sperm-donor does not contribute to the next generation, as the sperm only acts as the trigger for the diploid eggs' embryogenesis. Here, we study the sequence evolution and gene expression of the duplicated genes coding for androgen receptors (ars and other pathway-related genes, i.e., the estrogen receptors (ers and cytochrome P450, family19, subfamily A, aromatase genes (cyp19as, in the Amazon molly, in comparison to its bisexual ancestors. Mollies possess-as most other teleost fish-two copies of the ar, er, and cyp19a genes, i.e., arα/arβ, erα/erβ1, and cyp19a1 (also referred as cyp19a1a/cyp19a2 (also referred to as cyp19a1b, respectively. Non-synonymous single nucleotide polymorphisms (SNPs among the ancestral bisexual species were generally predicted not to alter protein function. Some derived substitutions in the P. mexicana and one in P. formosa are predicted to impact protein function. We also describe the gene expression pattern of the ars and pathway-related genes in various tissues (i.e., brain, gill, and ovary and provide SNP markers for allele specific expression research. As a general tendency, the levels of gene expression were lowest in gill and highest in ovarian tissues, while expression levels in the brain were intermediate in most cases. Expression levels in P. formosa were conserved where expression did not differ between the two bisexual ancestors. In those cases where gene expression levels significantly differed between the bisexual species, P. formosa expression was always comparable to the higher expression level among the two ancestors. Interestingly, erβ1 was expressed neither in brain nor in gill in the

  16. The gynogenetic reproduction of diploid and triploid hybrid spined loaches (Cobitis: Teleostei), and their ability to establish successful clonal lineages--on the evolution of polyploidy in asexual vertebrates.

    Science.gov (United States)

    Janko, Karel; Bohlen, Jörg; Lamatsch, Dunja; Flajshans, Martin; Epplen, Jörg T; Ráb, Petr; Kotlík, Petr; Slechtová, Vera

    2007-10-01

    Polyploidisation is assumed to have played a significant role in the evolution of hybrid asexual lineages. The virtual absence of natural asexual systems in which more than a single ploidy level successfully establishes successful independent clonal lineages is generally explained by the strong effects of polyploidisation on fitness. Experimental crosses were made between diploid and triploid asexual Cobitis elongatoides x C. taenia hybrids (female) and both parental spined loach species (male). Genotyping of the progeny using allozymes and multilocus DNA fingerprinting, along with flow cytometric measurement of ploidy level, demonstrated the occurrence of gynogenetic reproduction in both female biotypes. The incorporation of the sperm genome occurred in some progeny, giving rise to a higher ploidy level, but the rate of polyploidisation differed significantly between the diploid and triploid females. These outcomes are consistent with the existence of developmental constraints on tetraploidy, which determine the rarity of tetraploids in natural populations. No cases of ploidy level reduction were observed. Since diploid and triploid hybrid populations occur where the lack of potential progenitor excludes the possibility of de novo origin, it is probable that both diploid and triploid females can establish successful clonal lineages. Spined loaches represent a unique example, among asexual vertebrates, where more than one ploidy level can establish persistent clonal lineages, which are reproductively independent of one another.

  17. Genetic discrimination for three gynogenetic clones of silver carp Hypophthalmichthys molitrix, based on restriction endonuclease analysis of Nd5-Nd6 region of mitochondrial DNA

    Institute of Scientific and Technical Information of China (English)

    ZHOU Jianfeng; YE Yuzhen; WU Qingjiang

    2005-01-01

    Three artificial gynogenetic clones of silver carp were produced for the analysis of restriction enzyme digestion patterns of ND5-ND6 region from mtDNA of the clones. It is revealed that all intraclonal individuals shared completely the same digestion patterns but among interclonal individuals did not. The three clones were mixed and cultured in a pond together for two years, and restriction endonuclease digestion patterns of ND5-ND6 were used as genetic markers to assess the growth performance of each clone.

  18. Screen for stage-specific expression genes between tail bud stage and heartbeat beginning stage in embryogenesis of gynogenetic silver crucian carp

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    A systemic study was initiated to identify stage-specific expression genes in fish embryogenesis by using suppression subtractive hybridization (SSH) technique. In this study, we presented a preliminary result on screen for stage-specific expression genes between tail bud stage (TBS) and heartbeat beginning stage (HBS) in gynogenetic silver crucian carp (Carassius auratus gibelio). Two SSH plasmid libraries specific for TBS embryos and HBS embryos were constructed, and stage-specific expression genes were screened between the two stages. 1963 TBS positive clones and 2466 HBS positive clones were sampled to PCR amplification, and 1373 TBS and 1809 HBS PCR positive clones were selected to carry out dot blots. 169TBS dot blot positive clones and 272 HBS dot blot positive clones were sequenced. Searching GenBank by using these nucleotide sequences indicated that most of the TBS dot blot positive clones could not be found homologous sequences in the database, while known genes were mainly detected from HBS dot blot positive clones. Of the 79 known genes, 20 were enzymes or kinases involved in important metabolism of embryonic development. Moreover, specific expressions of partial genes were further confirmed by virtual northern blots. This study is the first step for making a large attempt to study temporal and spatial control f gene expression in the gynogenetic fish embryogenesis.

  19. Differential screening and characterization analysis of the egg envelope glycoprotein ZP3 cDNAs between gynogenetic and gonochoristic crucian carp

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Gynogenetic silver crucian carp,Carassius auratus gibelio,is an intriguing model system.In the present work,a systemic study has been initiated by introducing suppression subtractive hybridization technique into this model system to identify the differentially expressed genes in oocytes between gynogenetic silver crucian carp and its closely related gonochoristic color crucian carp.Five differential cDNA fragments were identified from the preliminary screening,and two of them are ZP3 homologues.Moreover,the full length ZP3 cDNAs were cloned from their oocyte cDNA libraries.The length of ZP3 cDNAs were 1378 bp for gyno-carp and 1367 bp for gono-carp,and they can be translated into proteins with 435 amino acids.Obvious differences are not only in the composition of amino acids,but also in the number of potential O-linked oligosaccharide sites.In addition,gyno-carp ZP3 amino acid sequence has an unexpected higher identity value with common carp (83.5%) than that with the closely related gono-carp (74.7%).The unique homology may be originated from the ancient hybridization.Northern blot analysis confirmed that expression of the ZP3 gene occurred exclusively in the oocytes.Because O-linked oligosaccharides on ZP3 have been demonstrated to play very important roles in fertilization,it is suggested that the extra O-linked glycosylation sites may be related to the unique sperm-egg recognition mechanism in gynogenesis.

  20. Coexistence of bisexual and unisexual populations of Nysius groenlandicus in the Zackenberg Valley, Northeast Greenland

    DEFF Research Database (Denmark)

    Bøcher, Jens Jensenius; Nachman, Gøsta Støger

    2011-01-01

    that the species has developed physiological, ecological, and behavioral mechanisms that enable it to cope with the extreme arctic environment.One of these adaptations is its ability to reproduce both sexually and asexually. Sexual reproduction is most common in coastal populations, whereas asexual reproduction...... in the more homogeneous areas along the coast. Data support the hypothesis that coexistence of the two reproductive types ismaintained by a combination of environmental variability, which gives sexual reproduction an advantage, and metapopulation dynamics characterized by frequent extinctions and re...

  1. Numerical and structural chromosome polimorphism in fish species: Carassius auratus gibelio b. and alburnus alburnus L.

    Directory of Open Access Journals (Sweden)

    Fišter Svetlana L.

    2003-01-01

    Full Text Available The paper presents the results of cytogenetic investigations of the fish species Carassius auratus gibelio, B. and Alburnus alburnus, L. Karyotype definitions are given for fish caught at different localities in Serbia. Within the bisexual population of the silver carp Carassius auratus gibelio B., we observed variability in the number of the last, smallest akrocentrics (2n=100_ 22-4. These variating accessory chromosomes were called Banalogues. We established the number of chromosomes (3n=150+8 and 3n=150+10 and gave the karyotype characteristics for gynogenetic lines of triploid females. We pointed out that the existing clones differ in the number of chromosomes, i.e. in the number of Banalogues, which are also probably the cause of the occurence of - gynogenetic karyoclones. In the species Alburnus alburnus, L., we established the existence of modified karyotipes with a large metacentric - Robertson's fusion, translocation probably formed by the two biggest akrocentrics. We examined the possibility of maintaining variability in populations of this specie. The results are discussed in comparison to disorders which result from these changes in reproduction, and the possible consequences that can be expected in the offispring.

  2. Morfologia e desenvolvimento de Schistosoma mansoni Sambon, 1907 em infecções unissexuais experimentalmente produzidas no camundongo Morphology and development of Schistosoma mansoni Sambon, 1907 in unisexual infections produced experimentally in mice

    Directory of Open Access Journals (Sweden)

    Eliana Maria Zanotti

    1982-04-01

    Full Text Available Estudou-se o desenvolvimento de Schistosoma mansoni em infecções unissexuais no camundongo. Os esquistossomos fêmeos apresentaram-se menos desenvolvidos do que os machos. Houve correlação entre o comprimento dos machos e o número de testículos. Verificou-se que o isolamento sexual é prejudicial aos dois sexos, principalmente à fêmea.The Schistosoma mansoni development in mice submitted to unisexual infections was studied. The single female worms developed less than the single males. There was correlation between the male's length and the number of his tests. It was verified that sexual isolation of the schistosomes is prejudicial to both sexes, mainly for the female.

  3. Hybridization leads to sensory repertoire expansion in a gynogenetic fish, the Amazon molly (poecilia formosa): a test of the hybrid-sensory expansion hypothesis.

    Science.gov (United States)

    Sandkam, Benjamin A; Joy, Jeffrey B; Watson, Corey T; Gonzalez-Bendiksen, Pablo; Gabor, Caitlin R; Breden, Felix

    2013-01-01

    Expansions in sensory systems usually require processes such as gene duplication and divergence, and thus evolve slowly. We evaluate a novel mechanism leading to rapid sensory repertoire expansion: hybrid-sensory expansion (HSE). HSE occurs when two species with differently tuned sensory systems form a hybrid, bringing together alleles from each of the parental species. In one generation, a sensory repertoire is created that is the sum of the variance between parental species. The Amazon molly presents a unique opportunity to test the HSE hypothesis in a "frozen" hybrid. We compared opsin sequences of the Amazon molly, Poecilia formosa, to those of the parental species. Both parental species are homozygous at the RH2-1 locus and each of the four long wavelength sensitive loci, while P. formosa possess two different alleles at these loci; one matching each parental allele. Gene expression analysis showed P. formosa use the expanded opsin repertoire that was the result of HSE. Additionally, behavioral tests revealed P. formosa respond to colored stimuli in a manner similar or intermediate to the parental species P. mexicana and P. latipinna. Together these results strongly support the HSE hypothesis. Hybrid-sensory repertoire expansion is likely important in other hybrid species and in other sensory systems.

  4. Monophyletic origin of multiple clonal lineages in an asexual fish (Poecilia formosa).

    Science.gov (United States)

    Stöck, Matthias; Lampert, Kathrin P; Möller, Dirk; Schlupp, Ingo; Schartl, Manfred

    2010-12-01

    Despite the advantage of avoiding the costs of sexual reproduction, asexual vertebrates are very rare and often considered evolutionarily disadvantaged when compared to sexual species. Asexual species, however, may have advantages when colonizing (new) habitats or competing with sexual counterparts. They are also evolutionary older than expected, leaving the question whether asexual vertebrates are not only rare because of their 'inferior' mode of reproduction but also because of other reasons. A paradigmatic model system is the unisexual Amazon molly, Poecilia formosa, that arose by hybridization of the Atlantic molly, Poecilia mexicana, as the maternal ancestor, and the sailfin molly, Poecilia latipinna, as the paternal ancestor. Our extensive crossing experiments failed to resynthesize asexually reproducing (gynogenetic) hybrids confirming results of previous studies. However, by producing diploid eggs, female F(1) -hybrids showed apparent preadaptation to gynogenesis. In a range-wide analysis of mitochondrial sequences, we examined the origin of P. formosa. Our analyses point to very few or even a single origin(s) of its lineage, which is estimated to be approximately 120,000 years old. A monophyletic origin was supported from nuclear microsatellite data. Furthermore, a considerable degree of genetic variation, apparent by high levels of clonal microsatellite diversity, was found. Our molecular phylogenetic evidence and the failure to resynthesize the gynogenetic P. formosa together with the old age of the species indicate that some unisexual vertebrates might be rare not because they suffer the long-term consequences of clonal reproduction but because they are only very rarely formed as a result of complex genetic preconditions necessary to produce viable and fertile clonal genomes and phenotypes ('rare formation hypothesis').

  5. Organization and variation analysis of 5S rDNA in gynogenetic offspring of Carassius auratus red var. (♀) × Megalobrama amblycephala (♂).

    Science.gov (United States)

    Qin, QinBo; Wang, Juan; Wang, YuDe; Liu, Yun; Liu, ShaoJun

    2015-03-13

    The offspring with 100 chromosomes (abbreviated as GRCC) have been obtained in the first generation of Carassius auratus red var. (abbreviated as RCC, 2n = 100) (♀) × Megalobrama amblycephala (abbreviated as BSB, 2n = 48) (♂), in which the females and unexpected males both are found. Chromosomal and karyotypic analysis has been reported in GRCC which gynogenesis origin has been suggested, but lack genetic evidence. Fluorescence in situ hybridization with species-specific centromere probes directly proves that GRCC possess two sets of RCC-derived chromosomes. Sequence analysis of the coding region (5S) and adjacent nontranscribed spacer (abbreviated as NTS) reveals that three types of 5S rDNA class (class I; class II and class III) in GRCC are completely inherited from their female parent (RCC), and show obvious base variations and insertions-deletions. Fluorescence in situ hybridization with the entire 5S rDNA probe reveals obvious chromosomal loci (class I and class II) variation in GRCC. This paper provides directly genetic evidence that GRCC is gynogenesis origin. In addition, our result is also reveals that distant hybridization inducing gynogenesis can lead to sequence and partial chromosomal loci of 5S rDNA gene obvious variation.

  6. Clutch size in populations and species of cnemidophorines (Squamata: Teiidae on the eastern coast of Brazil

    Directory of Open Access Journals (Sweden)

    VANDERLAINE A. MENEZES

    2014-06-01

    Full Text Available We analyzed some reproductive aspects of 16 coastal populations, belonging to five lizard species (A. ocellifera, A. abaetensis, A. nativo, A. littoralis and C. lacertoides from different restinga habitats along the eastern coast of Brazil. This study aimed to evaluate to what extent the reproductive aspects vary geographically and among species. For each female, we recorded the number of vitellogenic follicles, size and color of the largest follicle, presence and size of corpora lutea, and number and size of oviductal eggs. Clutch size of almost all coastal populations/species of Ameivula had little variation and most clutches were composed of two eggs. There was a significant relationship between female size and the mean clutch size when females from different species were pooled. Mean egg volume, among species, varied from 420 to 655 mm3. Relative clutch mass varied from 0.129 to 0.159 and did not differ significantly among species. We concluded that the five coastal species studied (four bisexuals and one parthenogenetic had similar reproductive characteristics. Most of them presented multiple clutches, low clutch size and low relative clutch mass, similar to other species in the genus and to unisexual and bisexual species of the Teiidae family.

  7. Ants with Attitude: Australian Jack-jumpers of the Myrmecia pilosula species complex, with descriptions of four new species (Hymenoptera: Formicidae: Myrmeciinae).

    Science.gov (United States)

    Taylor, Robert W

    2015-01-21

    The six known "Jack-jumper species Myrmecia pilosula Fr. Smith 1858, M. croslandi Taylor 1991, M. banksi, M. haskinsorum, M. imaii and M. impaternata spp.n. are reviewed, illustrated and keyed. Myrmecia imaii is known only from southwest Western Australia, the others variously from southeastern Australia and Tasmania. These taxa were previously confused under the name M. pilosula (for which a lectotype is designated). Previous cytogenetical findings, which contributed importantly to current taxonomic understanding, are summarized for each species. Eastern and Western geographical races of the widespread M. pilosula are recognized. Myrmecia croslandi is one of only two eukaryote animals known to possess a single pair of chromosomes (2n=2 3 or 4). Myrmecia impaternata is evidentially an allodiploid (n=5 or 14, 2n=19) sperm-dependent gynogenetic hybrid between M. banksi and an element of the eastern race of M. pilosula, or their immediate ancestry. The sting-injected venom of these ants can induce sometimes fatal anaphylaxis in sensitive humans. 

  8. 雌核发育二倍体鲫鲤及其他倍性鱼cdc2基因cDNA全序列克隆及表达%The cloning of cdc2 cDNAs and a comparative study of its expression in different ploidy fishes including the diploid gynogenetic hybrid of red crucian carp × common carp

    Institute of Scientific and Technical Information of China (English)

    陶敏; 刘少军; 钟欢; 周毅; 宋灿; 张纯; 刘筠

    2013-01-01

    Cdc2(Cyclin Dependent Kinase,namely CDK1)encoded by cdc2 gene and CyclinB combination regulates G2/M transition. To find out molecular mechanism that diploid hybrid fish could produce diploid gamete,the full length cDNAs of cdcl in the third gynogenetic generation(G3) ,red crucian carp( Carassius auratus red var. ) ,triploid crucian carp and allotetraploid were obtained by PCR and rapid amplification of cDNA ends. Our data showed that all the cDNAs of cdcl gene in the four different ploidy fishes encode a protein of 302 amino acids containing a domain (PSTAVRE) which combine Cyclins. A high homology of 97. 6% of the Cdc2 protein can be drawn by comparing the amino acid sequences in these four fishes, which indicates the higher conservative function and evolution of Cdc2 protein in these four fishes. A comparative expression pattern of cdcl in early-stage gonads of G3 and different ploidy fishes was carried out by Realtime PCR using specific primers against the same sequences of coding regions in the four fishes. The results showed that the expression of cdcl in the ovary of G3 was higher than those of red crucian carp and triploid crucian carp, while lower than that of allotetraploid, which, at the molecular level, indicates existence of polyploid oogonia in early-stage gonads of G3. The higher expression of cdcl in G3 suggests that consecutive S-phase replication may occur without intervening mitosis, which might be related to the formation mechanisms for the diploid eggs generated by diploid hybrids.%为研究雌核发育二倍体鲫鲤产生二倍体卵子的分子机制,实验采用PCR和cDNA末端快速分离法,克隆获得了雌核发育二倍体鲫鲤第三代(G3)、二倍体红鲫、三倍体湘云鲫和四倍体鲫鲤的细胞周期相关基因——cdc2基因cDNA全序列.结果显示,4种不同倍性鱼cdc2基因均编码含有302个氨基酸蛋白,而且编码的蛋白都含有与其他CDK激酶相当保守的序列PSTAVRE;同源性分析发现,4

  9. Species concepts and species delimitation.

    Science.gov (United States)

    De Queiroz, Kevin

    2007-12-01

    The issue of species delimitation has long been confused with that of species conceptualization, leading to a half century of controversy concerning both the definition of the species category and methods for inferring the boundaries and numbers of species. Alternative species concepts agree in treating existence as a separately evolving metapopulation lineage as the primary defining property of the species category, but they disagree in adopting different properties acquired by lineages during the course of divergence (e.g., intrinsic reproductive isolation, diagnosability, monophyly) as secondary defining properties (secondary species criteria). A unified species concept can be achieved by treating existence as a separately evolving metapopulation lineage as the only necessary property of species and the former secondary species criteria as different lines of evidence (operational criteria) relevant to assessing lineage separation. This unified concept of species has several consequences for species delimitation, including the following: First, the issues of species conceptualization and species delimitation are clearly separated; the former secondary species criteria are no longer considered relevant to species conceptualization but only to species delimitation. Second, all of the properties formerly treated as secondary species criteria are relevant to species delimitation to the extent that they provide evidence of lineage separation. Third, the presence of any one of the properties (if appropriately interpreted) is evidence for the existence of a species, though more properties and thus more lines of evidence are associated with a higher degree of corroboration. Fourth, and perhaps most significantly, a unified species concept shifts emphasis away from the traditional species criteria, encouraging biologists to develop new methods of species delimitation that are not tied to those properties.

  10. Invasive Species

    Science.gov (United States)

    Invasive species have significantly changed the Great Lakes ecosystem. An invasive species is a plant or animal that is not native to an ecosystem, and whose introduction is likely to cause economic, human health, or environmental damage.

  11. A new cryptic species of lizard (Sauria: Teiidae: Gymnophthalmus) from Venezuela

    NARCIS (Netherlands)

    Hoogmoed, M.S.; Cole, C.J.; Ayarzaguena, J.

    1992-01-01

    Gymnophthalmus cryptus spec. nov. is described and illustrated on the basis of males and females collected in the Territorio Federal Amazonas, southern Venezuela. Some details on ecology and distribution are also presented. The females of G. cryptus are very similar to the unisexual Gymnophthalmus u

  12. Increased diversification rates follow shifts to bisexuality in liverworts

    DEFF Research Database (Denmark)

    Laenen, Benjamin; Machac, Antonin; Gradstein, S. Robbert

    2016-01-01

    Shifts in sexual systems are one of the key drivers of species diversification. In contrast to angiosperms, unisexuality prevails in bryophytes. Here, we test the hypotheses that bisexuality evolved from an ancestral unisexual condition and is a key innovation in liverworts. We investigate whether...

  13. Invasive species

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This is a summary of management activities and research related to invasive species on Neal Smith National Wildlife Refuge between 1992 and 2009. As part of the...

  14. Species accounts. Chapter 4

    Science.gov (United States)

    Margaret K. Trani; W. Mark Ford; Brian R., eds. Chapman

    2007-01-01

    Narrative accounts for each species are presented by several authors in a consistent format to convey specific information relative to that mammal. The orders are arranged phylogenetically; families and species are arranged alphabetically to facilitate finding a particular species.

  15. Timing and duration of hatching in gynogenetic, triploid, tetraploid, and hybrid progenies in rainbow trout

    OpenAIRE

    Chevassus B; Quillet Edwige; Devaux A.

    1988-01-01

    La vitesse moyenne de développement embryonnaire (mesurée par la date d’éclosion) et sa variabilité ont été étudiées dans sept types de descendances chez la truite arc-en-ciel : des témoins diploïdes, des gynogénétiques diploïdes, des triploïdes obtenus par rétention du second globule polaire (choc thermique chaud) et des triploïdes obtenus par croisement direct entre une femelle diploïde et un mâle tétraploïde, des tétraploïdes et des hybrides diploïdes ou triploïdes entre la femelle tr...

  16. Sperm density required for inducing gynogenetic haploidy in scallop Chlamys nobilis

    Digital Repository Service at National Institute of Oceanography (India)

    Goswami, U.

    Experiments conducted for standardizing sperm density for artificial insemination and inducing gynogenesis by ultra-violet rays irradiated sperms in Chlamys nobilis showed that 10:1 ratio of sperms to eggs, gave maximum rate of fertilization...

  17. Gynogenetic induction in marine bivalve molluscs for improvement of stocks: Standardization of some important factors

    Digital Repository Service at National Institute of Oceanography (India)

    Goswami, U.

    Experiments conducted for standardizing sperm density for artificial insemination of Chlamys mobilis prior to inducing gynogenesis by ultra-violet rays irradiated sperms showed that 10:1 ratio of sperms to eggs should be maintained for getting...

  18. Induction of gynogenetic haploidy in oyster Crassostrea gigas, using ultra violet irradiated sperms

    Digital Repository Service at National Institute of Oceanography (India)

    Goswami, U.

    Eggs of Crassostrea gigas were fertilized with sperms exposed to different doses of UV irradiations by keeping a constant rate of 121.47 ergs. mm/2 sec/1 and changing the period of exposure from 4 to 90 sec. Samples of larvae were analysed...

  19. Agroforestry Species Switchboard

    DEFF Research Database (Denmark)

    Kindt, R.; John, I.; Ordonez, J.;

    2016-01-01

    The current version of the Agroforestry Species Switchboard documents the presence of a total of 26,135 plant species (33,813 species including synonyms) across 19 web-based databases. When available, hyperlinks to information on the selected species in particular databases are provided. In total...

  20. Agroforestry Species Switchboard

    DEFF Research Database (Denmark)

    Kindt, R.; John, I.; Ordonez, J.

    2016-01-01

    The current version of the Agroforestry Species Switchboard documents the presence of a total of 26,135 plant species (33,813 species including synonyms) across 19 web-based databases. When available, hyperlinks to information on the selected species in particular databases are provided. In total...

  1. Endangered Species Act

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The purpose of the Endangered Species Act (ESA) is to protect and recover imperiled species and the ecosystems upon which they depend. The U.S. Fish and Wildlife...

  2. Invasive forest species

    Science.gov (United States)

    Barbara L. Illman

    2006-01-01

    Nonnative organisms that cause a major change to native ecosystems-once called foreign species, biological invasions, alien invasives, exotics, or biohazards–are now generally referred to as invasive species or invasives. invasive species of insects, fungi, plants, fish, and other organisms present a rising threat to natural forest ecosystems worldwide. Invasive...

  3. Species choice, provenance and species trials among native Brazilian species

    Energy Technology Data Exchange (ETDEWEB)

    Drumond, M.A.

    1982-01-01

    Six papers from the conference are presented. Drumond, M.A., Potential of species native to the semi-arid tropics, 766-781, (Refs. 18), reports on Anadenanthera macrocarpa, Mimosa species, Schinopsis brasiliensis, Spondias tuberosa, Ziziphus joazeiro, Cnidoscolus phyllacanthus, Bursera leptophleos (leptophloeos), Tabebuia impetiginosa, Astronium urundeuva, and Mimosa caesalpinia. Monteiro, R.F.R., Speltz, R.M., Gurgel, J.T. do A.; Silvicultural performance of 24 provenances of Araucaria angustifolia in Parana, 814-824, (Refs. 8). Pires, C.L. da S., Kalil Filho, A.N., Rosa, P.R.F. da, Parente, P.R., Zanatto, A.C.S.; Provenance trials of Cordia alliodora in the State of Sao Paulo, 988-995, (Refs. 9). Nogueira, J.C.B., Siqueira, A.C.M.F., Garrido, M.A.O., Gurgel Garrido, L.M. do A., Rosa, P.R.F., Moraes, J.L. de, Zandarin, M.A., Gurgel Filho, O.A., Trials of some native species in various regions of the State of Sao Paulo, 1051-1063, (Refs. 9) describes Centrolobium tomentosum, Peltophorum dubium, Tabebuia vellosoi, Cariniana legalis, and Balfourodendron riedelianum. Batista, M.P., Borges, J.F., Franco, M.A.B.; Early growth of a native species in comparison with exotics in northeastern Para, Brazil, 1105-1110, (Refs. 3). Jacaranda copaia is compared with Gmelina arborea, Pinus caribaea various hondurensis, Eucalyptus deglupta, and E. urophylla. Lima, P.C.F., Souza, S.M. de, Drumond, M.A.; Trials of native forest species at Petrolina, Pernambuco, 1139-1148, (Refs. 8), deals with Anadenanthera macrocarpa, Piptadenia obliqua, Pithecellobium foliolosum, Astronium urundeuva, Schinopsis brasiliensis, Cassia excelsa, Caesalpinia pyramidalis, Parkia platycephala, Pseudobombax simplicifolium, Tabebuia impetiginosa, Caesalpinia ferrea, and Aspidosperma pyrifolium. 18 references.

  4. Support your local species

    DEFF Research Database (Denmark)

    Stärk, Johanna

    Nearly a quarter of all animal species within the European Union are threatened with extinction. Protecting many of these species will require the full spectrum of conservation actions from in-situ to ex-situ management. Holding an estimated 44% of EU Red Listed terrestrial vertebrates, zoos hereby...

  5. The Origin of Species

    NARCIS (Netherlands)

    Darwin, Charles

    2005-01-01

    In The Origin of Species Darwin outlined his theory of evolution, which proposed that species had been evolving and differentiating over time under the influence of natural selection. On its publication it became hugely influential, bringing about a seismic shift in the scientific view of humanitys

  6. The Origin of Species

    NARCIS (Netherlands)

    Darwin, Charles

    2005-01-01

    In The Origin of Species Darwin outlined his theory of evolution, which proposed that species had been evolving and differentiating over time under the influence of natural selection. On its publication it became hugely influential, bringing about a seismic shift in the scientific view of humanitys

  7. Biofilms of Clostridium species.

    Science.gov (United States)

    Pantaléon, Véronique; Bouttier, Sylvie; Soavelomandroso, Anna Philibertine; Janoir, Claire; Candela, Thomas

    2014-12-01

    The biofilm is a microbial community embedded in a synthesized matrix and is the main bacterial way of life. A biofilm adheres on surfaces or is found on interfaces. It protects bacteria from the environment, toxic molecules and may have a role in virulence. Clostridium species are spread throughout both environments and hosts, but their biofilms have not been extensively described in comparison with other bacterial species. In this review we describe all biofilms formed by Clostridium species during both industrial processes and in mammals where biofilms may be formed either during infections or associated to microbiota in the gut. We have specifically focussed on Clostridium difficile and Clostridium perfringens biofilms, which have been studied in vitro. Regulatory processes including sporulation and germination highlight how these Clostridium species live in biofilms. Furthermore, biofilms may have a role in the survival and spreading of Clostridium species. Copyright © 2014 Elsevier Ltd. All rights reserved.

  8. Extragastric Helicobacter species

    DEFF Research Database (Denmark)

    On, Stephen L.W.; Hynes, S.; Wadstrom, T.

    2002-01-01

    The genus Helicobacter has expanded at a rapid pace and no fewer than 31 species have been named since the proposal of the genus in 1989. Of these 31 species, 22 are principally associated with extragastric niches and there is increasing interest in the role of these taxa in diseases of humans...... and animals. Substantial evidence attests to certain species playing a role in the pathogenesis of enteric, hepatic and biliary disorders and some taxa demonstrate zoonotic potential. The importance of extragastric Helicobacters is likely to be an important topic for research in the near future. Here...

  9. Threatened & Endangered Species Occurrences

    Data.gov (United States)

    Kansas Data Access and Support Center — The database consists of a single statewide coverage of location records for 54 species contained in the Kansas Natural Heritage Inventory database of the Kansas...

  10. DENTURE WEARER: ALCALIGENES SPECIES

    African Journals Online (AJOL)

    associated with Alcaligenes species infection in a patient using an upper single ... patient was HIV negative and VDRL screening for syphilis was also negative. ... status of denture and the underlying oral mucosal, to prevent opportunistic.

  11. Arctic species resilience

    DEFF Research Database (Denmark)

    Mortensen, Lars O.; Forchhammer, Mads C.; Jeppesen, Erik

    and precipitation. Concurrently, phenological change has been recorded in a wide range of plants and animals, with climate change seemingly being the primary driver of these changes. A major concern is whether species and biological systems embrace the plasticity in their phenological responses needed for tracking...... the predicted increase in climate variability. Whereas species may show relatively high phenological resilience to climate change per se, the resilience of systems may be more constrained by the inherent dependence through consumer-resource interactions across trophic levels. During the last 15 years...... Zackenberg Basic, a newly initiated project is focusing on how the changes and variability in the physical environment affects the species phenology and composition, population dynamics and how species specific responses at different trophic levels are carried on to the inter-trophic dynamics of consumers...

  12. Fire Management Species Profiles

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The objective of the Fire Management Species Profile project is to identify habitat management objectives that are specific, measurable, achievable, clearly...

  13. Sub specie aeternitatis

    Directory of Open Access Journals (Sweden)

    Laura Gioeni

    2012-10-01

    Full Text Available Per delineare il rapporto tra etica ed estetica nell'architettura e rispondere alla domanda principale «che cosa è o dovrebbe essere un buon architetto?», il saggio discute la tesi di Wittgenstein secondo cui «l'opera d'arte è l'oggetto visto sub specie aeternitatis e la vita buona è il mondo visto sub specie aeternitatis. Questa è la connessione tra arte ed etica».

  14. Concepts of keystone species and species importance in ecology

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    This paper discussed the keystone species concept and introduced the typical characteristics of keystone species and their identification in communities or ecosystems. Based on the research of the keystone species, the concept of species importance (SI) was first advanced in this paper. The species importance can be simply understood as the important value of species in the ecosystem, which consists of three indexes: species structural important value (SIV), functional important value (FIV) and dynamical important value (DIV). With the indexes, the evaluation was also made on species importance of arbor trees in the Three-Hardwood forests (Fraxinus mandshurica, Juglans mandshurica, and Phellodendron amurense) ecosystem.

  15. Bounding species distribution models

    Directory of Open Access Journals (Sweden)

    Thomas J. STOHLGREN, Catherine S. JARNEVICH, Wayne E. ESAIAS,Jeffrey T. MORISETTE

    2011-10-01

    Full Text Available Species distribution models are increasing in popularity for mapping suitable habitat for species of management concern. Many investigators now recognize that extrapolations of these models with geographic information systems (GIS might be sensitive to the environmental bounds of the data used in their development, yet there is no recommended best practice for “clamping” model extrapolations. We relied on two commonly used modeling approaches: classification and regression tree (CART and maximum entropy (Maxent models, and we tested a simple alteration of the model extrapolations, bounding extrapolations to the maximum and minimum values of primary environmental predictors, to provide a more realistic map of suitable habitat of hybridized Africanized honey bees in the southwestern United States. Findings suggest that multiple models of bounding, and the most conservative bounding of species distribution models, like those presented here, should probably replace the unbounded or loosely bounded techniques currently used [Current Zoology 57 (5: 642–647, 2011].

  16. Management of invasive species

    DEFF Research Database (Denmark)

    Schou, Jesper Sølver; Jensen, Frank

    In this paper, we conduct a number of cost-benefit analyses to clarify whether the establishment of invasive species should be prevented or the damage of such species should be mitigated after introduction. We use the potential establishment of ragweed in Denmark as an empirical case. The main...... impact of the establishment of this invasive species is a substantial increase in the number of allergy cases, which we use as a measure of the physical damage. As valuation methods, we use both the cost-of-illness method and the benefit transfer method to quantify the total gross benefits of the two...... policy actions. Based on the idea of an invasion function, we identify the total and average net benefit under both prevention and mitigation. For both policy actions, the total and average net benefits are significantly positive irrespective of the valuation method used; therefore, both prevention...

  17. Bounding Species Distribution Models

    Science.gov (United States)

    Stohlgren, Thomas J.; Jarnevich, Cahterine S.; Morisette, Jeffrey T.; Esaias, Wayne E.

    2011-01-01

    Species distribution models are increasing in popularity for mapping suitable habitat for species of management concern. Many investigators now recognize that extrapolations of these models with geographic information systems (GIS) might be sensitive to the environmental bounds of the data used in their development, yet there is no recommended best practice for "clamping" model extrapolations. We relied on two commonly used modeling approaches: classification and regression tree (CART) and maximum entropy (Maxent) models, and we tested a simple alteration of the model extrapolations, bounding extrapolations to the maximum and minimum values of primary environmental predictors, to provide a more realistic map of suitable habitat of hybridized Africanized honey bees in the southwestern United States. Findings suggest that multiple models of bounding, and the most conservative bounding of species distribution models, like those presented here, should probably replace the unbounded or loosely bounded techniques currently used [Current Zoology 57 (5): 642-647, 2011].

  18. A new species of Curvularia

    NARCIS (Netherlands)

    Aa, van der H.A.

    1967-01-01

    Curvularia papendorfii, isolated from South African soil, is described as a new species. This species is characterized by greater overall dimensions than in any of the known species, and a hilum to the spore that is not protuberant at all.

  19. Prices and species diversity

    DEFF Research Database (Denmark)

    Sauer, Johannes

    of biodiversity and the appropriate incorporation in stochastic fron-tier models to achieve more realistic measures of production efficiency. We use the empirical example of tobacco production drawing from as well as affecting species diversity in the surrounding forests. We apply a shadow profit distance....... Based on a biologically defined species diver-sity index we incorporate biodiversity either as a desirable output or biodiversity loss as a detrimental input. Beside quantitative shadow price measures the main contribu-tion of the work is the evidence that parametric scores of environmental efficiency...

  20. Prices and species diversity

    DEFF Research Database (Denmark)

    Sauer, Johannes

    . Based on a biologically defined species diver-sity index we incorporate biodiversity either as a desirable output or biodiversity loss as a detrimental input. Beside quantitative shadow price measures the main contribu-tion of the work is the evidence that parametric scores of environmental efficiency...... of biodiversity and the appropriate incorporation in stochastic fron-tier models to achieve more realistic measures of production efficiency. We use the empirical example of tobacco production drawing from as well as affecting species diversity in the surrounding forests. We apply a shadow profit distance...

  1. Bioterrorism and invasive species.

    Science.gov (United States)

    Chomel, B B; Sun, B

    2010-08-01

    The risk of dispersing invasive species, especially human pathogens, through acts of bioterrorism, cannot be neglected. However, that risk appears quite low in comparison with the risk of dispersing animal pathogens that could dramatically burden the agricultural economy of food animal producing countries, such as Australia and countries in Europe and North and South America. Although it is not directly related to bioterrorism, the intentional release of non-native species, particularly undesired companion animals or wildlife, may also have a major economic impact on the environment and, possibly, on animal and human health, in the case of accidental release of zoonotic agents.

  2. Identification and Characterization of VNI/VNII and Novel VNII/VNIV Hybrids and Impact of Hybridization on Virulence and Antifungal Susceptibility Within the C. neoformans/C. gattii Species Complex

    Science.gov (United States)

    Aminnejad, Mojgan; Cogliati, Massimo; Duan, Shuyao; Arabatzis, Michael; Tintelnot, Kathrin; Castañeda, Elizabeth; Lazéra, Marcia; Velegraki, Aristea; Ellis, David; Sorrell, Tania C.; Meyer, Wieland

    2016-01-01

    Cryptococcus neoformans and C. gattii are pathogenic basidiomycetous yeasts and the commonest cause of fungal infection of the central nervous system. Cryptococci are typically haploid but several inter-species, inter-varietal and intra-varietal hybrids have been reported. It has a bipolar mating system with sexual reproduction occurring normally between two individuals with opposite mating types, α and a. This study set out to characterize hybrid isolates within the C. neoformans/C. gattii species complex: seven unisexual mating intra-varietal VNI/VNII (αAAα) and six novel inter-varietal VNII/VNIV (aADα). The URA5-RFLP pattern for VNII/VNIV (aADα) differs from the VNIII (αADa) hybrids. Analysis of the allelic patterns of selected genes for AD hybrids showed 79% or more heterozygosis for the studied loci except for CBS132 (VNIII), which showed 50% of heterozygosity. MALDI-TOF MS was applied to hybrids belonging to different sero/mating type allelic patterns. All hybrid isolates were identified as belonging to the same hybrid group with identification scores ranging between 2.101 to 2.634. All hybrids were virulent when tested in the Galleria mellonella (wax moth) model, except for VNII/VNIV (aADα) hybrids. VNI/VGII hybrids were the most virulent hybrids. Hybrids recovered from larvae manifested a significant increase in capsule and total cell size and produced a low proportion (5–10%) of giant cells compared with the haploid control strains. All strains expressed the major virulence factors—capsule, melanin and phospholipase B—and grew well at 37°C. The minimal inhibitory concentration of nine drugs was measured by micro-broth dilution and compared with published data on haploid strains. MICs were similar amongst hybrids and haploid parental strains. This is the first study reporting natural same sex αAAα intra-varietal VNI/VNII hybrids and aADα inter-varietal VNII/VNIV hybrids. PMID:27764108

  3. A New Species of Weltrichia Braun in North China with a Special Bennettitalean Male Reproductive Organ%本内苏铁类雄性生殖器官Weltrichia属一新种

    Institute of Scientific and Technical Information of China (English)

    李楠; 李勇; 王丽霞; 郑少林; 张武

    2004-01-01

    报道了本内苏铁类雄性生殖器官Weltrichia属的一个新种--Weltrichia daohugouensis sp.nov.,标本发现于内蒙古宁城山头乡道虎沟村附近的中侏罗统海房沟组.它是一个分离保存的本内苏铁类单性雄球花(球穗花序),在侧向压缩的平面上展开,呈扇形.基部球花梗未保存,下部由11个窄楔形的裂片融合成漏斗状或杯状,上部裂开成数目相等的游离的小孢子叶.每个小孢子叶的上部有两列花粉囊.文中对新种进行了详细地描述和讨论.并对W.huangbanjigouensis Su et Zheng的鉴定特征进行了修订.%We report a new species of the genus Weltrichia Braun with a special Bennettitalean male reproductive organ-W. daohugouensis Li et Zheng sp. nov., which was discovered from Haifanggou Formation (Middle Jurassic) in Daohugou Village, Shantou Town, Ningcheng County, Inner Mongolia (Nei Mongol)Autonomous Region, China. It is a unisexual male strobile which was a laterally compressed preserved specimen being fan-shaped and appearing as half of a whole. Its base and peduncle are lost while the lower part of the strobile consists of eleven narrowly wedged segments fused together into a funnel or cup-like.In the upper part of the strobile these segments separate into free structure (microsporophylls), each bearing two rows of pollen sacs (synangia). In this paper a new species W. daohugouensis Li et Zheng sp.nov. is described and the identification of the W. huangbanjigouensis Sun et Zheng is emended.

  4. Coevolution of Symbiotic Species

    CERN Document Server

    Leok, B T M

    1996-01-01

    This paper will consider the coevolution of species which are symbiotic in their interaction. In particular, we shall analyse the interaction of squirrels and oak trees, and develop a mathematical framework for determining the coevolutionary equilibrium for consumption and production patterns.

  5. Positive feedback in species communities

    NARCIS (Netherlands)

    Gerla, D.J.

    2012-01-01

    Sometimes the eventual population densities in a species community depend on the initial densities or the arrival times of species. If arrival times determine species composition, a priority effect has occurred. Priority effects may occur if the species community exhibits alternative stable states (

  6. The functional biogeography of species

    DEFF Research Database (Denmark)

    Carstensen, D.W.; Dalsgaard, B.; Svenning, J.-C.

    2013-01-01

    between species traits and large-scale species distribution patterns in archipelagos, we use a network approach to classify birds as one of four biogeographical species roles: peripherals, connectors, module hubs, and network hubs. These roles are based upon the position of species within the modular...

  7. Identification of Malassezia species.

    Science.gov (United States)

    Kindo, A J; Sophia, S K C; Kalyani, J; Anandan, S

    2004-01-01

    Malassezia spp. are lipophilic unipolar yeasts recognized as commensals of skin that may be pathogenic under certain conditions. The genus Malassezia now comprises of seven species. This study was aimed at using a simple practical approach to speciate Malassezia yeasts from clinical material. Seventy skin scrapings from patients with pityriasis versicolor infection, positive in 10% potassium hydroxide (KOH), were cultured onto modified Dixon's agar (mDixon's agar) and Sabouraud dextrose agar (SDA) and incubated at 32 degrees C. Speciation was done on the basis of Gram stain morphology, catalase test, and utilization of Tweens. Out of 70 scrapings 48 (68.75%) showed growth on mDixon's agar. The commonest isolate was M. sympodialis (28, 58%) followed by M. globosa (19, 40%) and one isolate was (2%) of M. restricta. M. sympodialis was the commonest species affecting our population and there was no isolation of M. obtusa, M. slooffiae, M. pachydermatis and M. furfur.

  8. Arctic species resilience

    DEFF Research Database (Denmark)

    Mortensen, Lars O.; Forchhammer, Mads C.; Jeppesen, Erik

    and precipitation. Concurrently, phenological change has been recorded in a wide range of plants and animals, with climate change seemingly being the primary driver of these changes. A major concern is whether species and biological systems embrace the plasticity in their phenological responses needed for tracking......The peak of biological activities in Arctic ecosystems is characterized by a relative short and intense period between the start of snowmelt until the onset of frost. Recent climate changes have induced larger seasonal variation in both timing of snowmelt as well as changes mean temperatures...... the predicted increase in climate variability. Whereas species may show relatively high phenological resilience to climate change per se, the resilience of systems may be more constrained by the inherent dependence through consumer-resource interactions across trophic levels. During the last 15 years...

  9. Trichoderma species from China

    Institute of Scientific and Technical Information of China (English)

    ZHANG Chu-long; XU Tong

    2004-01-01

    @@ Seventeen species of Trichoderma, isolated from soil or tree bark from China are identified based on morphological and physiological characters, and from their phylogenetic position inferred from parsimony analyses of nucleotide sequences of the internal transcribed spacer regions of the rDNA cluster (ITS1 and 2) and partial sequences of translation elongation factor 1-alpha (tef1) . There were T. citrinoviride, T. longibrachiatum, T. sinensis in section Longibrachiatum, T. atroviride, T.koningii, T. viride, T. asperellum, T. hamatum, T. erinaceum in section Trichoderma, T.harzianum (H.lixii) , T. inhamatum, T. velutinum , T. cerinum , T. strictipile , T. spirale ,T. virens, H. nigrovirens (Trichoderma sp.) in section Pachybasium. Among them four species:T. asperellum , T. velutinum , T. cerinum , T. spirale were reported firstly in China. In addition, two suspected new taxa (Trichoderma spp.) in Trichoderma section were proposed:Trichoderma sp. 1 (ZAUT261, 4, 4A, 15A, 2C), Trichoderma sp. 2 (2B, 5, 7A, 7B, 9A).Trichoderma sp. 1 was similar to T. hamatum , but the temperature optimum for mycelial growth was lower than that of T. hamatum and the species tended to form hemisphaerical pustule with Telatively larger conidia (average length 4.6 μm × 2.8 μm). Trichoderma sp. 2 was distinguished morphologically from related species T. strigosum, T. pubescens, T. erinaceum, T. hamatum and Trichoderma sp. 1 in pustules on CMD without fertile or sterile conidiophore elongation and distinctive phialide shape, the conidiophore branches similar to T. koningii, but the conidia similar to T. viride, subglobose, conspicuously tuberculate.

  10. Introduced Terrestrial Species Richness

    Science.gov (United States)

    These data represent predicted current distributions of all introduced mammals, birds, reptiles, amphibians and butterflies in the Middle-Atlantic region. These data are available for both 8-digit HUCs and EMAP hexagons. The data are species counts for each spatial unit. More information about these resources, including the variables used in this study, may be found here: https://edg.epa.gov/data/Public/ORD/NERL/ReVA/ReVA_Data.zip.

  11. Bounding species distribution models

    Institute of Scientific and Technical Information of China (English)

    Thomas J. STOHLGREN; Catherine S. JARNEVICH; Wayne E. ESAIAS; Jeffrey T. MORISETTE

    2011-01-01

    Species distribution models are increasing in popularity for mapping suitable habitat for species of management concern.Many investigators now recognize that extrapolations of these models with geographic information systems (GIS) might be sensitive to the environmental bounds of the data used in their development,yet there is no recommended best practice for “clamping” model extrapolations.We relied on two commonly used modeling approaches:classification and regression tree (CART) and maximum entropy (Maxent) models,and we tested a simple alteration of the model extrapolations,bounding extrapolations to the maximum and minimum values of primary environmental predictors,to provide a more realistic map of suitable habitat of hybridized Africanized honey bees in the southwestern United States.Findings suggest that multiple models of bounding,and the most conservative bounding of species distribution models,like those presented here,should probably replace the unbounded or loosely bounded techniques currently used [Current Zoology 57 (5):642-647,2011].

  12. Genomics of Bacillus Species

    Science.gov (United States)

    Økstad, Ole Andreas; Kolstø, Anne-Brit

    Members of the genus Bacillus are rod-shaped spore-forming bacteria belonging to the Firmicutes, the low G+C gram-positive bacteria. The Bacillus genus was first described and classified by Ferdinand Cohn in Cohn (1872), and Bacillus subtilis was defined as the type species (Soule, 1932). Several Bacilli may be linked to opportunistic infections. However, pathogenicity among Bacillus spp. is mainly a feature of bacteria belonging to the Bacillus cereus group, including B. cereus, Bacillus anthracis, and Bacillus thuringiensis. Here we review the genomics of B. cereus group bacteria in relation to their roles as etiological agents of two food poisoning syndromes (emetic and diarrhoeal).

  13. Identification of malassezia species

    Directory of Open Access Journals (Sweden)

    Kindo A

    2004-01-01

    Full Text Available Malassezia spp. are lipophilic unipolar yeasts recognized as commensals of skin that may be pathogenic under certain conditions. The genus Malassezia now comprises of seven species. This study was aimed at using a simple practical approach to speciate Malassezia yeasts from clinical material. Seventy skin scrapings from patients with pityriasis versicolor infection, positive in 10% potassium hydroxide (KOH, were cultured onto modified Dixon′s agar (mDixon′s agar and Sabouraud dextrose agar (SDA and incubated at 32ºC. Speciation was done on the basis of Gram stain morphology, catalase test, and utilization of Tweens. Out of 70 scrapings 48 (68.75% showed growth on mDixon′s agar. The commonest isolate was M. sympodialis (28, 58% followed by M. globosa (19, 40% and one isolate was (2% of M. restricta. M. sympodialis was the commonest species affecting our population and there was no isolation of M. obtusa, M. slooffiae, M. pachydermatis and M. furfur.

  14. Save Our Species: Protecting Endangered Species from Pesticides.

    Science.gov (United States)

    Environmental Protection Agency, Washington, DC.

    This full-size poster profiles 11 wildlife species that are endangered. Color illustrations of animals and plants are accompanied by narrative describing their habitats and reasons for endangerment. The reverse side of the poster contains information on the Endangered Species Act, why protecting endangered and threatened species is important, how…

  15. A novel nucleo-cytoplasmic hybrid clone formed via androgenesis in polyploid gibel carp

    Directory of Open Access Journals (Sweden)

    Zhou Li

    2011-03-01

    -cytoplasmic hybrid female still maintains its gynogenetic ability. Based on the present and previous findings, we discuss the association of rapid genetic changes and high genetic diversity with various ploidy levels and multiple reproduction modes in several unisexual and sexual complexes of vertebrates and even other invertebrates.

  16. Endangered Species Act Critical Habitat

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Critical habitat (CH) is designated for the survival and recovery of species listed as threatened or endangered under the Endangered Species Act (ESA). Critical...

  17. New species of Malaysian ferns

    NARCIS (Netherlands)

    Holttum, R.E.

    1962-01-01

    The present paper includes descriptions of several new species of ferns found among recent collections from various parts of Malaysia; also two new combinations of names of species which are of interest on account of their taxonomic history.

  18. The functional biogeography of species

    DEFF Research Database (Denmark)

    Carstensen, D.W.; Dalsgaard, B.; Svenning, J.-C.

    2013-01-01

    Biogeographical systems can be analyzed as networks of species and geographical units. Within such a biogeographical network, individual species may differ fundamentally in their linkage pattern, and therefore hold different topological roles. To advance our understanding of the relationship betw...

  19. Timeless standards for species delimitation.

    Science.gov (United States)

    Amorim, Dalton S; Santos, Charles Morphy D; Krell, Frank-Thorsten; Dubois, Alain; Nihei, Silvio S; Oliveira, Otto M P; Pont, Adrian; Song, Hojun; Verdade, Vanessa K; Fachin, Diego A; Klassa, Bruna; Lamas, Carlos José E; Oliveira, Sarah S; Carvalho, Claudio J B De; Mello-Patiu, Cátia A; Hajdu, Eduardo; Couri, Márcia S; Silva, Vera C; Capellari, Renato S; Falaschi, Rafaela L; Feitosa, Rodrigo M; Prendini, Lorenzo; Pombal, José P Jr; Fernández, Fernando; Rocha, Rosana M; Lattke, John E; Caramaschi, Ulisses; Duarte, Marcelo; Marques, Antonio Carlos; Reis, Roberto E; Kurina, Olavi; Takiya, Daniela M; Tavares, Marcos; Fernandes, Daniel Silva; Franco, Francisco Luís; Cuezzo, Fabiana; Paulson, Dennis; Guénard, Benoit; Schlick-Steiner, Birgit C; Arthofer, Wolfgang; Steiner, Florian M; Fisher, Brian L; Johnson, Robert A; Delsinne, Thibaut Dominique; Donoso, David A; Mulieri, Pablo Ricardo; Patitucci, Luciano Damián; Carpenter, James M; Herman, Lee; Grimaldi, David

    2016-07-08

    Recently a new species of bombyliid fly, Marleyimyia xylocopae, was described by Marshall & Evenhuis (2015) based on two photographs taken during fieldwork in the Republic of South Africa. This species has no preserved holotype. The paper generated some buzz, especially among dipterists, because in most cases photographs taken in the field provide insufficient information for properly diagnosing and documenting species of Diptera.

  20. Biosystematic studies on the Muellerianella complex (Delphacidae), Homoptera, auchenorrhyncha

    NARCIS (Netherlands)

    Drosopoulos, S.

    1977-01-01

    The genus Muellerianella comprises the species: M. farmairei, M. brevipennis, M. relicta and one pseudogamous all-female biotype M. fairmairei (3n). The bisexual species M. fairmairei and M. brevipennis as well as the unisexual M. fairmairei (3n) were investigated from a biosystematic point of view.

  1. Electrosmog and species conservation

    Energy Technology Data Exchange (ETDEWEB)

    Balmori, Alfonso, E-mail: abalmorimartinez@gmail.com

    2014-10-15

    Despite the widespread use of wireless telephone networks around the world, authorities and researchers have paid little attention to the potential harmful effects of mobile phone radiation on wildlife. This paper briefly reviews the available scientific information on this topic and recommends further studies and specific lines of research to confirm or refute the experimental results to date. Controls must be introduced and technology rendered safe for the environment, particularly, threatened species. - Highlights: • Studies have shown effects in both animals and plants. • Two thirds of the studies reported ecological effects. • There is little research in this area and further research is needed. • The technology must be safe. • Controls should be introduced to mitigate the possible effects.

  2. Insular species swarm goes underground

    DEFF Research Database (Denmark)

    P. S. Reboleira, Ana Sofia; Enghoff, Henrik

    2014-01-01

    Two new species of the genus Cylindroiulus Verhoeff, 1894, C. julesvernei and C. oromii, are described from the subterranean ecosystem of Madeira Island, Portugal. Species are illustrated with photographs and diagrammatic drawings. The new species belong to the Cylindroiulus madeirae......-group, an insular species swarm distributed in the archipelagos of Madeira and the Canary Islands. We discuss the differences between the new species and their relatives and present information on the subterranean environment of Madeira. An updated overview of the subterranean biodiversity of millipedes...

  3. Hebeloma species associated with Cistus.

    Science.gov (United States)

    Eberhardt, Ursula; Beker, Henry J; Vila, Jordi; Vesterholt, Jan; Llimona, Xavier; Gadjieva, Rena

    2009-01-01

    The genus Hebeloma has a number of species highly specific to Cistus and others that occur with several host genera. This paper discusses the species of Hebeloma that appear to be ectomycorrhizal with Cistus, judging from their occurrence when Cistus is the only available host. The previously unknown species H. plesiocistum spec. nov. is described. We also provide a key to the known Hebeloma associates of Cistus. Molecular analyses based on ITS sequence data further illustrate the distinctness of the newly described species and difficulties in the species delimitation with view to H. erumpens. Specific associations with Cistus may have evolved more than once within the genus Hebeloma.

  4. Species of Wadicosa (Araneae, Lycosidae): a new species from Madagascar.

    Science.gov (United States)

    Kronestedt, Torbjörn

    2017-05-10

    Since establishing the wolf spider genus Wadicosa Zyuzin, 1985 (Zyuzin 1985), eleven species have been accepted in it, either by transfer from Lycosa Latreille, 1804 or Pardosa C.L. Koch, 1847 or by original designation (WSC 2017). However, according to Kronestedt (1987), additional species wait to be formally transferred to Wadicosa. The genus is restricted to the Old World, with one species, Wadicosa jocquei Kronestedt, 2015, recently described from Madagascar and surrounding islands.

  5. Native species that can replace exotic species in landscaping

    Directory of Open Access Journals (Sweden)

    Elisabeth Regina Tempel Stumpf

    2015-08-01

    Full Text Available Beyond aesthetics, the contemporary landscaping intends to provide other benefits for humans and environment, especially related to the environmental quality of urban spaces and conservation of the species. A trend in this direction is the reduction in the use of exotic plants in their designs, since, over time, they can become agents of replacement of native flora, as it has occurred in Rio Grande do Sul with many species introduced by settlers. However, the use of exotic species is unjustifiable, because the flora diversity of the Bioma Pampa offers many native species with appropriate features to the ornamental use. The commercial cultivation and the implantation of native species in landscaped areas constitute innovations for plant nurseries and landscapers and can provide a positive reduction in extractivism, contributing to dissemination, exploitation and preservation of native flora, and also decrease the impact of chemical products on environment. So, this work intends to identify native species of Bioma Pampa with features and uses similar to the most used exotic species at Brazilian landscaping. The species were selected from consulting books about native plants of Bioma Pampa and plants used at Brazilian landscaping, considering the similarity on habit and architecture, as well as characteristics of leafs, flowers and/or fruits and environmental conditions of occurrence and cultivation. There were identified 34 native species able to properly replace exotic species commonly used. The results show that many native species of Bioma Pampa have interesting ornamental features to landscape gardening, allowing them to replace exotic species that are traditionally cultivated.

  6. New mite species associated with certain plant species from Guam

    Directory of Open Access Journals (Sweden)

    Gadi V.P. Reddy

    2011-04-01

    Full Text Available Several new mite species have been reported from certain plants from Guam. Most remarkably, the spider mite, Tetranychus marianae (Prostigmata: Tetranychidae and the predatory mite Phytoseius horridus (Mesostigmata: Phytoseiidae (Solanum melongena have been found on eggplant. The noneconomically important species of Brevipalpus californicus(Banks Prostigmata: Tenuipalpidae,Eupodes sp. (Acarina: Eupodidae and predator Cunaxa sp. (Prostigmata: Cunaxidae have been reported on guava (Psidium guajava L.. Also, the non-economically important species Brevipalpus californicus Prostigmata: Tenuipalpidae, Lepidoglyphus destructor (Astigmata: Glycyphagidae and a predator Amblyseius obtusus, species group Amblyseius near lentiginosus (Mesostigmata: Phytoseiidae, have been recorded on cycad (Cycas micronesica.

  7. Ring species as demonstrations of the continuum of species formation

    DEFF Research Database (Denmark)

    Pereira, Ricardo José Do Nascimento; Wake, David B.

    2015-01-01

    In the mid-20th century, Ernst Mayr (1942) and Theodosius Dobzhansky (1958) championed the significance of 'circular overlaps' or 'ring species' as the perfect demonstration of the gradual nature of species formation. As an ancestral species expands its range, wrapping around a geographic barrier...... resulted in restrictive gene flow relative to that observed around the ring, their results suggest that circular overlaps might be more common in nature than currently recognized in the literature. Most importantly, this work shows that the continuum of species formation that Mayr and Dobzhansky praised...

  8. Confronting species distribution model predictions with species functional traits.

    Science.gov (United States)

    Wittmann, Marion E; Barnes, Matthew A; Jerde, Christopher L; Jones, Lisa A; Lodge, David M

    2016-02-01

    Species distribution models are valuable tools in studies of biogeography, ecology, and climate change and have been used to inform conservation and ecosystem management. However, species distribution models typically incorporate only climatic variables and species presence data. Model development or validation rarely considers functional components of species traits or other types of biological data. We implemented a species distribution model (Maxent) to predict global climate habitat suitability for Grass Carp (Ctenopharyngodon idella). We then tested the relationship between the degree of climate habitat suitability predicted by Maxent and the individual growth rates of both wild (N = 17) and stocked (N = 51) Grass Carp populations using correlation analysis. The Grass Carp Maxent model accurately reflected the global occurrence data (AUC = 0.904). Observations of Grass Carp growth rate covered six continents and ranged from 0.19 to 20.1 g day(-1). Species distribution model predictions were correlated (r = 0.5, 95% CI (0.03, 0.79)) with observed growth rates for wild Grass Carp populations but were not correlated (r = -0.26, 95% CI (-0.5, 0.012)) with stocked populations. Further, a review of the literature indicates that the few studies for other species that have previously assessed the relationship between the degree of predicted climate habitat suitability and species functional traits have also discovered significant relationships. Thus, species distribution models may provide inferences beyond just where a species may occur, providing a useful tool to understand the linkage between species distributions and underlying biological mechanisms.

  9. Uncommon Species and Other Features

    Data.gov (United States)

    Vermont Center for Geographic Information — The Vermont Fish and Wildlife Department's Natural Heritage Inventory (NHI) maintains a database of uncommon, rare, threatened and endangered species and natural...

  10. Incorporating Context Dependency of Species Interactions in Species Distribution Models.

    Science.gov (United States)

    Lany, Nina K; Zarnetske, Phoebe L; Gouhier, Tarik C; Menge, Bruce A

    2017-07-01

    Species distribution models typically use correlative approaches that characterize the species-environment relationship using occurrence or abundance data for a single species. However, species distributions are determined by both abiotic conditions and biotic interactions with other species in the community. Therefore, climate change is expected to impact species through direct effects on their physiology and indirect effects propagated through their resources, predators, competitors, or mutualists. Furthermore, the sign and strength of species interactions can change according to abiotic conditions, resulting in context-dependent species interactions that may change across space or with climate change. Here, we incorporated the context dependency of species interactions into a dynamic species distribution model. We developed a multi-species model that uses a time-series of observational survey data to evaluate how abiotic conditions and species interactions affect the dynamics of three rocky intertidal species. The model further distinguishes between the direct effects of abiotic conditions on abundance and the indirect effects propagated through interactions with other species. We apply the model to keystone predation by the sea star Pisaster ochraceus on the mussel Mytilus californianus and the barnacle Balanus glandula in the rocky intertidal zone of the Pacific coast, USA. Our method indicated that biotic interactions between P. ochraceus and B. glandula affected B. glandula dynamics across >1000 km of coastline. Consistent with patterns from keystone predation, the growth rate of B. glandula varied according to the abundance of P. ochraceus in the previous year. The data and the model did not indicate that the strength of keystone predation by P. ochraceus varied with a mean annual upwelling index. Balanus glandula cover increased following years with high phytoplankton abundance measured as mean annual chlorophyll-a. M. californianus exhibited the same

  11. Fuzzy species among recombinogenic bacteria

    Directory of Open Access Journals (Sweden)

    Fraser Christophe

    2005-03-01

    Full Text Available Abstract Background It is a matter of ongoing debate whether a universal species concept is possible for bacteria. Indeed, it is not clear whether closely related isolates of bacteria typically form discrete genotypic clusters that can be assigned as species. The most challenging test of whether species can be clearly delineated is provided by analysis of large populations of closely-related, highly recombinogenic, bacteria that colonise the same body site. We have used concatenated sequences of seven house-keeping loci from 770 strains of 11 named Neisseria species, and phylogenetic trees, to investigate whether genotypic clusters can be resolved among these recombinogenic bacteria and, if so, the extent to which they correspond to named species. Results Alleles at individual loci were widely distributed among the named species but this distorting effect of recombination was largely buffered by using concatenated sequences, which resolved clusters corresponding to the three species most numerous in the sample, N. meningitidis, N. lactamica and N. gonorrhoeae. A few isolates arose from the branch that separated N. meningitidis from N. lactamica leading us to describe these species as 'fuzzy'. Conclusion A multilocus approach using large samples of closely related isolates delineates species even in the highly recombinogenic human Neisseria where individual loci are inadequate for the task. This approach should be applied by taxonomists to large samples of other groups of closely-related bacteria, and especially to those where species delineation has historically been difficult, to determine whether genotypic clusters can be delineated, and to guide the definition of species.

  12. Antifungal compounds from Piper species

    Science.gov (United States)

    Piper is a big genus of the plant family Piperaceae, with more than 700 species widely distributed in the tropical and subtropical regions of the world. Some species are used in folk medicine as analgesics, antiseptics, insecticides, and antimicrobials or for the treatment of toothache, haemorrhoid...

  13. Hebeloma species associated with Cistus

    NARCIS (Netherlands)

    Eberhardt, U.; Beker, H.J.; Vila, J.; Vesterholt, J.; Llimona, X.; Gadjieva, R.

    2009-01-01

    The genus Hebeloma has a number of species highly specific to Cistus and others that occur with several host genera. This paper discusses the species of Hebeloma that appear to be ectomycorrhizal with Cistus, judging from their occurrence when Cistus is the only available host. The previously

  14. The Colletotrichum gigasporum species complex

    NARCIS (Netherlands)

    Liu, F.; Cai, L.; Crous, P.W.; Damm, U.

    2014-01-01

    In a preliminary analysis, 21 Colletotrichum strains with large conidia preserved in the CBS culture collection clustered with a recently described species, C. gigasporum, forming a clade distinct from other currently known Colletotrichum species complexes. Multi-locus phylogenetic analyses (ITS,

  15. A new species of Arius

    NARCIS (Netherlands)

    Popta, C.M.L.

    1900-01-01

    Among some fishes, forwarded by the late Dr. Bleeker to the Leyden Museum, I came across four specimens evidently belonging to the genus Arius, differing however from all known species of that genus. They therefore represent a new species, which I now describe under the name of Arius Bleekeri in hon

  16. Humans as a Hyperkeystone Species.

    Science.gov (United States)

    Worm, Boris; Paine, Robert T

    2016-08-01

    Ecologists have identified numerous keystone species, defined as organisms that have outsized ecological impacts relative to their biomass. Here we identify human beings as a higher-order or 'hyperkeystone' species that drives complex interaction chains by affecting other keystone actors across different habitats. Strong indirect effects and a global reach further characterize these interactions and amplify the impacts of human activities on diverse ecosystems, from oceans to forests. We require better understanding of hyperkeystone interaction chains most urgently, especially for marine species and terrestrial large carnivores, which experience relatively higher exploitation rates than other species. This requires innovative approaches that integrate the study of human behavior with food-web theory, and which might provide surprising new insights into the complex ecology of our own species.

  17. Species delimitation and global biosecurity.

    Science.gov (United States)

    Boykin, Laura M; Armstrong, Karen F; Kubatko, Laura; De Barro, Paul

    2012-01-01

    Species delimitation directly impacts on global biosecurity. It is a critical element in the decisions made by national governments in regard to the flow of trade and to the biosecurity measures imposed to protect countries from the threat of invasive species. Here we outline a novel approach to species delimitation, "tip to root", for two highly invasive insect pests, Bemisia tabaci (sweetpotato whitefly) and Lymantria dispar (Asian gypsy moth). Both species are of concern to biosecurity, but illustrate the extremes of phylogenetic resolution that present the most complex delimitation issues for biosecurity; B. tabaci having extremely high intra-specific genetic variability and L. dispar composed of relatively indistinct subspecies. This study tests a series of analytical options to determine their applicability as tools to provide more rigorous species delimitation measures and consequently more defensible species assignments and identification of unknowns for biosecurity. Data from established DNA barcode datasets (COI), which are becoming increasingly considered for adoption in biosecurity, were used here as an example. The analytical approaches included the commonly used Kimura two-parameter (K2P) inter-species distance plus four more stringent measures of taxon distinctiveness, (1) Rosenberg's reciprocal monophyly, (P(AB)),1 (2) Rodrigo's (P(randomly distinct)),2 (3) genealogical sorting index, (gsi),3 and (4) General mixed Yule-coalescent (GMYC).4,5 For both insect datasets, a comparative analysis of the methods revealed that the K2P distance method does not capture the same level of species distinctiveness revealed by the other three measures; in B. tabaci there are more distinct groups than previously identified using the K2P distances and for L. dipsar far less variation is apparent within the predefined subspecies. A consensus for the results from P(AB), P(randomly distinct) and gsi offers greater statistical confidence as to where genetic limits might

  18. Meiofaunal cryptic species challenge species delimitation: the case of the Monocelis lineata (Platyhelminthes: Proseriata) species complex

    NARCIS (Netherlands)

    Scarpa, F.; Cossu, P.; Lai, T.; Sanna, D.; Curini-Galletti, M.; Casu, M.

    2016-01-01

    Given the pending biodiversity crisis, species delimitation is a critically important task in conservation biology, but its efficacy based on single lines of evidence has been questioned as it may not accurately reflect species limits and relationships. Hence, the use of multiple lines of evidence

  19. Species recognition and cryptic species in the Tuber indicum complex.

    Directory of Open Access Journals (Sweden)

    Juan Chen

    Full Text Available Morphological delimitation of Asian black truffles, including Tuber himalayense, T. indicum, T. sinense, T. pseudohimalayense, T. formosanum and T. pseudoexcavatum, has remained problematic and even phylogenetic analyses have been controversial. In this study, we combined five years of field investigation in China with morphological study and DNA sequences analyses (ITS, LSU and β-tubulin of 131 Tuber specimens to show that T. pseudohimalayense and T. pseudoexcavatum are the same species. T. formosanum is a separate species based on its host plants and geographic distribution, combined with minor morphological difference from T. indicum. T. sinense should be treated as a synonym of T. indicum. Our results demonstrate that the present T. indicum, a single described morphological species, should include at least two separate phylogenetic species. These findings are of high importance for truffle taxonomy and reveal and preserve the richness of truffle diversity.

  20. Dietary niche overlap in sympatric asexual and sexual livebearing fishes Poecilia spp.

    Science.gov (United States)

    Scharnweber, K; Plath, M; Winemiller, K O; Tobler, M

    2011-12-01

    The present study investigated the spatiotemporal patterns in trophic resource use in a system of a gynogenetic poeciliid fish, the Amazon molly Poecilia formosa, and its sexual congeners the sailfin molly Poecilia latipinna and the Atlantic molly Poecilia mexicana using gut contents analysis. No statistically significant differences in trophic resource use were found between sexual and gynogenetic species, but gut contents varied significantly across sites and over time. In addition, variation in trophic morphology (i.e. gut length) was significant across sites but not species, and laboratory experiments indicated that gut length is phenotypically plastic. Overall, trophic differentiation between coexisting asexual and sexual Poecilia appears to be minimal, and it is unlikely that niche differentiation contributes to a stable coexistence of the two reproductive forms.

  1. Molecular characterisation of Brucella species.

    Science.gov (United States)

    Scholz, H C; Vergnaud, G

    2013-04-01

    The genus Brucella (Mayer and Shaw, 1920) currently consists often species with validly published names. Within most species further differentiation into biovars exists. Genetically, all Brucella species are highly related to each other, exhibiting sequence similarity values of 98% to 100% in aligned regions (core genome). The population structure is clonal. Despite this close genetic relatedness, the various species can be clearly distinguished from each other by application of high-resolution molecular typing tools, in addition to assessment of phenotype and host preference. Accurate species delineation can be achieved by conventional multiplex polymerase chain reaction (PCR), single nucleotide polymorphism (SNP) analysis and multilocus sequence typing (MLST) or multilocus sequence analysis (MLSA). The last is also suitable for phylogenetic reconstructions, owing to the highly clonal evolution of the different species. Highly discriminatory multilocus variable number of tandem repeats (VNTR) analysis (MLVA) allows both species delineation and differentiation of individual isolates and thus represents a perfect first-line toolfor molecular epidemiological studies within outbreak investigations. More recently,whole genome sequencing (WGS)and the resulting global genome-wide SNP analysis have become available. These novel approaches should help in further understanding the evolution, host specificity and pathogenicity of the genus Brucella.

  2. Trichoderma species collected from Iran

    Institute of Scientific and Technical Information of China (English)

    Doostmorad Zafari

    2004-01-01

    @@ In order to identify Trichoderma species isolated from Iran, Trichoderma selective media and malt extract agar (MEA) were used to isolate Trichoderma species from the soil samples. All the cultures were purified on 2% water agar by hyphal tip method prior to morphological examination.Morphological observations were carried out on the cultures grown on 2% MEA and oat meal agar at 20℃ under ambient laboratory conditions. Macroscopic features of colony and microscopic features of conidiophore, phialid and conidium including position of phialids on conidiophore and shape and size of phialids and conidia were studied and recorded 3-5 days after inoculation. Out of 36 tested isolates, using morphological features and molecular data obtained from ITS1, ITS2 and 5.8S regions fourteen species were identified as follow: T. atroviride, T. ghanense, T. spirale, T. erinaceum, T. citrinoviride, T. saturnisporum,T. longibrachiatum , T. hamatum , T. harzianum, T. inhamatum , T. tomentosum , T.virens, T. asperellum, T. koningii. Among the species T. harzianum and T. virens isolates were the most frequent species. In addition of the mentioned species two Tichoderma sp. were collected from walnut rhizospher that they are not fit to any described species so far. Although one of them are T. brevicumpactum introduced informally.

  3. Molecular Typing of Nocardia Species

    Directory of Open Access Journals (Sweden)

    Seyyed Saeed Eshraghi

    2012-03-01

    Full Text Available Identification of clinically significant Nocardia species is essential for the definitive diagnosis, predict antimicrobial susceptibility, epidemiological purposes, and for an effective treatment. Conventional identification of Nocardia species in routine medical laboratories which is based on phenotypic (cellular morphology, colonial characteristics, biochemical and enzymatic profiles, and chemotaxonomic characteristics is often laborious, and time-consuming. The procedure requires expertise, and newer species can be difficult to differentiate with accuracy from other related species. Alternative methods of identification, such as high performance liquid chromatography (HPLC and molecular biology techniques allow a better characterization of species. The taxonomy of the genus Nocardia has been dramatically been revised during the last decade and more than 30 valid human clinical significance species of Nocardia have been reported. The use of molecular approaches, including 16S rRNA gene sequencing, restriction fragment length polymorphism (RFLP or PCR restriction endonuclease analysis has been the focus of recent investigations to distinguish the isolates of Nocardia from other actinomycetes genera. The methods have revolutionized the characterization of the Nocardiae by providing rapid, sensitive, and accurate identification procedures. The present review describes the currently known medically important pathogenic species of Nocardia.

  4. Floristic composition of the southern cape forests with an annotated checklist

    CSIR Research Space (South Africa)

    Geldenhuys, CJ

    1993-02-01

    Full Text Available ). The species: family ratios of 3.1 for woody plants and 4.5 for herbaceous plants are very low when compared to other forests in Africa and to the surrounding fynbos shrublands. Bisexuality predominates all growth forms and unisexuality (dioecy and monoecy...

  5. Cluster Analysis of Ranunculus Species

    Directory of Open Access Journals (Sweden)

    SURANTO

    2002-01-01

    Full Text Available The aim of the experiment was to examine whether the morphological characters of eleven species of Ranunculus collected from a number of populations were in agreement with the genetic data (isozyme. The method used in this study was polyacrilamide gel electrophoresis using peroxides, estarase, malate dehydrogenase, and acid phosphatase enzymes. The results showed that cluster analysis based on isozyme data have given a good support to classification of eleven species based on morphological groups. This study concluded that in certain species each morphological variation was profit to be genetically based.

  6. Species concepts in Calonectria (Cylindrocladium)

    NARCIS (Netherlands)

    Lombard, L.; Crous, P.W.; Wingfield, B.D.; Wingfield, M.J.

    2010-01-01

    Species of Calonectria and their Cylindrocladium anamorphs are important plant pathogens worldwide. At present 52 Cylindrocladium spp. and 37 Calonectria spp. are recognised based on sexual compatibility, morphology and phylogenetic inference. The polyphasic approach of integrating Biological, Morph

  7. Evolution of mutualism between species

    Energy Technology Data Exchange (ETDEWEB)

    Post, W.M.; Travis, C.C.; DeAngelis, D.L.

    1980-01-01

    Recent theoretical work on mutualism, the interaction between species populations that is mutually beneficial, is reviewed. Several ecological facts that should be addressed in the construction of dynamic models for mutualism are examined. Basic terminology is clarified. (PSB)

  8. Achromobacter species in cystic fibrosis

    DEFF Research Database (Denmark)

    Hansen, C R; Pressler, T; Ridderberg, W;

    2013-01-01

    Achromobacter species leads to chronic infection in an increasing number of CF patients. We report 2 cases of Achromobacter ruhlandii cross-infection between patients after well-described indirect contact....

  9. Malassezia Species and Pityriasis Versicolor

    National Research Council Canada - National Science Library

    Rodoplu, Gulin

    2016-01-01

    Malassezia species are found in part of the normal human cutaneous commensal flora, however it has been known for many years that the Malassezia yeasts are associated with a number of different human...

  10. Phenotypic Plasticity and Species Coexistence.

    Science.gov (United States)

    Turcotte, Martin M; Levine, Jonathan M

    2016-10-01

    Ecologists are increasingly interested in predicting how intraspecific variation and changing trait values impact species interactions and community composition. For many traits, much of this variation is caused by phenotypic plasticity, and thus the impact of plasticity on species coexistence deserves robust quantification. Partly due to a lack of sound theoretical expectations, empirical studies make contradictory claims regarding plasticity effects on coexistence. Our critical review of this literature, framed in modern coexistence theory, reveals that plasticity affects species interactions in ways that could impact stabilizing niche differences and competitive asymmetries. However, almost no study integrates these measures to quantify the net effect of plasticity on species coexistence. To address this challenge, we outline novel empirical approaches grounded in modern theory.

  11. Phase Two Protected Species Valuation

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Nonmarket valuation research has produced economic value estimates for a variety of threatened, endangered, and rare species around the world. Although over 40 value...

  12. Phase One Protected Species Valuation

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Nonmarket valuation research has produced economic value estimates for a variety of threatened, endangered, and rare species around the world. Although over 40 value...

  13. Some species tolerate ocean acidification

    Science.gov (United States)

    Balcerak, Ernie

    2011-12-01

    Increasing carbon dioxide levels lead to rising ocean acidity, which can harm corals and many other species of ocean life. Acidification causes calcium carbonate, which corals usually need to build skeletons, to dissolve. “Every day, ocean acidification is taking up the weight of 6 million midsize cars' worth of carbon, said Nina Keul, a graduate student at the Alfred Wegener Institute for Polar and Marine Research in Germany during a 7 December press conference at the AGU Fall Meeting. Somewhat surprising, though, is that some species are more tolerant of acidic conditions than scientists had expected. For instance, Keul exposed a species of foraminifera, Ammonia tepida, to seawater with varying acidity and varying carbonate ion concentrations. Previous studies had found that foraminifera growth declined with decreasing carbonate levels, but Keul's foraminifera continued to grow in the acidic conditions. She said that the mechanism that allows this species to tolerate the low carbonate conditions is as yet unknown.

  14. The Candida Pathogenic Species Complex

    Science.gov (United States)

    Turner, Siobhán A.; Butler, Geraldine

    2014-01-01

    Candida species are the most common causes of fungal infection. Approximately 90% of infections are caused by five species: Candida albicans, Candida glabrata, Candida tropicalis, Candida parapsilosis, and Candida krusei. Three (C. albicans, C. tropicalis, and C. parapsilosis) belong to the CTG clade, in which the CTG codon is translated as serine and not leucine. C. albicans remains the most commonly isolated but is decreasing relative to the other species. The increasing incidence of C. glabrata is related to its reduced susceptibility to azole drugs. Genome analysis suggests that virulence in the CTG clade is associated with expansion of gene families, particularly of cell wall genes. Similar independent processes took place in the C. glabrata species group. Gene loss and expansion in an ancestor of C. glabrata may have resulted in preadaptations that enabled pathogenicity. PMID:25183855

  15. Infrared spectra of mineral species

    CERN Document Server

    Chukanov, Nikita V

    2014-01-01

    This book details more than 3,000 IR spectra of more than 2,000 mineral species collected during last 30 years. It features full descriptions and analytical data of each sample for which IR spectrum was obtained.

  16. The atlas of endangered species

    National Research Council Canada - National Science Library

    Mackay, R

    2009-01-01

    Vividly illustrated with full-color maps and detailed graphics, The Atlas of Endangered Species catalogs the inhabitants of a wide variety of ecosystems, including forests, mangroves, and coral reefs...

  17. Charcoal anatomy of forest species

    OpenAIRE

    Graciela Inés Bolzon de Muñiz; Silvana Nisgoski; Felipe Zatt Shardosin; Ramiro Faria França

    2012-01-01

    Vegetal charcoal retains the anatomical structure of the wood and may permit its botanical identification, which depends on species characteristics, the charcoal fragments size and preservation state. Anatomical characterization of ten forest species charcoal was done envisaging the identification and control of illegal charcoal. Differences between gymnosperms and angiosperms are evident in carbonized wood. Vessel diameter was statistically different between wood and charcoal in Vatairea gui...

  18. Echinacea species of medicinal use

    Directory of Open Access Journals (Sweden)

    Leon Sorin MUNTEAN

    1998-08-01

    Full Text Available Echinacea species come from North America. Preparations of Echinacea pallida Nutt. and Echinacea purpurea (L. Moench are used in healing many diseases owing to their immunostimulative, antivirus and bacteria, scarifying and anti-inflammatory properties. Echinacea pallida Nutt. displays tap root, linear spear-shaped leaves. Seedling plantation with both species is performed in May and spacing of 50 cm between rows and 30 cm between plants per row. Harvest takes place in the 2-nd year of flowering.

  19. Collective behaviour across animal species

    Science.gov (United States)

    Delellis, Pietro; Polverino, Giovanni; Ustuner, Gozde; Abaid, Nicole; Macrì, Simone; Bollt, Erik M.; Porfiri, Maurizio

    2014-01-01

    We posit a new geometric perspective to define, detect, and classify inherent patterns of collective behaviour across a variety of animal species. We show that machine learning techniques, and specifically the isometric mapping algorithm, allow the identification and interpretation of different types of collective behaviour in five social animal species. These results offer a first glimpse at the transformative potential of machine learning for ethology, similar to its impact on robotics, where it enabled robots to recognize objects and navigate the environment.

  20. Survey protocol for invasive species

    OpenAIRE

    Menza, Charles

    2009-01-01

    This protocol was developed by the Biogeography Branch of NOAA’s Center for Coastal Monitoring and Assessment to support invasive species research by the Papahānaumokuākea Marine National Monument. The protocol’s objective is to detect Carijoa riisei and Hypnea musciformis in deepwater habitats using visual surveys by technical divers. Note: This protocol is designed to detect the presence or absence of invasive species. A distinct protocol is required to collect information on abundance ...

  1. Detecting brucella species in Ecuador

    OpenAIRE

    Luna Jarrín, Ligia Elizabeth

    2015-01-01

    Brucelosis is an emerging zoonotic disease in many countries around the world. There are some reports of Brucella abortus infections in cattle and humans in Ecuador, nevertheless, other Brucella species have not been identified. This study was designed to identify circulating Brucella species in 300 goat samples and one canine fetus from 8 different provinces of the highland Andes of the country. The results showed isolates from Brucella melitensis, Brucella suis, Brucella abortus y Brucella ...

  2. Species Egalitarianism and the Environment

    Directory of Open Access Journals (Sweden)

    Kristin Tiili

    2014-06-01

    Full Text Available A general anthropocentric view of the human species affects the environment and is a major contributing factor in the environmental crisis we are currently facing. A species egalitarian society would have positive effects on the crisis, and particularly in regards to short term goals of decreasing greenhouse gases in the atmosphere. Additionally it would increase the quality of life and alleviate the suffering of countless beings, nonhuman animals and humans alike.

  3. Collective behaviour across animal species.

    Science.gov (United States)

    DeLellis, Pietro; Polverino, Giovanni; Ustuner, Gozde; Abaid, Nicole; Macrì, Simone; Bollt, Erik M; Porfiri, Maurizio

    2014-01-16

    We posit a new geometric perspective to define, detect, and classify inherent patterns of collective behaviour across a variety of animal species. We show that machine learning techniques, and specifically the isometric mapping algorithm, allow the identification and interpretation of different types of collective behaviour in five social animal species. These results offer a first glimpse at the transformative potential of machine learning for ethology, similar to its impact on robotics, where it enabled robots to recognize objects and navigate the environment.

  4. Thromboelastography in Selected Avian Species.

    Science.gov (United States)

    Strindberg, Sophie; Nielsen, Tenna W; Ribeiro, Ângela M; Wiinberg, Bo; Kristensen, Annemarie T; Bertelsen, Mads F

    2015-12-01

    Currently available assay methods and reagents are not optimized for evaluating avian hemostasis; therefore, assessing avian coagulopathies is challenging. Recently, thromboelastography (TEG), which measures the viscoelastic properties of blood, has been used clinically in mammalian species to diagnose and characterize hemostatic disorders. To evaluate TEG in healthy individuals of 6 avian species, we modified existing mammalian TEG protocols to allow analysis of citrated, avian whole-blood samples collected from scarlet ibis (Eudocimus ruber) (n = 13), American flamingos ( Phoenicopterus ruber ) (n = 13), helmeted Guinea fowl ( Numida meleagris ) (n = 12), Amazon parrots (Amazona species) (n = 9), Humboldt penguins ( Spheniscus humboldti ) (n = 6), and domestic chickens (n = 16). Activated partial thromboplastin time, prothrombin time, and fibrinogen were measured as a means of comparison. Regardless of the mode of activation, clot formation in the species studied was markedly delayed compared with mammals. Because of prolonged reaction time (14.7-52.7 minutes) with kaolin and diluted tissue factor, undiluted human tissue factor was used in all avian samples because it provided the shortest reaction time. Species differed significantly in reaction time (P = .007), clotting rate (P < .001), rate of clot formation (α angle; P < .001), and maximum amplitude (P < .001) values, indicating that species-specific reference intervals are necessary. Based on these results, TEG with specific reference intervals could prove useful in evaluating avian hemostatic disorders.

  5. Terrestrial animals as invasive species and as species at risk from invasions

    Science.gov (United States)

    Deborah M. Finch; Dean Pearson; Joseph Wunderle; Wayne Arendt

    2010-01-01

    Including terrestrial animal species in the invasive species strategy plan is an important step in invasive species management. Invasions by nonindigenous species threaten nearly 50 percent of imperiled native species in the United States and are the Nation's second leading cause of species endangerment. Invasion and conversion of native habitats by exotic species...

  6. New Helicobacter species in humans.

    Science.gov (United States)

    Andersen, L P

    2001-01-01

    During the last decade several new Helicobacter species have been isolated from human gastric mucosa, fecal samples, liver, and gallbladder. Gastric corkscrew-shaped Helicobacter species: H. heilmannii is usually seen in the gastric foveolae in 0.2-0.6% of histological sections from the gastric mucosa of patients with dyspepsia in Western Europe, but it has only been cultured once. It is genetically and morphologically closely related to H. bizzozeronii and H. salmonis which are common in dogs and cats. It causes constantly active chronic gastritis and is regularly associated with peptic ulcer. Intestinal Helicobacter species: H. cinaedi, H. fennelliae, H. pullorum, H. westmeadii, H. canadensis, and 'H. rappini' have been isolated from patients with enteritis and proctitis. H. fennelliae, H. cinaedi, H. westmeadii, and 'H. rappini' have been isolated also from patients with septicemia. Studies indicate that H. cinaedi is transmitted from hamsters and that H. pullorum is common in chickens. 'H. rappini' has been isolated from sheep, dogs, and mice, whereas no animal reservoir has been found for H. fennelliae. Except for the cases of septicemia, none of these Helicobacter species have yet been proven to cause human disease, but they are suspected to play a role in inflammatory bowel diseases. Hepatobiliary Helicobacter species include several Helicobacter species isolated from bile and liver of animals, but only H. bilis has been isolated from the human gallbladder and H. pylori from the human liver. H. bilis has been isolated from dogs, cats, mice, and rats. Nonpylori Helicobacter species are usually difficult to culture and may be more frequently causes of human disease than realized today.

  7. Xiphinema krugi, Species Complex or Complex of Cryptic Species?

    Science.gov (United States)

    Oliveira, Claudio M G; Ferraz, Luiz C C B; Neilson, Roy

    2006-12-01

    Fourteen morphologically putative populations of X. krugi were clearly separated into four different profiles by RFLP analysis (Alu I and Hinf I), sequencing of the ITS-1 region, and subsequent Maximum Likelihood phylogenetic analyses. These four profiles were further supported by a principal component analysis of morphometric characters that yielded four taxonomic clusters matching those produced by the molecular data. Sequence homology was greater amongst populations that represented the same RFLP profile than between profiles and similar both between representative populations of the RFLP profiles and putative closely related Xiphinema species. This study suggests that X. krugi is a potential species complex comprised of at least four distinct genotypes.

  8. Malassezia Species and Pityriasis Versicolor

    Directory of Open Access Journals (Sweden)

    Gulin Rodoplu

    2016-01-01

    Full Text Available Malassezia species are found in part of the normal human cutaneous commensal flora, however it has been known for many years that the Malassezia yeasts are associated with a number of different human diseases ranging from pityriasis versicolor to seborrhoeic dermatitis. In addition, since the 1980s, they have been reported as causing opportunistic systemic infections. The taxonomy of Malassezia spp. has recently been modified to include 13 obligatorily lipophilic species, plus one non-obligatorily lipophilic species, which only rarely colonizes human hosts and currently the genus consist 14 species as M. furfur, M. pachydermatis, M. sympodialis, M. globosa, M. obtusa, M. slooffiae, M. restricta, M. dermatis, M. japonica, M. nana, M. yamatoensis, M. caprae, M. equina, M. cuniculi. Fastidious growth requirements of Malassezia yeasts defied the initial attempts to culture these organisms and their true identification and the relationship between different species only became apparent with the application of modern molecular techniques. The causative fungus is seen especially in such seborrheic areas as the scalp, face, trunk and upper back. Under the influence of various exogenous or endogenous predisposing factors, these yeasts change from the blastospore form to the mycelial form and become pathogenic. Diagnosis of pityriasis versicolor which is caused by Malassezia species is generally easy and lies on the basis of its clinical appearance and can be confirmed by mycological examination. The diagnosisis is mainly based on direct examination with potassium hydroxide (KOH and demonstration that represents pseudohyphae and blastoconidia as the typical %u201Cspaghetti and meatballs%u201D pattern. Characteristic features of the genus Malassezia include a distinctive morphology and an affinity for lipids in culture. Culture is necessary to recover the infecting strain, especially for epidemiologic purposes and also to test its antifungal susceptibility

  9. Molecular epidemiology of Fonsecaea species.

    Science.gov (United States)

    Najafzadeh, Mohammad Javad; Sun, Jiufeng; Vicente, Vania A; Klaassen, Corne H W; Bonifaz, Alexandro; Gerrits van den Ende, A H G; Menken, Steph B J; de Hoog, G Sybren

    2011-03-01

    To assess population diversities among 81 strains of fungi in the genus Fonsecaea that had been identified down to species level, we applied amplified fragment-length polymorphism (AFLP) technology and sequenced the internal transcribed spacer regions and the partial cell division cycle, beta-tubulin, and actin genes. Many species of the genus Fonsecaea cause human chromoblastomycosis. Strains originated from a global sampling of clinical and environmental sources in the Western Hemisphere, Asia, Africa, and Europe. According to AFLP fingerprinting, Fonsecaea isolates clustered in 5 groups corresponding with F. pedrosoi, F. monophora, and F. nubica: the latter 2 species each comprised 2 groups, and F. pedrosoi appeared to be of monophyletic origin. F. pedrosoi was found nearly exclusively in Central and South America. F. monophora and F. nubica were distributed worldwide, but both showed substantial geographic structuring. Clinical cases outside areas where Fonsecaea is endemic were probably distributed by human migration.

  10. Habitat association of Klebsiella species.

    Science.gov (United States)

    Bagley, S T

    1985-02-01

    The genus Klebsiella is seemingly ubiquitous in terms of its habitat associations. Klebsiella is a common opportunistic pathogen for humans and other animals, as well as being resident or transient flora (particularly in the gastrointestinal tract). Other habitats include sewage, drinking water, soils, surface waters, industrial effluents, and vegetation. Until recently, almost all these Klebsiella have been identified as one species, ie, K. pneumoniae. However, phenotypic and genotypic studies have shown that "K. pneumoniae" actually consists of at least four species, all with distinct characteristics and habitats. General habitat associations of Klebsiella species are as follows: K. pneumoniae--humans, animals, sewage, and polluted waters and soils; K. oxytoca--frequent association with most habitats; K. terrigena--unpolluted surface waters and soils, drinking water, and vegetation; K. planticola--sewage, polluted surface waters, soils, and vegetation; and K. ozaenae/K. rhinoscleromatis--infrequently detected (primarily with humans).

  11. Tiarosporella species: Distribution and significance

    Directory of Open Access Journals (Sweden)

    Karadžić Dragan

    2003-01-01

    Full Text Available The genus Tiarosporella consists of eight species of which four occur on conifers. These fungi differ in conidial size and in the form of appendages that occur on the distal end of the conidia (pycnospore. In Europe only the two species have been recorded. T. parca occurs on the species of the genus Picea (P. abies and P. omorika, while T. durmitorensis infests fir (Abies alba. T. parca can be considered, as an endophyte, and it sporulates only when the needles die due to a stress or old age. T. durmitorensis is a very aggressive pathogen colonizing fir needles of all ages. Together with other fungi, it leads to tree death. So far, T. durmitotensis has been found only in European silver fir stands in the National Park "Durmitor" and in the National Park "Biogradska Gora".

  12. Molecular Epidemiology of Fonsecaea Species

    Science.gov (United States)

    Najafzadeh, Mohammad Javad; Sun, Jiufeng; Vicente, Vania A.; Klaassen, Corne H.W.; Bonifaz, Alexandro; van den Ende, A.H.G. Gerrits; Menken, Steph B.J.

    2011-01-01

    To assess population diversities among 81 strains of fungi in the genus Fonsecaea that had been identified down to species level, we applied amplified fragment-length polymorphism (AFLP) technology and sequenced the internal transcribed spacer regions and the partial cell division cycle, β-tubulin, and actin genes. Many species of the genus Fonsecaea cause human chromoblastomycosis. Strains originated from a global sampling of clinical and environmental sources in the Western Hemisphere, Asia, Africa, and Europe. According to AFLP fingerprinting, Fonsecaea isolates clustered in 5 groups corresponding with F. pedrosoi, F. monophora, and F. nubica: the latter 2 species each comprised 2 groups, and F. pedrosoi appeared to be of monophyletic origin. F. pedrosoi was found nearly exclusively in Central and South America. F. monophora and F. nubica were distributed worldwide, but both showed substantial geographic structuring. Clinical cases outside areas where Fonsecaea is endemic were probably distributed by human migration. PMID:21392438

  13. Scandinavian Oncophorus (Bryopsida, Oncophoraceae: species, cryptic species, and intraspecific variation

    Directory of Open Access Journals (Sweden)

    Lars Hedenäs

    2017-05-01

    Full Text Available Scandinavian members of the acrocarpous moss genus Oncophorus were revised after field observations had suggested unrecognized diversity. Based on molecular (nuclear: internal transcribed spacers 1 and 2, ITS; plastid: trnGUCC G2 intron, trnG, rps4 gene + trnS-rps4 spacer, rps4 and morphological evidence, four morphologically distinguishable species are recognized, Oncophorus elongatus (I.Hagen Hedenäs, O. integerrimus Hedenäs sp. nov. (syn. O. virens var. elongatus Limpr., O. virens (Hedw. Brid., and O. wahlenbergii Brid. (O. sardous Herzog, syn. nov.. Oncophorus elongatus was earlier recognized, but much of its variation was hidden within O. wahlenbergii. Its circumscription is here expanded to include plants with long leaves having mostly denticulate or sharply denticulate upper margins and with long and narrow marginal cells in the basal portion of the sheathing leaf lamina. The new species O. integerrimus sp. nov. differs from O. virens in having more loosely incurved leaves and entire or almost entire upper leaf margins. Besides these characters, the species in the respective pairs differ in quantitative features of the leaf lamina cells. Several cryptic entities were found, in several cases as molecularly distinct as some of the morphologically recognizable species, and phylogeographic structure is present within O. elongatus and O. virens.

  14. Community composition and species richness of parasitoids infesting Yponomeuta species in the Netherlands

    NARCIS (Netherlands)

    Cleary, Daniel F.R.

    2004-01-01

    Parasitoid assemblages infesting Yponomeuta species in the Netherlands were investigated. Parasitoid species richness and community composition were related to host species, habitat, temporal and spatial variation. Both community structure and species richness did not differ among habitats. There

  15. Species and speciation in the fossil record

    National Research Council Canada - National Science Library

    Allmon, Warren D; Yacobucci, Margaret M

    2016-01-01

    "Although the species is one of the fundamental units of biological classification, there is remarkably little consensus among biologists about what defines a species, even within distinct subdisciplines...

  16. Seven new Malesian species of Ficus (Moraceae)

    NARCIS (Netherlands)

    Berg, C.C.

    2012-01-01

    Descriptions of seven new species, Ficus buntaensis, F. flavistipulata, F. jambiensis, F. porata, F. samarana, F. sorongensis and F. temburongensis are presented and the related species briefly discussed.

  17. Molecular Epidemiology of Fonsecaea Species

    NARCIS (Netherlands)

    Najafzadeh, M.J.; Sun, J.; Vicente, V.A.; Klaassen, C.H.W.; Bonifaz, A.; Gerrits van den Ende, A.H.G.; Menken, S.B.J.; de Hoog, G.S.

    2011-01-01

    To assess population diversities among 81 strains of fungi in the genus Fonsecaea that had been identified down to species level, we applied amplified fragment-length polymorphism (AFLP) technology and sequenced the internal transcribed spacer regions and the partial cell division cycle, β-tubulin,

  18. Chromosome synteny in cucumis species

    Science.gov (United States)

    Cucumber, Cucumis sativus L. (2n = 2x = 14) and melon, C. melo L. (2n = 2x = 24) are two important vegetable species in the genus Cucumis (family Cucurbitaceae). Two inter-fertile botanical varieties with 14 chromosomes, the cultivated C. sativus var. sativus L. and the wild C. sativus var. hardwick...

  19. Phylogenetic relationships among Maloideae species

    Science.gov (United States)

    The Maloideae is a highly diverse sub-family of the Rosaceae containing several agronomically important species (Malus sp. and Pyrus sp.) and their wild relatives. Previous phylogenetic work within the group has revealed extensive intergeneric hybridization and polyploidization. In order to develop...

  20. Thromboelastography in Selected Avian Species

    DEFF Research Database (Denmark)

    Andersen, Sophie Susanna Strindberg; Nielsen, Tenna W; Ribeiro, Ângela M

    2015-01-01

    . Regardless of the mode of activation, clot formation in the species studied was markedly delayed compared with mammals. Because of prolonged reaction time (14.7-52.7 minutes) with kaolin and diluted tissue factor, undiluted human tissue factor was used in all avian samples because it provided the shortest...

  1. Nickel Homeostasis in Helicobacter Species

    NARCIS (Netherlands)

    J. Stoof (Jeroen)

    2011-01-01

    textabstractGastric Helicobacter species are adapted to colonize the acidic environment of the stomach. Colonization with H pylori is life long if untreated, and can lead to gastritis, peptic ulcer disease and eventually to gastric cancer. Although H pylori is sensitive to many antibiotics in vitro,

  2. Botrytis species on bulb crops

    NARCIS (Netherlands)

    Lorbeer, J.W.; Seyb, A.M.; Boer, de M.; Ende, van den J.E.

    2007-01-01

    Abstract. A number of Botrytis species are pathogens of bulb crops. Botrytis squamosa (teleomorph= Botrytotinia squamosa) causal agent of botrytis leaf blight and B. allii the causal agent of botrytis neck rot are two of the most important fungal diseases of onion. The taxonomics of several of the n

  3. Man...An Endangered Species?

    Science.gov (United States)

    Department of the Interior, Washington, DC.

    The general theme of this 1968 yearbook is that man is a threatened species, facing overpopulation and unbridled technology - both self induced. The presentation is broad, relating to many aspects of conservation and natural resources in the United States in a descriptive, non-technical style. The yearbook is divided into major topics: Land…

  4. Man...An Endangered Species?

    Science.gov (United States)

    Department of the Interior, Washington, DC.

    The general theme of this 1968 yearbook is that man is a threatened species, facing overpopulation and unbridled technology - both self induced. The presentation is broad, relating to many aspects of conservation and natural resources in the United States in a descriptive, non-technical style. The yearbook is divided into major topics: Land…

  5. Fifteen new species of Penicillium

    NARCIS (Netherlands)

    Visagie, C.M.; Renaud, J.B.; Burgess, K.M.N.; Malloch, D.W.; Clark, D.; Ketch, L.; Urb, M.; Louis-Seize, G.; Assabgui, R.; Sumarah, M.W.; Seifert, K.A.

    2016-01-01

    We introduce 15 new species of Penicillium isolated from a diverse range of locations, including Canada, Costa Rica, Germany, Italy, New Zealand, Tanzania, USA and the Dry Valleys of Antarctica, from a variety of habitats, including leaf surfaces in tropical rain forests, soil eaten by chimpanzees,

  6. 76 FR 74778 - Endangered Species

    Science.gov (United States)

    2011-12-01

    ... National Oceanic and Atmospheric Administration RIN 0648-XA850 Endangered Species AGENCY: National Marine..., notice was published in the Federal Register (76 FR 33703) that a request for a scientific research... with passive integrated transponder (PIT) tags and Floy tags, if untagged; and sample genetic fin...

  7. Optimal conservation of migratory species.

    Directory of Open Access Journals (Sweden)

    Tara G Martin

    Full Text Available BACKGROUND: Migratory animals comprise a significant portion of biodiversity worldwide with annual investment for their conservation exceeding several billion dollars. Designing effective conservation plans presents enormous challenges. Migratory species are influenced by multiple events across land and sea-regions that are often separated by thousands of kilometres and span international borders. To date, conservation strategies for migratory species fail to take into account how migratory animals are spatially connected between different periods of the annual cycle (i.e. migratory connectivity bringing into question the utility and efficiency of current conservation efforts. METHODOLOGY/PRINCIPAL FINDINGS: Here, we report the first framework for determining an optimal conservation strategy for a migratory species. Employing a decision theoretic approach using dynamic optimization, we address the problem of how to allocate resources for habitat conservation for a Neotropical-Nearctic migratory bird, the American redstart Setophaga ruticilla, whose winter habitat is under threat. Our first conservation strategy used the acquisition of winter habitat based on land cost, relative bird density, and the rate of habitat loss to maximize the abundance of birds on the wintering grounds. Our second strategy maximized bird abundance across the entire range of the species by adding the constraint of maintaining a minimum percentage of birds within each breeding region in North America using information on migratory connectivity as estimated from stable-hydrogen isotopes in feathers. We show that failure to take into account migratory connectivity may doom some regional populations to extinction, whereas including information on migratory connectivity results in the protection of the species across its entire range. CONCLUSIONS/SIGNIFICANCE: We demonstrate that conservation strategies for migratory animals depend critically upon two factors: knowledge of

  8. Species recovery in the United States: Increasing the effectiveness of the Endangered Species Act

    Science.gov (United States)

    Daniel M. Evans; Judy P. Che-Castaldo; Deborah Crouse; Frank W. Davis; Rebecca Epanchin-Niell; Curtis H. Flather; R. Kipp Frohlich; Dale D. Goble; Ya-Wei Li; Timothy D. Male; Lawrence L. Master; Matthew P. Moskwik; Maile C. Neel; Barry R. Noon; Camille Parmesan; Mark W. Schwartz; J. Michael Scott; Byron K. Williams

    2016-01-01

    The Endangered Species Act (ESA) has succeeded in shielding hundreds of species from extinction and improving species recovery over time. However, recovery for most species officially protected by the ESA - i.e., listed species - has been harder to achieve than initially envisioned. Threats to species are persistent and pervasive, funding has been insufficient...

  9. Modelling biological invasions: species traits, species interactions, and habitat heterogeneity.

    Science.gov (United States)

    Cannas, Sergio A; Marco, Diana E; Páez, Sergio A

    2003-05-01

    In this paper we explore the integration of different factors to understand, predict and control ecological invasions, through a general cellular automaton model especially developed. The model includes life history traits of several species in a modular structure interacting multiple cellular automata. We performed simulations using field values corresponding to the exotic Gleditsia triacanthos and native co-dominant trees in a montane area. Presence of G. triacanthos juvenile bank was a determinant condition for invasion success. Main parameters influencing invasion velocity were mean seed dispersal distance and minimum reproductive age. Seed production had a small influence on the invasion velocity. Velocities predicted by the model agreed well with estimations from field data. Values of population density predicted matched field values closely. The modular structure of the model, the explicit interaction between the invader and the native species, and the simplicity of parameters and transition rules are novel features of the model.

  10. Allelopathy of plant species of pharmaceutical importance to cultivated species

    Directory of Open Access Journals (Sweden)

    Álisson Sobrinho Maranho

    2012-11-01

    Full Text Available This study aimed to identify possible allelopathic effects of leaf aqueous extracts of Baccharis dracunculifolia DC., Pilocarpus pennatifolius Lem., Cyperus rotundus L., Morus rubra L., Casearia sylvestris Sw., and Plectranthus barbatus Andr. on the germination and initial growth of Lactuca sativa L., Brassica oleracea L. cv. capitata, B. oleracea L. cv. italica, B. pekinenses L., B. campestris L., Lycopersicum esculentum Miller, and Eruca sativa L. To obtain the aqueous extracts, leaves previously dried at a 1g.10mL-1 concentration were used, diluted in six solutions (10, 30, 50, 70, 90, and 100% and compared to control, distilled water, with five replications of 10 seeds for all vegetable species. The aqueous extracts of all species showed allelopathic potential for germination of seeds, the germination speed index, and the initial growth of shoots and roots of vegetable crops. The aqueous extracts of C. rotundus and P. barbatus promoted lower and higher allelopathic effects, respectively, and the vegetal structure mostly affected by the extracts was the primary root. The results indicate the existence of allelopathic potential in the species tested, so there’s a need for adopting care procedures when cultivating vegetables with them.

  11. ICRAF Species Switchboard. Version 1.2

    DEFF Research Database (Denmark)

    Kindt, R.; Ordonez, J.; Smith, E.;

    2015-01-01

    The current version of the Agroforestry Species Switchboard documents the presence of a total of 26,135 plant species (33,813 species including synonyms) across 19 web-based databases. When available, hyperlinks to information on the selected species in particular databases are provided. In total...

  12. The myth of plant species saturation

    Science.gov (United States)

    Thomas J. Stohlgren; David T. Barnett; Catherine S. Jarnevich; Curtis Flather; John Kartesz

    2008-01-01

    Plant species assemblages, communities or regional floras might be termed saturated when additional immigrant species are unsuccessful at establishing due to competitive exclusion or other inter-specific interactions, or when the immigration of species is off-set by extirpation of species. This is clearly not the case for state, regional or national floras in the USA...

  13. ICRAF Species Switchboard. Version 1.2

    DEFF Research Database (Denmark)

    Kindt, R.; Ordonez, J.; Smith, E.

    2015-01-01

    The current version of the Agroforestry Species Switchboard documents the presence of a total of 26,135 plant species (33,813 species including synonyms) across 19 web-based databases. When available, hyperlinks to information on the selected species in particular databases are provided. In total...

  14. A new species of Sporothrix from Kuwait

    NARCIS (Netherlands)

    Moustafa, A.F.

    1981-01-01

    During an ecological study of fungi of the tidal mudflats in Kuwait, a Sporothrix species has been recorded twice, in 1977 and 1980. It differs from other species of the genus (de Hoog, 1974, 1978) in several characters and is here described as a new species. A comparison with similar species of the

  15. Comparative genomics of Listeria species.

    Science.gov (United States)

    Glaser, P; Frangeul, L; Buchrieser, C; Rusniok, C; Amend, A; Baquero, F; Berche, P; Bloecker, H; Brandt, P; Chakraborty, T; Charbit, A; Chetouani, F; Couvé, E; de Daruvar, A; Dehoux, P; Domann, E; Domínguez-Bernal, G; Duchaud, E; Durant, L; Dussurget, O; Entian, K D; Fsihi, H; García-del Portillo, F; Garrido, P; Gautier, L; Goebel, W; Gómez-López, N; Hain, T; Hauf, J; Jackson, D; Jones, L M; Kaerst, U; Kreft, J; Kuhn, M; Kunst, F; Kurapkat, G; Madueno, E; Maitournam, A; Vicente, J M; Ng, E; Nedjari, H; Nordsiek, G; Novella, S; de Pablos, B; Pérez-Diaz, J C; Purcell, R; Remmel, B; Rose, M; Schlueter, T; Simoes, N; Tierrez, A; Vázquez-Boland, J A; Voss, H; Wehland, J; Cossart, P

    2001-10-26

    Listeria monocytogenes is a food-borne pathogen with a high mortality rate that has also emerged as a paradigm for intracellular parasitism. We present and compare the genome sequences of L. monocytogenes (2,944,528 base pairs) and a nonpathogenic species, L. innocua (3,011,209 base pairs). We found a large number of predicted genes encoding surface and secreted proteins, transporters, and transcriptional regulators, consistent with the ability of both species to adapt to diverse environments. The presence of 270 L. monocytogenes and 149 L. innocua strain-specific genes (clustered in 100 and 63 islets, respectively) suggests that virulence in Listeria results from multiple gene acquisition and deletion events.

  16. Fifteen new species of Penicillium.

    Science.gov (United States)

    Visagie, C M; Renaud, J B; Burgess, K M N; Malloch, D W; Clark, D; Ketch, L; Urb, M; Louis-Seize, G; Assabgui, R; Sumarah, M W; Seifert, K A

    2016-06-01

    We introduce 15 new species of Penicillium isolated from a diverse range of locations, including Canada, Costa Rica, Germany, Italy, New Zealand, Tanzania, USA and the Dry Valleys of Antarctica, from a variety of habitats, including leaf surfaces in tropical rain forests, soil eaten by chimpanzees, infrabuccal pockets of carpenter ants, intestinal contents of caterpillars and soil. The new species are classified in sections Aspergilloides (1), Canescentia (2), Charlesia (1), Exilicaulis (3), Lanata-Divaricata (7) and Stolkia (1). Each is characterised and described using classical morphology, LC-MS based extrolite analyses and multigene phylogenies based on ITS, BenA and CaM. Significant extrolites detected include andrastin, pulvilloric acid, penitrem A and citrinin amongst many others.

  17. Charcoal anatomy of forest species

    Directory of Open Access Journals (Sweden)

    Graciela Inés Bolzon de Muñiz1

    2012-09-01

    Full Text Available Vegetal charcoal retains the anatomical structure of the wood and may permit its botanical identification, which depends on species characteristics, the charcoal fragments size and preservation state. Anatomical characterization of ten forest species charcoal was done envisaging the identification and control of illegal charcoal. Differences between gymnosperms and angiosperms are evident in carbonized wood. Vessel diameter was statistically different between wood and charcoal in Vatairea guianensis, Mezilaurus itauba, Calophyllum brasiliense e Qualea cf. acuminata, and vessel frequency in Vatairea guianensis, Manilkara huberi, Qualea cf. acuminata e Simarouba amara. The anatomical structure from wood, in general aspects, is constant during carbonization process using temperature of 450°C, being possible to identify the material by using its cellular components.

  18. Two living species of coelacanths?

    OpenAIRE

    Holder, Mark T.; Erdmann, Mark V.; Wilcox, Thomas P; Caldwell, Roy L.; David M Hillis

    1999-01-01

    During the period of September 1997 through July 1998, two coelacanth fishes were captured off Manado Tua Island, Sulawesi, Indonesia. These specimens were caught almost 10,000 km from the only other known population of living coelacanths, Latimeria chalumnae, near the Comores. The Indonesian fish was described recently as a new species, Latimeria menadoensis, based on morphological differentiation and DNA sequence divergence in fragments of the cytochrome b and 12S rRNA genes. We have obtain...

  19. Native Terrestrial Animal Species Richness

    Science.gov (United States)

    These data represent predicted current distributions of all native mammals, birds, reptiles, amphibians and butterflies in the Middle-Atlantic region. The data are available for both 8-digit HUCs and EMAP hexagons and represent total species counts for each spatial unit. More information about these resources, including the variables used in this study, may be found here: https://edg.epa.gov/data/Public/ORD/NERL/ReVA/ReVA_Data.zip.

  20. Recognizing species, present and past.

    Science.gov (United States)

    Tattersall, Ian

    2014-01-01

    Nobody disputes that nature is meaningfully "packaged" in some way. But debate persists over exactly how (and even whether) the boundaries dividing taxa should (can) be drawn. At one end of the scale, some zealots abstrusely deny real existence to higher taxa.(1) At the other, laborers at the taxonomic rock-face confront genuine challenges in recognizing and delineating the species that systematists agree constitute the most fundamental unit of taxonomic analysis.

  1. Arsenic Species in Marine Samples

    OpenAIRE

    Francesconi, Kevin A.; Edmonds, John S.

    1998-01-01

    Arsenic occurs in seawater, in predominantly inorganic forms, at concentrations of about 1-2 μg/L. These concentrations are higher than those of most other potentially toxic metals and semimetals. Marine organisms have coped by exploiting the rich organic chemistry of arsenic to transform inorganic arsenic into a range of essentially non-toxic organoarsenic compounds. The resulting diversity of arsenic species found in marine samples is reviewed together with an overview of analytical meth...

  2. Cyanogenesis in Lotus and Trifolium species

    OpenAIRE

    Halina Blaim; Edmunt Nowacki

    2015-01-01

    The occurrence of cyanogenic plants was determined in 48 Trifolium species, 12 Lotus species, in wild population as well as in varieties of T. repens L. and Loins corniculatus L. species. In the genus Trifolium only T. nigrescens Viv. proved to be high-cyanogenic, all the remaining species are acyanogenic or low-cyanogenic. In the T. repens species varieties and wild populations include an insignificant per cent of cyanogenic plants.The genus Lotus comprises both high-cyanogenic and acyanogen...

  3. Floral reward in Ranunculaceae species

    Directory of Open Access Journals (Sweden)

    Bożena Denisow

    2016-04-01

    Full Text Available Floral reward is important in ecological and evolutionary perspectives and essential in pollination biology. For example, floral traits, nectar and pollen features are essential for understanding the functional ecology, the dynamics of pollen transport, competition for pollinator services, and patterns of specialization and generalization in plant–pollinator interactions. We believe to present a synthetic description in the field of floral reward in Ranunculaceae family important in pollination biology and indicating connections between ecological and evolutionary approaches. The links between insect visitors’ behaviour and floral reward type and characteristics exist. Ranunculaceae is a family of aboot 1700 species (aboot 60 genera, distributed worldwide, however the most abundant representatives are in temperate and cool regions of the northern and southern hemispheres. The flowers are usually radially symmetric (zygomorphic and bisexual, but in Aconitum, Aquilegia are bilaterally symmetric (zygomorphic. Most Ranunculaceae flowers offer no nectar, only pollen (e.g., Ranunculus, Adonis vernalis, Thalictrum, but numerous species create trophic niches for different wild pollinators (e.g. Osmia, Megachile, Bombus, Andrena (Denisow et al. 2008. Pollen is a source of protein, vitamins, mineral salts, organic acids and hormones, but the nutritional value varies greatly between different plant species. The pollen production can differ significantly between Ranunculacea species. The mass of pollen produced in anthers differ due to variations in the number of developed anthers. For example, interspecies differences are considerable, 49 anthers are noted in Aquilegia vulgaris, 70 anthers in Ranunculus lanuginosus, 120 in Adonis vernalis. A significant intra-species differences’ in the number of anthers are also noted (e.g. 41 to 61 in Aquilegia vulgaris, 23-45 in Ranunculus cassubicus. Pollen production can be up to 62 kg per ha for Ranunculus acer

  4. Increased diversification rates follow shifts to bisexuality in liverworts.

    Science.gov (United States)

    Laenen, Benjamin; Machac, Antonin; Gradstein, S Robbert; Shaw, Blanka; Patiño, Jairo; Désamoré, Aurélie; Goffinet, Bernard; Cox, Cymon J; Shaw, A Jonathan; Vanderpoorten, Alain

    2016-05-01

    Shifts in sexual systems are one of the key drivers of species diversification. In contrast to angiosperms, unisexuality prevails in bryophytes. Here, we test the hypotheses that bisexuality evolved from an ancestral unisexual condition and is a key innovation in liverworts. We investigate whether shifts in sexual systems influence diversification using hidden state speciation and extinction analysis (HiSSE). This new method compares the effects of the variable of interest to the best-fitting latent variable, yielding robust and conservative tests. We find that the transitions in sexual systems are significantly biased toward unisexuality, even though bisexuality is coupled with increased diversification. Sexual systems are strongly conserved deep within the liverwort tree but become much more labile toward the present. Bisexuality appears to be a key innovation in liverworts. Its effects on diversification are presumably mediated by the interplay of high fertilization rates, massive spore production and long-distance dispersal, which may separately or together have facilitated liverwort speciation, suppressed their extinction, or both. Importantly, shifts in liverwort sexual systems have the opposite effect when compared to angiosperms, leading to contrasting diversification patterns between the two groups. The high prevalence of unisexuality among liverworts suggests, however, a strong selection for sexual dimorphism. © 2016 The Authors. New Phytologist © 2016 New Phytologist Trust.

  5. Alien species in the Finnish weed flora

    Directory of Open Access Journals (Sweden)

    T. HYVÖNEN

    2008-12-01

    Full Text Available The present study aimed at assessing the invasion of alien weed species in Finland based on a review of their occurrence in the Finnish weed flora. The evaluation was conducted for the three phases of the invasion process, i.e. introduction, naturalization and invasion. The literature review revealed that 815 alien weed species occur in Finland of which 314 are regarded as naturalized. Based on their occurrence in different climate zones, the risk of naturalization of new harmful alien weed species was deemed low for those species not currently found in Finland, but higher for species occurring as casual aliens in Finland. In the latter group, 10 species of concern were detected. Exploration of the distribution patterns of naturalized species within Finland revealed species occupancy to be dependent on the residence time of the species. Established neophytes can be expected to extend their ranges and to increase occupation of agricultural habitats in the future.;

  6. Natural Constraints to Species Diversification.

    Science.gov (United States)

    Lewitus, Eric; Morlon, Hélène

    2016-08-01

    Identifying modes of species diversification is fundamental to our understanding of how biodiversity changes over evolutionary time. Diversification modes are captured in species phylogenies, but characterizing the landscape of diversification has been limited by the analytical tools available for directly comparing phylogenetic trees of groups of organisms. Here, we use a novel, non-parametric approach and 214 family-level phylogenies of vertebrates representing over 500 million years of evolution to identify major diversification modes, to characterize phylogenetic space, and to evaluate the bounds and central tendencies of species diversification. We identify five principal patterns of diversification to which all vertebrate families hold. These patterns, mapped onto multidimensional space, constitute a phylogenetic space with distinct properties. Firstly, phylogenetic space occupies only a portion of all possible tree space, showing family-level phylogenies to be constrained to a limited range of diversification patterns. Secondly, the geometry of phylogenetic space is delimited by quantifiable trade-offs in tree size and the heterogeneity and stem-to-tip distribution of branching events. These trade-offs are indicative of the instability of certain diversification patterns and effectively bound speciation rates (for successful clades) within upper and lower limits. Finally, both the constrained range and geometry of phylogenetic space are established by the differential effects of macroevolutionary processes on patterns of diversification. Given these properties, we show that the average path through phylogenetic space over evolutionary time traverses several diversification stages, each of which is defined by a different principal pattern of diversification and directed by a different macroevolutionary process. The identification of universal patterns and natural constraints to diversification provides a foundation for understanding the deep-time evolution of

  7. The Invasive Species Forecasting System

    Science.gov (United States)

    Schnase, John; Most, Neal; Gill, Roger; Ma, Peter

    2011-01-01

    The Invasive Species Forecasting System (ISFS) provides computational support for the generic work processes found in many regional-scale ecosystem modeling applications. Decision support tools built using ISFS allow a user to load point occurrence field sample data for a plant species of interest and quickly generate habitat suitability maps for geographic regions of management concern, such as a national park, monument, forest, or refuge. This type of decision product helps resource managers plan invasive species protection, monitoring, and control strategies for the lands they manage. Until now, scientists and resource managers have lacked the data-assembly and computing capabilities to produce these maps quickly and cost efficiently. ISFS focuses on regional-scale habitat suitability modeling for invasive terrestrial plants. ISFS s component architecture emphasizes simplicity and adaptability. Its core services can be easily adapted to produce model-based decision support tools tailored to particular parks, monuments, forests, refuges, and related management units. ISFS can be used to build standalone run-time tools that require no connection to the Internet, as well as fully Internet-based decision support applications. ISFS provides the core data structures, operating system interfaces, network interfaces, and inter-component constraints comprising the canonical workflow for habitat suitability modeling. The predictors, analysis methods, and geographic extents involved in any particular model run are elements of the user space and arbitrarily configurable by the user. ISFS provides small, lightweight, readily hardened core components of general utility. These components can be adapted to unanticipated uses, are tailorable, and require at most a loosely coupled, nonproprietary connection to the Web. Users can invoke capabilities from a command line; programmers can integrate ISFS's core components into more complex systems and services. Taken together, these

  8. VIDAS Listeria species Xpress (LSX).

    Science.gov (United States)

    Johnson, Ronald; Mills, John

    2013-01-01

    The AOAC GovVal study compared the VIDAS Listeria species Xpress (LSX) to the Health Products and Food Branch MFHPB-30 reference method for detection of Listeria on stainless steel. The LSX method utilizes a novel and proprietary enrichment media, Listeria Xpress broth, enabling detection of Listeria species in environmental samples with the automated VIDAS in a minimum of 26 h. The LSX method also includes the use of the chromogenic media, chromID Ottaviani Agosti Agar (OAA) and chromID Lmono for confirmation of LSX presumptive results. In previous AOAC validation studies comparing VIDAS LSX to the U.S. Food and Drug Administration's Bacteriological Analytical Manual (FDA-BAM) and the U.S. Department of Agriculture-Food Safety and Inspection Service (USDA-FSIS) reference methods, the LSX method was approved as AOAC Official Method 2010.02 for the detection of Listeria species in dairy products, vegetables, seafood, raw meats and poultry, and processed meats and poultry, and as AOAC Performance Tested Method 100501 in a variety of foods and on environmental surfaces. The GovVal comparative study included 20 replicate test portions each at two contamination levels for stainless steel where fractionally positive results (5-15 positive results/20 replicate portions tested) were obtained by at least one method at one level. Five uncontaminated controls were included. In the stainless steel artificially contaminated surface study, there were 25 confirmed positives by the VIDAS LSX assay and 22 confirmed positives by the standard culture methods. Chi-square analysis indicated no statistical differences between the VIDAS LSX method and the MFHPB-30 standard methods at the 5% level of significance. Confirmation of presumptive LSX results with the chromogenic OAA and Lmono media was shown to be equivalent to the appropriate reference method agars. The data in this study demonstrate that the VIDAS LSX method is an acceptable alternative method to the MFHPB-30 standard

  9. Biodiversity conservation including uncharismatic species

    DEFF Research Database (Denmark)

    Muñoz, Joaquin

    2007-01-01

    Recent papers mention ideas on the topics of biodiversity conservation strategies and priorities (Redford et al. 2003; Lamoreux et al. 2006; Rodrı´guez et al. 2006), the current status of biodiversity (Loreau et al. 2006), the obligations of conservation biologists regarding management policies...... (Chapron 2006; Schwartz 2006), and the main threats to biodiversity (including invasive species) (Bawa 2006). I suggest, however, that these articles do not really deal with biodiversity. Rather, they all focus on a few obviously charismatic groups (mammals, birds, some plants, fishes, human culture...

  10. The floral transcriptomes of four bamboo species (Bambusoideae; Poaceae): support for common ancestry among woody bamboos.

    Science.gov (United States)

    Wysocki, William P; Ruiz-Sanchez, Eduardo; Yin, Yanbin; Duvall, Melvin R

    2016-05-20

    Next-generation sequencing now allows for total RNA extracts to be sequenced in non-model organisms such as bamboos, an economically and ecologically important group of grasses. Bamboos are divided into three lineages, two of which are woody perennials with bisexual flowers, which undergo gregarious monocarpy. The third lineage, which are herbaceous perennials, possesses unisexual flowers that undergo annual flowering events. Transcriptomes were assembled using both reference-based and de novo methods. These two methods were tested by characterizing transcriptome content using sequence alignment to previously characterized reference proteomes and by identifying Pfam domains. Because of the striking differences in floral morphology and phenology between the herbaceous and woody bamboo lineages, MADS-box genes, transcription factors that control floral development and timing, were characterized and analyzed in this study. Transcripts were identified using phylogenetic methods and categorized as A, B, C, D or E-class genes, which control floral development, or SOC or SVP-like genes, which control the timing of flowering events. Putative nuclear orthologues were also identified in bamboos to use as phylogenetic markers. Instances of gene copies exhibiting topological patterns that correspond to shared phenotypes were observed in several gene families including floral development and timing genes. Alignments and phylogenetic trees were generated for 3,878 genes and for all genes in a concatenated analysis. Both the concatenated analysis and those of 2,412 separate gene trees supported monophyly among the woody bamboos, which is incongruent with previous phylogenetic studies using plastid markers.

  11. Two living species of coelacanths?

    Science.gov (United States)

    Holder, Mark T.; Erdmann, Mark V.; Wilcox, Thomas P.; Caldwell, Roy L.; Hillis, David M.

    1999-01-01

    During the period of September 1997 through July 1998, two coelacanth fishes were captured off Manado Tua Island, Sulawesi, Indonesia. These specimens were caught almost 10,000 km from the only other known population of living coelacanths, Latimeria chalumnae, near the Comores. The Indonesian fish was described recently as a new species, Latimeria menadoensis, based on morphological differentiation and DNA sequence divergence in fragments of the cytochrome b and 12S rRNA genes. We have obtained the sequence of 4,823 bp of mitochondrial DNA from the same specimen, including the entire genes for cytochrome b, 12S rRNA, 16S rRNA, four tRNAs, and the control region. The sequence is 4.1% different from the published sequence of an animal captured from the Comores, indicating substantial divergence between the Indonesian and Comorean populations. Nine morphological and meristic differences are purported to distinguish L. menadoensis and L. chalumnae, based on comparison of a single specimen of L. menadoensis to a description of five individuals of L. chalumnae from the Comores. A survey of the literature provided data on 4 of the characters used to distinguish L. menadoensis from L. chalumnae from an additional 16 African coelacanths; for all 4 characters, the Indonesian sample was within the range of variation reported for the African specimens. Nonetheless, L. chalumnae and L. menadoensis appear to be separate species based on divergence of mitochondrial DNA. PMID:10535971

  12. Automated bioacoustic identification of species

    Directory of Open Access Journals (Sweden)

    David Chesmore

    2004-06-01

    Full Text Available Research into the automated identification of animals by bioacoustics is becoming more widespread mainly due to difficulties in carrying out manual surveys. This paper describes automated recognition of insects (Orthoptera using time domain signal coding and artificial neural networks. Results of field recordings made in the UK in 2002 are presented which show that it is possible to accurately recognize 4 British Orthoptera species in natural conditions under high levels of interference. Work is under way to increase the number of species recognized.Pesquisas sobre a identificação automatizada de animais através da bioacústica estão se ampliando, principalmente em vista das dificuldades para realizar levantamentos diretos. Este artigo descreve o reconhecimento automático de insetos Orthoptera utilizando a codificação de sinal no domínio temporal e redes neurais artificiais. Resultados de registros sonoros feitos no campo no Reino Unido em 2002 são apresentados, mostrando ser possível reconhecer corretamente 4 espécies britânicas de Orthoptera em condições naturais com altos níveis de interferências. Estão em andamento trabalhos para aumentar o número de espécies identificadas.

  13. Why some plant species are rare.

    Science.gov (United States)

    Wieger Wamelink, G W; Wamelink, G W Weiger; Goedhart, Paul W; Frissel, Joep; Frissel, Josep Y

    2014-01-01

    Biodiversity, including plant species diversity, is threatened worldwide as a result of anthropogenic pressures such as an increase of pollutants and climate change. Rare species in particular are on the verge of becoming extinct. It is still unclear as to why some plant species are rare and others are not. Are they rare due to: intrinsic reasons, dispersal capacity, the effects of management or abiotic circumstances? Habitat preference of rare plant species may play an important role in determining why some species are rare. Based on an extensive data set of soil parameters we investigated if rarity is due to a narrow habitat preference for abiotic soil parameters. For 23 different abiotic soil parameters, of which the most influential were groundwater-table, soil-pH and nutrient-contents, we estimated species responses for common and rare species. Based on the responses per species we calculated the range of occurrence, the range between the 5 and 95 percentile of the response curve giving the habitat preference. Subsequently, we calculated the average response range for common and rare species. In addition, we designed a new graphic in order to provide a better means for presentation of the results. The habitat preferences of rare species for abiotic soil conditions are significantly narrower than for common species. Twenty of the twenty-three abiotic parameters showed on average significantly narrower habitat preferences for rare species than for common species; none of the abiotic parameters showed on average a narrower habitat preference for common species. The results have major implications for the conservation of rare plant species; accordingly management and nature development should be focussed on the maintenance and creation of a broad range of environmental conditions, so that the requirements of rare species are met. The conservation of (abiotic) gradients within ecosystems is particularly important for preserving rare species.

  14. Molecular Diagnosis of Pathogenic Sporothrix Species

    NARCIS (Netherlands)

    Rodrigues, Anderson Messias; de Hoog, G Sybren; de Camargo, Zoilo Pires

    2015-01-01

    BACKGROUND: Sporotrichosis is a chronic (sub)cutaneous infection caused by thermodimorphic fungi in the order, Ophiostomatales. These fungi are characterized by major differences in routes of transmission, host predilections, species virulence, and susceptibilities to antifungals. Sporothrix species

  15. Tetrameranthus (Annonaceae revisited including a new species

    Directory of Open Access Journals (Sweden)

    Lubbert Y.Th. Westra

    2012-04-01

    Full Text Available The taxonomic revision of the infrequently collected genus Tetrameranthus by Westra (1985 is updated. A new species is described from French Guiana and Amapá, Brazil, increasing the number of species in this genus to seven.

  16. Assessing Pesticides under the Endangered Species Act

    Science.gov (United States)

    EPA’s pesticide risk assessment and regulatory processes ensure that protections are in place for all populations of non-target species. We have developed risk assessment procedures to determine potential for harm to individuals of a listed species.

  17. SIS - Species and Stock Administrative Data Set

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Species and Stock Administrative data set within the Species Information System (SIS) defines entities within the database that serve as the basis for recording...

  18. Species concepts do matter in nematology.

    Science.gov (United States)

    Ferris, V R

    1999-06-01

    Nematology is a taxon-based science, and a correct understanding of species and their relationships is basic to all nematological research. Modern methods of systematic analysis have reshaped issues concerning species recognition.

  19. SPECIES DISTRBUTION WITHIN RIPARIAN LANDCAPE ALONG ...

    African Journals Online (AJOL)

    Osondu

    2011-12-30

    Dec 30, 2011 ... The study examines species density and diversity distribution in riparian landscape along 18km stretch of. Mayo Kam. ... Result of species distribution revealed mean densities and diversities in zones A ..... map-based models.

  20. Anaho Island: Mammalian species richness report

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This study assessed the mammalian species richness on Anaho Island using live trapping between July 18th and July 23rd 2005. The last mammalian species richness...

  1. New insights into the species problem

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    Historical opinions of the "species problem" are briefly reviewed, and four salient stages are recognized according to origin of species concepts. We propose that species is the unit preserving superior gene assembly and is maintained by specific mechanisms. Based on characteristics of plant evolution, we assume that understanding plant species may include three stages, i.e. morphological recognition stage, multidisciplinary verification stage, and illuminating mechanisms preserving superior gene assembly.

  2. New species of Cystolepiota from China

    Directory of Open Access Journals (Sweden)

    Meng-Lin Xu

    2016-10-01

    Full Text Available In this paper, a new species, Cystolepiota pseudofumosifolia, is introduced. C. pseudofumosifolia is characterized by granulose or powdery pileus with an anatomic structure that is loosely globose, as well as ellipsoid cells in chains in the pileus covering the cheilocystidia. This new species is compared to the related and similar Cystolepiota species in morphology and molecular phylogeny based on Internal transcribed spacer sequences. Both types of data support our specimens as a new species in the genus Cystolepiota.

  3. Linking Keystone Species and Functional Groups: A New Operational Definition of the Keystone Species Concept

    Directory of Open Access Journals (Sweden)

    Robert D. Davic

    2003-07-01

    Full Text Available The concept of the "keystone species" is redefined to allow for the a priori prediction of these species within ecosystems. A keystone species is held to be a strongly interacting species whose top-down effect on species diversity and competition is large relative to its biomass dominance within a functional group. This operational definition links the community importance of keystone species to a specific ecosystem process, e.g., the regulation of species diversity, within functional groups at lower trophic levels that are structured by competition for a limited resource. The a priori prediction of keystone species has applied value for the conservation of natural areas.

  4. The Gilbertiodendron ogoouense species complex (Leguminosae

    NARCIS (Netherlands)

    Burgt, van der X.M.; Mackinder, B.A.; Wieringa, J.J.; Estrella, de la Manuel

    2015-01-01

    The Gilbertiodendron ogoouense species complex consists of 14 tree species. Eight species are here newly described and one is here reinstated: G. bambolense Burgt; G. breteleri Burgt; G. ebo Burgt & Mackinder; G. ecoukense (Pellegr.) Burgt; G. maximum Burgt & Wieringa; G. minkebense Burgt

  5. The South African Species of Commiphora

    Directory of Open Access Journals (Sweden)

    J. J.A. van der Walt

    1973-09-01

    Full Text Available A revision of the South African species of Commiphora (Burseraceae is presented in which 2 keys are provided to the 18 species recognized. A comprehensive morphological study, including an anatomical study of the stems and leaves, was regarded as essential for an accurate delimitation of the different species. Maps, sketches and photographs serve for illustration.

  6. Options in dealing with marine alien species

    NARCIS (Netherlands)

    Pelt-Heerschap, van H.M.L.; Sneekes, A.C.; Foekema, E.M.

    2015-01-01

    Invasive species can have strong impact on the local ecosystem, not only substantial impact on the local ecosystem, but also on economy and human health. This review on marine alien species outlines aspects of prevention, eradication and control strategies. When managing invasive species, prevention

  7. Biology, speciation, and utilization of peanut species

    Science.gov (United States)

    The genus Arachis has a large number of highly diverse species. Large collections of cultivated peanut exist at multiple locations and several hundreds of wild species are maintained in germplasm banks. Many of the species have been characterized for agronomic traits, but much of the germplasm colle...

  8. Eremophilanes and Pyrrolizidine Alkaloids of Senecioneae Species

    OpenAIRE

    2014-01-01

    The chemical study of two species of the tribe Senecioneae afforded two eremophilanes and two pyrrolizidine alkaloids from Se - necio subauriculatus and four modified eremophilanes from Roldana oaxacana . The chemistry of these species is in accord with that re - ported for species of Senecio and Roldana studied so far, and therefore, with the already described for the tribe Senecioneae.

  9. Brachyspira Species and Gastroenteritis in Humans

    NARCIS (Netherlands)

    Westerman, L.J.; Boer, de R.F.; Roelfsema, J.H.; Friesema, I.H.M.; Kortbeek, L.M.; Wagenaar, J.A.; Bonten, M.J.M.; Kusters, J.G.

    2013-01-01

    Brachyspira species have been implicated as a potential cause of gastroenteritis in humans; this is, however, controversial. In 733 gastroenteritis cases and 464 controls, we found 29 samples positive for Brachyspira species (2.3% of cases and 2.6% of controls; P = 0.77). Brachyspira species were no

  10. Brachyspira Species and Gastroenteritis in Humans

    NARCIS (Netherlands)

    Westerman, L.J.; Boer, de R.F.; Roelfsema, J.H.; Friesema, I.H.M.; Kortbeek, L.M.; Wagenaar, J.A.; Bonten, M.J.M.; Kusters, J.G.

    2013-01-01

    Brachyspira species have been implicated as a potential cause of gastroenteritis in humans; this is, however, controversial. In 733 gastroenteritis cases and 464 controls, we found 29 samples positive for Brachyspira species (2.3% of cases and 2.6% of controls; P = 0.77). Brachyspira species were

  11. The Gilbertiodendron ogoouense species complex (Leguminosae

    NARCIS (Netherlands)

    Burgt, van der X.M.; Mackinder, B.A.; Wieringa, J.J.; Estrella, de la Manuel

    2015-01-01

    The Gilbertiodendron ogoouense species complex consists of 14 tree species. Eight species are here newly described and one is here reinstated: G. bambolense Burgt; G. breteleri Burgt; G. ebo Burgt & Mackinder; G. ecoukense (Pellegr.) Burgt; G. maximum Burgt & Wieringa; G. minkebense Burgt

  12. Endangered Species & Biodiversity: A Classroom Project & Theme

    Science.gov (United States)

    Lauro, Brook

    2012-01-01

    Students discover the factors contributing to species losses worldwide by conducting a project about endangered species as a component of a larger classroom theme of biodiversity. Groups conduct research using online endangered- species databases and present results to the class using PowerPoint. Students will improve computer research abilities…

  13. Endangered Species & Biodiversity: A Classroom Project & Theme

    Science.gov (United States)

    Lauro, Brook

    2012-01-01

    Students discover the factors contributing to species losses worldwide by conducting a project about endangered species as a component of a larger classroom theme of biodiversity. Groups conduct research using online endangered- species databases and present results to the class using PowerPoint. Students will improve computer research abilities…

  14. 75 FR 69698 - Invasive Species Advisory Committee

    Science.gov (United States)

    2010-11-15

    ... Doc No: 2010-28653] DEPARTMENT OF THE INTERIOR Office of the Secretary Invasive Species Advisory..., notice is hereby given of meetings of the Invasive Species Advisory Committee (ISAC). Comprised of 30 nonfederal invasive species experts and stakeholders from across the nation, the purpose of the Advisory...

  15. 77 FR 23740 - Invasive Species Advisory Committee

    Science.gov (United States)

    2012-04-20

    ... Office of the Secretary Invasive Species Advisory Committee AGENCY: Office of the Secretary, Interior. ACTION: Notice of Public Meetings of the Invasive Species Advisory Committee. SUMMARY: Pursuant to the provisions of the Federal Advisory Committee Act, notice is hereby given of meetings of the Invasive Species...

  16. 76 FR 68776 - Invasive Species Advisory Committee

    Science.gov (United States)

    2011-11-07

    ...] [FR Doc No: 2011-28743] DEPARTMENT OF THE INTERIOR Office of the Secretary Invasive Species Advisory..., notice is hereby given of meetings of the Invasive Species Advisory Committee (ISAC). Comprised of 29 nonfederal invasive species experts and stakeholders from across the nation, the purpose of the Advisory...

  17. Invasive Species Science Update (No. 9)

    Science.gov (United States)

    Justin Runyon

    2017-01-01

    This newsletter is designed to keep managers and other users up-to-date with recently completed and ongoing research by RMRS scientists, as well as to highlight breaking news related to invasive species issues. The newsletter is produced by the RMRS Invasive Species Working Group (ISWG), a core group of scientists who volunteer to disseminate RMRS invasive species...

  18. 77 FR 40375 - Receipt of Applications for Endangered Species Permits

    Science.gov (United States)

    2012-07-09

    ... species, 14 fish species, 34 fresh-water mussel species, 2 snail species, 1 insect species, and 2 plant... Ecology Center, Gainesville, Florida Applicant requests authorization to conduct scientific research on...

  19. Ecological impacts of non-native species

    Science.gov (United States)

    Wilkinson, John W.

    2012-01-01

    Non-native species are considered one of the greatest threats to freshwater biodiversity worldwide (Drake et al. 1989; Allen and Flecker 1993; Dudgeon et al. 2005). Some of the first hypotheses proposed to explain global patterns of amphibian declines included the effects of non-native species (Barinaga 1990; Blaustein and Wake 1990; Wake and Morowitz 1991). Evidence for the impact of non-native species on amphibians stems (1) from correlative research that relates the distribution or abundance of a species to that of a putative non-native species, and (2) from experimental tests of the effects of a non-native species on survival, growth, development or behaviour of a target species (Kats and Ferrer 2003). Over the past two decades, research on the effects of non-native species on amphibians has mostly focused on introduced aquatic predators, particularly fish. Recent research has shifted to more complex ecological relationships such as influences of sub-lethal stressors (e.g. contaminants) on the effects of non-native species (Linder et al. 2003; Sih et al. 2004), non-native species as vectors of disease (Daszak et al. 2004; Garner et al. 2006), hybridization between non-natives and native congeners (Riley et al. 2003; Storfer et al. 2004), and the alteration of food-webs by non-native species (Nystrom et al. 2001). Other research has examined the interaction of non-native species in terms of facilitation (i.e. one non-native enabling another to become established or spread) or the synergistic effects of multiple non-native species on native amphibians, the so-called invasional meltdown hypothesis (Simerloff and Von Holle 1999). Although there is evidence that some non-native species may interact (Ricciardi 2001), there has yet to be convincing evidence that such interactions have led to an accelerated increase in the number of non-native species and cumulative impacts are still uncertain (Simberloff 2006). Applied research on the control, eradication, and

  20. Novel gaseous transient species: generation and characterization

    Institute of Scientific and Technical Information of China (English)

    ZENG XiaoQing; WANG DianXun

    2007-01-01

    Due to special properties of transient species, such as short-lived, unstable, reactive, and even explosive, the generation and subsequent characterization is a great challenge for experimental chemists. In our laboratory, systematic researches have been carried out to investigate novel transient species:reactive halogen species (RHS), short-lived free radicals, and metastable pseudohalogen compounds,based on the successive technical improvements on the Hel Photoelectron spectroscopy (PES). In this review, the topic mainly focuses on innovative methods of generating novel transient species, and subsequent geometric and electronic structure characterizations of these species combined with quantum chemical calculations.

  1. Alien species on the coasts of Turkey

    Directory of Open Access Journals (Sweden)

    M.E. CINAR

    2005-12-01

    Full Text Available The compilation of data on alien species reported from the Turkish coasts yielded a total of 263 species belonging to 11 systematic groups, of which Mollusca had the highest number of species (85 species, followed by Crustacea (51, fishes (43 and phytobenthos (39. The Black Sea is represented by a total of 20 alien species, the Sea of Marmara by 48 species, the Aegean Sea by 98 species and the Levantine Sea by 202 species. The majority of aliens found in the Black Sea and the Sea of Marmara were transported via shipping, whereas the Levantine coast is extensively subjected to Lessepsian migration. Benthic habitats (soft and hard substrata comprise 76% of the total alien species and the pelagic environment is inhabited by thirty-nine species. Almost 50% of aliens collected from the Turkish coasts were found only at 0-10 m depth. Eight species occur at depths deeper than 100 m. The impacts of aliens on the benthic and pelagic ecosystems are presented.

  2. Alien species on the coasts of Turkey

    Directory of Open Access Journals (Sweden)

    M.E. CINAR

    2012-12-01

    Full Text Available The compilation of data on alien species reported from the Turkish coasts yielded a total of 263 species belonging to 11 systematic groups, of which Mollusca had the highest number of species (85 species, followed by Crustacea (51, fishes (43 and phytobenthos (39. The Black Sea is represented by a total of 20 alien species, the Sea of Marmara by 48 species, the Aegean Sea by 98 species and the Levantine Sea by 202 species. The majority of aliens found in the Black Sea and the Sea of Marmara were transported via shipping, whereas the Levantine coast is extensively subjected to Lessepsian migration. Benthic habitats (soft and hard substrata comprise 76% of the total alien species and the pelagic environment is inhabited by thirty-nine species. Almost 50% of aliens collected from the Turkish coasts were found only at 0-10 m depth. Eight species occur at depths deeper than 100 m. The impacts of aliens on the benthic and pelagic ecosystems are presented.

  3. Microbial species delineation using whole genome sequences

    Energy Technology Data Exchange (ETDEWEB)

    Kyrpides, Nikos; Mukherjee, Supratim; Ivanova, Natalia; Mavrommatics, Kostas; Pati, Amrita; Konstantinidis, Konstantinos

    2014-10-20

    Species assignments in prokaryotes use a manual, poly-phasic approach utilizing both phenotypic traits and sequence information of phylogenetic marker genes. With thousands of genomes being sequenced every year, an automated, uniform and scalable approach exploiting the rich genomic information in whole genome sequences is desired, at least for the initial assignment of species to an organism. We have evaluated pairwise genome-wide Average Nucleotide Identity (gANI) values and alignment fractions (AFs) for nearly 13,000 genomes using our fast implementation of the computation, identifying robust and widely applicable hard cut-offs for species assignments based on AF and gANI. Using these cutoffs, we generated stable species-level clusters of organisms, which enabled the identification of several species mis-assignments and facilitated the assignment of species for organisms without species definitions.

  4. Cyanogenesis in Lotus and Trifolium species

    Directory of Open Access Journals (Sweden)

    Halina Blaim

    2015-06-01

    Full Text Available The occurrence of cyanogenic plants was determined in 48 Trifolium species, 12 Lotus species, in wild population as well as in varieties of T. repens L. and Loins corniculatus L. species. In the genus Trifolium only T. nigrescens Viv. proved to be high-cyanogenic, all the remaining species are acyanogenic or low-cyanogenic. In the T. repens species varieties and wild populations include an insignificant per cent of cyanogenic plants.The genus Lotus comprises both high-cyanogenic and acyanogenic species. In the L. corniculatus species varieties include much more high-cyanogenic plants than do wild populations. It seems that in L. corniculatus the breeding went in a wrong direction, because of lack of plant selection regarding the presence of toxic compounds.

  5. Genomic definition of species. Revision 1

    Energy Technology Data Exchange (ETDEWEB)

    Crkvenjakov, R.; Dramanac, R.

    1992-06-01

    A genome is the sum total of the DNA sequences in the cells of an individual organism. The common usage that species possess genomes comes naturally to biochemists, who have shown that all protein and nucleic acid molecules are at the same time species and individual-specific, with minor individual variations being superimposed on a consensus sequence that is constant for a species. By extension, this property is attributed to the common features of DNA in the chromosomes of members of a given species and is called (species) genome. The definition of species based on chromosomes, genes, or genome common to its member organisms has been implied or mentioned in passing numerous times. Some population biologists think that members of species have similar ``homeostatic genotypes,`` which are to a degree resistant to mutation or environmental change in the production of a basic phenotype.

  6. Petal anatomy of four Justicia (Acanthaceae) species

    Science.gov (United States)

    Amirul-Aiman, A. J.; Noraini, T.; Nurul-Aini, C. A. C.; Ruzi, A. R.

    2013-11-01

    Comparative anatomical study on flower petals was studied in four selected Justicia species from Peninsular Malaysia, i.e. J. comata (L.) Lam., J. carnea Lindl. J. betonica Linn. and J. procumbens L with the objective to provide useful data for species identification and differentiation within the genus of Justicia. Methods used in this study are mechanical scrapping on the leaf surfaces and observation under light microscope. Finding in this study has shown that all species are sharing similar type of anticlinal walls pattern, which is sinuous pattern. Two or more type of trichomes is present in all species studied and this character can be used to differentiate Justicia species. Simple multicellular trichomes are found to be present in all species studied. Justicia betonica can be isolated from other species by the existence of cyclo-paracytic stomata on the petal surfaces.

  7. Genomic definition of species. Revision 2

    Energy Technology Data Exchange (ETDEWEB)

    Crkvenjakov, R.; Drmanac, R.

    1993-03-01

    A genome is the sum total of the DNA sequences in the cells of an individual organism. The common usage that species possess genomes comes naturally to biochemists, who have shown that all protein and nucleic acid molecules are at the same time species- and individual-specific, with minor individual variations being superimposed on a consensus sequence that is constant for a species. By extension, this property is attributed to the common features of DNA in the chromosomes of members of a given species and is called species genome. Our proposal for the definition of a biological species is as follows: A species comprises a group of actual and potential biological organisms built according to a unique genome program that is recorded, and at least in part expressed, in the structures of their genomic nucleic acid molecule(s), having intragroup sequence differences which can be fully interconverted in the process of organismal reproduction.

  8. Species concepts and biodiversity in Trichoderma and Hypocrea: from aggregate species to species clusters?

    Institute of Scientific and Technical Information of China (English)

    DRUZHININA Irina; KUBICEK Christian P.

    2005-01-01

    Trichoderma/Hypocrea is a genus of soil-borne or wood-decaying fungi containing members important to mankind as producers of industrial enzymes and biocontrol agents against plant pathogens, but also as opportunistic pathogens of immunocompromised humans. Species identification, while essential in view of the controversial properties of taxa ofthis genus, has been problematic by traditional methods. Here we will present a critical survey of the various identification methods in use. In addition,we will present an update on the taxonomy and phylogeny of the 88 taxa (which occur as 14 holomorphs, 49 teleomorphs and 25 anamorphs in nature) of Trichoderma/Hypocrea that have been confirmed by a combination of morphological, physiological and genetic approaches.

  9. Plant responses to climatic extremes: within-species variation equals among-species variation

    DEFF Research Database (Denmark)

    Malyshev, Andrey; Arfin Kahn, Mohammed A.S.; Beierkuhnlein, Carl

    2016-01-01

    , root 15N uptake, and live and dead tissue mass. Using coefficients of variation (CVs) for each experiment and response parameter, a total of 156 within- vs. among-species comparisons were conducted, comparing within-species variation in each of four species with among- species variation for each seed......) and for practical applications (e.g., biodiversity conservation)....

  10. Effects of tree species composition on within-forest distribution of understorey species

    NARCIS (Netherlands)

    Oijen, van D.; Feijen, M.; Hommel, P.W.F.M.; Ouden, den J.; Waal, de R.W.

    2005-01-01

    Question: Do tree species, with different litter qualities, affect the within-forest distribution of forest understorey species on intermediate to base-rich soils? Since habitat loss and fragmentation have caused ancient forest species to decline, those species are the main focus of this study. Loca

  11. Program SimAssem: software for simulating species assemblages and estimating species richness

    Science.gov (United States)

    Gordon C. Reese; Kenneth R. Wilson; Curtis H. Flather

    2013-01-01

    1. Species richness, the number of species in a defined area, is the most frequently used biodiversity measure. Despite its intuitive appeal and conceptual simplicity, species richness is often difficult to quantify, even in well surveyed areas, because of sampling limitations such as survey effort and species detection probability....

  12. Four new species of Pteromalus Swederus (Hymenoptera: Chalcidoidea: Pteromalidae) and redescriptions of three other species

    NARCIS (Netherlands)

    Gijswijt, M.J.

    1999-01-01

    A key to the European species of the Pteromalus altus group is presented. The relationship between this group and species of the genus Euphorbia (Euphorbiaceae) is confirmed. One new species: P. villosae, associated with Euphorbia villosa Waldst. & Kit.is presented. Two new species of the albipennis

  13. Ribonuclease Production by Aspergillus species

    Directory of Open Access Journals (Sweden)

    Gomes Eleni

    1998-01-01

    Full Text Available Ribonuclease production by Aspergillus flavipes, A. sulphureus and A. fischeri in semi-synthetic medium, after 24-144 hours at 30ºC under shaking, was studied. After cultivation, the medium was separated from micelia by filtration and the resultant solution was used as enzymatic extract. The highest amount of biomass and RNase was obtained after 96 hours of cultivation. The enzymes produced by three species presented similar characteristics, with optimum temperature at 55ºC and two peaks of activity at pH 4.5 and 7.0. A. flavipes RNases were more sensitive to temperature: 50% of the initial activity was lost after 1 hour at 70ºC. After this heat treatment, RNase of A. sulphureus lost 30% of this activity and that of A. fischeri only 16%. The nucleotides released by enzimatic hydrolysis of RNA were separated by ion exchange chromatography in a AG-1X8-formiate column and identified by paper chromatography. This procedure indicated that the raw enzymatic extract of Aspergillus flavipes is able to hydrolyze RNA, releasing 3'-nucleotides monophosphate at pH 4.5 and 3' and 5'-nucleotides monophosphate at pH 7.0 and 8.5. This result suggests that this strain produces two different types of RNase, one acidic and other alcaline, with different specificities.

  14. Secondary Metabolites from Rubiaceae Species

    Directory of Open Access Journals (Sweden)

    Daiane Martins

    2015-07-01

    Full Text Available This study describes some characteristics of the Rubiaceae family pertaining to the occurrence and distribution of secondary metabolites in the main genera of this family. It reports the review of phytochemical studies addressing all species of Rubiaceae, published between 1990 and 2014. Iridoids, anthraquinones, triterpenes, indole alkaloids as well as other varying alkaloid subclasses, have shown to be the most common. These compounds have been mostly isolated from the genera Uncaria, Psychotria, Hedyotis, Ophiorrhiza and Morinda. The occurrence and distribution of iridoids, alkaloids and anthraquinones point out their chemotaxonomic correlation among tribes and subfamilies. From an evolutionary point of view, Rubioideae is the most ancient subfamily, followed by Ixoroideae and finally Cinchonoideae. The chemical biosynthetic pathway, which is not so specific in Rubioideae, can explain this and large amounts of both iridoids and indole alkaloids are produced. In Ixoroideae, the most active biosysthetic pathway is the one that produces iridoids; while in Cinchonoideae, it produces indole alkaloids together with other alkaloids. The chemical biosynthetic pathway now supports this botanical conclusion.

  15. Species longevity in North American fossil mammals.

    Science.gov (United States)

    Prothero, Donald R

    2014-08-01

    Species longevity in the fossil record is related to many paleoecological variables and is important to macroevolutionary studies, yet there are very few reliable data on average species durations in Cenozoic fossil mammals. Many of the online databases (such as the Paleobiology Database) use only genera of North American Cenozoic mammals and there are severe problems because key groups (e.g. camels, oreodonts, pronghorns and proboscideans) have no reliable updated taxonomy, with many invalid genera and species and/or many undescribed genera and species. Most of the published datasets yield species duration estimates of approximately 2.3-4.3 Myr for larger mammals, with small mammals tending to have shorter species durations. My own compilation of all the valid species durations in families with updated taxonomy (39 families, containing 431 genera and 998 species, averaging 2.3 species per genus) yields a mean duration of 3.21 Myr for larger mammals. This breaks down to 4.10-4.39 Myr for artiodactyls, 3.14-3.31 Myr for perissodactyls and 2.63-2.95 Myr for carnivorous mammals (carnivorans plus creodonts). These averages are based on a much larger, more robust dataset than most previous estimates, so they should be more reliable for any studies that need species longevity to be accurately estimated. © 2013 International Society of Zoological Sciences, Institute of Zoology/Chinese Academy of Sciences and Wiley Publishing Asia Pty Ltd.

  16. A Theory of Flagship Species Action

    Directory of Open Access Journals (Sweden)

    Paul Jepson

    2015-01-01

    Full Text Available The flagship species approach is an enduring strategy in conservation. Academic discussion on flagship species has focussed on two dimensions: on what basis should they be selected and how have they been put to use. Here we consider a third dimension, namely the manner in which flagship species act and have the capacity to galvanise and influence conservation outcomes. Drawing on concepts from the social sciences, viz. affordance, framing, and actor-networks; we discuss examples of flagship species to propose a theory of flagship species action. In brief, our theory posits that a flagship species is one with traits that afford the assembly of relatively coherent networks of associations with ideational elements located in pre-existing cultural framings. These associations give rise to opportunities to align with deep cultural frames, contemporary cultural phenomena and political economy such that when a conservation action is introduced, forms of agency cause the species and human publics to change. The species becomes re-framed (or reinvigorated as a cultural asset speaking for a wider nature, publics and political agendas. Further our theory posits that species with traits that enrol in idea networks incorporating human fears, will have limited flagship capacity. This is because the ability of the representations produced to align with frames incorporating collective aspirations is constrained. In terms of applied conservation practice, our theory suggests that: a key criteria for selecting potential flagship species is presence in existing cultural frames, that effective deployment of flagship species requires an understanding of the species′ cultural associations, and a species ability to galvanise action may be limited to certain times and places. Furthermore, once deployed conservation interests will never have full control over the flagship species: it may act in uncertain and unexpected ways.

  17. Species of Timber Shade Trees

    Directory of Open Access Journals (Sweden)

    Adi Prawoto

    2008-05-01

    Full Text Available Cocoa (Theobroma cacao L. like most tropical trees is recalcitrant in tissue culture. Somatic embryogenesis is generally efficient micropropagation technique to multiply elite material. However, Somatic embryogenesis in cocoa is difficult and this species is considered as recalcitrant. One of the factors often considered as a component of in vitro recalsitrance is a high phenolic content and oxidation of these compounds. In cocoa tissue culture accumulate large amounts of poliphenolics compounds which probably impair further development. This study was conducted to investigate the composition of phenolic compounds in cocoa flower and leaves, and their changes troughout the somatic embryogenesis process. Calli were induced in cacao floral and leaves explants on a half-strenght Murashige and Skoog medium containing 30 g/L Glucose and combination of 2,4 dichlorophenoxyacetic acid (2,4 D with kinetin (kin. Total polyphenol content was observed on Sulawesi 1 cocoa clone. Embryogenic and non-embryogenic callus were also compared. The percentage of callus production from flower tissue is 85%, percentage of embryogenic callus 40 %, although  the percentage of somatic embryo production from embryogenic callus callus is 70%. The conservation of callus into somatic embryos followed by decline in phenol content and an increase in peroxidase. The synthesis kinetics for these compounds in calli, under different somatic embryogenesis conditions, revealed a higher concentration under non-embryogenic conditions. So that, phenolic compound can influence the production of calli and an absence the phenolic compound can enhance production of somatic embryo.Kata kunci: Theobroma cacao L., polifenol, embrio somatik, kalus, flavonoid, katekin, in vitro recalcitance

  18. Artificial Induction of Gynogenetic Diploids in Blue Mussel Mytilus Galloprovincialis%紫贻贝雌核发育二倍体的人工诱导研究

    Institute of Scientific and Technical Information of China (English)

    齐明君; 李琪; 孔令锋; 于红

    2014-01-01

    采用紫外线照射的方式使精子遗传物质失活,通过细胞松弛素B(CB)的处理来抑制受精卵第二极体的释放,人工诱导紫贻贝(Mytilus galloprovincialis)雌核发育二倍体.将精子在强度为2561uW/ (cm2·s)的紫外线(254 nm)下进行时间梯度的照射,之后与正常的卵子受精,实验发现随照射时间的增加,卵裂率、早期胚胎存活率和D形幼虫发生率总体呈下降趋势,在照射55s时D形幼虫发生率降为0.受精后25 min,用浓度0.5μg/ mL的细胞松弛素B(CB)持续处理受精卵20 min,诱导出紫贻贝第二极体抑制型雌核发育二倍体.通过微卫星分析鉴定所得的子代个体均为雌核发育二倍体.

  19. Aging and immortality in unicellular species.

    Science.gov (United States)

    Florea, Michael

    2017-08-24

    It has been historically thought that in conditions that permit growth, most unicellular species do not to age. This was particularly thought to be the case for symmetrically dividing species, as such species lack a clear distinction between the soma and the germline. Despite this, studies of the symmetrically dividing species Escherichia coli and Schizosaccharomyces pombe have recently started to challenge this notion. They indicate that E. coli and S. pombe do age, but only when subjected to environmental stress. If true, this suggests that aging may be widespread among microbial species in general, and that studying aging in microbes may inform other long-standing questions in aging. This review examines the recent evidence for and against replicative aging in symmetrically dividing unicellular organisms, the mechanisms that underlie aging, why aging evolved in these species, and how microbial aging fits into the context of other questions in aging. Copyright © 2017 Elsevier B.V. All rights reserved.

  20. Diversity of invasive species in Shanghai

    Directory of Open Access Journals (Sweden)

    Qingrou Zhang

    2013-11-01

    Full Text Available A list of invasive alien species (IAS is essential for initiating an analysis of the biological and ecological traits of such species and for improving our understanding of patterns of biological invasions. An inventory of IAS in Shanghai was prepared through a literature survey. A total of 212 IAS belonging to 63 orders and 87 families were recorded. Of these, 65% were plants, 29% were animals, and the rest were microorganisms. Dominant groups could be distinguished in both plant and animal groups. Species originating from the Americas made up 51% of the total, while 52% of plant species were introduced intentionally and 82% of animal species unintentionally. Of the invasive plants, 93% are distributed in highly disturbed habitats with rich resources, whereas 76% of invasive animals occur in storehouses and farmlands. The present information on diversity and ecological features of IAS is crucial for designing management strategies against the negative impacts of such species in Shanghai.

  1. The Species Problem in Myxomycetes Revisited.

    Science.gov (United States)

    Walker, Laura M; Stephenson, Steven L

    2016-08-01

    Species identification in the myxomycetes (plasmodial slime molds or myxogastrids) poses particular challenges to researchers as a result of their morphological plasticity and frequent alteration between sexual and asexual life strategies. Traditionally, myxomycete morphology has been used as the primary method of species delimitation. However, with the increasing availability of genetic information, traditional myxomycete taxonomy is being increasingly challenged, and new hypotheses continue to emerge. Due to conflicts that sometimes occur between traditional and more modern species concepts that are based largely on molecular data, there is a pressing need to revisit the discussion surrounding the species concept used for myxomycetes. Biological diversity is being increasingly studied with molecular methods and data accumulates at ever-faster rates, making resolution of this matter urgent. In this review, currently used and potentially useful species concepts (biological, morphological, phylogenetic and ecological) are reviewed, and an integrated approach to resolve the myxomycete species problem is discussed. Copyright © 2016 Elsevier GmbH. All rights reserved.

  2. Plant species in the kilimanjaro agroforestry system

    Energy Technology Data Exchange (ETDEWEB)

    O' kting' ati, A.; Maghembe, J.A.; Fernandes, E.C.M.; Weaver, G.H.

    1984-01-01

    An inventory of plant species was conducted on 30 farms, farm boundaries and homesteads in 6 villages in Hai District on the slopes of Mt. Kilimanjaro, Tanzania. Of 111 plant species identified, 53 were tree species, 29 food crop species, 21 non-woody plants of economic value and 8 weed species. Information on uses was obtained through interviews with farmers. Useful plants (most with 2 or more uses) were carefully chosen and closely intercropped on the same unit of land. Of the tree species, 90% were used for fuelwood, 30% for medicines, 25% for poles, 24% for shade, 23% for timber and 10% for fodder. These, and food, were the most important plant uses.

  3. Self-localized states in species competition

    Science.gov (United States)

    Paulau, Pavel V.; Gomila, DamiÃ; López, Cristóbal; Hernández-García, Emilio

    2014-03-01

    We study the conditions under which species interaction, as described by continuous versions of the competitive Lotka-Volterra model (namely the nonlocal Kolmogorov-Fisher model, and its differential approximation), can support the existence of localized states, i.e., patches of species with enhanced population surrounded in niche space by species at smaller densities. These states would arise from species interaction, and not by any preferred niche location or better fitness. In contrast to previous works we include only quadratic nonlinearities, so that the localized patches appear on a background of homogeneously distributed species coexistence, instead of on top of the no-species empty state. For the differential model we find and describe in detail the stable localized states. For the full nonlocal model, however, competitive interactions alone do not allow the conditions for the observation of self-localized states, and we show how the inclusion of additional facilitative interactions leads to the appearance of them.

  4. Fisheries oceanography of northern pelagic fish species

    DEFF Research Database (Denmark)

    Tsoukali, Stavroula

    of the species they consume now and increased availability of new species. In addition, there will likely be economic impacts on the local fishing communities. How species respond to climate change is a field of research that receives great attention because the responses will affect the management of fisheries...... range that maximizes survival among different species, but the sensitivity of egg development rate in a degree of temperature increase is similar among the 32 species and populations I analysed. I also found that adults spawn at temperature conditions that are generally close to the egg preferences...... seasons, at lower latitudes, are able to produce 10 times more eggs during their life time than species than have a limited spawning season. This may reflect the more un-predictable environmental conditions at lower latitudes. People are also familiar with the words "climate change" and "warming...

  5. Reactive Oxygen Species in Skeletal Muscle Signaling

    OpenAIRE

    2012-01-01

    Generation of reactive oxygen species (ROS) is a ubiquitous phenomenon in eukaryotic cells' life. Up to the 1990s of the past century, ROS have been solely considered as toxic species resulting in oxidative stress, pathogenesis and aging. However, there is now clear evidence that ROS are not merely toxic species but also—within certain concentrations—useful signaling molecules regulating physiological processes. During intense skeletal muscle contractile activity myotubes' mitochondria genera...

  6. Wildlife Trade and Endangered Species Protection

    OpenAIRE

    Paul Missios

    2013-01-01

    Markets for endangered species potentially generate incentives for both legal supply and poaching. To deter poaching, governments can spend on enforcement or increase legal harvesting to reduce the return from poaching. A leader–follower commitment game is developed to examine these choices in the presence of illegal harvesting and the resulting impacts on species stocks. In addition, current trade restrictions imposed under the Convention on International Trade in Endangered Species of Wild ...

  7. Sensory quality criteria for five fish species

    DEFF Research Database (Denmark)

    Warm, Karin; Nielsen, Jette; Hyldig, Grethe;

    2000-01-01

    Sensory profiling has been used to develop one sensory vocabulary for five fish species: cod (Gadus morhua), saithe (Pollachius virens), rainbow trout (Salmo gardineri), herring (Clupea harengus) and flounder (Platichthys flessus). A nine- member trained panel assessed 18 samples with variation...... variation and by presenting references, panel discussions and interpreting plots from multivariate data analysis. The developed profile can be used as a sensory wheel for these species, and with minor changes it may be adapted to similar species...

  8. Species discrimination from a hyperspectral perspective

    OpenAIRE

    Sobhan, I.

    2007-01-01

    Sustainable management of natural ecosystems requires comprehensive information on species distribution and composition. Remote sensing has the potential to improve the collection of information on species composition. Compared to other vegetation attributes plant species so far remained a difficult attribute to detect with remote sensing. Broad band remote sensing sensors, which have been used extensively for mapping of plant communities, are however not sufficiently sensitive to allow discr...

  9. Species - San Diego Co. [ds121

    Data.gov (United States)

    California Department of Resources — This is the Biological Observation Database point layer representing baseline observations of sensitive species (as defined by the MSCP) throughout San Diego County....

  10. Cytotoxic constituents of Alectra and Striga species

    DEFF Research Database (Denmark)

    Rank, Christian; Rasmussen, Lars S.; Jensen, Søren Rosendal

    2004-01-01

    Decimation of cereal growth and yields by hemiparasitic Striga species cannot be accounted for entirely by the removal of host-plant resources. The production of toxic compounds by the parasite has been suggested. An investigation of three species of the economically important Striga and the rela......Decimation of cereal growth and yields by hemiparasitic Striga species cannot be accounted for entirely by the removal of host-plant resources. The production of toxic compounds by the parasite has been suggested. An investigation of three species of the economically important Striga...

  11. Cocaine distribution in wild Erythroxylum species.

    Science.gov (United States)

    Bieri, Stefan; Brachet, Anne; Veuthey, Jean-Luc; Christen, Philippe

    2006-02-20

    Cocaine distribution was studied in leaves of wild Erythroxylum species originating from Bolivia, Brazil, Ecuador, Paraguay, Peru, Mexico, USA, Venezuela and Mauritius. Among 51 species, 28 had never been phytochemically investigated before. Cocaine was efficiently and rapidly extracted with methanol, using focused microwaves at atmospheric pressure, and analysed without any further purification by capillary gas chromatography coupled to mass spectrometry. Cocaine was reported for the first time in 14 species. Erythroxylum laetevirens was the wild species with the highest cocaine content. Its qualitative chromatographic profile also revealed other characteristic tropane alkaloids. Finally, its cocaine content was compared to those of two cultivated coca plants as well as with a coca tea bag sample.

  12. Species coexistence in a lattice-structured habitat: effects of species dispersal and interactions.

    Science.gov (United States)

    Ying, Zhixia; Liao, Jinbao; Wang, Shichang; Lu, Hui; Liu, Yongjie; Ma, Liang; Li, Zhenqing

    2014-10-21

    Opinions differ on how the spatial distribution of species over space affects species coexistence. Here, we constructed both mean-field and pair approximation (PA) models to explore the effects of interspecific and intraspecific interactions and dispersal modes on species coexistence. We found that spatial structure resulting from species dispersal traits and neighboring interactions in PA model did not promote coexistence if two species had the same traits, though it might intensify the contact frequency of intraspecific competition. If two species adopt different dispersal modes, the spatial structure in PA would make the coexistence or founder control less likely since it alters the species effective birth rate. This suggests that the spatial distribution caused by neighboring interactions and local dispersal does not affect species coexistence unless it adequately alters the effective birth rate for two species. Besides, we modeled how the initial densities and patterns affected population dynamics and revealed how the final spatial pattern was generated.

  13. Development and Evaluation of Species-Specific PCR for Detection of Nine Acinetobacter Species.

    Science.gov (United States)

    Li, Xue Min; Choi, Ji Ae; Choi, In Sun; Kook, Joong Ki; Chang, Young-Hyo; Park, Geon; Jang, Sook Jin; Kang, Seong Ho; Moon, Dae Soo

    2016-05-01

    Molecular methods have the potential to improve the speed and accuracy of Acinetobacter species identification in clinical settings. The goal of this study is to develop species-specific PCR assays based on differences in the RNA polymerase beta-subunit gene (rpoB) to detect nine commonly isolated Acinetobacter species including Acinetobacter baumannii, Acinetobacter calcoaceticus, Acinetobacter pittii, Acinetobacter nosocomialis, Acinetobacter lwoffii, Acinetobacter ursingii, Acinetobacter bereziniae, Acinetobacter haemolyticus, and Acinetobacter schindleri. The sensitivity and specificity of these nine assays were measured using genomic DNA templates from 55 reference strains and from 474 Acinetobacter clinical isolates. The sensitivity of A. baumannii-specific PCR assay was 98.9%, and the sensitivity of species-specific PCR assays for all other species was 100%. The specificities of A. lwoffii- and A. schindleri-specific PCR were 97.8 and 98.9%, respectively. The specificity of species-specific PCR for all other tested Acinetobacter species was 100%. The lower limit of detection for the nine species-specific PCR assays developed in this study was 20 or 200 pg of genomic DNA from type strains of each species. The Acinetobacter species-specific PCR assay would be useful to determine the correct species among suggested candidate Acinetobacter species when conventional methods including MALDI-TOF MS identify Acinetobacter only to the genus level. The species-specific assay can be used to screen large numbers of clinical and environmental samples obtained for epidemiologic study of Acinetobacter for the presence of target species.

  14. Species-specific associations between overstory and understory tree species in a semideciduous tropical forest

    Directory of Open Access Journals (Sweden)

    Flaviana Maluf Souza

    2015-03-01

    Full Text Available We investigated the occurrence of associations between overstory and understory tree species in a semideciduous tropical forest. We identified and measured all trees of nine canopy species with diameter at breast height ≥4.8 cm in a 10.24 ha plot and recorded all individuals beneath their canopies ("understory individuals" within the same diameter class. The total density of understory individuals did not significantly differ under different overstory species. One overstory species (Ceiba speciosa showed higher understory species richness compared with five other species. There was a strong positive association between three overstory species (Esenbeckia leiocarpa, Savia dictyocarpa, and C. speciosa and the density of seven understory species (Balfourodendron riedelianum, Chrysophyllum gonocarpum, E. leiocarpa, Holocalyx balansae, Machaerium stipitatum, Rhaminidium elaeocarpum, and S. dictyocarpa. These results probably reflect the outcome of a complex set of interactions including facilitation and competition, and further studies are necessary to better understand the magnitude and type of the effects of individual overstory species on understory species. The occurrence of species-specific associations shown here reinforces the importance of non-random processes in structuring plant communities and suggest that the influence of overstory species on understory species in high-diversity forests may be more significant than previously thought.

  15. Selecting focal species as surrogates for imperiled species using relative sensitivities derived from occupancy analysis

    Science.gov (United States)

    Silvano, Amy; Guyer, Craig; Steury, Todd; Grand, James B.

    2017-01-01

    Most imperiled species are rare or elusive and difficult to detect, which makes gathering data to estimate their response to habitat restoration a challenge. We used a repeatable, systematic method for selecting focal species using relative sensitivities derived from occupancy analysis. Our objective was to select suites of focal species that would be useful as surrogates when predicting effects of restoration of habitat characteristics preferred by imperiled species. We developed 27 habitat profiles that represent general habitat relationships for 118 imperiled species. We identified 23 regularly encountered species that were sensitive to important aspects of those profiles. We validated our approach by examining the correlation between estimated probabilities of occupancy for species of concern and focal species selected using our method. Occupancy rates of focal species were more related to occupancy rates of imperiled species when they were sensitive to more of the parameters appearing in profiles of imperiled species. We suggest that this approach can be an effective means of predicting responses by imperiled species to proposed management actions. However, adequate monitoring will be required to determine the effectiveness of using focal species to guide management actions.

  16. Endangered Species: Real Life in Two Dimensions

    Science.gov (United States)

    Henderson, Lynette K.

    2012-01-01

    The focus of "Endangered Species: Real Life in Two Dimensions" is to create awareness about a critical environmental issue. There is a special urgency to this project because large numbers of animal species are currently endangered or on the brink of extinction. In addition to being enlightened about this important topic through research, students…

  17. Lichtheimia species exhibit differences in virulence potential.

    Directory of Open Access Journals (Sweden)

    Volker U Schwartze

    Full Text Available Although the number of mucormycosis cases has increased during the last decades, little is known about the pathogenic potential of most mucoralean fungi. Lichtheimia species represent the second and third most common cause of mucormycosis in Europe and worldwide, respectively. To date only three of the five species of the genus have been found to be involved in mucormycosis, namely L. corymbifera, L. ramosa and L. ornata. However, it is not clear whether the clinical situation reflects differences in virulence between the species of Lichtheimia or whether other factors are responsible. In this study the virulence of 46 strains of all five species of Lichtheimia was investigated in chicken embryos. Additionally, strains of the closest-related genus Dichotomocladium were tested. Full virulence was restricted to the clinically relevant species while all strains of L. hyalospora, L. sphaerocystis and Dichotomocladium species were attenuated. Although virulence differences were present in the clinically relevant species, no connection between origin (environmental vs clinical or phylogenetic position within the species was observed. Physiological studies revealed no clear connection of stress resistance and carbon source utilization with the virulence of the strains. Slower growth at 37°C might explain low virulence of L. hyalospora, L. spaherocystis and Dichotomocladium; however, similarly slow growing strains of L. ornata were fully virulent. Thus, additional factors or a complex interplay of factors determines the virulence of strains. Our data suggest that the clinical situation in fact reflects different virulence potentials in the Lichtheimiaceae.

  18. The Invasive Plant Species Education Guide

    Science.gov (United States)

    Mason, Kevin; James, Krista; Carlson, Kitrina; D'Angelo, Jean

    2010-01-01

    To help high school students gain a solid understanding of invasive plant species, university faculty and students from the University of Wisconsin-Stout (UW-Stout) and a local high school teacher worked together to develop the Invasive Plant Species (IPS) Education Guide. The IPS Education Guide includes nine lessons that give students an…

  19. Multiplexed microsatellite markers for seven Metarhizium species

    Science.gov (United States)

    Cross-species transferability of 41 previously published simple sequence repeat (SSR) markers was assessed for 11 species of the entomopathogenic fungus Metarhizium. A collection of 65 Metarhizium isolates including all 54 used in a recent phylogenetic revision of the genus were characterized. Betwe...

  20. A new Helota-species from Sumatra

    NARCIS (Netherlands)

    Ritsema Cz., C.

    1899-01-01

    The species described in this Note and dedicated to the late Dr. E. Candèze of Glain near Liege is very interesting necessitating the establishment of a new section in my Synopsis of the species of this genus 1). It belongs to the division I (base of elytra coloured as the apex), A (elytra with four

  1. Biogeography: are tropical species less specialised?

    Science.gov (United States)

    Ollerton, Jeff

    2012-11-06

    Species richness increases from the poles to the tropics, which has led to the view that interactions in tropical species are more specialised. A new study on pollinators and seed dispersers finds that tropical interactions are in fact less specialised. Copyright © 2012 Elsevier Ltd. All rights reserved.

  2. Alkaloids of some Asian Sedum species

    NARCIS (Netherlands)

    Kim, JH; THart, H; Stevens, JF

    1996-01-01

    The leafy parts of 16 Asian species belonging to the three sections of Sedum were investigated for the presence of alkaloids. Only in seven species of Sedum sect. Sedum were alkaloids found. Sedum bulbiferum, S. japonicum, S. lepidopodium, S. morrisomensis, S. oryzifolium, S. polytrichoides and S. s

  3. Multiple bacterial species reside in chronic wounds

    DEFF Research Database (Denmark)

    Gjødsbøl, Kristine; Christensen, Jens Jørgen; Karlsmark, Tonny;

    2006-01-01

    species present were identified. More than one bacterial species were detected in all the ulcers. The most common bacteria found were Staphylococcus aureus (found in 93.5% of the ulcers), Enterococcus faecalis (71.7%), Pseudomonas aeruginosa (52.2%), coagulase-negative staphylococci (45.7%), Proteus...

  4. Species diversity of Trichoderma in Poland

    Science.gov (United States)

    Fifteen species of Trichoderma were identified from among 118 strains originating from different regions and ecological niches in Poland. This low number indicates low species diversity of Trichoderma in this Central European region. Using the ITS1-ITS2 regions, 64 strains were positively identified...

  5. Endangered Species (Plants). LC Science Tracer Bullet.

    Science.gov (United States)

    Niskern, Diana, Comp.

    This guide is intended for those who wish to study the literature dealing with various aspects of endangered plant species. This document includes the following sections, some of which are bibliographies: (1) "Introductions to the Topic"; (2) "Subject Headings" (for endangered species of plants used by the Library of Congress); (3) "General…

  6. SERI Aquatic Species Program: 1983 Annual Report

    Energy Technology Data Exchange (ETDEWEB)

    1984-03-01

    During 1983 research was carried out under three tasks: biological, engineering, and analysis. Biological research was aimed at screening for promising species of microalgae, macroalgae, and emergent plants that could be cultivated for energy products. Promising species were studied further to improve yields.

  7. Finessing atlas data for species distribution models

    NARCIS (Netherlands)

    Niamir, A.; Skidmore, A.K.; Toxopeus, A.G.; Munoz, A.R.; Real, R.

    2011-01-01

    Aim The spatial resolution of species atlases and therefore resulting model predictions are often too coarse for local applications. Collecting distribution data at a finer resolution for large numbers of species requires a comprehensive sampling effort, making it impractical and expensive. This stu

  8. Cytotoxic constituents of Alectra and Striga species

    DEFF Research Database (Denmark)

    Rank, Christian; Rasmussen, Lars S.; Jensen, Søren Rosendal

    2004-01-01

    Decimation of cereal growth and yields by hemiparasitic Striga species cannot be accounted for entirely by the removal of host-plant resources. The production of toxic compounds by the parasite has been suggested. An investigation of three species of the economically important Striga and the rela...

  9. Southern African species of Mentha L. (Lamiaceae

    Directory of Open Access Journals (Sweden)

    L. E. Codd

    1983-12-01

    Full Text Available The species of Mentha L. occurring in Southern Africa are reviewed and a key is provided to two indigenous and one naturalized species.  M. wissii Launert is reduced to M. longifolia (L. Huds. subsp. wissii (Launert Codd.

  10. Two New American Species of Hordeum (Poaceae)

    DEFF Research Database (Denmark)

    Bothmer, Roland Von; Jacobsen, Niels; Bagger Jørgensen, Rikke

    1985-01-01

    Two new species of Hordeum are described, viz. the diploid H. erectifolium, native to Argentina, and H. guatemalense, native to Guatemala.......Two new species of Hordeum are described, viz. the diploid H. erectifolium, native to Argentina, and H. guatemalense, native to Guatemala....

  11. Taxonomy of Penicillium citrinum and related species

    DEFF Research Database (Denmark)

    Houbraken, J.A.M.P.; Frisvad, Jens Christian; Samson, A.F.

    2010-01-01

    Penicillium citrinum and related species have been examined using a combination of partial beta-tubulin, calmodulin and ITS sequence data, extrolite patterns and phenotypic characters. It is concluded that seven species belong to the series Citrina. Penicillium sizovae and Penicillium steckii are...

  12. Toward reassessing data-deficient species.

    Science.gov (United States)

    Bland, Lucie M; Bielby, Jon; Kearney, Stephen; Orme, C David L; Watson, James E M; Collen, Ben

    2017-06-01

    One in 6 species (13,465 species) on the International Union for Conservation of Nature (IUCN) Red List is classified as data deficient due to lack of information on their taxonomy, population status, or impact of threats. Despite the chance that many are at high risk of extinction, data-deficient species are typically excluded from global and local conservation priorities, as well as funding schemes. The number of data-deficient species will greatly increase as the IUCN Red List becomes more inclusive of poorly known and speciose groups. A strategic approach is urgently needed to enhance the conservation value of data-deficient assessments. To develop this, we reviewed 2879 data-deficient assessments in 6 animal groups and identified 8 main justifications for assigning data-deficient status (type series, few records, old records, uncertain provenance, uncertain population status or distribution, uncertain threats, taxonomic uncertainty, and new species). Assigning a consistent set of justification tags (i.e., consistent assignment to assessment justifications) to species classified as data deficient is a simple way to achieve more strategic assessments. Such tags would clarify the causes of data deficiency; facilitate the prediction of extinction risk; facilitate comparisons of data deficiency among taxonomic groups; and help prioritize species for reassessment. With renewed efforts, it could be straightforward to prevent thousands of data-deficient species slipping unnoticed toward extinction. © 2016 Society for Conservation Biology.

  13. The Invasive Plant Species Education Guide

    Science.gov (United States)

    Mason, Kevin; James, Krista; Carlson, Kitrina; D'Angelo, Jean

    2010-01-01

    To help high school students gain a solid understanding of invasive plant species, university faculty and students from the University of Wisconsin-Stout (UW-Stout) and a local high school teacher worked together to develop the Invasive Plant Species (IPS) Education Guide. The IPS Education Guide includes nine lessons that give students an…

  14. The South African Species of Myrica

    Directory of Open Access Journals (Sweden)

    D. J. B. Killick

    1969-12-01

    Full Text Available The South African species of Myrica are revised, the 19 species previously recognized being reduced to 9. One variety is elevated to specific rank, viz. M. conifera Burm.f. var.  Integra A. Chev. becomes M. Integra (A. Chev. Killick.

  15. Rapid molecular technique to distinguish Fusarium species

    CSIR Research Space (South Africa)

    Lodolo, EJ

    1993-03-01

    Full Text Available The nuclear DNA (nDNA) of different isolates of three closely related, toxin-producing Fusarium species, F. moniliforme, F. nygamai and F. napiforme, was compared to ascertain the sensitivity of a molecular method to distinguish these three species...

  16. Finessing atlas data for species distribution models

    NARCIS (Netherlands)

    Niamir, A.; Skidmore, A.K.; Toxopeus, A.G.; Munoz, A.R.; Real, R.

    2011-01-01

    Aim The spatial resolution of species atlases and therefore resulting model predictions are often too coarse for local applications. Collecting distribution data at a finer resolution for large numbers of species requires a comprehensive sampling effort, making it impractical and expensive. This

  17. A cross-species alignment tool (CAT)

    DEFF Research Database (Denmark)

    Li, Heng; Guan, Liang; Liu, Tao;

    2007-01-01

    sensitive methods which are usually applied in aligning inter-species sequences. RESULTS: Here we present a new algorithm called CAT (for Cross-species Alignment Tool). It is designed to align mRNA sequences to mammalian-sized genomes. CAT is implemented using C scripts and is freely available on the web...

  18. Emergent neutrality drives phytoplankton species coexistence

    Science.gov (United States)

    Segura, Angel M.; Calliari, Danilo; Kruk, Carla; Conde, Daniel; Bonilla, Sylvia; Fort, Hugo

    2011-01-01

    The mechanisms that drive species coexistence and community dynamics have long puzzled ecologists. Here, we explain species coexistence, size structure and diversity patterns in a phytoplankton community using a combination of four fundamental factors: organism traits, size-based constraints, hydrology and species competition. Using a ‘microscopic’ Lotka–Volterra competition (MLVC) model (i.e. with explicit recipes to compute its parameters), we provide a mechanistic explanation of species coexistence along a niche axis (i.e. organismic volume). We based our model on empirically measured quantities, minimal ecological assumptions and stochastic processes. In nature, we found aggregated patterns of species biovolume (i.e. clumps) along the volume axis and a peak in species richness. Both patterns were reproduced by the MLVC model. Observed clumps corresponded to niche zones (volumes) where species fitness was highest, or where fitness was equal among competing species. The latter implies the action of equalizing processes, which would suggest emergent neutrality as a plausible mechanism to explain community patterns. PMID:21177680

  19. Grain Unloading Of Arsenic Species In Rice

    Science.gov (United States)

    Rice (Oryza sativa) is the staple food for over half the world's population yet may represent a significant dietary source of inorganic arsenic (As), a nonthreshold, class 1 human carcinogen. Rice grain As is dominated by the inorganic species, and the organic species dim...

  20. Equilibrium Bird Species Diversity in Atlantic Islands

    NARCIS (Netherlands)

    Valente, Luis; Illera, Juan Carlos; Havenstein, Katja; Pallien, Tamara; Etienne, Rampal S.; Tiedemann, Ralph

    2017-01-01

    Half a century ago, MacArthur and Wilson proposed that the number of species on islands tends toward a dynamic equilibrium diversity around which species richness fluctuates [1]. The current prevailing view in island biogeography accepts the fundamentals of MacArthur and Wilson's theory [2] but

  1. The described species of the family Sacculinidae

    NARCIS (Netherlands)

    Boschma, H.

    1955-01-01

    I. INTRODUCTION AND KEYS OF GENERA AND SPECIES The present paper contains the data concerning the synonymy and the figures of the Sacculinidae, compiled from the various publications dealing with species of the family, to bring the scattered data together in a general survey. The keys contain all th

  2. A new species of Zygogynum (Winteraceae)

    NARCIS (Netherlands)

    Sampson, F.B.

    1983-01-01

    A new species, Zygogynum vinkii, is described within the woody Ranalean family Winteraceae. It differs from other species of the endemic New Caledonian genus in having 302-371 stamens per flower. Unspecialized cells of the lower leaf surface are covered with cuticular papillae of a type hitherto unr

  3. Species hybridization in the genus Pinus

    Science.gov (United States)

    Peter W. Garrett

    1979-01-01

    Results of a breeding program in which a large number of pine species were tested indicate that a number of species and hybrids may be useful in the northeastern United States. Austrian black pine x Japanese black pine and hybrids containing Japanese red pine all had good growth rates. While none of the soft pines grew faster than eastern white pine, a number of...

  4. New species of Maerua (Capparaceae) from Angola

    NARCIS (Netherlands)

    Abreu, J.A.; Martins, E.S.; Catarino, L.

    2014-01-01

    Genus Maerua has around 60 species represented on the African continent, of which three have been reported for Angola. Two new species of Maerua (Capparaceae) from Angola are here described. Both are closely similar to M. juncea subsp. juncea, being distinguished by floral traits such as the recepta

  5. COMPUTATIONAL RESOURCES FOR BIOFUEL FEEDSTOCK SPECIES

    Energy Technology Data Exchange (ETDEWEB)

    Buell, Carol Robin [Michigan State University; Childs, Kevin L [Michigan State University

    2013-05-07

    While current production of ethanol as a biofuel relies on starch and sugar inputs, it is anticipated that sustainable production of ethanol for biofuel use will utilize lignocellulosic feedstocks. Candidate plant species to be used for lignocellulosic ethanol production include a large number of species within the Grass, Pine and Birch plant families. For these biofuel feedstock species, there are variable amounts of genome sequence resources available, ranging from complete genome sequences (e.g. sorghum, poplar) to transcriptome data sets (e.g. switchgrass, pine). These data sets are not only dispersed in location but also disparate in content. It will be essential to leverage and improve these genomic data sets for the improvement of biofuel feedstock production. The objectives of this project were to provide computational tools and resources for data-mining genome sequence/annotation and large-scale functional genomic datasets available for biofuel feedstock species. We have created a Bioenergy Feedstock Genomics Resource that provides a web-based portal or clearing house for genomic data for plant species relevant to biofuel feedstock production. Sequence data from a total of 54 plant species are included in the Bioenergy Feedstock Genomics Resource including model plant species that permit leveraging of knowledge across taxa to biofuel feedstock species.We have generated additional computational analyses of these data, including uniform annotation, to facilitate genomic approaches to improved biofuel feedstock production. These data have been centralized in the publicly available Bioenergy Feedstock Genomics Resource (http://bfgr.plantbiology.msu.edu/).

  6. Xanthomendoza borealis - a bipolar lichen species

    DEFF Research Database (Denmark)

    LIndblom, Louise; Søchting, Ulrik

    It has been uncertain whether the two xanthorioid taxa known as Xanthoria mawsonii and Xanthomen-doza borealis truly are distinct species or if they should best be treated as one species. They are morphologically very similar, but inhabit two disjunct geographical areas, that is, circumpolar on t...

  7. Invasive species unchecked by climate - response

    DEFF Research Database (Denmark)

    Burrows, Michael T.; Schoeman, David S.; Duarte, Carlos M.;

    2012-01-01

    Hulme points out that observed rates of range expansion by invasive alien species are higher than the median speed of isotherm movement over the past 50 years, which in turn has outpaced the rates of climate-associated range changes of marine and terrestrial species. This is not surprising, given...

  8. Multivariate analisys of species from Cucurbitaceae family

    Directory of Open Access Journals (Sweden)

    Mladenović Emina

    2012-01-01

    Full Text Available Species from Cucurbitaceae family are not widely present in Serbia, although because of their morphological and decorative features deserve more attention. The aim of this paper was to study the morphological variability and usage of ten species of the Cucurbiataceae family. Based on genetic variability, species were grouped into 8 clusters. Fruit characteristics of most investigated species showed great similarity and the greatest differences were attained for flower and fruit characteristics. The longest was the fruit of Trichosanthes cucumerina (46.2 cm, while the shortest of Cucumis myriocarpus (3.4 cm which had the smallest circumference as well (4.4 cm. The largest circumference of fruit was recorded for the species Cucumis aculeatus (16.4 cm. In terms of fruit color Momordica balsamina had a red fruit, allocated from other species whose fruits were in various shades of green. Variability is reflected in large variations in size, shape and color of fruit. Considerating that usages of these species are multiple (food for humans and animals, ornamental studyed species deserve special attention in their further propagation and use.

  9. Taxonomy of Penicillium citrinum and related species

    NARCIS (Netherlands)

    Houbraken, J.; Frisvad, J.C.; Samson, R.A.

    2010-01-01

    Penicillium citrinum and related species have been examined using a combination of partial beta-tubulin, calmodulin and ITS sequence data, extrolite patterns and phenotypic characters. It is concluded that seven species belong to the series Citrina. Penicillium sizovae and Penicillium steckii are re

  10. Highlighting Astyanax Species Diversity through DNA Barcoding

    Science.gov (United States)

    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

  11. Hitherto unreported Agaricus species of Central India

    Directory of Open Access Journals (Sweden)

    MAHENDRA KUMAR RAI

    2010-11-01

    Full Text Available Karwa A, Rai MK. 2010. Hitherto unreported Agaricus species of Central India. Nusantara Bioscience 2: 141-145. Melghat forest region from Central India was surveyed for occurrence of medicinal and culinary mushrooms during the years 2005-2008. Out of total 153 species, ten species of Agaricus were recorded from different localities. Of these, seven species namely Agaricus bitorquis, A. subrufescens, A. augustus, A. placomyces, A. essettei, A. basioanolosus and Agaricus sp. nov (a new species are being reported for the first time from the region. The commercial button mushroom Agaricus bisporus lacks good breeding characters due to its bisporic nature. These wild cousins of the button mushroom can definitely prove to be a good source of genetic manipulations to the existing strains and also to develop new strains with improved characters.

  12. Allium species poisoning in dogs and cats

    Directory of Open Access Journals (Sweden)

    BS Salgado

    2011-01-01

    Full Text Available Dogs and cats are the animals that owners most frequently seek assistance for potential poisonings, and these species are frequently involved with toxicoses due to ingestion of poisonous food. Feeding human foodstuff to pets may prove itself dangerous for their health, similarly to what is observed in Allium species toxicosis. Allium species toxicosis is reported worldwide in several animal species, and the toxic principles present in them causes the transformation of hemoglobin into methemoglobin, consequently resulting in hemolytic anemia with Heinz body formation. The aim of this review is to analyze the clinicopathologic aspects and therapeutic approach of this serious toxicosis of dogs and cats in order to give knowledge to veterinarians about Allium species toxicosis, and subsequently allow them to correctly diagnose this disease when facing it; and to educate pet owners to not feed their animals with Allium-containg food in order to better control this particular life-threatening toxicosis.

  13. The Drosophila flavopilosa species group (Diptera, Drosophilidae)

    Science.gov (United States)

    Robe, Lizandra J.; De Ré, Francine Cenzi; Ludwig, Adriana; Loreto, Elgion L.S.

    2013-01-01

    The D. flavopilosa group encompasses an ecologically restricted set of species strictly adapted to hosting flowers of Cestrum (Solanaceae). This group presents potential to be used as a model to the study of different questions regarding ecologically restricted species macro and microevolutionary responses, geographical vs. ecological speciation and intra and interspecific competition. This review aims to revisit and reanalyze the patterns and processes that are subjacent to the interesting ecological and evolutionary properties of these species. Biotic and abiotic niche properties of some species were reanalyzed in face of ecological niche modeling approaches in order to get some insights into their ecological evolution. A test of the potential of DNA-Barcoding provided evidences that this technology may be a way of overcoming difficulties related to cryptic species differentiation. The new focus replenishes the scenario with new questions, presenting a case where neither geographical nor ecological speciation may be as yet suggested. PMID:23459119

  14. Metabolite production by differnt Ulocladium species

    DEFF Research Database (Denmark)

    Andersen, Birgitte; Hollensted, Morten

    2008-01-01

    Ulocladium, which is phylogenetically related to Alternaria, contains species that are food spoilers and plant pathogens, but also species that have potential as enzyme producers and bio-control agents. Ulocladium spp. are often found on dead vegetation, in soil, air and dust, but also on food...... and feedstuffs and on water-damaged building materials. The aim was to study the morphological and chemical diversity within the genus Ulocladium. Cultures of 52 Ulocladium strains were identified morphologically, and then extracted and analyzed using automated Chemical Image Analysis. Production of individual...... metabolites was correlated to species identity and source of isolation (substratum). Chemical analyses corroborated the morphological identifications and showed the existence of several species species-specific metabolites, of which most were known Compounds. The production of curvularins was specific...

  15. Region effects influence local tree species diversity.

    Science.gov (United States)

    Ricklefs, Robert E; He, Fangliang

    2016-01-19

    Global patterns of biodiversity reflect both regional and local processes, but the relative importance of local ecological limits to species coexistence, as influenced by the physical environment, in contrast to regional processes including species production, dispersal, and extinction, is poorly understood. Failure to distinguish regional influences from local effects has been due, in part, to sampling limitations at small scales, environmental heterogeneity within local or regional samples, and incomplete geographic sampling of species. Here, we use a global dataset comprising 47 forest plots to demonstrate significant region effects on diversity, beyond the influence of local climate, which together explain more than 92% of the global variation in local forest tree species richness. Significant region effects imply that large-scale processes shaping the regional diversity of forest trees exert influence down to the local scale, where they interact with local processes to determine the number of coexisting species.

  16. The Porphyra species of Helgoland (Bangiales, Rhodophyta)

    Science.gov (United States)

    Kornmann, P.; Sahling, P.-H.

    1991-03-01

    This revision of seven Porphyra species of Helgoland was based on a study of the structure of their fertile thalli and the behaviour of their spores. Regarding the reproductive organization the species may be arranged in two groups. P. leucosticta and P. purpureo-violacea are obligate monoecious species. Asexual thalli have never been observed in the field. The other five species are generally dioecious. Isomorphic sexual thalli and asexually propagating ones are mixed in uniform populations. Carpospores originating from sexual fusion develop into the diploid Conchocelis phase. Sporangia of asexual plants, though homologous in formation, produce spores of different kinds: aplanospores that give rise to the vegetative thallus directly (in P. umbilicalis, P. insolita n. sp. and P. ochotensis) and spores that develop into haploid Conchocelis (in P. laciniata and in P. linearis). P. laciniata — formerly considered synonymous with P. purpurea — is an independent species.

  17. ALIEN SPECIES: THEIR ROLE IN AMPHIBIAN POPULATION DECLINES AND RESTORATION

    Science.gov (United States)

    Alien species (also referred to as exotic, invasive, introduced, or normative species) have been implicated as causal agents in population declines of many amphibian species. Herein, we evaluate the relative contributions of alien species and other factors in adversely affecting ...

  18. 78 FR 24432 - Receipt of Applications for Endangered Species Permits

    Science.gov (United States)

    2013-04-25

    ..., tag, release) 56 freshwater mussel species, 5 snail species, 7 fish species, and 1 species of turtle... (Eretmochelys imbricata), leatherback (Dermochelys coriacea), green (Chelonia mydas), loggerhead (Caretta caretta), and olive ridley (Lepidochelys olivacea) sea turtles for veterinary treatment, release...

  19. 75 FR 38069 - Injurious Wildlife Species; Listing the Boa Constrictor, Four Python Species, and Four Anaconda...

    Science.gov (United States)

    2010-07-01

    ... Constrictor, Four Python Species, and Four Anaconda Species as Injurious Reptiles AGENCY: Fish and Wildlife... regulations to add Indian python (Python molurus, including Burmese python Python molurus bivittatus), reticulated python (Broghammerus reticulatus or Python reticulatus), Northern African python (Python...

  20. 75 FR 11808 - Injurious Wildlife Species; Listing the Boa Constrictor, Four Python Species, and Four Anaconda...

    Science.gov (United States)

    2010-03-12

    ... Constrictor, Four Python Species, and Four Anaconda Species as Injurious Reptiles AGENCY: Fish and Wildlife... to add Indian python (Python molurus, including Burmese python Python molurus bivittatus), reticulated python (Broghammerus reticulatus or Python reticulatus), Northern African python (Python...

  1. Genetic sorting of subordinate species in grassland modulated by intraspecific variation in dominant species.

    Directory of Open Access Journals (Sweden)

    Danny J Gustafson

    Full Text Available Genetic variation in a single species can have predictable and heritable effects on associated communities and ecosystem processes, however little is known about how genetic variation of a dominant species affects plant community assembly. We characterized the genetic structure of a dominant grass (Sorghastrum nutans and two subordinate species (Chamaecrista fasciculata, Silphium integrifolium, during the third growing season in grassland communities established with genetically distinct (cultivated varieties or local ecotypes seed sources of the dominant grasses. There were genetic differences between subordinate species growing in the cultivar versus local ecotype communities, indicating that intraspecific genetic variation in the dominant grasses affected the genetic composition of subordinate species during community assembly. A positive association between genetic diversity of S. nutans, C. fasciculata, and S. integrifolium and species diversity established the role of an intraspecific biotic filter during community assembly. Our results show that intraspecific variation in dominant species can significantly modulate the genetic composition of subordinate species.

  2. New species of Moenkhausia Eigenmann, 1903 (Characiformes: Characidae with comments on the Moenkhausia oligolepis species complex

    Directory of Open Access Journals (Sweden)

    Ricardo C. Benine

    Full Text Available A new species of Moenkhausia is described from tributaries of the rio Paraguay, Brazil. The new species is diagnosed from congeners by characters related to body coloration, the number of lateral line scales, the degree of poring of the lateral line, and number of scales rows above and below the lateral line. Molecular analyses using partial sequences of the mitochondrial gene Cytochrome Oxidase I from specimens of the new species and specimens belonging to morphologically similar species demonstrated that the new species is easily differentiated by their high genetic distance and by their position in the phylogenetic hypothesis obtained through the Maximum Parsimony methodology. The analyses of three samples of M. oligolepis also revealed that they have high genetic distances and belong to different monophyletic groups suggesting that this species corresponds to a species complex rather than a single species.

  3. Insights into the genus Diaporthe: phylogenetic species delimitation in the D. eres species complex

    Science.gov (United States)

    The genus Diaporthe comprises pathogenic, endophytic and saprobic species with both temperate and tropical distributions. Cryptic diversification, phenotypic plasticity and extensive host associations have long complicated accurate identifications of species in this genus. The delimitation of the ge...

  4. Calcifying species sensitivity distributions for ocean acidification.

    Science.gov (United States)

    Azevedo, Ligia B; De Schryver, An M; Hendriks, A Jan; Huijbregts, Mark A J

    2015-02-01

    Increasing CO2 atmospheric levels lead to increasing ocean acidification, thereby enhancing calcium carbonate dissolution of calcifying species. We gathered peer-reviewed experimental data on the effects of acidified seawater on calcifying species growth, reproduction, and survival. The data were used to derive species-specific median effective concentrations, i.e., pH50, and pH10, via logistic regression. Subsequently, we developed species sensitivity distributions (SSDs) to assess the potentially affected fraction (PAF) of species exposed to pH declines. Effects on species growth were observed at higher pH than those on species reproduction (mean pH10 was 7.73 vs 7.63 and mean pH50 was 7.28 vs 7.11 for the two life processes, respectively) and the variability in the sensitivity of species increased with increasing number of species available for the PAF (pH10 standard deviation was 0.20, 0.21, and 0.33 for survival, reproduction, and growth, respectively). The SSDs were then applied to two climate change scenarios to estimate the increase in PAF (ΔPAF) by future ocean acidification. In a high CO2 emission scenario, ΔPAF was 3 to 10% (for pH50) and 21 to 32% (for pH10). In a low emission scenario, ΔPAF was 1 to 4% (for pH50) and 7 to 12% (for pH10). Our SSDs developed for the effect of decreasing ocean pH on calcifying marine species assemblages can also be used for comparison with other environmental stressors.

  5. Persistent toxic substances in Mediterranean aquatic species.

    Science.gov (United States)

    Miniero, Roberto; Abate, Vittorio; Brambilla, Gianfranco; Davoli, Enrico; De Felip, Elena; De Filippis, Stefania P; Dellatte, Elena; De Luca, Silvia; Fanelli, Roberto; Fattore, Elena; Ferri, Fabiola; Fochi, Igor; Rita Fulgenzi, Anna; Iacovella, Nicola; Iamiceli, Anna Laura; Lucchetti, Dario; Melotti, Paolo; Moret, Ivo; Piazza, Rossano; Roncarati, Alessandra; Ubaldi, Alessandro; Zambon, Stefano; di Domenico, Alessandro

    2014-10-01

    Fish and fishery products may represent one of the main sources of dietary exposure to persistent toxic substances (PTSs) such as polychlorinated dibenzodioxins, dibenzofurans, and biphenyls; polybromodiphenyl ethers; organochlorine pesticides; perfluorooctanoic acid and perfluorooctane sulfonate; and inorganic mercury and methyl mercury. In this study, PTS contamination of Mediterranean fish and crustaceans caught in Italian coastal waters was investigated in order to increase the representativeness of the occurrence database for wild species. The objectives were to verify the suitability of regulatory limits for PTSs, identify background concentrations values, if any, and examine the possible sources of variability when assessing the chemical body burdens of aquatic species. Twelve wild species of commercial interest and two farmed fish species were chosen. Excluding methyl mercury, chemical concentrations found in wild species fell generally towards the low ends of the concentration ranges found in Europe according to EFSA database and were quite lower than the tolerable maximum levels established in the European Union; farmed fish always showed contamination levels quite lower than those detected in wild species. The data obtained for wild species seemed to confirm the absence of local sources of contamination in the chosen sampling areas; however, species contamination could exceed regulatory levels even in the absence of specific local sources of contamination as a result of the position in the food web and natural variability in species' lifestyle. A species-specific approach to the management of contamination in aquatic organisms is therefore suggested as an alternative to a general approach based only on contaminant body burden. A chemical-specific analysis performed according to organism position in the food chain strengthened the need to develop this approach. Copyright © 2014 Elsevier B.V. All rights reserved.

  6. Pseudoabsence generation strategies for species distribution models.

    Directory of Open Access Journals (Sweden)

    Brice B Hanberry

    Full Text Available BACKGROUND: Species distribution models require selection of species, study extent and spatial unit, statistical methods, variables, and assessment metrics. If absence data are not available, another important consideration is pseudoabsence generation. Different strategies for pseudoabsence generation can produce varying spatial representation of species. METHODOLOGY: We considered model outcomes from four different strategies for generating pseudoabsences. We generating pseudoabsences randomly by 1 selection from the entire study extent, 2 a two-step process of selection first from the entire study extent, followed by selection for pseudoabsences from areas with predicted probability <25%, 3 selection from plots surveyed without detection of species presence, 4 a two-step process of selection first for pseudoabsences from plots surveyed without detection of species presence, followed by selection for pseudoabsences from the areas with predicted probability <25%. We used Random Forests as our statistical method and sixteen predictor variables to model tree species with at least 150 records from Forest Inventory and Analysis surveys in the Laurentian Mixed Forest province of Minnesota. CONCLUSIONS: Pseudoabsence generation strategy completely affected the area predicted as present for species distribution models and may be one of the most influential determinants of models. All the pseudoabsence strategies produced mean AUC values of at least 0.87. More importantly than accuracy metrics, the two-step strategies over-predicted species presence, due to too much environmental distance between the pseudoabsences and recorded presences, whereas models based on random pseudoabsences under-predicted species presence, due to too little environmental distance between the pseudoabsences and recorded presences. Models using pseudoabsences from surveyed plots produced a balance between areas with high and low predicted probabilities and the strongest

  7. Neosilba (Tephritoidea: Lonchaeidae) species reared from coffee in Brazil, with description of a new species

    Energy Technology Data Exchange (ETDEWEB)

    Striki, Pedro Carlos; Prado, Angelo Pires do, E-mail: apprado@unicamp.b [Universidade Estadual de Campinas (UNICAMP), SP (Brazil). Inst. de Biologia. Dept. de Parasitologia

    2006-07-01

    Neosilba species are believed to be secondary invaders of fruit, so, little attention has been paid to its presence in coffee fruits. In this article we present a key to Neosilba species present in coffee fruits and describe a new species that is considered a primary invader. We hope this will help researchers working with coffee fruits to better quantify the economic importance of Neosilba species associated with coffee fruits. (author)

  8. Eight known species of Aphelenchoides nematodes with description of a new species from Manipur, India.

    Science.gov (United States)

    Chanu, L Bina; Mohilal, N; Victoria, L; Shah, M Manjur

    2015-06-01

    Study of Aphelenchoides nematodes from different localities of Manipur were conducted for their documentation. During the study eight known and a new species were identified. Aphelenchoides aerialis sp. nov. differed from all other species of Aphelenchoides in having a tail without bifurcation and strong ventral mucro with single ventrosublateral caudal papillae in male. The known species along with the new species are described in the present study.

  9. Two new species of Simulium (Gomphostilbia) (Diptera: Simuliidae) from Cameron's Highlands, Peninsular Malaysia, with keys to 21 species of the Simulium asakoae species-group.

    Science.gov (United States)

    Takaoka, H; Sofian-Azirun, M; Ya'cob, Z; Hashim, R

    2014-02-14

    Two new black fly species, Simulium (Gomphostilbia) brinchangense and S. (G.) tanahrataense, are described on the basis of reared adult females, males, pupae and larvae from Cameron's Highlands, Peninsular Malaysia. These new species are assigned to the asakoae species-group within Simulium (Gomphostilbia) and taxonomic notes are given to distinguish each new species from six known species in Malaysia. Revised keys to identify all 21 species including 13 species from other countries are provided for females, males, pupae and mature larvae. The species diversity of the asakoae species-group in Cameron's Highlands is briefly noted.

  10. 78 FR 52123 - Atlantic Highly Migratory Species; 2006 Consolidated Highly Migratory Species Fishery Management...

    Science.gov (United States)

    2013-08-22

    ... Species; 2006 Consolidated Highly Migratory Species Fishery Management Plan; Amendment 7 AGENCY: National... 7 to the 2006 Consolidated Highly Migratory Species (HMS) Fishery Management Plan (FMP) to control... quota categories utilize quota. In this notice, NMFS announces the dates and logistics for 10...

  11. The species of the genus Staelia (Rubiaceae) from Paraguay, a new species and new synonymous

    NARCIS (Netherlands)

    Salas, R.M.; Cabral, E.L.

    2010-01-01

    A new species of the genus Staelia is described and illustrated from the Boquerón department of Paraguay: S. nelidae. In total, three Staelia species have been recognized for Paraguay. Staelia hassleri is proposed as a new synonym of the widespread S. thymoides. A key to distinguish the new species

  12. Insecticide species sensitivity distributions: importance of test species selection and relevance to aquatic ecosystems

    NARCIS (Netherlands)

    Maltby, L.; Blake, N.; Brock, T.C.M.; Brink, van den P.J.

    2005-01-01

    Single-species acute toxicity data and (micro)mesocosm data were collated for 16 insecticides. These data were used to investigate the importance of test-species selection in constructing species sensitivity distributions (SSDs) and the ability of estimated hazardous concentrations (HCs) to protect

  13. Managing aquatic species of conservation concern in the face of climate change and invasive species.

    Science.gov (United States)

    Rahel, Frank J; Bierwagen, Britta; Taniguchi, Yoshinori

    2008-06-01

    The difficult task of managing species of conservation concern is likely to become even more challenging due to the interaction of climate change and invasive species. In addition to direct effects on habitat quality, climate change will foster the expansion of invasive species into new areas and magnify the effects of invasive species already present by altering competitive dominance, increasing predation rates, and enhancing the virulence of diseases. In some cases parapatric species may expand into new habitats and have detrimental effects that are similar to those of invading non-native species. The traditional strategy of isolating imperiled species in reserves may not be adequate if habitat conditions change beyond historic ranges or in ways that favor invasive species. The consequences of climate change will require a more active management paradigm that includes implementing habitat improvements that reduce the effects of climate change and creating migration barriers that prevent an influx of invasive species. Other management actions that should be considered include providing dispersal corridors that allow species to track environmental changes, translocating species to newly suitable habitats where migration is not possible, and developing action plans for the early detection and eradication of new invasive species.

  14. Random processes and geographic species richness patterns : why so few species in the north?

    NARCIS (Netherlands)

    Bokma, F; Bokma, J; Monkkonen, M

    In response to the suggestion that the latitudinal gradient in species richness is the result of stochastic processes of species distributions, we created a computer simulation program that enabled us to study random species distributions over irregularly shaped areas. Our model could not explain

  15. Rare species contribute disproportionately to the functional structure of species assemblages.

    Science.gov (United States)

    Leitão, Rafael P; Zuanon, Jansen; Villéger, Sébastien; Williams, Stephen E; Baraloto, Christopher; Fortunel, Claire; Mendonça, Fernando P; Mouillot, David

    2016-04-13

    There is broad consensus that the diversity of functional traits within species assemblages drives several ecological processes. It is also widely recognized that rare species are the first to become extinct following human-induced disturbances. Surprisingly, however, the functional importance of rare species is still poorly understood, particularly in tropical species-rich assemblages where the majority of species are rare, and the rate of species extinction can be high. Here, we investigated the consequences of local and regional extinctions on the functional structure of species assemblages. We used three extensive datasets (stream fish from the Brazilian Amazon, rainforest trees from French Guiana, and birds from the Australian Wet Tropics) and built an integrative measure of species rarity versus commonness, combining local abundance, geographical range, and habitat breadth. Using different scenarios of species loss, we found a disproportionate impact of rare species extinction for the three groups, with significant reductions in levels of functional richness, specialization, and originality of assemblages, which may severely undermine the integrity of ecological processes. The whole breadth of functional abilities within species assemblages, which is disproportionately supported by rare species, is certainly critical in maintaining ecosystems particularly under the ongoing rapid environmental transitions.

  16. Random processes and geographic species richness patterns : why so few species in the north?

    NARCIS (Netherlands)

    Bokma, F; Bokma, J; Monkkonen, M

    2001-01-01

    In response to the suggestion that the latitudinal gradient in species richness is the result of stochastic processes of species distributions, we created a computer simulation program that enabled us to study random species distributions over irregularly shaped areas. Our model could not explain la

  17. Culex Species Mosquitoes and Zika Virus.

    Science.gov (United States)

    Huang, Yan-Jang S; Ayers, Victoria B; Lyons, Amy C; Unlu, Isik; Alto, Barry W; Cohnstaedt, Lee W; Higgs, Stephen; Vanlandingham, Dana L

    2016-10-01

    Recent reports of Zika virus (ZIKV) isolates from Culex species mosquitoes have resulted in concern regarding a lack of knowledge on the number of competent vector species for ZIKV transmission in the new world. Although observations in the field have demonstrated that ZIKV isolation can be made from Culex species mosquitoes, the detection of ZIKV in these mosquitoes is not proof of their involvement in a ZIKV transmission cycle. Detection may be due to recent feeding on a viremic vertebrate, and is not indicative of replication in the mosquito. In this study, susceptibility of recently colonized Culex species mosquitoes was investigated. The results showed a high degree of refractoriness among members of Culex pipiens complex to ZIKV even when exposed to high-titer bloodmeals. Our finding suggests that the likelihood of Culex species mosquitoes serving as secondary vectors for ZIKV is very low, therefore vector control strategies for ZIKV should remain focused on Aedes species mosquitoes. Our demonstration that Culex quinquefasciatus from Vero Beach, FL, is refractory to infection with ZIKV is especially important and timely. Based on our data, we would conclude that the autochthonous cases of Zika in Florida are not due to transmission by C. quinquefasciatus, and so control efforts should focus on other species, logically Aedes aegypti and Aedes albopictus.

  18. Genetic variability in three Amazon parrot species

    Directory of Open Access Journals (Sweden)

    IF. Lopes

    Full Text Available Parrots of the genus Amazona are among the most threatened species of the Order Pscittaciformes. This work describes allozyme polymorphisms in three Amazon parrot species - the Blue-fronted Amazon (Amazona aestiva, the Orange-winged Amazon (Amazona amazonica, and the Festive Amazon (Amazona festiva -, and provides useful data for the evaluation of their genetic variability. We electrophoretically analyzed blood samples from 68 wild-caught individuals, maintained in captivity in three Brazilian zoos. Eight of the ten studied enzyme loci exhibited polymorphism. Glucosephosphate isomerase (Gpi proved to be a diagnostic locus for the identification of these Amazon species. The expected average heterozygosity of the Blue-fronted Amazon (0.060 differed significantly from the expected heterozygosities of the Orange-winged Amazon and the Festive Amazon (0.040 and 0.039, respectively. This result was discussed as a consequence of hybridization between two geographic A. aestiva subspecies, and alternatively as a particular trait of this species. Genetic variability of the Blue-fronted Amazon compared to birds in general is not low on a species-wide level, despite the fact that this parrot is one of the most illegally traded species. Allozyme analysis proved to be an useful tool in monitoring the genetic variation within the genus Amazona and can be applied in the management program of other threatened species of this genus.

  19. Pushing the pace of tree species migration.

    Directory of Open Access Journals (Sweden)

    Eli D Lazarus

    Full Text Available Plants and animals have responded to past climate changes by migrating with habitable environments, sometimes shifting the boundaries of their geographic ranges by tens of kilometers per year or more. Species migrating in response to present climate conditions, however, must contend with landscapes fragmented by anthropogenic disturbance. We consider this problem in the context of wind-dispersed tree species. Mechanisms of long-distance seed dispersal make these species capable of rapid migration rates. Models of species-front migration suggest that even tree species with the capacity for long-distance dispersal will be unable to keep pace with future spatial changes in temperature gradients, exclusive of habitat fragmentation effects. Here we present a numerical model that captures the salient dynamics of migration by long-distance dispersal for a generic tree species. We then use the model to explore the possible effects of assisted colonization within a fragmented landscape under a simulated tree-planting scheme. Our results suggest that an assisted-colonization program could accelerate species-front migration rates enough to match the speed of climate change, but such a program would involve an environmental-sustainability intervention at a massive scale.

  20. Antagonism of Microsporum species by soil fungi.

    Science.gov (United States)

    Singh, I; Dixit, A K; Kushwaha, R K S

    2010-01-01

    Eighteen fungi isolated from soil by hair bating method were tested against soil inhabiting Microsporum equinum, Microsporum fulvum, Microsporum gypseum and Microsporum racemosum for their antagonistic interactions. Colony inhibition during dual cultures showed inhibition of all the four Microsporum species. The maximum inhibition of M. equinum, M. fulvum, M. gypseum and M. racemosum was caused by Chrysosporium keratinophilum, Chrysosporium tropicum, Curvularia lunata and Chrysosporium lucknowense in dual cultures. On the other hand, M. fulvum showed maximum inhibition of Macrophomina phaseolina (70.1%) while M. equinum, M. gypseum and M. racemosum showed maximum inhibition of Colletotrichum gloeosporoides. Staling products of C. lucknowense accelerated growth of all Microsporum species, C. keratinophilum 3 and Chrysosporium evolceaunui and M. phaseolina accelerated growth of two species of Microsporum. Staling product of Alternaria alternata was most inhibitory. Culture filtrates of Trichophyton vanbreseughemii accelerated the growth of all the four Microsporum species and C. tropicum, C. lucknowense accelerated growth of two species, while Botryotrichum piluliferum accelerated growth of three species of Microsporum. Volatiles showed inhibition of all the Microsporum species ranging from 0.33 to 57.2% except in case of M. fulvum. Lysis of Microsporum mycelium was the most common feature.

  1. Species ages in neutral biodiversity models.

    Science.gov (United States)

    Chisholm, Ryan A; O'Dwyer, James P

    2014-05-01

    Biogeography seeks to understand the mechanisms that drive biodiversity across long temporal and large spatial scales. Theoretical models of biogeography can be tested by comparing their predictions of quantities such as species ages against empirical estimates. It has previously been claimed that the neutral theory of biodiversity and biogeography predicts species ages that are unrealistically long. Any improved theory of biodiversity must rectify this problem, but first it is necessary to quantify the problem precisely. Here we provide analytical expressions for species ages in neutral biodiversity communities. We analyse a spatially implicit metacommunity model and solve for both the zero-sum and non-zero-sum cases. We explain why our new expressions are, in the context of biodiversity, usually more appropriate than those previously imported from neutral molecular evolution. Because of the time symmetry of the spatially implicit neutral model, our expressions also lead directly to formulas for species persistence times and species lifetimes. We use our new expressions to estimate species ages of forest trees under a neutral model and find that they are about an order of magnitude shorter than those predicted previously but still unrealistically long. In light of our results, we discuss different models of biogeography that may solve the problem of species ages.

  2. Evaluation of seedoil containing wild species

    Energy Technology Data Exchange (ETDEWEB)

    Hondelmann, W.; Radatz, W.

    1984-01-01

    Six herbaceous seedoil containing wild species were evaluated with respect to agronomic traits and chemical characteristics of their seeds. Furthermore, the inherent wild-type characters were defined and possibilities for their improvement discussed. It could be demonstrated that the vegetation cycle of the annual species was comparable to that of summer rape; biennials had a naturally exceptional position. Because of the very common seed-fall no exact data on yield were possible. Nevertheless, the starting point for grain yield can be considered encouraging. Also seed size (1000-kernel-weight) is favourable. Moreover, the species in question generally are adapted to modern cultivation techniques. With respect to oil content and fatty acid composition most of these species exhibited means and ranges, which are considered favourable. But, some species need a broader genetic base. From oleic acid (C18:1) to nervonic acid (24:1) all characteristic unsaturated long-chained fatty acids at least once show an order, that seems interesting for exploitation. Thus, besides seed oil quantity there is a qualitative aspect. The various wild-type characteristics are of more or less importance depending on the species in question. Using suitable selection methods, which succeeded in two cases, and for some species also a larger variability it seems to be possible to achieve an improved character expression in the long run, which finally would provide base material for breeder's use.

  3. Recent advances in probabilistic species pool delineations

    Directory of Open Access Journals (Sweden)

    Dirk Nikolaus Karger

    2016-07-01

    Full Text Available A species pool is the set of species that could potentially colonize and establish within a community. It has been a commonly used concept in biogeography since the early days of MacArthur and Wilson’s work on Island Biogeography. Despite their simple and appealing definition, an operational application of species pools is bundled with a multitude of problems, which have often resulted in arbitrary decisions and workarounds when defining species pools. Two recently published papers address the operational problems of species pool delineations, and show ways of delineating them in a probabilistic fashion. In both papers, species pools were delineated using a process-based, mechanistical approach, which opens the door for a multitude of new applications in biogeography. Such applications include detecting the hidden signature of biotic interactions, disentangling the geographical structure of community assembly processes, and incorporating a temporal extent into species pools. Although similar in their conclusions, both ‘probabilistic approaches’ differ in their implementation and definitions. Here I give a brief overview of the differences and similarities of both approaches, and identify the challenges and advantages in their application.

  4. How variation between individuals affects species coexistence.

    Science.gov (United States)

    Hart, Simon P; Schreiber, Sebastian J; Levine, Jonathan M

    2016-08-01

    Although the effects of variation between individuals within species are traditionally ignored in studies of species coexistence, the magnitude of intraspecific variation in nature is forcing ecologists to reconsider. Compelling intuitive arguments suggest that individual variation may provide a previously unrecognised route to diversity maintenance by blurring species-level competitive differences or substituting for species-level niche differences. These arguments, which are motivating a large body of empirical work, have rarely been evaluated with quantitative theory. Here we incorporate intraspecific variation into a common model of competition and identify three pathways by which this variation affects coexistence: (1) changes in competitive dynamics because of nonlinear averaging, (2) changes in species' mean interaction strengths because of variation in underlying traits (also via nonlinear averaging) and (3) effects on stochastic demography. As a consequence of the first two mechanisms, we find that intraspecific variation in competitive ability increases the dominance of superior competitors, and intraspecific niche variation reduces species-level niche differentiation, both of which make coexistence more difficult. In addition, individual variation can exacerbate the effects of demographic stochasticity, and this further destabilises coexistence. Our work provides a theoretical foundation for emerging empirical interests in the effects of intraspecific variation on species diversity.

  5. Species coexistence in a changing world

    Directory of Open Access Journals (Sweden)

    Fernando eValladares

    2015-10-01

    Full Text Available The consequences of global change for the maintenance of species diversity will depend on the sum of each species responses to the environment and on the interactions among them. A wide ecological literature supports that these species-specific responses can arise from factors related to life strategies, evolutionary history and intraspecific variation, and also from environmental variation in space and time. In the light of recent advances from coexistence theory combined with mechanistic explanations of diversity maintenance, we discuss how global change drivers can influence species coexistence. We revise the importance of both competition and facilitation for understanding coexistence in different ecosystems, address the influence of phylogenetic relatedness, functional traits, phenotypic plasticity and intraspecific variability, and discuss lessons learnt from invasion ecology. While most previous studies have focused their efforts on disentangling the mechanisms that maintain the biological diversity in species-rich ecosystems such as tropical forests, grasslands and coral reefs, we argue that much can be learnt from pauci-specific communities where functional variability within each species, together with demographic and stochastic processes becomes key to understand species interactions and eventually community responses to global change.

  6. Morphological Research on Indigenous Sambucus Species Pollen

    Directory of Open Access Journals (Sweden)

    Mircea TAMAS

    2009-06-01

    Full Text Available The pollen grains have a definite shape, size, colour, structure for each species, genus and family and these characters are useful for systematical botany. The pollen has nutritive properties due to its content: proteins, lipids, carbohydrates, vitamins, hormones and minerals. In the Romanian flora vegetate three species of Sambucus, but only S. nigra L. (elder or black elder supplies a vegetal medical product, Sambuci flos or elder flowers, whereas the others species S. ebulus L. (dwarf elder and S. racemosa L. (mountain elder or red elder are considered adulterations. The pollen of Sambucus species were already studied using optical microscopy (Tarnavschi et al., but the images are in one single layout, therefore the structure details cannot be easily notice. In this context the pollen grains of the three species already mentioned above were studied by SEM (Scanning Electron Microscopy. The results demonstrated that this pollen have a small-middle size, oblat-sphaeroidal-prolat shape, threecolpat and the exine adornments are of reticulate type, haemitectate with sticks in the meshs of polygonale net. The flavonoids content is lower than in others species (0.146-0.564 %. The SEM analyse of Sambucus pollen allow a reliable identification of the genus but less for the species.

  7. Economics of Harmful Invasive Species: A Review

    Directory of Open Access Journals (Sweden)

    George Marbuah

    2014-07-01

    Full Text Available The purpose of this study is to review theoretical and empirical findings in economics with respect to the challenging question of how to manage invasive species. The review revealed a relatively large body of literature on the assessment of damage costs of invasive species; single species and groups of species at different geographical scales. However, the estimated damage costs show large variation, from less than 1 million USD to costs corresponding to 12% of gross domestic product, depending on the methods employed, geographical scale, and scope with respect to inclusion of different species. Decisions regarding optimal management strategies, when to act in the invasion chain and which policy to choose, have received much less attention in earlier years, but have been subject to increasing research during the last decade. More difficult, but also more relevant policy issues have been raised, which concern the targeting in time and space of strategies under conditions of uncertainty. In particular, the weighting of costs and benefits from early detection and mitigation against the uncertain avoidance of damage with later control, when the precision in targeting species is typically greater is identified as a key challenge. The role of improved monitoring for detecting species and their spread and damage has been emphasized, but questions remain on how to achieve this in practice. This is in contrast to the relatively large body of literature on policies for mitigating dispersal by trade, which is regarded as one of the most important vectors for the spread of invasive species. On the other hand, the literature on how to mitigate established species, by control or adaptation, is much more scant. Studies evaluating causes for success or failure of policies against invasive in practice are in principal non-existing.

  8. 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.

  9. Chromosome studies of European cyprinid fishes: cross-species painting reveals natural allotetraploid origin of a Carassius female with 206 chromosomes.

    Science.gov (United States)

    Knytl, M; Kalous, L; Symonová, R; Rylková, K; Ráb, P

    2013-01-01

    A single female with 206 chromosomes and another 26 females with 156 chromosomes identified as Prussian carp, Carassius gibelio, and 5 individuals with 100 chromosomes identified as crucian carp, C. carassius, were sampled during field survey in one locality in the upper Elbe River. To identify the origin of females with high chromosome numbers, comparative karyotype analysis, GISH, with whole C. carassius DNA as probe and phylogenetic positions of sampled individuals revealed by cytochrome b mitochondrial marker were performed. GISH showed consistently bright labeling of 50 chromosomal elements out of 206, corresponding to the haploid chromosome number of C. carassius. The position of these females with high chromosome numbers in a reconstructed phylogenetic tree was within the clade of C. gibelio, documenting its affiliation to C. gibelio mitochondrial, i.e. maternal lineage. Our findings indicated that the mother of the female with high chromosome numbers was a gynogenetically reproducing 156-chromosome C. gibelio female and the father a bisexually reproducing C. carassius male. We, therefore, hypothesized that the C. gibelio × C. carassius allopolyploid female with 206 chromosomes arose by a mechanism of sperm genome addition to an unreduced egg of the mother.

  10. Reservoirs of non-baumannii Acinetobacter species

    Directory of Open Access Journals (Sweden)

    Ahmad eAl Atrouni

    2016-02-01

    Full Text Available Acinetobacter spp are ubiquitous gram negative and non fermenting coccobacilli that have the ability to occupy several ecological niches including environment, animals and human. Among the different species, Acinetobacter baumannii has evolved as global pathogen causing wide range of infection. Since the implementation of molecular techniques, the habitat and the role of non baumannii Acinetobacter in human infection have been elucidated. In addition, several new species have been described. In the present review, we summarize the recent data about the natural reservoir of non-baumannii Acinetobacter including the novel species that have been described for the first time from environmental sources and reported during the last years.

  11. Fort Collins Science Center: Invasive Species Science

    Science.gov (United States)

    Stohlgren, Tom

    2004-01-01

    Invasive, non-native species of plants, animals, and disease organisms adversely affect the ecosystems they enter. Like "biological wildfires," they can quickly spread, and they affect nearly all terrestrial and aquatic ecosystems. Invasive species have become the greatest environmental challenge of the 21st century in terms of economic, environmental, and human health costs, with an estimated impact in the U.S. of over $138 billion per year. Managers of Department of the Interior and other public and private lands and waters rank invasive species as their top resource management problem.

  12. Species Diversity Enhances Predator Growth Rates

    Directory of Open Access Journals (Sweden)

    Mark H. Olson

    2007-01-01

    Full Text Available Predators can be important top-down regulators of community structure and are known to have both positive and negative effects on species diversity. However, little is known about the reciprocal effects of species diversity on predators. Across a set of 80 lakes in Connecticut, USA, we found a strong positive correlation between prey species diversity (using the Shannon-Weiner Diversity Index and growth rates of largemouth bass (Micropterus salmoides. This correlation was strongest for small predators and decreased with body size. Although the underlying mechanisms are not known, the correlation is not driven by total fish abundance, predator abundance, or productivity.

  13. Reservoirs of Non-baumannii Acinetobacter Species.

    Science.gov (United States)

    Al Atrouni, Ahmad; Joly-Guillou, Marie-Laure; Hamze, Monzer; Kempf, Marie

    2016-01-01

    Acinetobacter spp. are ubiquitous gram negative and non-fermenting coccobacilli that have the ability to occupy several ecological niches including environment, animals and human. Among the different species, Acinetobacter baumannii has evolved as global pathogen causing wide range of infection. Since the implementation of molecular techniques, the habitat and the role of non-baumannii Acinetobacter in human infection have been elucidated. In addition, several new species have been described. In the present review, we summarize the recent data about the natural reservoir of non-baumannii Acinetobacter including the novel species that have been described for the first time from environmental sources and reported during the last years.

  14. A series of Xerophilic Chrysosporium species

    DEFF Research Database (Denmark)

    Skou, Jens-Peder

    1992-01-01

    Xerophilic Chrysosporium species related to C. farinicola were often isolated from uneaten provisions (pollen-and-nectar mixture) of mason bees (Osmia spp.). The fungi have an optimal growth rate on media which are 2 to 3 molar in regard to glucose, exhibit some growth up to 3.6 molar glucose, an......, and initiate a new increased growth rate when the glucose crystallizes out from these supersaturated media. Seven of these species and three varieties are described and separated into a Farinicola series of Chrysosporium species....

  15. [Lectins of Dryopteris Adans fern species].

    Science.gov (United States)

    Basheka, O V; Stetsenko, N M; Pogorila, N F

    1999-01-01

    Lectin activity of three ferns species (Dryopteris bushiana Fom., D. laeta (Kom.) C. Chr, D. pseudomas (Wollaston) Holub et Pouzar) has been studied. We used hemagglutination reaction albumin and globulin fractions of fronds and rhizomes extracts with rat erythrocytes. The frond extract of D. pseudomas have shown higher activity as compared with other extracts. The lectin activity of D. laeta leaves was absent. The rhizomes of all three fern species could be characterized as high activity. Based on lectin activity the species were placed as follows order: D. buschiana > D. pseudomas > D. laeta. The dependence with lectin activity and elements (Mn, Fe, Cu, Ni, Zn, Pb, Rb, Sr) content were not found.

  16. Fatty acid composition of forage herb species

    DEFF Research Database (Denmark)

    Warner, D.; Jensen, Søren Krogh; Cone, J.W.

    2010-01-01

    The use of alternative forage species in grasslands for intensive livestock production is receiving renewed attention. Data on fatty acid composition of herbs are scarce, so four herbs (Plantago lanceolata, Achillea millefolium, Cichorium intybus, Pastinaca sativa) and one grass species (timothy......, Phleum pratense) were sown in a cutting trial. The chemical composition and concentration of fatty acids (FA) of individual species were determined during the growing season. Concentrations of crude protein and FA were generally higher in the herbs than in timothy. C. intybus had the highest nutritive...

  17. Dna c-values of 20 invasive alien species and 3 native species in south china

    Directory of Open Access Journals (Sweden)

    Gong Ni

    2014-01-01

    Full Text Available Cultivated fields and forests in South China are experiencing serious damage due to invasive alien plants. We investigated the relation between DNA C-values and invasiveness. The DNA C-values of 23 species ranged from 0.39 pg to 3.37 pg. Herbs, perennials and native species had higher mean DNA C-values than shrubs, annuals and invasive alien species. DNA C-values decreased with increasing invasiveness. Paederia scandens, a harmful native species, has the lowest DNA C-value among the perennials, indicating that native species with low nuclear content may also possess an invasive potential.

  18. Interpretation of the biological species concept from interspecific hybridization of two Helicoverpa species

    Institute of Scientific and Technical Information of China (English)

    WANG ChenZhu

    2007-01-01

    The biological species concept defines species in terms of interbreeding. Interbreeding between species is prevented by reproductive isolation mechanisms. Based on our results of interspecific hybridization between Helicoverpa armigera and Helicoverpa assulta, reproductive isolation mechanisms of the two species are analyzed. A combination of prezygotic factors (absent sex attraction and physical incompatibility of the genitalia) and postzygotic factors (female absence and partial sterility in F1 hybrids) causes reproductive isolation of the two species. In addition, the role of interspecific hybridization in speciation is discussed.

  19. An updated checklist of mosquito species (Diptera: Culicidae) from Madagascar.

    Science.gov (United States)

    Tantely, Michaël Luciano; Le Goff, Gilbert; Boyer, Sébastien; Fontenille, Didier

    2016-01-01

    An updated checklist of 235 mosquito species from Madagascar is presented. The number of species has increased considerably compared to previous checklists, particularly the last published in 2003 (178 species). This annotated checklist provides concise information on endemism, taxonomic position, developmental stages, larval habitats, distribution, behavior, and vector-borne diseases potentially transmitted. The 235 species belong to 14 genera: Aedeomyia (3 species), Aedes (35 species), Anopheles (26 species), Coquillettidia (3 species), Culex (at least 50 species), Eretmapodites (4 species), Ficalbia (2 species), Hodgesia (at least one species), Lutzia (one species), Mansonia (2 species), Mimomyia (22 species), Orthopodomyia (8 species), Toxorhynchites (6 species), and Uranotaenia (73 species). Due to non-deciphered species complexes, several species remain undescribed. The main remarkable characteristic of Malagasy mosquito fauna is the high biodiversity with 138 endemic species (59%). Presence and abundance of species, and their association, in a given location could be a bio-indicator of environmental particularities such as urban, rural, forested, deforested, and mountainous habitats. Finally, taking into account that Malagasy culicidian fauna includes 64 species (27%) with a known medical or veterinary interest in the world, knowledge of their biology and host preference summarized in this paper improves understanding of their involvement in pathogen transmission in Madagascar. © M.L. Tantely et al., published by EDP Sciences, 2016.

  20. An updated checklist of mosquito species (Diptera: Culicidae from Madagascar

    Directory of Open Access Journals (Sweden)

    Tantely Michaël Luciano

    2016-01-01

    Full Text Available An updated checklist of 235 mosquito species from Madagascar is presented. The number of species has increased considerably compared to previous checklists, particularly the last published in 2003 (178 species. This annotated checklist provides concise information on endemism, taxonomic position, developmental stages, larval habitats, distribution, behavior, and vector-borne diseases potentially transmitted. The 235 species belong to 14 genera: Aedeomyia (3 species, Aedes (35 species, Anopheles (26 species, Coquillettidia (3 species, Culex (at least 50 species, Eretmapodites (4 species, Ficalbia (2 species, Hodgesia (at least one species, Lutzia (one species, Mansonia (2 species, Mimomyia (22 species, Orthopodomyia (8 species, Toxorhynchites (6 species, and Uranotaenia (73 species. Due to non-deciphered species complexes, several species remain undescribed. The main remarkable characteristic of Malagasy mosquito fauna is the high biodiversity with 138 endemic species (59%. Presence and abundance of species, and their association, in a given location could be a bio-indicator of environmental particularities such as urban, rural, forested, deforested, and mountainous habitats. Finally, taking into account that Malagasy culicidian fauna includes 64 species (27% with a known medical or veterinary interest in the world, knowledge of their biology and host preference summarized in this paper improves understanding of their involvement in pathogen transmission in Madagascar.

  1. Species detection and individual assignment in species delimitation: can integrative data increase efficacy?

    Science.gov (United States)

    Edwards, Danielle L; Knowles, L Lacey

    2014-02-22

    Statistical species delimitation usually relies on singular data, primarily genetic, for detecting putative species and individual assignment to putative species. Given the variety of speciation mechanisms, singular data may not adequately represent the genetic, morphological and ecological diversity relevant to species delimitation. We describe a methodological framework combining multivariate and clustering techniques that uses genetic, morphological and ecological data to detect and assign individuals to putative species. Our approach recovers a similar number of species recognized using traditional, qualitative taxonomic approaches that are not detected when using purely genetic methods. Furthermore, our approach detects groupings that traditional, qualitative taxonomic approaches do not. This empirical test suggests that our approach to detecting and assigning individuals to putative species could be useful in species delimitation despite varying levels of differentiation across genetic, phenotypic and ecological axes. This work highlights a critical, and often overlooked, aspect of the process of statistical species delimitation-species detection and individual assignment. Irrespective of the species delimitation approach used, all downstream processing relies on how individuals are initially assigned, and the practices and statistical issues surrounding individual assignment warrant careful consideration.

  2. Phylogeny and species delimitation of the C-genome diploid species in Oryza

    Institute of Scientific and Technical Information of China (English)

    Li-Li ZANG; Xin-Hui ZOU; Fu-Min ZHANG; Ziheng YANG; Song GE

    2011-01-01

    The diploid Oryza species with C-genome type possesses abundant genes useful for rice improvement and provides parental donors of many tetraploid species with the C-genome (BBCC,CCDD).Despite extensive studies,the phylogenetic relationship among the C-genome species and the taxonomic status of some taxa remain controversial.In this study,we reconstructed the phylogeny of three diploid species with C-genome (Oryza officinalis,O.rhizomatis,and O.eichingeri) based on sequences of 68 nuclear single-copy genes.We obtained a fully resolved phylogenetic tree,clearly indicating the sister relationship of O.officinalis and O.rhizomatis,with O.eichingeri being the more divergent lineage.Incongruent phylogenies of the C-genome species found in previous studies might result from lineage sorting,introgression/hybridization and limited number of genetic markers used.We further applied a recently developed Bayesian species delimitation method to investigate the species status of the Sri Lankan and African O.eichingeri.Analyses of two datasets (68 genes with a single sample,and 10 genes with multiple samples) support the distinct species status of the Sri Lankan and African O.eichingeri.In addition,we evaluated the impact of the number of sampled individuals and loci on species delimitation.Our simulation suggests that sampling multiple individuals is critically important for species delimitation,particularly for closely related species.

  3. Recovery of imperiled species under the Endangered Species Act: The need for a new approach

    Science.gov (United States)

    Scott, J.M.; Goble, D.D.; Wiens, J.A.; Wilcove, D.S.; Bean, M.; Male, T.

    2005-01-01

    The recovery (delisting) of a threatened or endangered species is often accompanied by the expectation that conservation management of the species will no longer be necessary. However, the magnitude and pace of human impacts on the environment make it unlikely that substantial progress will be made in delisting many species unless the definition of "recovery" includes some form of active management. Preventing delisted species from again being at risk of extinction may require continuing, species-specific management actions. We characterize such species as "conservation-reliant", and suggest that viewing "recovery" as a continuum of states rather than as a simple "recovered/not recovered" dichotomy may enhance our ability to manage such species within the framework of the Endangered Species Act. With ongoing loss of habitat, disruption of natural disturbance regimes, and the increasing impacts of non-native invasive species, it is probable that the number of conservation-reliant species will increase. We propose the development of "recovery management agreements", with legally and biologically defensible contracts that would provide for continu-ing conservation management following delisting. The use of such formalized agreements will facilitate shared management responsibilities between federal wildlife agencies and other federal agencies, and with state, local, and tribal governments, as well as with private entities that have demonstrated the capability to meet the needs of conservation-reliant species. ?? The Ecological Society of America.

  4. Is geographic variation within species related to macroevolutionary patterns between species?

    Science.gov (United States)

    Fisher-Reid, M C; Wiens, J J

    2015-08-01

    The relationship between microevolution and macroevolution is a central topic in evolutionary biology. An aspect of this relationship that remains very poorly studied in modern evolutionary biology is the relationship between within-species geographic variation and among-species patterns of trait variation. Here, we tested the relationship between climate and morphology among and within species in the salamander genus Plethodon. We focus on a discrete colour polymorphism (presence and absence of a red dorsal stripe) that appears to be related to climatic distributions in a common, wide-ranging species (Plethodon cinereus). We find that this trait has been variable among (and possibly within) species for >40 million years. Furthermore, we find a strong relationship among species between climatic variation and within-species morph frequencies. These between-species patterns are similar (but not identical) to those in the broadly distributed Plethodon cinereus. Surprisingly, there are no significant climate-morphology relationships within most other polymorphic species, despite the strong between-species patterns. Overall, our study provides an initial exploration of how within-species geographic variation and large-scale macroevolutionary patterns of trait variation may be related. © 2015 European Society For Evolutionary Biology. Journal of Evolutionary Biology © 2015 European Society For Evolutionary Biology.

  5. Population dynamics of Trichoderma species in the rhizosphere of tobacco and four species form China

    Institute of Scientific and Technical Information of China (English)

    YU Ze-fen; ZHANG Ke-qin

    2004-01-01

    @@ To study the effect of tobacco growth on Trichoderma population, we investigated the occurrence of Trichoderma species in the rhizosphere of tobacco plant during the period from transplanting (June) to harvesting (October) and measured relative environmental factors. Eleven species of Trichoderma were isolated, among which T. harzianum, T. viride, T. hamatum, T. atroviride, T.longibrachiatum, T. virens, T. koningii were identified, other four species Ty1, Ty2, Ty3, Ty4are new species. Of the species which occurred at high frequencies, T. harzianum and T. hamatum were most abundant in the July and T. viride in the August. The occurrence of the above three abundant species correlates significantly with the developmental phase of tobacco and correlates apparently with the soil moisture content, but not with the temperature. For the other eight species,no obvious correlation was found between the above factors and them.

  6. Fingerprinting the Asterid species using subtracted diversity array reveals novel species-specific sequences.

    Directory of Open Access Journals (Sweden)

    Nitin Mantri

    Full Text Available BACKGROUND: Asterids is one of the major plant clades comprising of many commercially important medicinal species. One of the major concerns in medicinal plant industry is adulteration/contamination resulting from misidentification of herbal plants. This study reports the construction and validation of a microarray capable of fingerprinting medicinally important species from the Asterids clade. METHODOLOGY/PRINCIPAL FINDINGS: Pooled genomic DNA of 104 non-asterid angiosperm and non-angiosperm species was subtracted from pooled genomic DNA of 67 asterid species. Subsequently, 283 subtracted DNA fragments were used to construct an Asterid-specific array. The validation of Asterid-specific array revealed a high (99.5% subtraction efficiency. Twenty-five Asterid species (mostly medicinal representing 20 families and 9 orders within the clade were hybridized onto the array to reveal its level of species discrimination. All these species could be successfully differentiated using their hybridization patterns. A number of species-specific probes were identified for commercially important species like tea, coffee, dandelion, yarrow, motherwort, Japanese honeysuckle, valerian, wild celery, and yerba mate. Thirty-seven polymorphic probes were characterized by sequencing. A large number of probes were novel species-specific probes whilst some of them were from chloroplast region including genes like atpB, rpoB, and ndh that have extensively been used for fingerprinting and phylogenetic analysis of plants. CONCLUSIONS/SIGNIFICANCE: Subtracted Diversity Array technique is highly efficient in fingerprinting species with little or no genomic information. The Asterid-specific array could fingerprint all 25 species assessed including three species that were not used in constructing the array. This study validates the use of chloroplast genes for bar-coding (fingerprinting plant species. In addition, this method allowed detection of several new loci that can be

  7. Predicting fish species distribution in estuaries: Influence of species' ecology in model accuracy

    Science.gov (United States)

    França, Susana; Cabral, Henrique N.

    2016-10-01

    Current threats to biodiversity, combined with limited data availability, have made for species distribution models (SDMs) to be increasingly used due to their ability to predict species' potential distribution, by relating species occurrence with environmental estimates. Often used in ecology, conservation biology and environmental management, SDMs have been informing conservation strategies, and thus it is becoming crucial to understand how trustworthy their predictions are. Uncertainty in model predictions is expected, but knowing the origin of prediction errors may help reducing it. Indeed, uncertainty may be related not only with data quality and the modelling algorithm used, but also with species ecological characteristics. To investigate whether the performance of SDM's may vary with species' ecological characteristics, distribution models for 21 fish species occurring in estuaries from the Portuguese coast were examined. These models were built at two distinct spatial resolutions and seven environmental explanatory variables were used as predictors. SDMs' accuracy was assessed with the area under the curve (AUC) of receiver operating characteristics (ROC) plots, sensitivity and specificity. Relationships between each measure of accuracy and species ecological characteristics were then examined. SDMs of the fish species presented small differences between the considered scales, and predictors as latitude, temperature and salinity were often selected at both scales. Measures of model accuracy presented differences between species and scales, but generally higher accuracy was obtained at smaller spatial scales. Among the ecological traits tested, species feeding mode and estuarine use functional groups were the most influential on the performance of distribution models. Habitat tolerance (number of habitat types frequented), species abundance, body size and spawning period also showed some effect. This analyses will contribute to distinguish, based on species

  8. Species and prevalence determination of Human Intestinal ...

    African Journals Online (AJOL)

    ADOWIE PERE

    Species and prevalence determination of Human Intestinal Parasites among Patients attending two ... the maintenance of proper personal hygiene, creating awareness to the ..... (2007), who reported a value of 21.1% in Owerri,. Imo State and ...

  9. Metabolomic analysis of three Mollicute species.

    Directory of Open Access Journals (Sweden)

    Anna A Vanyushkina

    Full Text Available We present a systematic study of three bacterial species that belong to the class Mollicutes, the smallest and simplest bacteria, Spiroplasma melliferum, Mycoplasma gallisepticum, and Acholeplasma laidlawii. To understand the difference in the basic principles of metabolism regulation and adaptation to environmental conditions in the three species, we analyzed the metabolome of these bacteria. Metabolic pathways were reconstructed using the proteogenomic annotation data provided by our lab. The results of metabolome, proteome and genome profiling suggest a fundamental difference in the adaptation of the three closely related Mollicute species to stress conditions. As the transaldolase is not annotated in Mollicutes, we propose variants of the pentose phosphate pathway catalyzed by annotated enzymes for three species. For metabolite detection we employed high performance liquid chromatography coupled with mass spectrometry. We used liquid chromatography method - hydrophilic interaction chromatography with silica column - as it effectively separates highly polar cellular metabolites prior to their detection by mass spectrometer.

  10. Camas - Invasive Species Management with Refuge Volunteers

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — In the past Camas NWR has focused on mapping and treating only Russian knapweed and swainsonpea. We have other species present in lower numbers and quite possibly...

  11. New species in Aspergillus section Terrei

    DEFF Research Database (Denmark)

    Samson, R. A.; Peterson, S. W.; Frisvad, Jens Christian

    2011-01-01

    Section Terrei of Aspergillus was studied using a polyphasic approach including sequence analysis of parts of the beta-tubulin and calmodulin genes and the ITS region, macro- and micromorphological analyses and examination of extrolite profiles to describe three new species in this section. Based...... on phylogenetic analysis of calmodulin and beta-tubulin sequences seven lineages were observed among isolates that have previously been treated as A. terreus and its subspecies by Raper & Fennell (1965) and others. Aspergillus alabamensis, A. terreus var. floccosus, A. terreus var. africanus, A. terreus var....... floccosus, A. terreus var. africanus, A. terreus var. aureus, while Aspergillus hortai is recognised at species level. Aspergillus terreus NRRL 4017 is described as the new species A. pseudoterreus. Also included in section Terrei are some species formerly placed in sections Flavipedes and Versicolores. A...

  12. Luminescence properties of uranyl-acetate species

    Energy Technology Data Exchange (ETDEWEB)

    Brinkmann, Hannes; Moll, Henry [Helmholtz-Zentrum Dresden-Rossendorf e.V., Dresden (Germany). Inst. of Resource Ecology; Stumpf, Thorsten [Helmholtz-Zentrum Dresden-Rossendorf e.V., Dresden (Germany). Biogeochemistry

    2017-06-01

    Time-resolved laser-induced fluorescence spectroscopy (TRLFS) was applied to characterize uranium(VI)- acetate species based on their luminescence properties. In contrast to previous interpretations, no indications were detected for the existence of the 1: 3 complex.

  13. Germplasm characterization of three jabuticaba tree species

    Directory of Open Access Journals (Sweden)

    Moeses Andrigo Danner

    2011-09-01

    Full Text Available The purpose of this study was to characterize cultivated genotypes of three jabuticaba species (Plinia cauliflora, P. trunciflora, and P. jaboticaba. Phenology and fruit growth, as well as leaf, flower and fruit traits were evaluated. Variability in all traits was observed among genotypes of the three jabuticaba species. The trait peduncle size is indicated for differentiation of the three species under study. The leaf and fruit sizes of the genotypes P. trunciflora 3, P. trunciflora 4, P. trunciflora 5 and P. jaboticaba 1 differ from those described in the literature for these species, indicating the formation of ecotypes. Jabuticaba fruit skin contains high anthocyanin and flavonoid concentrations, with potential use in food and pharmaceutical industries.

  14. Functional Diversification within a Predatory Species Flock

    Science.gov (United States)

    Burress, Edward D.; Duarte, Alejandro; Serra, Wilson S.; Loueiro, Marcelo; Gangloff, Michael M.; Siefferman, Lynn

    2013-01-01

    Ecological speciation is well-known from adaptive radiations in cichlid fishes inhabiting lentic ecosystems throughout the African rift valley and Central America. Here, we investigate the ecological and morphological diversification of a recently discovered lotic predatory Neotropical cichlid species flock in subtropical South America. We document morphological and functional diversification using geometric morphometrics, stable C and N isotopes, stomach contents and character evolution. This species flock displays species-specific diets and skull and pharyngeal jaw morphology. Moreover, this lineage appears to have independently evolved away from piscivory multiple times and derived forms are highly specialized morphologically and functionally relative to ancestral states. Ecological speciation played a fundamental role in this radiation and our data reveal novel conditions of ecological speciation including a species flock that evolved: 1) in a piscivorous lineage, 2) under lotic conditions and 3) with pronounced morphological novelties, including hypertrophied lips that appear to have evolved rapidly. PMID:24278349

  15. Density of Threatened and Endangered Species

    Data.gov (United States)

    California Department of Resources — A compiled density of threatened and endangered species built around 2000m wide hexagonal cells. The dataset was created by generating a blank hex grid, intersecting...

  16. Nonindigenous Aquatic Species Database Marine Fishes

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The Nonindigenous Aquatic Species Database (NAS) information resource is an established central repository for spatially referenced biogeographic accounts of...

  17. Inferring species decline from collection records

    DEFF Research Database (Denmark)

    Carpaneto, Giuseppe Maria; Mazziotta, Adriano; Valerio, Laura

    2007-01-01

    The decline of roller dung beetles (Coleoptera, Scarabaeidae) in Italy, at national and regional level, was described using a database of both literature and unpublished data, since the late of 19th century. The probability of finding roller species was assessed for each decade of the 20th century...... UTM cells dropped by 23%. Six roller species showed a significant decline in Italy from the first to the second part of the 20th century, and nine in the last 30years. Other two species disappeared from the majority of the northern regions. Finally, the values of all the extinction indexes were...... strongly correlated and detected a high risk of extinction in Italy for six species. A gradual change in land use during the last three decades, consisting of a reduced extension of grasslands in favour of either intensive agriculture or reforestation after abandonment of livestock raising, was likely...

  18. Recent advances and new species in aquaculture

    National Research Council Canada - National Science Library

    Fotedar, Ravi K; Phillips, Bruce F

    2011-01-01

    .... More specifically, you will find information on the culture of species such as barramundi, cobia, dolphin fish, spiny lobsters, slipper lobsters, mud crabs, penaeid prawns, Nile tilapia, yellow king...

  19. On the Origins of a Vibrio species

    DEFF Research Database (Denmark)

    Vesth, Tammi Camilla; Wassenaar, Gertrude Maria; Hallin, Peter Fischer;

    2010-01-01

    Thirty-two genome sequences of various Vibrionaceae members are compared, with emphasis on what makes V. cholerae unique. As few as 1,000 gene families are conserved across all the Vibrionaceae genomes analysed; this fraction roughly doubles for gene families conserved within the species V....... cholerae. Of these, approximately 200 gene families that cluster on various locations of the genome are not found in other sequenced Vibrionaceae; these are possibly unique to the V. cholerae species. By comparing gene family content of the analysed genomes, the relatedness to a particular species...... is identified for two unspeciated genomes. Conversely, two genomes presumably belonging to the same species have suspiciously dissimilar gene family content. We are able to identify a number of genes that are conserved in, and unique to, V. cholerae. Some of these genes may be crucial to the niche adaptation...

  20. A Single Species Model with Impulsive Diffusion

    Institute of Scientific and Technical Information of China (English)

    Jing Hui; Lan-sun Chen

    2005-01-01

    In most models of population dynamics, diffusion between patches is assumed to be continuous or discrete, but in practice many species diffuse only during a single period. In this paper we propose a single species model with impulsive diffusion between two patches, which provides a more natural description of population dynamics. By using the discrete dynamical system generated by a monotone, concave map for the population,we prove that the map alwayshas a globally stable positive fixed point. This means that a single species system with impulsive diffusion always has a globally stable positive periodic solution. This result is further substantiated by numerical simulation. Under impulsive diffusion the single species survives in the two patches.

  1. The Grolier World Encyclopedia of Endangered Species.

    Science.gov (United States)

    Martin, Ron

    1994-01-01

    Reviews "The Grolier World Encyclopedia of Endangered Species" and describes a lesson plan for grades five and six that includes library media skills objectives, science objectives, resources, instructional roles, activity and procedure for completion, evaluation, and follow-up. (LRW)

  2. Palmyra Atoll - Invasive Species Management 2008

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — We initiated management of 3 species of plants that are introduced and invasive at Palmyra Atoll NWR. The work consisted of describing the distributions of these...

  3. Molecular characterization of Eimeria species in macropods.

    Science.gov (United States)

    Yang, Rongchang; Fenwick, Stan; Potter, Abbey; Elliot, Aileen; Power, Michelle; Beveridge, Ian; Ryan, Una

    2012-10-01

    A total of 597 faecal samples were collected from western grey kangaroos (Macropus fuliginosus), Euros (M. robustus), red kangaroos (M. rufus) in Western Australia and Eastern Grey Kangaroos (M. giganteus) from Victoria and screened for the presence of Eimeria by PCR at the 18S ribosomal RNA (rRNA) locus. The overall prevalence was 24.3% (145/597). At the 18S rRNA locus, sequences were obtained for 25 of the 145 positives. Phylogenetic analysis indicated that all the macropod-derived Eimeria species grouped in a separate marsupial clade that included Eimeria trichosuri from brushtail possums. At least 6 different clades were identified within the marsupial isolates and many of the genotypes identified are likely to be valid species, however morphological and biological data need to be collected to match sequences to previously characterized Eimeria species or identify if they are new species.

  4. Virulence of Fusarium species to alfalfa seedlings

    Directory of Open Access Journals (Sweden)

    Krnjaja Vesna

    2005-01-01

    Full Text Available In in vitro conditions, virulence of 91 isolates of species Fusarium genus (F. oxysporum, F. solani, F. acuminatum, F. equiseti, F. arthrosporioides, F. prolifera- tum, F. avenaceum, F. semitectum, F. tricinctum, F. sporotrichioides and F. graminearum towards alfalfa seedlings was investigated. Isolates of investigated species originated from diseased alfalfa plants collected at four locations in Serbia based on symptoms of wilting caused by Fusarium and root rotting. Pathogenicity and virulence of investigated isolates of Fusarium spp. were determined by visual evaluation of inoculated seedlings of cultivar K28 in laboratory conditions. All isolated of investigated species had pathogenic effect on alfalfa seedlings which expressed symptoms such as necrosis of root, moist rotting and "melting of seedlings". Colour of necrotic root tissue varied from light brown, brown lipstick red to explicit black, depending on the Fusarium species. Strong virulence was established in 48 isolates, medium virulence in 31 and weak virulence in 12 isolates.

  5. Influence of estuaries on shelf foraminiferal species

    Digital Repository Service at National Institute of Oceanography (India)

    Nigam, R.

    Dabhol-bhatkal stretch of the west coast of India is marked by a number of estuaries. Cavarotalia annectens is selected to monitor the influence of these estuaries on the inner shelf foraminiferal fauna. The percentage distribution of this species...

  6. Inferring species decline from collection records

    DEFF Research Database (Denmark)

    Carpaneto, Giuseppe Maria; Mazziotta, Adriano; Valerio, Laura

    2007-01-01

    increased clearly as a consequence of the escalation of entomological surveys. Nevertheless, comparing R species (rollers) with all the scarab dung beetles from the first to the last quarter of the 20th century, the relative frequency of roller records decreased by 31%, while the relative number of occupied......The decline of roller dung beetles (Coleoptera, Scarabaeidae) in Italy, at national and regional level, was described using a database of both literature and unpublished data, since the late of 19th century. The probability of finding roller species was assessed for each decade of the 20th century...... UTM cells dropped by 23%. Six roller species showed a significant decline in Italy from the first to the second part of the 20th century, and nine in the last 30years. Other two species disappeared from the majority of the northern regions. Finally, the values of all the extinction indexes were...

  7. Virulence of Fusarium species to alfalfa seedlings

    Directory of Open Access Journals (Sweden)

    Krnjaja Vesna

    2005-01-01

    Full Text Available In in vitro conditions, virulence of 91 isolates of species Fusarium genus (F. oxysporum, F. solani, F. acuminatum, F. equiseti, F. arthrosporioides, F. proliferatum, F. avenaceum, F. semitectum, F. tricinctum, F. sporotrichioides and F. graminearum towards alfalfa seedlings was investigated. Isolates of investigated species originated from diseased alfalfa plants collected on four locations in Serbia based on symptoms of wilting caused by fusarium and root rotting. Pathogenicity and virulence of investigated isolates of Fusarium spp. were determined by visual evaluation of inoculated seedlings of cultivars K28 in laboratory conditions. All isolated of investigated species had pathogenic effect on alfalfa seedlings, which expressed symptoms such as necrosis of root, moist rotting and "melting of seedlings". Colour of necrotic root tissue varied from light brown, brown, lipstick red to explicit black, depending on the Fusarium species. Strong virulence was established in 48 isolates, medium virulence in 31 and weak virulence in 12 isolates.

  8. Detection of Campylobacter species using monoclonal antibodies

    Science.gov (United States)

    Young, Colin R.; Lee, Alice; Stanker, Larry H.

    1999-01-01

    A panel of species specific monoclonal antibodies were raised to Campylobacter coli, Campylobacter jejuni and Campylobacter lari. The isotypes, and cross-reactivity profiles of each monoclonal antibody against an extensive panel of micro- organisms, were determined.

  9. CLIMBING BEHAVIOUR IN THREE AFRICAN RODENT SPECIES ...

    African Journals Online (AJOL)

    Two Saccostomus came from the Kalahari Gemsbok National Park and one from the ..... Of the three species tested, Thallomys shows the best psychological and ... The biology and behaviour of a free living population of black rats (Rattus.

  10. Species Assortment and Biodiversity Conservation in Homegardens ...

    African Journals Online (AJOL)

    user

    mature gardens housing moderate level of species richness. Putting all perennial ..... access to exotic planting materials as they are often available in the market. Table 4. Relative and ..... The University of Melbourne. Mckinney M.L. 2002.

  11. Global minimizers of coexistence for competing species

    OpenAIRE

    2010-01-01

    A class of variational models describing ecological systems of k species competing for the same resources is investigated. The occurrence of coexistence in minimal energy solutions is discussed and positive results are proven for suitably differentiated internal dynamics.

  12. On two new species of Siriella (Mysidacea)

    Digital Repository Service at National Institute of Oceanography (India)

    Panampunnayil, S.U.

    Descriptions of two new mysids, Siriella africana ap. nov. collected from Agulhas Bank and S. intermedia sp. nov. collected from Laccadives are given. The present paper contains observations on two species of mysidacea collected from the Indian...

  13. Tree Species Identity Shapes Earthworm Communities

    DEFF Research Database (Denmark)

    Schelfhout, Stephanie; Mertens, Jan; Verheyen, Kris

    2017-01-01

    Earthworms are key organisms in forest ecosystems because they incorporate organic material into the soil and affect the activity of other soil organisms. Here, we investigated how tree species affect earthworm communities via litter and soil characteristics. In a 36-year old common garden...... experiment, replicated six times over Denmark, six tree species were planted in blocks: sycamore maple (Acer pseudoplatanus), beech (Fagus sylvatica), ash (Fraxinus excelsior), Norway spruce (Picea abies), pedunculate oak (Quercus robur) and lime (Tilia cordata). We studied the chemical characteristics...... of soil and foliar litter, and determined the forest floor turnover rate and the density and biomass of the earthworm species occurring in the stands. Tree species significantly affected earthworm communities via leaf litter and/or soil characteristics. Anecic earthworms were abundant under Fraxinus, Acer...

  14. CONSERVATION METHODS OF ENDANGERED SPECIES GUNDU ...

    African Journals Online (AJOL)

    user

    conservation measure, an endangered species finally goes into extinction, that is, permanent disappearance from the earth ... plants or animal outside of its natural habitat either by removing ..... Northern States on the danger List.The. National ...

  15. Traditional uses of indigenous tree species

    African Journals Online (AJOL)

    Mo

    extinction. It is thus important to promote sustainable management and use of Uganda's indigenous tree species ... Except for picking, the rest of the methods used during harvesting are destructive to the entire plant. ... Thus there is a danger of.

  16. ESUSA: US endangered species distribution file

    Energy Technology Data Exchange (ETDEWEB)

    Nagy, J.; Calef, C.E.

    1979-10-01

    This report describes a file containing distribution data on endangered species of the United States of Federal concern pursuant to the Endangered Species Act of 1973. Included for each species are (a) the common name, (b) the scientific name, (c) the family, (d) the group (mammal, bird, etc.), (e) Fish and Wildlife Service (FWS) listing and recovery priorities, (f) the Federal legal status, (g) the geographic distribution by counties or islands, (h) Federal Register citations and (i) the sources of the information on distribution of the species. Status types are endangered, threatened, proposed, formally under review, candidate, deleted, and rejected. Distribution is by Federal Information Processing Standard (FIPS) county code and is of four types: designated critical habitat, present range, potential range, and historic range.

  17. How many species have mass M?

    CERN Document Server

    Clauset, Aaron; Redner, Sidney

    2008-01-01

    Within large taxonomic assemblages, the number of species with adult body mass M is characterized by a broad but asymmetric distribution, with the largest mass being orders of magnitude larger than the typical mass. This canonical shape can be explained by cladogenetic diffusion that is bounded below by a hard limit on viable species mass and above by extinction risks that increase weakly with mass. Here we introduce and analytically solve a simplified cladogenetic diffusion model. When appropriately parameterized, the diffusion-reaction equation predicts mass distributions that are in good agreement with data on 4002 terrestrial mammal from the late Quaternary and 8617 extant bird species. Under this model, we show that a specific tradeoff between the strength of within-lineage drift toward larger masses (Cope's rule) and the increased risk of extinction from increased mass is necessary to produce realistic mass distributions for both taxa. We then make several predictions about the evolution of avian specie...

  18. 75 FR 29359 - Invasive Species Advisory Committee

    Science.gov (United States)

    2010-05-25

    ... complex relationship between climate change and invasive species, opportunities for green jobs creation... Argonaut Hotel, 495 Jefferson Street at Hyde, San Francisco, California 94109-1314. The general session on...

  19. Alabama's many endangered aquatic species are unprotected

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Newspaper article on the vulnerability of watercress darter and other fish species in Alabama after a significant fish kill in Roebuck Spring pond in 2008.

  20. Distribution maps for Midsouth tree species

    Science.gov (United States)

    Roy C. Beltz; Daniel F. Bertelson

    1990-01-01

    The Midsouth is an important timber-producing region, with a wide variety of sites and species. In addition to timber production, increasing demands for non-timber amenities are placed on the region’s forests. These maps indicate the distribution of individual species recorded in surveys of the Midsouth conducted by the U.S. Department of Agriculture, Forest Service....

  1. Effect of Landscape Structure on Species Diversity.

    Directory of Open Access Journals (Sweden)

    Paulo R A Campos

    Full Text Available The effects of habitat fragmentation and their implications for biodiversity is a central issue in conservation biology which still lacks an overall comprehension. There is not yet a clear consensus on how to quantify fragmentation even though it is quite common to couple the effects of habitat loss with habitat fragmentation on biodiversity. Here we address the spatial patterns of species distribution in fragmented landscapes, assuming a neutral community model. To build up the fragmented landscapes, we employ the fractional Brownian motion approach, which in turn permits us to tune the amount of habitat loss and degree of clumping of the landscape independently. The coupling between the neutral community model, here simulated by means of the coalescent method, and fractal neutral landscape models enables us to address how the species-area relationship changes as the spatial patterns of a landscape is varied. The species-area relationship is one of the most fundamental laws in ecology, considered as a central tool in conservation biology, and is used to predict species loss following habitat disturbances. Our simulation results indicate that the level of clumping has a major role in shaping the species-area relationship. For instance, more compact landscapes are more sensitive to the effects of habitat loss and speciation rate. Besides, the level of clumping determines the existence and extension of the power-law regime which is expected to hold at intermediate scales. The distributions of species abundance are strongly influenced by the degree of fragmentation. We also show that the first and second commonest species have approximately self-similar spatial distributions across scales, with the fractal dimensions of the support of the first and second commonest species being very robust to changes in the spatial patterns of the landscape.

  2. Physiological and Growth Characteristics of Shewanella Species

    Science.gov (United States)

    2016-05-01

    282–287. 29. Dawood B. 1998. Corrosion-enhancing potential of Shewanella putrefaciens isolated from industrial cooling waters. J Appl Microbiol. 84...AFCEC-CX-TY-TR-2016-0016 PHYSIOLOGICAL AND GROWTH CHARACTERISTICS OF SHEWANELLA SPECIES Karen Farrington, D. Matthew Eby, Susan Sizemore...Technical Report 01 March 2012 - 01 March 2014 Physiological and growth characteristics of Shewanella species FA4819-11-C-0003 Karen Farrington (1

  3. Anaplasma species of veterinary importance in Japan

    OpenAIRE

    Adrian Patalinghug Ybañez; Hisashi Inokuma

    2016-01-01

    Anaplasma species of the family Anaplasmataceae, order Rickettsiales are tick-borne organisms that can cause disease in animals and humans. In Japan, all recognized species of Anaplasma (except for Anaplasma ovis) and a potentially novel Anaplasma sp. closely related to Anaplasma phagocytophilum have been reported. Most of these detected tick-borne pathogens are believed to be lowly pathogenic in animals in Japan although the zoonotic A. phagocytophilum has recently been reported to cause cli...

  4. The ethics of reviving long extinct species.

    Science.gov (United States)

    Sandler, Ronald

    2014-04-01

    There now appears to be a plausible pathway for reviving species that have been extinct for several decades, centuries, or even millennia. I conducted an ethical analysis of de-extinction of long extinct species. I assessed several possible ethical considerations in favor of pursuing de-extinction: that it is a matter of justice; that it would reestablish lost value; that it would create new value; and that society needs it as a conservation last resort. I also assessed several possible ethical arguments against pursuing de-extinction: that it is unnatural; that it could cause animal suffering; that it could be ecologically problematic or detrimental to human health; and that it is hubristic. There are reasons in favor of reviving long extinct species, and it can be ethically acceptable to do so. However, the reasons in favor of pursuing de-extinction do not have to do with its usefulness in species conservation; rather, they concern the status of revived species as scientific and technological achievements, and it would be ethically problematic to promote de-extinction as a significant conservation strategy, because it does not prevent species extinctions, does not address the causes of extinction, and could be detrimental to some species conservation efforts. Moreover, humanity does not have a responsibility or obligation to pursue de-extinction of long extinct species, and reviving them does not address any urgent problem. Therefore, legitimate ecological, political, animal welfare, legal, or human health concerns associated with a de-extinction (and reintroduction) must be thoroughly addressed for it to be ethically acceptable. © 2013 Society for Conservation Biology.

  5. FISHy Analysis of Tetraploid Cotton Species

    Institute of Scientific and Technical Information of China (English)

    STELLY; David

    2008-01-01

    Fluorescent in situ hybridization(FISH) is an important technique in plant genome research,because it provides integrated information about DNA,chromosomes and genomes.Genomic in situ hybridization(GISH) is a modification of FISH that can be used to rapidly compare genome content,relatedness,organization and/or behavior.GISH results often provide insight into genome evolution and species relationships.The cotton genus Gossypium consists of about 50 species,including 5 AADD

  6. Reservoirs of Non-baumannii Acinetobacter Species

    OpenAIRE

    Ahmad eAl Atrouni; Monzer eHamze; Marie-Laure eJoly-Guillou; Marie eKEMPF

    2016-01-01

    Acinetobacter spp. are ubiquitous gram negative and non-fermenting coccobacilli that have the ability to occupy several ecological niches including environment, animals and human. Among the different species, Acinetobacter baumannii has evolved as global pathogen causing wide range of infection. Since the implementation of molecular techniques, the habitat and the role of non-baumannii Acinetobacter in human infection have been elucidated. In addition, several new species have been described....

  7. Transvalued species in an African forest.

    Science.gov (United States)

    Remis, Melissa J; Hardin, Rebecca

    2009-12-01

    We combined ethnographic investigations with repeated ecological transect surveys in the Dzanga-Sangha Dense Forest Reserve (RDS), Central African Republic, to elucidate consequences of intensifying mixed use of forests. We devised a framework for transvaluation of wildlife species, which means the valuing of species on the basis of their ecological, economic, and symbolic roles in human lives. We measured responses to hunting, tourism, and conservation of two transvalued species in RDS: elephants (Loxodonta cyclotis) and gorillas (Gorilla gorilla). Our methods included collecting data on encounter rates and habitat use on line transects. We recorded cross-cultural variation in ideas about and interactions with these species during participant observation of hunting and tourism encounters and ethnographic interviews with hunters, conservation staff, researchers, and tourists. Ecologically, gorillas used human-modified landscapes successfully, and elephants were more vulnerable than gorillas to hunting. Economically, tourism and encounters with elephants and gorillas generated revenues and other benefits for local participants. Symbolically, transvaluation of species seemed to undergird competing institutions of forest management that could prove unsustainable. Nevertheless, transvaluation may also offer alternatives to existing social hierarchies, thereby integrating local and transnational support for conservation measures. The study of transvaluation requires attention to transnational flows of ideas and resources because they influence transspecies interactions. Cross-disciplinary in nature, transvalution of species addresses the political and economic challenges to conservation because it recognizes the varied human communities that shape the survival of wildlife in a given site. Transvaluation of species could foster more socially inclusive management and monitoring approaches attuned to competing economic demands, specific species behaviors, and human

  8. Supercritical fluid extraction of mercury species.

    Science.gov (United States)

    Foy, G P; Pacey, G E

    2003-12-23

    Supercritical fluid extraction was used to recover organic and inorganic mercury species. Variations in pressure, water, methanol, and chelator create methods that allowed separation of inorganic from organic mercury species. When extracted using a compromised set of extraction conditions, the order of extraction was methyl, phenyl and inorganic mercury. For the individually optimized conditions, quantitative recoveries were observed. Level as low as 20 ppb were extracted and then determined using ICP.

  9. Pollen characteristics in some Diospyros species

    Directory of Open Access Journals (Sweden)

    Olga Grygorieva

    2013-04-01

    Full Text Available Aim of the work was to study the general characteristics and essential morphological traits of pollen grains viz the size, shape of pollen grains and number, form and position of apertures in Diospyros kaki L.f., D. virginiana L., D. lotus L. species and interspecies hybrid of D. virginiana × D. kaki. Significant differences were detected among the tested species and the interspecific hybrid as well as between individual genotypes of D. lotus , especially in the equatorial axis.

  10. Isoprene emission from tropical tree species

    Energy Technology Data Exchange (ETDEWEB)

    Padhy, P.K. [School of Environmental Sciences, Jawaharlal Nehru University, New Delhi 110 067 (India)]. E-mail: padhypk2003@yahoo.com; Varshney, C.K. [School of Environmental Sciences, Jawaharlal Nehru University, New Delhi 110 067 (India)

    2005-05-01

    Foliar emission of isoprene was measured in nine commonly growing tree species of Delhi, India. Dynamic flow enclosure technique was used and gas samples were collected onto Tenax-GC/Carboseive cartridges, which were then attached to the sample injection system in the gas chromatograph (GC). Eluting compounds were analysed using a flame ionisation detector (FID). Out of the nine tree species, isoprene emission was found in six species (Eucalyptus sp., Ficus benghalensis, Ficus religiosa, Mangifera indica, Melia azedarach, and Syzygium jambolanum), whereas, in the remaining three tree species (Alstonia scholaris, Azadirachta indica, and Cassia fistula) no isoprene emission was detected or the levels of emission were negligible or below the detection limit (BDL). Among six tree species, the highest hourly emission (10.2{+-}6.8 {mu}g g{sup -1} leaf dry weight, average of five seasons) was observed in Ficus religiosa, while minimum emission was from Melia azedarach (2.2{+-}4.9 {mu}g g{sup -1} leaf dry weight, average of five seasons). Isoprene emission (average of six species), over five seasons, was found to vary between 3.9 and 8.5 {mu}g g{sup -1} leaf dry weight during the rainy season. In addition, significant diurnal variation in isoprene emission was observed in each species. The preliminary estimate made in this study on the annual biogenic VOC emission from India may probably be the first of its kind from this part of the world. - Isoprene flux (diurnal and seasonal) from some tropical tree species was estimated and a regional comparison was made.

  11. Relation of chironomids with Aeromonas species

    Directory of Open Access Journals (Sweden)

    Sivan eLaviad

    2016-05-01

    Full Text Available Chironomids (Diptera: Chironomidae, also known as non-biting midges, are one of the most abundant groups of insects in aquatic habitats. They undergo a complete metamorphosis of four life stages of which three are aquatic (egg, larva, pupa, and the adult emerges into the air. Chironomids serve as a natural reservoir of Aeromonas and Vibrio cholerae species. Here we review existing knowledge about the mutual relations between Aeromonas species and chironomids. Using 454-pyrosequencing of the 16S rRNA gene, we found that the prevalence of Aeromonas species in the insects’ egg masses and larvae was 1.6% and 3.3% of the insects’ endogenous microbiota, respectively. Aeromonas abundance per egg mass remained stable during a six-month period of bacterial monitoring. Different Aeromonas species were isolated and some demonstrated the ability to degrade the insect’s egg masses and to prevent eggs hatching. Chitinase was identified as the enzyme responsible for the egg mass degradation. Different Aeromonas species isolated from chironomids demonstrated the potential to protect their host from toxic metals. Aeromonas is a causative agent of fish infections. Fish are frequently recorded as feeding on chironomids. Thus, fish might be infected with Aeromonas species via chironomid consumption. Aeromonas strains are also responsible for causing gastroenteritis and wound infections in humans. Different virulence genes were identified in Aeromonas species isolated from chironomids. Chironomids may infest drinking water reservoirs, hence be the source of pathogenic Aeromonas strains in drinking water. Chironomids and Aeromonas species have a complicated mutual relationship.

  12. The South African species of Hemizygia (Lamiaceae

    Directory of Open Access Journals (Sweden)

    L. E. Codd

    1976-12-01

    Full Text Available The South African species of Hemizygia are reviewed and 28 species are recognized, including the following new names:  H. macrophylla (Guerke Codd (=Syncolostemon macrophyllus Guerke,  H. pretoriae Guerke var. heterotricha Codd,  H. cinerea Codd,  H. incana Codd,  H. modesta Codd, H. parvifolia Codd, H. punctata Codd and  H. ramosa Codd.

  13. Rosacea, Reactive Oxygen Species, and Azelaic Acid

    OpenAIRE

    David A. Jones

    2009-01-01

    Rosacea is a common skin condition thought to be primarily an inflammatory disorder. Neutrophils, in particular, have been implicated in the inflammation associated with rosacea and mediate many of their effects through the release of reactive oxygen species. Recently, the role of reactive oxygen species in the pathophysiology of rosacea has been recognized. Many effective agents for rosacea, including topical azelaic acid and topical metronidazole, have anti-inflammatory properties. in-vitro...

  14. Comparative wood anatomy of Rhodothamnus species

    OpenAIRE

    SERDAR, Bedri

    2014-01-01

    In this study, the comparative wood anatomy of the European [Rhodothamnus chamaecistus (L.) Reichb.] and Anatolian (Rhodothamnus sessilifolius P.H.Davis) species of Rhodothamnus were studied. The wood anatomy of the taxa shows evidence of adaptation to growing in alpine habitats. The woods of the species exhibit primitive wood anatomical characteristics and share similar qualitative anatomical features. However, some of the quantitative anatomical characteristics of the taxa show significant ...

  15. Invasive Species - A Threat to the Homeland?

    Science.gov (United States)

    2003-04-07

    species of weeds, diseases and organisms on both my farm and the surrounding woodlands. Some of these species include soybean cyst nematode , soybean aphid...many of the chemicals used to control unwanted plants and even make them resistant to some natural biologic insect controls – thereby making the...such as fencing), and release of biological control agents, pesticides, and cultural practices. In addition, Executive Order 13112 requires

  16. Phytochemistry and Pharmacology of Berberis Species

    Directory of Open Access Journals (Sweden)

    Najmeh Mokhber-Dezfuli

    2014-01-01

    Full Text Available The genus Berberis (Berberidaceae includes about 500 species worldwide, some of which are widely cultivated in the north-eastern regions of Iran. This genus consists of spiny deciduous evergreen shrubs, characterized by yellow wood and flowers. The cultivation of seedless barberry in South Khorasan goes back to two hundred years ago. Medicinal properties for all parts of these plants have been reported, including: Antimicrobial, antiemetic, antipyretic, antioxidant, anti-inflammatory, anti-arrhythmic, sedative, anti-cholinergic, cholagogic, anti-leishmaniasis, and anti-malaria. The main compounds found in various species of Berberis, are berberine and berbamine. Phytochemical analysis of various species of this genus revealed the presence of alkaloids, tannins, phenolic compounds, sterols and triterpenes. Although there are some review articles on Berberis vulgaris (as the most applied species, there is no review on the phytochemical and pharmacological activities of other well-known species of the genus Berberis. For this reason, the present review mainly focused on the diverse secondary metabolites of various species of this genus and the considerable pharmacological and biological activities together with a concise story of the botany and cultivation.

  17. Transient Species in Plasmas Interacting with Liquids

    Science.gov (United States)

    Reuter, S.; Schmidt-Bleker, A.; van Helden, J. H.; Jablonowski, H.; Winter, J.; Santos Sousa, J.; Gianella, M.; Ritchie, G.; Weltmann, K.-D.

    2016-09-01

    Processes of non-equilibrium plasmas at gas-liquid interfaces are determined by transient species. Quantification of these species in the plasma, gas, or liquid is intricate and requires specific diagnostics. In order to study plasma-liquid interaction processes, novel diagnostic concepts need to be developed combined with simulations that allow an insight into the chemical reaction pathways. Significantly relevant transient species in plasmas operated in ambient air include HO2 and O2(a1 Δ) , which are diagnosed in this work. The aim is to link localized transient species with longer living stable species in the gas phase and in the liquid phase. Understanding reaction pathways makes it possible to control the reactive species composition generated by the cold plasmas, and further insight into plasma induced reactivity in condensed matter systems can be gained. The work shows a combination of absorption spectroscopic methods and other diagnostic techniques as well as simple kinetics modeling as a way to control the plasma chemical reactions.

  18. Inducible clindamycin resistance in Staphylococcus species.

    Science.gov (United States)

    Afridi, Faisal Iqbal; Zeb, Mubarak; Hussain, Arif; Farooqi, Badar Jahan; Murtuza, Ghulam

    2014-07-01

    To determine the frequency of inducible clindamycin resistance in clinical isolates of Staphylococcus species by phenotypic D-test. Observational study. Ziauddin University Hospital, Karachi, from July to December 2011. Consecutive clinical isolates of Staphylococcus species were collected and identified by conventional microbiological techniques. Antimicrobial susceptibility testing and inducible clindamycin resistance was carried out by performing D-test using CLSI criteria. Methicillin resistance was detected by using Cefoxitin disk as a surrogate marker. Statistical analysis was performed by SPSS version-17. A total of 667 clinical isolates of Staphylococcus species were obtained during the study period. In these isolates, 177 (26.5%) were Staphylococcus aureus, and 490 (73.5%) were coagulase negative Staphylococci. The total frequency of inducible clindamycin resistance among isolates of Staphylococcus species was 120/667 (18%). Frequency of inducible clindamycin resistance among coagulase negative Staphylococci group and Staphylococcus aureus group were 18.57% and 16.38% respectively. Median age of patients in D-test positive group was 19.5 (1 - 54) years. The frequency of inducible clindamycin resistance among Staphylococcus species may differ in different hospital setup. Clinical microbiology laboratories should implement testing simple and effective D-test on all Staphylococcus species. D-test positive isolates should be reported clindamycin resistant to decrease treatment failure.

  19. Rare species are valued big time.

    Directory of Open Access Journals (Sweden)

    Elena Angulo

    Full Text Available BACKGROUND: It has recently been postulated that the value humans place on rarity could cause the extinction of rare species. This is because people are willing to pay the high costs of exploiting the last individuals. Many hobbies, such as ecotourism or the keeping of exotic pets may cause this effect--known as the anthropogenic Allee effect. However, the entire theory relies on the insofar undemonstrated assumption that people do value rarity. METHODOLOGY/PRINCIPAL FINDINGS: In order to quantify how much people valued rare species relative to common ones, we created online slideshows of photographs of either rare or common species on an Internet web site. The slideshow with photographs of rare species attracted more visitors, and visitors spent, in general, more time waiting to view it. CONCLUSIONS/SIGNIFICANCE: We provide evidence that people value rare more than common species. As we did not target consumers of a specific market, this finding suggests that the anthropogenic Allee effect is likely be driven by a large part of the population. Given the substantial participation in our online experiment, we highlight the potential of the world wide web resource as a tool for conservation action. However, the evidence presented here that the general public value rare species, combined with the assumption that anthropogenic Allee effect is operating, implies that conservationists should be prudent when using rarity to promote conservation.

  20. The art and science of species delimitation

    Institute of Scientific and Technical Information of China (English)

    Bruce RANNALA

    2015-01-01

    DNA-based approaches to systematics have changed dramatically during the last two decades with the rise of DNA barcoding methods and newer multi-locus methods for species delimitation. During the last half-decade, partly driven by the new sequencing technologies, the focus has shifted to multi-locus sequence data and the identification of species within the frame-work of the multi-species coalescent (MSC). In this paper, I discuss model-based Bayesian methods for species delimitation that have been developed in recent years using the MSC. Several approximate methods for species delimitation (and their limitations) are also discussed. Explicit species delimitation models have the advantage of clarifying more precisely what is being delimited and what assumptions we are making in doing so. Moreover, the methods can be very powerful when applied to large multi-locus datasets and thus take full advantage of data generated using today’s technologies [Current Zoology 61 (5): 846–853, 2015].

  1. Global threat to agriculture from invasive species.

    Science.gov (United States)

    Paini, Dean R; Sheppard, Andy W; Cook, David C; De Barro, Paul J; Worner, Susan P; Thomas, Matthew B

    2016-07-05

    Invasive species present significant threats to global agriculture, although how the magnitude and distribution of the threats vary between countries and regions remains unclear. Here, we present an analysis of almost 1,300 known invasive insect pests and pathogens, calculating the total potential cost of these species invading each of 124 countries of the world, as well as determining which countries present the greatest threat to the rest of the world given their trading partners and incumbent pool of invasive species. We find that countries vary in terms of potential threat from invasive species and also their role as potential sources, with apparently similar countries sometimes varying markedly depending on specifics of agricultural commodities and trade patterns. Overall, the biggest agricultural producers (China and the United States) could experience the greatest absolute cost from further species invasions. However, developing countries, in particular, Sub-Saharan African countries, appear most vulnerable in relative terms. Furthermore, China and the United States represent the greatest potential sources of invasive species for the rest of the world. The analysis reveals considerable scope for ongoing redistribution of known invasive pests and highlights the need for international cooperation to slow their spread.

  2. Chilli anthracnose disease caused by Colletotrichum species

    Institute of Scientific and Technical Information of China (English)

    Po Po THAN; Haryudian PRIHASTUTI; Sitthisack PHOULIVONG; Paul W.J. TAYLOR; Kevin D. HYDE

    2008-01-01

    Anthracnose disease is one of the major economic constraints to chilli production worldwide, especially in tropical and subtropical regions. Accurate taxonomic information is necessary for effective disease control management. In the Colletotrichum patho-system, different Colletotrichum species can be associated with anthracnose of the same host. Little information is known concerning the interactions of the species associated with the chilli anthracnose although several Colletotrichum species have been reported as causal agents of chilli anthracnose disease worldwide. The ambiguous taxonomic status of Colletotrichum species has resulted in inaccurate identification which may cause practical problems in plant breeding and disease management. Although the management and control of anthracnose disease are still being extensively researched, commercial eultivars of Capsicum annuum that are resistant to the pathogens that cause chilli anthracnose have not yet been developed. This paper reviews the causal agents of chilli anthracnose, the disease cycle, conventional methods in identification of the pathogen and molecular approaches that have been used for the identification of Colletotrichum species. Pathogenetic variation and population structure of the causal agents of chilli anthracnose along with the current taxonomic status of Colletotrichum species are discussed. Future developments leading to the disease management strategies are suggested.

  3. Chilli anthracnose disease caused by Colletotrichum species.

    Science.gov (United States)

    Than, Po Po; Prihastuti, Haryudian; Phoulivong, Sitthisack; Taylor, Paul W J; Hyde, Kevin D

    2008-10-01

    Anthracnose disease is one of the major economic constraints to chilli production worldwide, especially in tropical and subtropical regions. Accurate taxonomic information is necessary for effective disease control management. In the Colletotrichum patho-system, different Colletotrichum species can be associated with anthracnose of the same host. Little information is known concerning the interactions of the species associated with the chilli anthracnose although several Colletotrichum species have been reported as causal agents of chilli anthracnose disease worldwide. The ambiguous taxonomic status of Colletotrichum species has resulted in inaccurate identification which may cause practical problems in plant breeding and disease management. Although the management and control of anthracnose disease are still being extensively researched, commercial cultivars of Capsicum annuum that are resistant to the pathogens that cause chilli anthracnose have not yet been developed. This paper reviews the causal agents of chilli anthracnose, the disease cycle, conventional methods in identification of the pathogen and molecular approaches that have been used for the identification of Colletotrichum species. Pathogenetic variation and population structure of the causal agents of chilli anthracnose along with the current taxonomic status of Colletotrichum species are discussed. Future developments leading to the disease management strategies are suggested.

  4. Impacts of Species Misidentification on Species Distribution Modeling with Presence-Only Data

    Directory of Open Access Journals (Sweden)

    Hugo Costa

    2015-11-01

    Full Text Available Spatial records of species are commonly misidentified, which can change the predicted distribution of a species obtained from a species distribution model (SDM. Experiments were undertaken to predict the distribution of real and simulated species using MaxEnt and presence-only data “contaminated” with varying rates of misidentification error. Additionally, the difference between the niche of the target and contaminating species was varied. The results show that species misidentification errors may act to contract or expand the predicted distribution of a species while shifting the predicted distribution towards that of the contaminating species. Furthermore the magnitude of the effects was positively related to the ecological distance between the species’ niches and the size of the error rates. Critically, the magnitude of the effects was substantial even when using small error rates, smaller than common average rates reported in the literature, which may go unnoticed while using a standard evaluation method, such as the area under the receiver operating characteristic curve. Finally, the effects outlined were shown to impact negatively on practical applications that use SDMs to identify priority areas, commonly selected for various purposes such as management. The results highlight that species misidentification should not be neglected in species distribution modeling.

  5. Species Tree Inference Using a Mixture Model.

    Science.gov (United States)

    Ullah, Ikram; Parviainen, Pekka; Lagergren, Jens

    2015-09-01

    Species tree reconstruction has been a subject of substantial research due to its central role across biology and medicine. A species tree is often reconstructed using a set of gene trees or by directly using sequence data. In either of these cases, one of the main confounding phenomena is the discordance between a species tree and a gene tree due to evolutionary events such as duplications and losses. Probabilistic methods can resolve the discordance by coestimating gene trees and the species tree but this approach poses a scalability problem for larger data sets. We present MixTreEM-DLRS: A two-phase approach for reconstructing a species tree in the presence of gene duplications and losses. In the first phase, MixTreEM, a novel structural expectation maximization algorithm based on a mixture model is used to reconstruct a set of candidate species trees, given sequence data for monocopy gene families from the genomes under study. In the second phase, PrIME-DLRS, a method based on the DLRS model (Åkerborg O, Sennblad B, Arvestad L, Lagergren J. 2009. Simultaneous Bayesian gene tree reconstruction and reconciliation analysis. Proc Natl Acad Sci U S A. 106(14):5714-5719), is used for selecting the best species tree. PrIME-DLRS can handle multicopy gene families since DLRS, apart from modeling sequence evolution, models gene duplication and loss using a gene evolution model (Arvestad L, Lagergren J, Sennblad B. 2009. The gene evolution model and computing its associated probabilities. J ACM. 56(2):1-44). We evaluate MixTreEM-DLRS using synthetic and biological data, and compare its performance with a recent genome-scale species tree reconstruction method PHYLDOG (Boussau B, Szöllősi GJ, Duret L, Gouy M, Tannier E, Daubin V. 2013. Genome-scale coestimation of species and gene trees. Genome Res. 23(2):323-330) as well as with a fast parsimony-based algorithm Duptree (Wehe A, Bansal MS, Burleigh JG, Eulenstein O. 2008. Duptree: a program for large-scale phylogenetic

  6. SPECIES IDENTIFICATION OF MEAT BY ELECTROPHORETIC METHODS

    Directory of Open Access Journals (Sweden)

    Edward Pospiech

    2007-03-01

    Full Text Available Electrophoretic methods can be used to identify meat of various animal species. The protein electrophoresis, especially the IEF of the sarcoplasmic proteins, is a well-established technique for species identification of raw fish and is used in the control of seafood authenticity. However, in the case of the analysis of heat-processed fish, the method is applicable only to those species which possess characteristic patterns of the heat-stable parvalbumins. Heat-denatured fish muscle proteins may be solubilised by urea or sodium dodecylsulfate (SDS and separated by urea-IEF or SDS-PAGE, respectively. The comparison of these two methods allowed to conclude that, basically, each of them can be used for species identification of heated fishery products. However, extensively washed products may be preferentially analysed by the SDS-PAGE, because most of the parvalbumins are washed out leaving mainly myosins. On the other hand, the IEF method may be preferred for the differentiation of closely related species rich in parvalbumins isoforms. It is evident from the literature data that species-specific protein separations yield proteins of low molecular weight made up of three light chains of myosin (14-23 kDa, troponin (19-30 kDa and parvalbumin (about 12 kDa. Investigations showed that the SDS-PAGE method can be used to identify meats of: cattle, sheep, lambs, goats, red deer and rabbits. The technique allowed researchers to identify the following myofibrillar and sarcoplasmic muscle proteins: myosin and actin, α-actinin, tropomyosin, troponin. SDS-PAGE allowed the identification of myofibrillar proteins taking into account their molecular weights which was not possible with the assistance of the PAGIF because too many protein bands were obtained. It was possible to obtain differences in the separation of proteins characteristic for certain species, e.g. beef, resulting from the presence of sin-gle myofibrillar proteins.

  7. Reconciliation with non-binary species trees.

    Science.gov (United States)

    Vernot, Benjamin; Stolzer, Maureen; Goldman, Aiton; Durand, Dannie

    2008-10-01

    Reconciliation extracts information from the topological incongruence between gene and species trees to infer duplications and losses in the history of a gene family. The inferred duplication-loss histories provide valuable information for a broad range of biological applications, including ortholog identification, estimating gene duplication times, and rooting and correcting gene trees. While reconciliation for binary trees is a tractable and well studied problem, there are no algorithms for reconciliation with non-binary species trees. Yet a striking proportion of species trees are non-binary. For example, 64% of branch points in the NCBI taxonomy have three or more children. When applied to non-binary species trees, current algorithms overestimate the number of duplications because they cannot distinguish between duplication and incomplete lineage sorting. We present the first algorithms for reconciling binary gene trees with non-binary species trees under a duplication-loss parsimony model. Our algorithms utilize an efficient mapping from gene to species trees to infer the minimum number of duplications in O(|V(G) | x (k(S) + h(S))) time, where |V(G)| is the number of nodes in the gene tree, h(S) is the height of the species tree and k(S) is the size of its largest polytomy. We present a dynamic programming algorithm which also minimizes the total number of losses. Although this algorithm is exponential in the size of the largest polytomy, it performs well in practice for polytomies with outdegree of 12 or less. We also present a heuristic which estimates the minimal number of losses in polynomial time. In empirical tests, this algorithm finds an optimal loss history 99% of the time. Our algorithms have been implemented in NOTUNG, a robust, production quality, tree-fitting program, which provides a graphical user interface for exploratory analysis and also supports automated, high-throughput analysis of large data sets.

  8. Biological review of 82 species of coral petitioned to be included in the Endangered Species Act

    Science.gov (United States)

    Brainard, Russell E.; Birkeland, Charles; Eakin, C. Mark; McElhany, Paul; Miller, Margaret W.; Patterson, Matt; Piniak, G.A.

    2011-01-01

    list 83 coral species as threatened or endangered under the U.S. Endangered Species Act. The petition was based on a predicted decline in available habitat for the species, citing anthropogenic climate change and ocean acidification as the lead factors among the various stressors responsible for the potential decline. The NMFS identified 82 of the corals as candidate species, finding that the petition provided substantive information for a potential listing of these species. The NMFS established a Biological Review Team (BRT) to prepare this Status Review Report that examines the status of these 82 candidate coral species and evaluates extinction risk for each of them. This document makes no recommendations for listing, as that is a separate evaluation to be conducted by the NMFS.

  9. Data on the fungal species consumed by mammal species in Australia.

    Science.gov (United States)

    Nuske, S J; Vernes, K; May, T W; Claridge, A W; Congdon, B C; Krockenberger, A; Abell, S E

    2017-06-01

    The data reported here support the manuscript Nuske et al. (2017) [1]. Searches were made for quantitative data on the occurrence of fungi within dietary studies of Australian mammal species. The original location reported in each study was used as the lowest grouping variable within the dataset. To standardise the data and compare dispersal events from populations of different mammal species that might overlap, data from locations were further pooled and averaged across sites if they occurred within 100 km of a random central point. Three locations in Australia contained data on several (>7) mycophagous mammals, all other locations had data on 1-3 mammal species. Within these three locations, the identity of the fungi species was compared between mammal species' diets. A list of all fungi species found in Australian mammalian diets is also provide along with the original reference and fungal synonym names.

  10. Molecular approaches to identify cryptic species and polymorphic species within a complex community of fig wasps.

    Directory of Open Access Journals (Sweden)

    Jin-Hua Xiao

    Full Text Available Cryptic and polymorphic species can complicate traditional taxonomic research and both of these concerns are common in fig wasp communities. Species identification is very difficult, despite great effort and the ecological importance of fig wasps. Herein, we try to identify all chalcidoid wasp species hosted by one species of fig, using both morphological and molecular methods. We compare the efficiency of four different DNA regions and find that ITS2 is highly effective for species identification, while mitochondrial COI and Cytb regions appear less reliable, possibly due to the interference signals from either nuclear copies of mtDNA, i.e. NUMTs, or the effects of Wolbachia infections. The analyses suggest that combining multiple markers is the best choice for inferring species identifications as any one marker may be unsuitable in a given case.

  11. Seasonal species interactions minimize the impact of species turnover on the likelihood of community persistence

    OpenAIRE

    Saavedra, Serguei; Rudolf P. Rohr; Fortuna, Miguel A.; Selva, Nuria; Bascompte, Jordi

    2015-01-01

    Many of the observed species interactions embedded in ecological communities are not permanent, but are characterized by temporal changes that are observed along with abiotic and biotic variations. While work has been done describing and quantifying these changes, little is known about their consequences for species coexistence. Here, we investigate the extent to which changes of species composition impact the likelihood of persistence of the predator–prey community in the highly seasonal Bia...

  12. The 'taygetis Ypthima Species Group' (lepidoptera, Nymphalidae, Satyrinae): Taxonomy, Variation And Description Of A New Species.

    OpenAIRE

    Ricardo Siewert; Thamara Zacca; Fernando Dias; André Freitas; Olaf Mielke; Mirna Casagrande

    2013-01-01

    A new species of Taygetis Hübner, [1819] (Lepidoptera, Nymphalidae, Satyrinae) from southeastern Brazil is described: Taygetis drogoni sp. n. In addition, T. servius Weymer, 1910 and T. fulginia d’Almeida, 1922 are resurrected from synonymy and a taxonomic discussion on the species T. ypthima Hübner, [1821] and T. rectifascia Weymer, 1907 is provided. A dichotomous key for the species is also provided.

  13. Evaluating Hypotheses of Plant Species Invasions on Mediterranean Islands: Inverse Patterns between Alien and Endemic Species

    Directory of Open Access Journals (Sweden)

    Alexander Bjarnason

    2017-08-01

    Full Text Available Invasive alien species cause major changes to ecosystem functioning and patterns of biodiversity, and the main factors involved in invasion success remain contested. Using the Mediterranean island of Crete, Greece as a case study, we suggest a framework for analyzing spatial data of alien species distributions, based on environmental predictors, aiming to gain an understanding of their spatial patterns and spread. Mediterranean islands are under strong ecological pressure from invading species due to their restricted size and increased human impact. Four hypotheses of invasibility, the “propagule pressure hypothesis” (H1, “biotic resistance hypothesis vs. acceptance hypothesis” (H2, “disturbance-mediated hypothesis” (H3, and “environmental heterogeneity hypothesis” (H4 were tested. Using data from alien, native, and endemic vascular plant species, the propagule pressure, biotic resistance vs. acceptance, disturbance-mediated, and environmental heterogeneity hypotheses were tested with Generalized Additive Modeling (GAM of 39 models. Based on model selection, the optimal model includes the positive covariates of native species richness, the negative covariates of endemic species richness, and land area. Variance partitioning between the four hypotheses indicated that the biotic resistance vs. acceptance hypothesis explained the vast majority of the total variance. These results show that areas of high species richness have greater invasibility and support the acceptance hypothesis and “rich-get-richer” distribution of alien species. The negative correlation between alien and endemic species appears to be predominantly driven by altitude, with fewer alien and more endemic species at greater altitudes, and habitat richness. The negative relationship between alien and endemic species richness provides potential for understanding patterns of endemic and alien species on islands, contributing to more effective conservation

  14. New species of Graphocaecilius Enderlein (Psocodea: 'Psocoptera': Lachesillidae) from Colombia.

    Science.gov (United States)

    Arango, Stephania Sandoval; Obando, Ranulfo González; Aldrete, Alfonso Neri García

    2016-08-05

    Three new species of Graphocaecilius Enderlein are here described and illustrated; the species were found in the Colombian departments of Valle del Cauca and Risaralda, raising to five the number of species of this genus in Colombia, making it the most species rich country for Graphocaecilius in South America. A key to the species in the genus is included.

  15. Two new species of Gyrocotyle (Monogenea from Chimaerids (Holocephali))

    NARCIS (Netherlands)

    Land, van der J.; Dienske, H.

    1968-01-01

    INTRODUCTION Species of the genus Gyrocotyle are quite common intestinal parasites of chimaerids. As far as we now know, each parasite species is restricted to one host species. In each host species, however, a second and much rarer species of Gyrocotyle may occur besides the common one. The common

  16. Diffuse coevolution between two Epicephala species (Gracillariidae and two Breynia species (Phyllanthaceae.

    Directory of Open Access Journals (Sweden)

    Jing Zhang

    Full Text Available The diffuse coevolution between two moth species (Epicephala lativalvaris and E. mirivalvata and two plant species (Breynia fruticosa and B. rostrata is reported based on field observations and indoor experiments conducted in Hainan and Fujian, China. Study results showed that the two Epicephala species jointly pollinated the two Breynia species, which led to a unique obligate pollination mutualism of two-to-two species specificity. A single Epicephala larva exclusively fed on seeds of host plants and developed to maturity by consuming all six seeds of each fruit, whereas a fraction of intact fruits were left to ensure the reproduction of plants within the whole population. Larvae of the two Epicephala species are competitive for resources; the population of E. mirivalvata is much smaller than that of E. lativalvaris, which has resulted from the differences in the female ovipositor structures and oviposition mode. The life history of Epicephala species highly coincides with the phenology of Breynia plants, and different phenology of B. fruticosa resulted in the different life history of the two Epicephala species in Hainan and Fujian. The natural hybridization of two host plants, possibly induced by the alternate pollination of two Epicephala species, is briefly discussed.

  17. Species status and conservation issues of New Zealand's endemic Latrodectus spider species (Araneae: Theridiidae)

    DEFF Research Database (Denmark)

    Vink, Cor J; Sirvid, Phillip J; Malumbres-Olarte, Jagoba;

    2008-01-01

    New Zealand has two endemic widow spiders, Latrodectus katipo Powell, 1871 and L. atritus Urquhart, 1890. Both species face many conservation threats and are actively managed. The species status of the Latrodectus spiders of New Zealand was assessed using molecular (COI, ITS1, ITS2) and morpholog......New Zealand has two endemic widow spiders, Latrodectus katipo Powell, 1871 and L. atritus Urquhart, 1890. Both species face many conservation threats and are actively managed. The species status of the Latrodectus spiders of New Zealand was assessed using molecular (COI, ITS1, ITS2...... was also detected and its conservation implications are discussed....

  18. Seasonal species interactions minimize the impact of species turnover on the likelihood of community persistence.

    Science.gov (United States)

    Saavedra, Serguei; Rohr, Rudolf P; Fortuna, Miguel A; Selva, Nuria; Bascompte, Jordi

    2016-04-01

    Many of the observed species interactions embedded in ecological communities are not permanent, but are characterized by temporal changes that are observed along with abiotic and biotic variations. While work has been done describing and quantifying these changes, little is known about their consequences for species coexistence. Here, we investigate the extent to which changes of species composition impact the likelihood of persistence of the predator-prey community in the highly seasonal Białowieza Primeval Forest (northeast Poland), and the extent to which seasonal changes of species interactions (predator diet) modulate the expected impact. This likelihood is estimated extending recent developments on the study of structural stability in ecological communities. We find that the observed species turnover strongly varies the likelihood of community persistence between summer and winter. Importantly, we demonstrate that the observed seasonal interaction changes minimize the variation in the likelihood of persistence associated with species turnover across the year. We find that these community dynamics can be explained as the coupling of individual species to their environment by minimizing both the variation in persistence conditions and the interaction changes between seasons. Our results provide a homeostatic explanation for seasonal species interactions and suggest that monitoring the association of interactions changes with the level of variation in community dynamics can provide a good indicator of the response of species to environmental pressures.

  19. Are introduced species better dispersers than native species? A global comparative study of seed dispersal distance.

    Science.gov (United States)

    Flores-Moreno, Habacuc; Thomson, Fiona J; Warton, David I; Moles, Angela T

    2013-01-01

    We provide the first global test of the idea that introduced species have greater seed dispersal distances than do native species, using data for 51 introduced and 360 native species from the global literature. Counter to our expectations, there was no significant difference in mean or maximum dispersal distance between introduced and native species. Next, we asked whether differences in dispersal distance might have been obscured by differences in seed mass, plant height and dispersal syndrome, all traits that affect dispersal distance and which can differ between native and introduced species. When we included all three variables in the model, there was no clear difference in dispersal distance between introduced and native species. These results remained consistent when we performed analyses including a random effect for site. Analyses also showed that the lack of a significant difference in dispersal distance was not due to differences in biome, taxonomic composition, growth form, nitrogen fixation, our inclusion of non-invasive introduced species, or our exclusion of species with human-assisted dispersal. Thus, if introduced species do have higher spread rates, it seems likely that these are driven by differences in post-dispersal processes such as germination, seedling survival, and survival to reproduction.

  20. Species of the Poaceae-associated genus Bamboosiella (Thysanoptera, Phlaeothripidae) from China, with three new species.

    Science.gov (United States)

    Dang, Li-Hong; Qiao, Ge-Xia

    2016-11-07

    In the Poaceae-associated genus Bamboosiella Ananthakrishnan, eleven species are here recognized from China, including antennatus sp.n. and longisetis sp.n. from Yunnan, and magnus sp.n. from Hainan. Four species are newly recorded from China, bicoloripes Ananthakrishnan, fasciata Okajima, flavescens Okajima and semiflava Okajima. One species from Zhejiang, Bamboosiella brevibristla Sha, Guo, Feng & Duan is placed as a new synonym of B. exastis (Ananthakrishnan & Kudo). An illustrated identification key is provided to the eleven Bamboosiella species now recognised from China.

  1. Spatial factor analysis: a new tool for estimating joint species distributions and correlations in species range

    DEFF Research Database (Denmark)

    Thorson, James T.; Scheuerell, Mark D.; Shelton, Andrew O.;

    2015-01-01

    1. Predicting and explaining the distribution and density of species is one of the oldest concerns in ecology. Species distributions can be estimated using geostatistical methods, which estimate a latent spatial variable explaining observed variation in densities, but geostatistical methods may...... be imprecise for species with low densities or few observations. Additionally, simple geostatistical methods fail to account for correlations in distribution among species and generally estimate such cross-correlations as a post hoc exercise. 2. We therefore present spatial factor analysis (SFA), a spatial...

  2. Missing in action: Species competition is a neglected predictor variable in species distribution modelling.

    Science.gov (United States)

    Mpakairi, Kudzai Shaun; Ndaimani, Henry; Tagwireyi, Paradzayi; Gara, Tawanda Winmore; Zvidzai, Mark; Madhlamoto, Daphine

    2017-01-01

    The central role of species competition in shaping community structure in ecosystems is well appreciated amongst ecologists. However species competition is a consistently missing variable in Species Distribution Modelling (SDM). This study presents results of our attempt to incorporate species competition in SDMs. We used a suit of predictor variables including Soil Adjusted Vegetation Index (SAVI), as well as distance from roads, settlements and water, fire frequency and distance from the nearest herbivore sighting (of selected herbivores) to model individual habitat preferences of five grazer species (buffalo, warthog, waterbuck, wildebeest and zebra) with the Ensemble SDM algorithm for Gonarezhou National Park, Zimbabwe. Our results showed that distance from the nearest animal sighting (a proxy for competition among grazers) was the best predictor of the potential distribution of buffalo, wildebeest and zebra but the second best predictor for warthog and waterbuck. Our findings provide evidence to that competition is an important predictor of grazer species' potential distribution. These findings suggest that species distribution modelling that neglects species competition may be inadequate in explaining the potential distribution of species. Therefore our findings encourage the inclusion of competition in SDM as well as potentially igniting discussions that may lead to improving the predictive power of future SDM efforts.

  3. Historical Species Distribution Models Predict Species Limits in Western Plethodon Salamanders.

    Science.gov (United States)

    Pelletier, Tara A; Crisafulli, Charlie; Wagner, Steve; Zellmer, Amanda J; Carstens, Bryan C

    2015-11-01

    Allopatry is commonly used to predict boundaries in species delimitation investigations under the assumption that currently allopatric distributions are indicative of reproductive isolation; however, species ranges are known to change over time. Incorporating a temporal perspective of geographic distributions should improve species delimitation; to explore this, we investigate three species of western Plethodon salamanders that have shifted their ranges since the end of the Pleistocene. We generate species distribution models (SDM) of the current range, hindcast these models onto a climatic model 21 Ka, and use three molecular approaches to delimit species in an integrated fashion. In contrast to expectations based on the current distribution, we detect no independent lineages in species with allopatric and patchy distributions (Plethodon vandykei and Plethodon larselli). The SDMs indicate that probable habitat is more expansive than their current range, especially during the last glacial maximum (LGM) (21 Ka). However, with a contiguous distribution, two independent lineages were detected in Plethodon idahoensis, possibly due to isolation in multiple glacial refugia. Results indicate that historical SDMs are a better predictor of species boundaries than current distributions, and strongly imply that researchers should incorporate SDM and hindcasting into their investigations and the development of species hypotheses. © The Author(s) 2014. Published by Oxford University Press, on behalf of the Society of Systematic Biologists. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  4. Species richness, area and climate correlates

    DEFF Research Database (Denmark)

    Nogues, David Bravo; Bastos Araujo, Miguel

    2006-01-01

    affects: (1) the selection of climate variables entering a species richness model; and (2) the accuracy of models in predicting species richness in unsampled grid cells. Location Western Europe. Methods Models are developed for European plant, breeding bird, mammal and herptile species richness using...... seven climate variables. Generalized additive models are used to relate species richness, climate and area. Results We found that variation in the grid cell area was large (50 × 50 km: 8-3311 km2; 220 × 220: 193-55,100 km2), but this did not affect the selection of variables in the models. Similarly...... support the assumption that variation in near-equal area cells may be of second-order importance for models explaining or predicting species richness in relation to climate, although there is a possibility that drops in accuracy might increase with grid cell size. The results are, however, contingent...

  5. New Potential Pharmaceutical Applications of Hypericum Species.

    Science.gov (United States)

    Marrelli, Mariangela; Statti, Giancarlo; Conforti, Filomena; Menichini, Francesco

    2016-01-01

    The genus Hypericum includes more than 450 species distributed in Europe, North America, North Africa and West Asia. These plants are widely used in folk medicine for the treatment of inflammation, bacterial and viral infections, burns and gastric disorders. The use for alleviating inflammation and promoting wound healing is well known for H. Perforatum L. (St. John's wort) and other species. Because of its pharmacological activity, H. perforatum L. is one of the most important species of this genus. This plant has been largely utilized for its efficacy in the treatment of mild to moderate depression. However, some other species have been utilized in traditional medicine and have been studied for their phytochemical composition and for their biological activities to date. Hypericum species contain biologically active secondary metabolites belonging to at least ten different classes, with prevalence of naphthodianthrones (hypericin and pseudohypericin), phloroglucinols (hyperforin), flavonoids (rutin, hyperoside, isoquercitrin, quercitrin, quercetin, amentoflavone) and phenylpropanoids (chlorogenic acid). However, great variations in contents have been reported for wild populations worldwide. The purpose of this review is to provide an overview of most recent studies about potential pharmaceutical applications of plants belonging to Hypericum genus. The most interesting isolated active principles and both in vitro and in vivo effects of Hypericum extracts are presented and discussed.

  6. Single-species microarrays and comparative transcriptomics.

    Directory of Open Access Journals (Sweden)

    Frédéric J J Chain

    Full Text Available BACKGROUND: Prefabricated expression microarrays are currently available for only a few species but methods have been proposed to extend their application to comparisons between divergent genomes. METHODOLOGY/PRINCIPAL FINDINGS: Here we demonstrate that the hybridization intensity of genomic DNA is a poor basis on which to select unbiased probes on Affymetrix expression arrays for studies of comparative transcriptomics, and that doing so produces spurious results. We used the Affymetrix Xenopus laevis microarray to evaluate expression divergence between X. laevis, X. borealis, and their F1 hybrids. When data are analyzed with probes that interrogate only sequences with confirmed identity in both species, we recover results that differ substantially analyses that use genomic DNA hybridizations to select probes. CONCLUSIONS/SIGNIFICANCE: Our findings have implications for the experimental design of comparative expression studies that use single-species microarrays, and for our understanding of divergent expression in hybrid clawed frogs. These findings also highlight important limitations of single-species microarrays for studies of comparative transcriptomics of polyploid species.

  7. Egyptian plant species as new ozone indicators.

    Science.gov (United States)

    Madkour, Samia A; Laurence, J A

    2002-01-01

    The aim of this study was to test and select one or more highly sensitive, specific and environmentally successful Egyptian bioindicator plants for ozone (O3). For that purpose more than 30 Egyptian species and cultivars were subjected to extensive screening studies under controlled environmental and pollutant exposure conditions to mimic the Egyptian environmental conditions and O3 levels in urban and rural sites. Four plant species were found to be more sensitive to O3 than the universally used O3-bioindicator, tobacco Bel W3, under the Egyptian environmental conditions used. These plant species, jute (Corchorus olitorius c.v. local), clover (Trifolium alexandrinum L. c.v. Masry), garden rocket (Eruca sativa c.v. local) and alfalfa (Medicago sativa L. c.v. local), ranked in order of decreasing sensitivity, exhibited typical O3 injury symptoms faster and at lower 03 concentrations than Bel W3. Three variables were tested in search of a reliable tool for the diagnosis and prediction of O3 response prior to the appearance of visible foliar symptoms: pigment degradation, stomatal conductance (g(s)) and net photosynthetic CO2 assimilation (Pnet). Pigment degradation was found to be unreliable in predicting species sensitivity to O3. Evidence supporting stomatal conductance involvement in 03 tolerance was found only in tolerant species. A good correlation was found between g(s), restriction of O3 and CO2 influx into the mesophyll tissues, and Pnet. Changes in Pnet seemed to depend largely on fluctuations in g(s).

  8. Stabilization of reactive species by supramolecular encapsulation.

    Science.gov (United States)

    Galan, Albano; Ballester, Pablo

    2016-03-21

    Molecular containers have attracted the interest of supramolecular chemists since the early beginnings of the field. Cavitands' inner cavities were quickly exploited by Cram and Warmuth to construct covalent containers able to stabilize and assist the characterization of short-lived reactive species such as cyclobutadiene or o-benzyne. Since then, more complex molecular architectures have been prepared able to store and isolate a myriad of fleeting species (i.e. organometallic compounds, cationic species, radical initiators…). In this review we cover selected examples of the stabilization of reactive species by encapsulation in molecular containers from the first reports of covalent containers described by Cram et al. to the most recent examples of containers with self-assembled structure (metal coordination cages and hydrogen bonded capsules). Finally, we briefly review examples reported by Rebek et al. in which elusive reaction intermediates could be detected in the inner cavities of self-folding resorcin[4]arene cavitands by the formation of covalent host-guest complexes. The utilization of encapsulated reactive species in catalysis or synthesis is not covered.

  9. Diversity in protein glycosylation among insect species.

    Directory of Open Access Journals (Sweden)

    Gianni Vandenborre

    Full Text Available BACKGROUND: A very common protein modification in multicellular organisms is protein glycosylation or the addition of carbohydrate structures to the peptide backbone. Although the Class of the Insecta is the largest animal taxon on Earth, almost all information concerning glycosylation in insects is derived from studies with only one species, namely the fruit fly Drosophila melanogaster. METHODOLOGY/PRINCIPAL FINDINGS: In this report, the differences in glycoproteomes between insects belonging to several economically important insect orders were studied. Using GNA (Galanthus nivalis agglutinin affinity chromatography, different sets of glycoproteins with mannosyl-containing glycan structures were purified from the flour beetle (Tribolium castaneum, the silkworm (Bombyx mori, the honeybee (Apis mellifera, the fruit fly (D. melanogaster and the pea aphid (Acyrthosiphon pisum. To identify and characterize the purified glycoproteins, LC-MS/MS analysis was performed. For all insect species, it was demonstrated that glycoproteins were related to a broad range of biological processes and molecular functions. Moreover, the majority of glycoproteins retained on the GNA column were unique to one particular insect species and only a few glycoproteins were present in the five different glycoprotein sets. Furthermore, these data support the hypothesis that insect glycoproteins can be decorated with mannosylated O-glycans. CONCLUSIONS/SIGNIFICANCE: The results presented here demonstrate that oligomannose N-glycosylation events are highly specific depending on the insect species. In addition, we also demonstrated that protein O-mannosylation in insect species may occur more frequently than currently believed.

  10. Independently evolving species in asexual bdelloid rotifers.

    Directory of Open Access Journals (Sweden)

    Diego Fontaneto

    2007-04-01

    Full Text Available Asexuals are an important test case for theories of why species exist. If asexual clades displayed the same pattern of discrete variation as sexual clades, this would challenge the traditional view that sex is necessary for diversification into species. However, critical evidence has been lacking: all putative examples have involved organisms with recent or ongoing histories of recombination and have relied on visual interpretation of patterns of genetic and phenotypic variation rather than on formal tests of alternative evolutionary scenarios. Here we show that a classic asexual clade, the bdelloid rotifers, has diversified into distinct evolutionary species. Intensive sampling of the genus Rotaria reveals the presence of well-separated genetic clusters indicative of independent evolution. Moreover, combined genetic and morphological analyses reveal divergent selection in feeding morphology, indicative of niche divergence. Some of the morphologically coherent groups experiencing divergent selection contain several genetic clusters, in common with findings of cryptic species in sexual organisms. Our results show that the main causes of speciation in sexual organisms, population isolation and divergent selection, have the same qualitative effects in an asexual clade. The study also demonstrates how combined molecular and morphological analyses can shed new light on the evolutionary nature of species.

  11. Summary statistics for fossil spider species taxonomy

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    David Penney

    2012-05-01

    Full Text Available Spiders (Araneae are one of the most species-rich orders on Earth today, and also have one of the longest geological records of any terrestrial animal groups, as demonstrated by their extensive fossil record. There are currently around 1150 described fossil spider species, representing 2.6% of all described spiders (i.e. extinct and extant. Data for numbers of fossil and living spider taxa described annually (and various other metrics for the fossil taxa were compiled from current taxonomic catalogues. Data for extant taxa showed a steady linear increase of approximately 500 new species per year over the last decade, reflecting a rather constant research activity in this area by a large number of scientists, which can be expected to continue. The results for fossil species were very different, with peaks of new species descriptions followed by long troughs, indicating minimal new published research activity for most years. This pattern is indicative of short bursts of research by a limited number of authors. Given the frequent discovery of new fossil deposits containing spiders, a wealth of new material coming to light from previously worked deposits, and the application of new imaging techniques in palaeoarachnology that allow us to extract additional data from historical specimens, e.g. X-ray computed tomography, it is important not only to ensure a sustained research activity on fossil spiders (and other arachnids through training and enthusing the next generation of palaeoarachnologists, but preferably to promote increased research and expertise in this field.

  12. Reconciliation of Gene and Species Trees

    Directory of Open Access Journals (Sweden)

    L. Y. Rusin

    2014-01-01

    Full Text Available The first part of the paper briefly overviews the problem of gene and species trees reconciliation with the focus on defining and algorithmic construction of the evolutionary scenario. Basic ideas are discussed for the aspects of mapping definitions, costs of the mapping and evolutionary scenario, imposing time scales on a scenario, incorporating horizontal gene transfers, binarization and reconciliation of polytomous trees, and construction of species trees and scenarios. The review does not intend to cover the vast diversity of literature published on these subjects. Instead, the authors strived to overview the problem of the evolutionary scenario as a central concept in many areas of evolutionary research. The second part provides detailed mathematical proofs for the solutions of two problems: (i inferring a gene evolution along a species tree accounting for various types of evolutionary events and (ii trees reconciliation into a single species tree when only gene duplications and losses are allowed. All proposed algorithms have a cubic time complexity and are mathematically proved to find exact solutions. Solving algorithms for problem (ii can be naturally extended to incorporate horizontal transfers, other evolutionary events, and time scales on the species tree.

  13. SPECIES DIVERSITY AND STABILITY OF BIRD COMMUNITIES

    Directory of Open Access Journals (Sweden)

    Matsyura M.V.

    2011-12-01

    Full Text Available When comparing the suggested stability indicators, we obtained statistically significant correlations for indicators of annual stability of species and total number and standard deviation of the logarithm of the number. Annual Stability Index can be applied with a high degree of reliability as a characteristic of the averaged structure of the community and its pyramid of abundances. The results of correlation analysis confirm our assumptions about the correlation between stability over the years and indices of species diversity and relative uniformity.The final task of the study was to create a mathematical model of stability, where the independent variables are the indices of species diversity. The calculation of these indices allows forecasting birds’ community stability. According to the result of multiple regression for the indicators of diversity and stability of the breeding birds’ community highest correlation coefficients were obtained fro Shannon index and Simpson's dominance Index.Community stability could be determined by its overall species diversity. When considering the stability of community its diversity should be considered as a combination of uniformity of their total number and number of species. The most suitable predictors for the community stability were the nonparametric index of dominance and information-statistical indices, since they considered simultaneously evenness and richness. The community stability is subject of the complexity of its internal communications pattern.

  14. Dynamics of genome change among Legionella species

    Science.gov (United States)

    Joseph, Sandeep J.; Cox, Daniel; Wolff, Bernard; Morrison, Shatavia S.; Kozak-Muiznieks, Natalia A.; Frace, Michael; Didelot, Xavier; Castillo-Ramirez, Santiago; Winchell, Jonas; Read, Timothy D.; Dean, Deborah

    2016-01-01

    Legionella species inhabit freshwater and soil ecosystems where they parasitize protozoa. L. pneumonphila (LP) serogroup-1 (Lp1) is the major cause of Legionnaires’ Disease (LD), a life-threatening pulmonary infection that can spread systemically. The increased global frequency of LD caused by Lp and non-Lp species underscores the need to expand our knowledge of evolutionary forces underlying disease pathogenesis. Whole genome analyses of 43 strains, including all known Lp serogroups 1–17 and 17 emergent LD-causing Legionella species (of which 33 were sequenced in this study) in addition to 10 publicly available genomes, resolved the strains into four phylogenetic clades along host virulence demarcations. Clade-specific genes were distinct for genetic exchange and signal-transduction, indicating adaptation to specific cellular and/or environmental niches. CRISPR spacer comparisons hinted at larger pools of accessory DNA sequences in Lp than predicted by the pan-genome analyses. While recombination within Lp was frequent and has been reported previously, population structure analysis identified surprisingly few DNA admixture events between species. In summary, diverse Legionella LD–causing species share a conserved core-genome, are genetically isolated from each other, and selectively acquire genes with potential for enhanced virulence. PMID:27633769

  15. Patterns of species ranges, speciation, and extinction.

    Science.gov (United States)

    Birand, Aysegul; Vose, Aaron; Gavrilets, Sergey

    2012-01-01

    The exact nature of the relationship among species range sizes, speciation, and extinction events is not well understood. The factors that promote larger ranges, such as broad niche widths and high dispersal abilities, could increase the likelihood of encountering new habitats but also prevent local adaptation due to high gene flow. Similarly, low dispersal abilities or narrower niche widths could cause populations to be isolated, but such populations may lack advantageous mutations due to low population sizes. Here we present a large-scale, spatially explicit, individual-based model addressing the relationships between species ranges, speciation, and extinction. We followed the evolutionary dynamics of hundreds of thousands of diploid individuals for 200,000 generations. Individuals adapted to multiple resources and formed ecological species in a multidimensional trait space. These species varied in niche widths, and we observed the coexistence of generalists and specialists on a few resources. Our model shows that species ranges correlate with dispersal abilities but do not change with the strength of fitness trade-offs; however, high dispersal abilities and low resource utilization costs, which favored broad niche widths, have a strong negative effect on speciation rates. An unexpected result of our model is the strong effect of underlying resource distributions on speciation: in highly fragmented landscapes, speciation rates are reduced.

  16. Pain, Cannabis Species, and Cannabis Use Disorders.

    Science.gov (United States)

    Cohen, Nicole L; Heinz, Adrienne J; Ilgen, Mark; Bonn-Miller, Marcel O

    2016-05-01

    The purpose of this study was to examine whether individuals who used medical cannabis for chronic pain were at increased risk for cannabis use problems compared with individuals who used medical cannabis for other reasons (e.g., anxiety, insomnia, and muscle spasms). An additional aim was to determine whether individuals who used cannabis for chronic pain, as well as those who reported greater within-group pain levels, demonstrated a species preference (i.e., sativa, indica, hybrids) and the extent to which species preference was associated with cannabis use problems. Participants were 163 medical cannabis users (77% male), recruited from a medical marijuana dispensary in California, who completed assessments of medical cannabis use motives, history, preferences (species type), and problems, as well as current pain level. Individuals who used cannabis to manage chronic pain experienced fewer cannabis use problems than those who did not use it for pain; among those who used it for pain, the average pain level in the past week was not associated with cannabis use problems. Furthermore, individuals who used cannabis for chronic pain were more likely to use indica over sativa. Preference for indica was associated with fewer cannabis use problems than preference for hybrid species. Individuals who use cannabis to manage chronic pain may be at a lower risk for cannabis use problems, relative to individuals who use it for other indications, potentially as a function of their species preference.

  17. Genetic homogeneity between two populations of the parthenogenetic lizard Aspidoscelis cozumela Homogeneidad genética entre dos poblaciones de la lagartija partenogenética Aspidoscelis cozumela

    Directory of Open Access Journals (Sweden)

    Norma L. Manríquez-Morán

    2008-12-01

    Full Text Available We used skin-grafting to assess the genetic variability between 2 populations of the parthenogenetic lizard Aspidoscelis cozumela. We transplanted 238 skin fragments among individuals of 2 coastal populations at Cozumel Island. Grafts belonging to individuals that survive more than 60 days suggested genetic homogeneity between both populations, consistent with the existence of only 1 clone within this unisexual species.Se utilizó el método de transplantes de piel para evaluar la variabilidad genética entre 2 poblaciones de la lagartija partenogenética Aspidoscelis cozumela. Se transplantaron 238 fragmentos de piel entre individuos de 2 poblaciones costeras de Isla Cozumel. Los transplantes pertenecientes a individuos que vivieron más de 60 días, mostraron homogeneidad genética entre ambas poblaciones, lo cual sugiere la existencia de 1 sólo clon dentro de esta especie unisexual.

  18. Biodiversity of wild fruit species of Serbia

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    Bošnjaković Dušica

    2012-01-01

    Full Text Available Several field collecting trips in the 2009-2011 period confirmed that forest fruit species are an inexhaustible genofond of extremely important varieties that yield fruit of excellent quality and high nutritive value, with wide range of applications, including nutritional, medicinal and food production. The aim of this work was to develop long term interactive and integrated strategy for selection of wild fruit species through different breeding methods, as well as popularization of selected products and their integration into intensive fruit growing. The most important morphological, ecological, and biological characteristics were studied and presented for Cornus mas, Sambucus nigra, Morus sp. and Rosa sp. For each studied fruit species, advanced selections for cultivar release has been reported.

  19. Capsular Polysaccharide Expression in Commensal Streptococcus Species

    DEFF Research Database (Denmark)

    Skov Sørensen, Uffe B; Yao, Kaihu; Yang, Yonghong

    2016-01-01

    Expression of a capsular polysaccharide is considered a hallmark of most invasive species of bacteria, including Streptococcus pneumoniae, in which the capsule is among the principal virulence factors and is the basis for successful vaccines. Consequently, it was previously assumed that capsule...... evolved by import of cps fragments from commensal Streptococcus species, resulting in a mosaic of genes of different origins. The demonstrated antigenic identity of at least eight of the numerous capsular polysaccharide structures expressed by commensal streptococci with recognized serotypes of S. pneumoniae...... of Streptococcus pneumoniae and is the basis for successful vaccines against infections caused by this important pathogen. Contrasting with previous assumptions, this study showed that expression of capsular polysaccharides by the same genetic mechanisms is a general property of closely related species...

  20. Androgen receptor gene polymorphism in zebra species

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    Hideyuki Ito

    2015-09-01

    Full Text Available Androgen receptor genes (AR have been found to have associations with reproductive development, behavioral traits, and disorders in humans. However, the influence of similar genetic effects on the behavior of other animals is scarce. We examined the loci AR glutamine repeat (ARQ in 44 Grevy's zebras, 23 plains zebras, and three mountain zebras, and compared them with those of domesticated horses. We observed polymorphism among zebra species and between zebra and horse. As androgens such as testosterone influence aggressiveness, AR polymorphism among equid species may be associated with differences in levels of aggression and tameness. Our findings indicate that it would be useful to conduct further studies focusing on the potential association between AR and personality traits, and to understand domestication of equid species.

  1. WHITE BLISTER SPECIES (Albuginaceae ON WEEDS

    Directory of Open Access Journals (Sweden)

    Karolina Vrandečić

    2011-06-01

    Full Text Available The obligate fungi inside the family Albuginaceae are widespread world wide and cause white rust or white blister disease. Mycopopulation of weeds has been researched within the project „The role of weeds in epidemiology of row-crop diseases“. The aim of this research was to identify white blister species occurring on weeds in Eastern Croatia. Weed plants with disease symptoms characteristic for white blister species have been collected since 2001 on location Slavonia and Baranja country. Determination of white blister species was based on morphological characters of pathogen and the host. Wilsoniana bliti was determined on Amaranthus retroflexus and Amaranthus hybridus leaves. Capsella bursa pastoris is a host for Albugo candida. Ambrosia artemisiifolia is a host for Pustula sp. and Cirsium arvense was found to be host for Pustula spinulosa. Wilsoniana portulaceae was determined on Portulaca oleracea.

  2. Computational botany methods for automated species identification

    CERN Document Server

    Remagnino, Paolo; Wilkin, Paul; Cope, James; Kirkup, Don

    2017-01-01

    This book discusses innovative methods for mining information from images of plants, especially leaves, and highlights the diagnostic features that can be implemented in fully automatic systems for identifying plant species. Adopting a multidisciplinary approach, it explores the problem of plant species identification, covering both the concepts of taxonomy and morphology. It then provides an overview of morphometrics, including the historical background and the main steps in the morphometric analysis of leaves together with a number of applications. The core of the book focuses on novel diagnostic methods for plant species identification developed from a computer scientist’s perspective. It then concludes with a chapter on the characterization of botanists' visions, which highlights important cognitive aspects that can be implemented in a computer system to more accurately replicate the human expert’s fixation process. The book not only represents an authoritative guide to advanced computational tools fo...

  3. Distribution of Vulpia species (Poaceae in Poland

    Directory of Open Access Journals (Sweden)

    Ludwik Frey

    2011-01-01

    Full Text Available The distribution of four species of the genus Vulpia [V. myuros (L. C.C. Gmel., V. bromoides (L. S.F. Gray, V. ciliata Dumort. and V. geniculata (L. Link] reported in Poland has been studied. Currently, V. myuros and especially V. bromoides are very rare species, and their greatest concentration can be found only in the Lower Silesia region. The number of their localities decreased after 1950 and it seems resonable to include both species in the "red list" of threatened plants in Poland: V. myuros in the EN category, V. bromoides in the CR category. V. ciliata and V. geniculata are very rare ephemerophytes and their localities not confirmed during ca 60 years are of historical interest only.

  4. Babesia species in questing Ixodes ricinus, Sweden.

    Science.gov (United States)

    Karlsson, Maria E; Andersson, Martin O

    2016-02-01

    Babesiosis is an emerging tick-transmitted zoonosis in large parts of the world. In Sweden, the occurrence and diversity of Babesia species is largely unknown. In order to estimate the exposure to Babesia from infected ticks, we collected questing Ixodes ricinus from several sites across southern Sweden during two consecutive field seasons and investigated the occurrence of Babesia species. We report for the first time the occurrence of the zoonotic species Babesia venatorum in Swedish ticks, with a prevalence of 1%. We also detected B. microti (prevalence 3.2%) and B. divergens (prevalence 0.2%). The incidence of Babesia in questing ticks is substantially lower than that of several other tick-borne diseases in Sweden. Nevertheless, babesiosis should not be neglected as a possible diagnosis following tick bites in humans and animals in Sweden.

  5. The hemibiotrophic lifestyle of Colletotrichum species.

    Science.gov (United States)

    Münch, Steffen; Lingner, Ulrike; Floss, Daniela S; Ludwig, Nancy; Sauer, Norbert; Deising, Holger B

    2008-01-01

    Colletotrichum species infect several economically important crop plants. To establish a compatible parasitic interaction, a specialized infection cell, the melanized appressorium, is differentiated on the cuticle of the host. After penetration, an infection vesicle and primary hyphae are formed. These structures do not kill the host cell and show some similarities with haustoria formed by powdery mildews and rust fungi. Therefore, this stage of infection is called biotrophic. Later in the infection process, necrotrophic secondary hyphae spread within and kill the host tissue. The lifestyle of Colletotrichum species is called hemibiotrophic, as biotrophic and necrotrophic developmental stages are sequentially established. As most Colletotrichum species are accessible to molecular techniques, genes can be identified and functionally characterized. Here we demonstrate that Agrobacterium tumefaciens-mediated transformation is a well-suited method for tagging of genes mediating compatibility in the Colletotrichum graminicola-maize interaction.

  6. Enzyme production by species of Cephalosporium.

    Science.gov (United States)

    PISANO, M A; OLENIACZ, W S; MASON, R T; FLEISCHMAN, A I; VACCARO, S E; CATALANO, G R

    1963-03-01

    The culture filtrates of ten species of Cephalosporium, which had been grown under conditions of submerged culture, were tested for enzymatic activity against each of seven substrates. The latter included casein, gelatin, milk, hemoglobin, human plasma clots, starch, and N-acetyl-beta-D-glucosaminide. All organisms tested were active, but to varying degrees. The most pronounced activities were obtained against the proteinaceous substrates. Two unidentified species of Cephalosporium exhibited the highest over-all activities, but no one organism predominated for all enzymatic functions. The ability of a filtrate to degrade a specific substrate was not always correlated with its ability to attack other substrates. The fibrinolytic properties of three of the cephalosporia were of particular interest. alpha-Amylase activity was not significant. The results obtained suggest the possible use of selected species of Cephalosporium as sources of a variety of microbial enzymes.

  7. Forms and genesis of species abundance distributions

    Directory of Open Access Journals (Sweden)

    Evans O. Ochiaga

    2015-12-01

    Full Text Available Species abundance distribution (SAD is one of the most important metrics in community ecology. SAD curves take a hollow or hyperbolic shape in a histogram plot with many rare species and only a few common species. In general, the shape of SAD is largely log-normally distributed, although the mechanism behind this particular SAD shape still remains elusive. Here, we aim to review four major parametric forms of SAD and three contending mechanisms that could potentially explain this highly skewed form of SAD. The parametric forms reviewed here include log series, negative binomial, lognormal and geometric distributions. The mechanisms reviewed here include the maximum entropy theory of ecology, neutral theory and the theory of proportionate effect.

  8. Alien Plant Species Mountain Endemic Tree Species in Gunung Gede Pangrango National Park

    Directory of Open Access Journals (Sweden)

    Budi Utomo

    2012-09-01

    Full Text Available 800x600 Up to now, montane rain forest of Gunung Gede-Pangrango National Park, faces problem in the form of invasion of exotic plant species into the area.  Location of the area that borders with various land uses, such as Botanical Garden and agricultural land, make it very susceptible toward invasion of plant species from outside the area.  The collapse of large trees which normally constitute a mechanism of natural regeneration, was in fact stimulating the development of exotic species, particularly those which were invasive, inside the area. The objective of this research was to test the competitive ability of endemic species, which in this case was represented by Cleystocalyx operculata and Mischocarpus pentapetalus, toward exotic plant species, represented by Austroeupatoriun inulaefolium and Passiflora ligularis, during 5 months of study.  Growth rate of exotic plant species, as well as the dry weight biomass, were larger than those of endemic species.  Indirect estimation of competitive ability showed that competitive ability (β of endemic species were 4-5 times less, namely 0.0274 (for C. operculata and 0.0251 (for M. pentapetalus; as compared with those of exotic species, namely 0.125 (for P. ligularis and 0.1104 (for A. inulaefolium.  Direct test also proved that competitive ability (β of endemic species was lower than that of exotic species, as shown by relative crowding value   Estimation of future competitive ability, using diagram of input/ output ratio, showed also the disability of endemic species to compete with exotic species, where position of input/output ratio points were parallel with equilibrium line y=x. Considering those facts, there is urgent need for controlling these invasive exotic species inside the National Park area to maintain the sustainability of biodiversity and regeneration of endemic species in montane rain forest of Gunung Gede–Pangrango National Park.    Keywords: endemic, exotic, invasion

  9. Discovering the recondite secondary metabolome spectrum of Salinispora species: a study of inter-species diversity.

    Directory of Open Access Journals (Sweden)

    Utpal Bose

    Full Text Available Patterns of inter-species secondary metabolite production by bacteria can provide valuable information relating to species ecology and evolution. The complex nature of this chemical diversity has previously been probed via directed analyses of a small number of compounds, identified through targeted assays rather than more comprehensive biochemical profiling approaches such as metabolomics. Insights into ecological and evolutionary relationships within bacterial genera can be derived through comparative analysis of broader secondary metabolite patterns, and this can also eventually assist biodiscovery search strategies for new natural products. Here, we investigated the species-level chemical diversity of the two marine actinobacterial species Salinispora arenicola and Salinispora pacifica, isolated from sponges distributed across the Great Barrier Reef (GBR, via their secondary metabolite profiles using LC-MS-based metabolomics. The chemical profiles of these two species were obtained by UHPLC-QToF-MS based metabolic profiling. The resultant data were interrogated using multivariate data analysis methods to compare their (biochemical profiles. We found a high level of inter-species diversity in strains from these two bacterial species. We also found rifamycins and saliniketals were produced exclusively by S. arenicola species, as the main secondary metabolites differentiating the two species. Furthermore, the discovery of 57 candidate compounds greatly increases the small number of secondary metabolites previously known to be produced by these species. In addition, we report the production of rifamycin O and W, a key group of ansamycin compounds, in S. arenicola for the first time. Species of the marine actinobacteria harbour a much wider spectrum of secondary metabolites than suspected, and this knowledge may prove a rich field for biodiscovery as well as a database for understanding relationships between speciation, evolution and chemical

  10. Scale-dependent effects of habitat area on species interaction networks: invasive species alter relationships

    Directory of Open Access Journals (Sweden)

    Sugiura Shinji

    2012-07-01

    Full Text Available Abstract Background The positive relationship between habitat area and species number is considered a fundamental rule in ecology. This relationship predicts that the link number of species interactions increases with habitat area, and structure is related to habitat area. Biological invasions can affect species interactions and area relationships. However, how these relationships change at different spatial scales has remained unexplored. We analysed understory plant–pollinator networks in seven temperate forest sites at 20 spatial scales (radius 120–2020 m to clarify scale-associated relationships between forest area and plant–pollinator networks. Results The pooled data described interactions between 18 plant (including an exotic and 89 pollinator (including an exotic species. The total number of species and the number of interaction links between plant and pollinator species were negatively correlated with forest area, with the highest correlation coefficient at radii of 1520 and 1620 m, respectively. These results are not concordant with the pattern predicted by species–area relationships. However, when associations with exotic species were excluded, the total number of species and the number of interaction links were positively correlated with forest area (the highest correlation coefficient at a radius of 820 m. The network structure, i.e., connectance and nestedness, was also related to forest area (the highest correlation coefficients at radii of 720–820 m, when associations with exotics were excluded. In the study area, the exotic plant species Alliaria petiolata, which has invaded relatively small forest patches surrounded by agricultural fields, may have supported more native pollinator species than initially expected. Therefore, this invasive plant may have altered the original relationships between forest area and plant–pollinator networks. Conclusions Our results demonstrate scale-dependent effects of forest

  11. Assessment of weed species composition and species diversity in some fruit orchards

    Directory of Open Access Journals (Sweden)

    Patience Olorunmaiye

    2013-05-01

    Full Text Available Fruits are often perennial crops and therefore can be invaded by weeds at many different times of the year because of their varied life-cycle. Thus a weed survey was conducted in some fruit orchards containing guava/soursop, mango, irvingia and plantain/banana at the National Horticultural Research Institute (NIHORT Ibadan in 2009 cropping season to determine weed species composition and species diversity. Weeds were sampled from each fruit orchard with a 0.5m × 0.5m wooden quadrat, identified to species level, counted and recorded. Data collected were used to calculate relative frequency, relative density and importance relative value for each species. Result shows that 45 weed species were encountered in all the fruit orchards and mango orchard had the highest species diversity (33 species while the least was recorded in guava/soursop orchard (10 species. All these 10 species had their relative frequencies > 5% out of which Ageratum conyzoides > Panicum maximum > Cyperus esculentus > Chromolaena odorata > Commelina erecta are of ecological importance. Three weed species: Ageratum conyzoides, Centrosema pubescens and Panicum maximum associated with all the fruit orchards in all the locations and T. procumbens was the most abundant and most dominant species in guava/soursop, irvingia and plantain/banana orchards while Echinocloa phyllopogon followed the same trend in mango orchard. These weeds are low-growing plants and regular weeding before seed formation will help to reduce their abundance in these orchards so that they do not interfere with harvesting of these fruits.

  12. AFLP variation in 25 Avena species.

    Science.gov (United States)

    Fu, Yong-Bi; Williams, David J

    2008-08-01

    Current molecular characterization of ex situ plant germplasm has placed more emphasis on cultivated gene pools and less on exotic gene pools representing wild relative species. This study attempted to characterize a selected set of germplasm accessions representing various Avena species with the hope to establish a reference set of exotic oat germplasm for oat breeding and research. The amplified fragment length polymorphism (AFLP) technique was applied to screen 163 accessions of 25 Avena species with diverse geographic origins. For each accession, 413 AFLP polymorphic bands detected by five AFLP primer pairs were scored. The frequencies of polymorphic bands ranged from 0.006 to 0.994 and averaged 0.468. Analysis of molecular variance revealed 59.5% of the total AFLP variation resided among 25 oat species, 45.9% among six assessed sections of the genus, 36.1% among three existing ploidy levels, and 50.8% among eight defined genome types. All the species were clustered together according to their ploidy levels. The C genome diploids appeared to be the most distinct, followed by the Ac genome diploid A. canariensis. The Ac genome seemed to be the oldest in all the A genomes, followed by the As, Al and Ad genomes. The AC genome tetraploids were more related to the ACD genome hexaploids than the AB genome tetraploids. Analysis of AFLP similarity suggested that the AC genome tetraploid A. maroccana was likely derived from the Cp genome diploid A. eriantha and the As genome diploid A. wiestii, and might be the progenitor of the ACD genome hexaploids. These AFLP patterns are significant for our understanding of the evolutionary pathways of Avena species and genomes, for establishing reference sets of exotic oat germplasm, and for exploring new exotic sources of genes for oat improvement.

  13. Penicillium species present in Uruguayan salami.

    Science.gov (United States)

    Galvalisi, Umberto; Lupo, Sandra; Piccini, Juan; Bettucci, Lina

    2012-01-01

    The surface coverage of certain dry fermented sausages such as Italian salami by some species of Penicillium provides their characteristic flavor and other beneficial properties. One of them is the protective effect by means of a uniform film of white mold against undesirable microorganisms. The aim of this work was to identify and to isolate the fungal species present in mature Italian type of salami and to evaluate if it is possible to obtain some of them as starters. In addition, the effects of temperature (14 °C and 25 °C), water activity (a w) (0.90, 0.95 and 0.995) and 2.5 % sodium chloride (NaCl) on fungal growth were determined. Similarly, the proteolytic and lipolytic activity and the ability to produce toxic secondary metabolites were evaluated in order to characterize some possible starter strain. All species found belong to the genus Penicillium, including a performing starter as Penicillium nalgiovense and some potentially toxicogenic species. All the strains showed a higher growth rate at 25 °C. The production of extracellular proteases and lipases was significantly higher at 25 °C than at 14 °C with and without sodium chloride. Only Penicillium expansum produced patulin. On the other hand, Penicillium griseofulvum was the only species that produced ciclopiazonic acid but none of the strains produced penicillin. The species present on salami, Penicillium nalgiovense, Penicillium minioluteum, Penicillium brevicompactum and Penicillium puberulum were unable to produce any of the evaluated toxins. These findings suggest that some fungal isolates from the surface of salami such as P. nalgiovense are potentially useful as starters in sausage manufacture.

  14. Egyptian plant species as new ozone indicators

    Energy Technology Data Exchange (ETDEWEB)

    Madkour, S.A.; Laurence, J.A

    2002-12-01

    Of more than 30 species of plants from Egypt screened for sensitivity to ozone, four were found to be suitable for use as bioindicators. - The aim of this study was to test and select one or more highly sensitive, specific and environmentally successful Egyptian bioindicator plants for ozone (O{sub 3}). For that purpose more than 30 Egyptian species and cultivars were subjected to extensive screening studies under controlled environmental and pollutant exposure conditions to mimic the Egyptian environmental conditions and O{sub 3} levels in urban and rural sites. Four plant species were found to be more sensitive to O{sub 3} than the universally used O{sub 3}-bioindicator, tobacco Bel W3, under the Egyptian environmental conditions used. These plant species, jute (Corchorus olitorius c.v. local), clover (Trifolium alexandrinum L. c.v. Masry), garden rocket (Eruca sativa c.v. local) and alfalfa (Medicago sativa L. c.v. local), ranked in order of decreasing sensitivity, exhibited typical O{sub 3} injury symptoms faster and at lower O{sub 3} concentrations than Bel W3. Three variables were tested in search of a reliable tool for the diagnosis and prediction of O{sub 3} response prior to the appearance of visible foliar symptoms: pigment degradation, stomatal conductance (g{sub s}) and net photosynthetic CO{sub 2} assimilation (P{sub net}). Pigment degradation was found to be unreliable in predicting species sensitivity to O{sub 3}. Evidence supporting stomatal conductance involvement in O{sub 3} tolerance was found only in tolerant species. A good correlation was found between g{sub s}, restriction of O{sub 3} and CO{sub 2} influx into the mesophyll tissues, and P{sub net}. Changes in P{sub net} seemed to depend largely on fluctuations in g{sub s}.

  15. Combinatorial Cis-regulation in Saccharomyces Species

    Directory of Open Access Journals (Sweden)

    Aaron T. Spivak

    2016-03-01

    Full Text Available Transcriptional control of gene expression requires interactions between the cis-regulatory elements (CREs controlling gene promoters. We developed a sensitive computational method to identify CRE combinations with conserved spacing that does not require genome alignments. When applied to seven sensu stricto and sensu lato Saccharomyces species, 80% of the predicted interactions displayed some evidence of combinatorial transcriptional behavior in several existing datasets including: (1 chromatin immunoprecipitation data for colocalization of transcription factors, (2 gene expression data for coexpression of predicted regulatory targets, and (3 gene ontology databases for common pathway membership of predicted regulatory targets. We tested several predicted CRE interactions with chromatin immunoprecipitation experiments in a wild-type strain and strains in which a predicted cofactor was deleted. Our experiments confirmed that transcription factor (TF occupancy at the promoters of the CRE combination target genes depends on the predicted cofactor while occupancy of other promoters is independent of the predicted cofactor. Our method has the additional advantage of identifying regulatory differences between species. By analyzing the S. cerevisiae and S. bayanus genomes, we identified differences in combinatorial cis-regulation between the species and showed that the predicted changes in gene regulation explain several of the species-specific differences seen in gene expression datasets. In some instances, the same CRE combinations appear to regulate genes involved in distinct biological processes in the two different species. The results of this research demonstrate that (1 combinatorial cis-regulation can be inferred by multi-genome analysis and (2 combinatorial cis-regulation can explain differences in gene expression between species.

  16. Rare and little known Collembola species from Hungary

    Directory of Open Access Journals (Sweden)

    Winkler, D.

    2012-07-01

    Full Text Available Two species, Pseudosinella bohemica Rusek, 1979 and Folsomides marchicus (Frenzel, 1941 are recorded from Hungary, the latter species for the first time. An illustrated morphological description of the two species is presented.

  17. Variation in biofouling on different species of Indian timbers

    Digital Repository Service at National Institute of Oceanography (India)

    Raveendran, T.V.; Wagh, A.B.

    Biofouling on twenty species of wood exposed in waters of Mormugao Harbour, Goa, India have been presented. Macrofouling biomass varied from species to species. Maximum biomass was recorded on Artocarpus chaplasha (4 kg/m2) and minimum on Hopea...

  18. Genetic factors in Threatened Species Recovery Plans on three continents

    Science.gov (United States)

    Threatened species' recovery planning is applied globally to stem the current species extinction crisis. Evidence supports a key role of genetic processes, such as inbreeding depression, in determining species viability. We examined whether genetic factors are considered in threa...

  19. U.S. Geological Survey Gap Analysis Program Species Ranges

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — GAP species range data show a coarse representation of the total areal extent of a species or the geographic limits within which a species can be found (Morrison...

  20. A new species of Begonia (Begoniaceae from South Sulawesi, Indonesia.

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    Harry Wiriadinata

    2013-12-01

    Full Text Available A new species, Begonia hooveriana Wiriad., is described from Tanah Toraja in South Sulawesi. It belongs to Begonia section Petermannia and brings the total number of Begonia species native to Sulawesi to 43 species

  1. 40 CFR 230.30 - Threatened and endangered species.

    Science.gov (United States)

    2010-07-01

    .... (a) An endangered species is a plant or animal in danger of extinction throughout all or a significant portion of its range. A threatened species is one in danger of becoming an endangered species in...

  2. U.S. Geological Survey Gap Analysis Program Species Ranges

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — GAP species range data show a coarse representation of the total areal extent of a species or the geographic limits within which a species can be found (Morrison and...

  3. Aquatic invasive species: Lessons from cancer research

    Science.gov (United States)

    Sepulveda, Adam; Ray, Andrew; Al-Chokhachy, Robert K.; Muhlfeld, Clint C.; Gresswell, Robert E.; Gross, Jackson A.; Kershner, Jeffrey L.

    2014-01-01

    Aquatic invasive species are disrupting ecosystems with increasing frequency. Successful control of these invasions has been rare: Biologists and managers have few tools for fighting aquatic invaders. In contrast, the medical community has long worked to develop tools for preventing and fighting cancer. Its successes are marked by a coordinated research approach with multiple steps: prevention, early detection, diagnosis, treatment options and rehabilitation. The authors discuss how these steps can be applied to aquatic invasive species, such as the American bullfrog (Lithobates catesbeianus), in the Northern Rocky Mountain region of the United States, to expedite tool development and implementation along with achievement of biodiversity conservation goals.

  4. Cross-species transmission of CWD prions.

    Science.gov (United States)

    Kurt, Timothy D; Sigurdson, Christina J

    2016-01-01

    Prions cause fatal neurodegenerative diseases in humans and animals and can be transmitted zoonotically. Chronic wasting disease (CWD) is a highly transmissible prion disease of wild deer and elk that affects cervids over extensive regions of the United States and Canada. The risk of cross-species CWD transmission has been experimentally evaluated in a wide array of mammals, including non-human primates and mouse models expressing human cellular prion protein. Here we review the determinants of cross-species CWD transmission, and propose a model that may explain a structural barrier for CWD transmission to humans.

  5. FEATURES DIGESTION OF STURGEON SPECIES (ACIPENSERIDAE (REVIEW

    Directory of Open Access Journals (Sweden)

    M. Simon

    2016-09-01

    Full Text Available Purpose. To review scientific sources are about the anatomical, physiological and biochemical characteristics of the digestive system and proper digestion process in the sturgeon species (Acipenseridae. Outline the common anatomical and morphological characteristics of the gastrointestinal tract. Consider the activity of digestive enzymes and the influence of various factors. Findings. Review of scientific papers reveals that although the digestion of sturgeon are broadly similar to those of the cartilaginous and bony fish, there are a number of species specificity. In particular, sturgeon enzymes have a wider temperature and hydrogen ranges. It is confirmed that temperature adaptations of digestive system poikilothermic organ-isms are realised mainly thanks to reorganisations of fermental systems. It is shown that enzymes in sturgeons are adjustable, as their activity level significantly changes under the influence of divalent metal ions (Mn2+, Fe2+, Co2+, Ni2+, Cu2+, Zn2+. The assumption that evolutionary adaptation of hydrolytic function of intestines of fishes to temperature conditions of an inhabitancy takes place, apparently, is made. The paper describes the effect of sex and age factors on the level of activity of enzymes of sturgeons. Set out the regularities of circadian rhythms of the fish of this family. Showed specific features of the liver and its involvement in lipid metabolism and antioxidant defense system. Practical value. The knowledge of hydrolysis characteristics of a diet of sturgeon species is important for the efficiency estimation of feeding and understanding of evolutionary and ecological aspects of digestion physiology. Systematized data on the digestive system of fish sturgeon species are of interest a wide range of research in two main areas. Firstly, although the sturgeon are relict species, but the adaptation of their digestive system is still going on, allowing you to analyze the evolutionary development of the

  6. Anaplasma species of veterinary importance in Japan

    Directory of Open Access Journals (Sweden)

    Adrian Patalinghug Ybañez

    2016-11-01

    Full Text Available Anaplasma species of the family Anaplasmataceae, order Rickettsiales are tick-borne organisms that can cause disease in animals and humans. In Japan, all recognized species of Anaplasma (except for Anaplasma ovis and a potentially novel Anaplasma sp. closely related to Anaplasma phagocytophilum have been reported. Most of these detected tick-borne pathogens are believed to be lowly pathogenic in animals in Japan although the zoonotic A. phagocytophilum has recently been reported to cause clinical signs in a dog and in humans. This review documents the studies and reports about Anaplasma spp. in Japan.

  7. Anaplasma species of veterinary importance in Japan

    Science.gov (United States)

    Ybañez, Adrian Patalinghug; Inokuma, Hisashi

    2016-01-01

    Anaplasma species of the family Anaplasmataceae, order Rickettsiales are tick-borne organisms that can cause disease in animals and humans. In Japan, all recognized species of Anaplasma (except for Anaplasma ovis) and a potentially novel Anaplasma sp. closely related to Anaplasma phagocytophilum have been reported. Most of these detected tick-borne pathogens are believed to be lowly pathogenic in animals in Japan although the zoonotic A. phagocytophilum has recently been reported to cause clinical signs in a dog and in humans. This review documents the studies and reports about Anaplasma spp. in Japan. PMID:27956767

  8. Species, Distributions and Conservation of Acipenseriformes

    Institute of Scientific and Technical Information of China (English)

    黄大明

    2002-01-01

    A list of the world-wide distribution of Acipenseriformes is given including 32 species and subspecies, their distributions, and conservation levels. Most of the species and subspecies of sturgeons are threatened or endangered in at least some of their habitats. Many are nearing extinction. The threat against sturgeons will continue to grow as the world's population increases. Therefore, the problem of conserving sturgeons and replenishing their stock in the entire range has become urgent for scientists of various countries. Materials given here will be useful for solving this difficult but important problem. The problems concerning the Acipenseridae, such as the investigation of resource classification and biological conservation, are also discussed.

  9. A new dimension in documenting new species

    DEFF Research Database (Denmark)

    Akkari, Nesrine; Enghoff, Henrik; Metscher, Brian D.

    2015-01-01

    We review the state-of-the-art approaches currently applied in myriapod taxonomy, and we describe, for the first time, a new species of millipede (Ommatoiulus avatar n. sp., family Julidae) using high-resolution X-ray microtomography (microCT) as a substantive adjunct to traditional morphological...... examination. We present 3D models of the holotype and paratype specimens and discuss the potential of this non-destructive technique in documenting new species of millipedes and other organisms. The microCT data have been uploaded to an open repository (Dryad) to serve as the first actual millipede cybertypes...

  10. New species of scytonema agardh (Cyanophyta)

    CSIR Research Space (South Africa)

    Welsh, H

    1963-01-01

    Full Text Available ? ,,~ ~ W3 A NEW SPECIES OF SCYTONEMA AGARDH (CYANDPHYTA) SEPARATA DR ELEVISTA DE I3IOLOGIA 3 (2?4): 227-232 1963 REVISTA DE B1OLOGjLA~ REVISTA BRASILEIRA E PORTUGUESA DE BIOLOGIA EM GERAL \\T~j 3 1952-63 N? 2-4 -I INDICE* F. R~sryoi? ? A... New Species of I-Iydrocoryne Schzoabe and Anabaena Bory. Revista de Biologia, 2 (3-4): pp. 257-260. 1962 Some New Cyatiophyles front Soul/inn Africa. Revue Algologique, N.? 3, Octobre, Paris. REVISTA DE BIOLOGIA A J?evista de Bioloqia d uma revista...

  11. Impacts of Species Interactions on Atmospheric Processes

    Science.gov (United States)

    Lerdau, M.; Wang, B.; Cook, B.; Neu, J. L.; Schimel, D.

    2016-12-01

    The current fascination with interactions between air quality and ecosystems began over 60 years ago with the discovery by Arie Haagen-Smit and colleagues that organic carbon emissions from plants play a role in ozone formation. In the seven decades since, thanks to biochemical and physiological studies of these emissions, their biosynthetic pathways and short-term flux-regulation mechanisms are now well understood. This `metabolic' approach has been invaluable for developing models of VOC emissions and atmospheric oxidant dynamics that function on local spatial scales over time intervals of minutes to days, but it has been of limited value for predicting emissions across larger spatial and temporal scales. This limited success arises in large part from the species-specific nature of volatile organic carbon production by plants. Each plant species produces certain volatile compounds but not others, so predicting emissions through time requires consideration of plant species composition. As the plant species composition of an ecosystem changes through time, so too do its VOC emissions. When VOC impacts on the atmosphere influence species composition by altering inter-specific interactions, there exists the possibility for feedbacks among emissions, atmospheric chemistry, higher order ecological processes such as competition & pollination, and species composition. For example, previous work has demonstrated that VOC emissions may affect ozone, which, in turn, alters competition among trees species, and current efforts suggest that plant reproductive success may be mediated by ozone impacts on floral signals. These changes in ecological processes alter the species composition and future VOC emissions from ecosystems. We present empirical and simulated data demonstrating that biological diversity may be affected by VOC impacts on the atmosphere and that these diversity changes may, in turn, alter the emissions of VOC's and other photochemically active compounds to the

  12. Applications of species distribution modeling to paleobiology

    DEFF Research Database (Denmark)

    Svenning, J.-C.; Fløjgaard, Camilla; A. Marske, Katharine

    2011-01-01

    Species distribution modeling (SDM: statistical and/or mechanistic approaches to the assessment of range determinants and prediction of species occurrence) offers new possibilities for estimating and studying past organism distributions. SDM complements fossil and genetic evidence by providing (i...... the role of Pleistocene glacial refugia in biogeography and evolution, especially in Europe, but also in many other regions. SDM-based approaches are also beginning to contribute to a suite of other research questions, such as historical constraints on current distributions and diversity patterns, the end...

  13. Electrophoretic karyotypes of some related Mucor species.

    Science.gov (United States)

    Nagy, A; Palagyi, Z; Vastag, M; Ferenczy, L; Vágvölgyi, C

    2000-07-01

    Contour clamped homogeneous electric field (CHEF) gel electrophoresis was used to obtain electrophoretic karyotypes from nine Mucor strains representing five different species (M. bainieri, M. circinelloides, M. mucedo, M. plumbeus and M. racemosus). The chromosomal banding patterns revealed high variability among the isolates. The sizes of the DNA in the Mucor chromosomes were estimated to be between 2.5 and 8.7 Mb. The total genome sizes were calculated to be between 30.0 and 44.7 Mb. The applicability of these electrophoretic karyotypes for the investigation of genome structure, for strain identification and for species delimitation is considered.

  14. Hypoxylon species on beech and other broadleaves

    Directory of Open Access Journals (Sweden)

    Milijašević Tanja

    2004-01-01

    Full Text Available Fungi in the genus Hypoxylon cause wood decay and most of them are saprophytes on dead wood or parasites of weakness. The following species in this genus were identified in this study performed at several localities in Serbia and Montenegro: H. deustum, H. fragiforme, H. nummularium, H. multiforme, H. rubiginosum and H. fuscum. Among them the most significant species is H. deustum, the fungus causing root and butt rot of standing beech trees. It was recorded from all coppice and high forests of beech. This paper presents the morphological characteristics of the recorded fungi their range, plant hosts and significance.

  15. Conidial anastomosis fusion between Colletotrichum species.

    Science.gov (United States)

    Roca, Maria Gabriela; Davide, Lisete C; Davide, Livia M C; Mendes-Costa, Maria C; Schwan, Rosane F; Wheals, Alan E

    2004-11-01

    Colletotrichum lindemuthianum is a pathogen of the common bean plant (Phaseolus vulgaris) causing anthracnose. Large numbers of isolates can rapidly arise with different genetic and chromosomal compositions but their origin is unknown since sexual fruit bodies have only been found in the laboratory. We have recently described the occurrence of special kinds of hyphae that create anastomoses directly between conidia. In this work we show that conidial anastomoses can occur between two different Colletotrichum species. The implications of this observation on the generation of genetic diversity in these species are discussed.

  16. Rhizidium phycophilum, a new species in Chytridiales.

    Science.gov (United States)

    Picard, Kathryn T; Letcher, Peter M; Powell, Martha J

    2009-01-01

    Molecular and ultrastructural investigations are revealing unrealized diversity among chytrids as the taxonomic revision of order Chytridiales (Chytridiomycota) progresses. During a biodiversity survey of soil-inhabiting chytrids in Australia an undescribed chytrid was isolated from a soil sample collected in a cool temperate rainforest of New South Wales, Australia. Combined zoospore ultrastructure analysis and molecular phylogenetic analyses of partial LSU rRNA and ITS1-5.8S-ITS2 sequences demonstrated this chytrid was a new species within Chytridiales and possessed distinctive zoospore architecture previously unknown. Herein we delineate a new Rhizidium species in Chytridiales based on molecular monophyly and unique subcellular organization of the zoospore.

  17. A new alamellate Hygrocybe species from Ecuador

    DEFF Research Database (Denmark)

    Læssøe, Thomas; Boertmann, David

    2008-01-01

    The first known species of Hygrocybe with a smooth hymenophore is described based on material from the eastern slopes of Andean Ecuador. It is considered as incertae sedis in the genus due to a lack of conclusive morphological characters and in the absence of sequence data.......The first known species of Hygrocybe with a smooth hymenophore is described based on material from the eastern slopes of Andean Ecuador. It is considered as incertae sedis in the genus due to a lack of conclusive morphological characters and in the absence of sequence data....

  18. DNA barcoding: species delimitation in tree peonies

    Institute of Scientific and Technical Information of China (English)

    ZHANG JinMei; WANG JianXiu; XIA Tao; ZHOU ShiLiang

    2009-01-01

    Delimitations of species are crucial for correct and precise identification of taxa. Unfortunately "spe-cies" is more a subjective than an objective concept in taxonomic practice due to difficulties in re-vealing patterns of infra- or inter-specific variations. Molecular phylogenetic studies at the population level solve this problem and lay a sound foundation for DNA barcoding. In this paper we exemplify the necessity of adopting a phylogenetic concept of species in DNA barcoding for tree peonies (Paeonia sect. Moutan). We used 40 samples representing all known populations of rare and endangered species and several populations of widely distributed tree peonies. All currently recognized species and majorbvariants have been included in this study. Four chloroplast gene fragments, I.e. ndhF, rps16-trnQ, trnL.F and trnS-G (a total of 5040 characters, 96 variable and 69 parsimony-informative characters) and one variable and single-copy nuclear GPAT gene fragment (2093-2197 bp, 279 variable and 148 parsi-mony-informative characters) were used to construct phylogenetic relationships among the taxa. The evolutionary lineages revealed by the nuclear gene and the chloroplast genes are inconsistent with the current circumscriptions of P. Decomposita, P. Jishanensis, P. Qiui, and P. Rockii based on morphology. The inconsistencies come from (1) significant chloroplast gene divergence but little nuclear GPAT gene divergence among population systems of P. Decomposita + P. Rockii, and (2) well-diverged nuclear GPAT gene but little chloroplast gene divergence between P. Jishanensis and P. Qiui. The incongruence of the phylogenies based on the chloroplast genes and the nuclear GPAT gene is probably due to the chloro-plast capture event in evolutionary history, as no reproductive barriers exist to prevent inter-specific hybridization. We also evaluated the suitability of these genes for use as DNA barcodes for tree peonies. The variability of chloroplast genes among well

  19. The Scirtothrips perseae species-group (Thysanoptera), with one new species from avocado, Persea americana.

    Science.gov (United States)

    Mound, Laurence A; Hoddle, Mark S

    2016-02-12

    Following recent molecular studies on avocado thrips, a new species is described from Costa Rica, Ecuador, and Colombia from the young leaves of avocado, Persea americana. Scirtothrips hansoni sp.n. is closely related to the Californian pest, S. perseae, and also to S. astrictus from Costa Rica that remains known from a single female. An illustrated key to these three species is provided.

  20. Cryptic speciation in the Acari: a function of species lifestyles or our ability to separate species?

    Science.gov (United States)

    There are approximately 55,000 described Acari species, accounting for almost half of all known Arachnida species, but total estimated Acari diversity is reckoned to be far greater. One important source of currently hidden Acari diversity is cryptic speciation, which poses challenges to taxonomists ...

  1. Cylindrocarpon root rot: multi-gene analysis reveals novel species within the Ilyonectria radicicola species complex

    NARCIS (Netherlands)

    Cabral, A.; Groenewald, J.Z.; Rego, C.; Oliveira, H.; Crous, P.W.

    2012-01-01

    Ilyonectria radicicola and its Cylindrocarpon-like anamorph represent a species complex that is commonly associated with root rot disease symptoms on a range of hosts. During the course of this study, several species could be distinguished from I. radicicola sensu stricto based on morphological and

  2. Species composition of a soil invertebrate multi-species test system determines the level of ecotoxicity

    DEFF Research Database (Denmark)

    Sechi, Valentina; D'Annibale, Alessandra; Maraldo, Kristine

    2014-01-01

    A soil multi-species, SMS, experimental test system consisting of the natural microbial community, five collembolan species and a predatory mite along with either Enchytraeus crypticus or the earthworm Eisenia fetida were exposed to α-cypermethrin. A comparison of the performance of these two types...

  3. Spectral variability within species and its effects on savanna tree species discrimination

    NARCIS (Netherlands)

    Cho, M.A.; Debba, P.; Mathieu, R.; Aardt, van J.; Asner, G.P.; Naidoo, L.; Main, R.; Ramoelo, A.; Majeke, B.

    2009-01-01

    Differences in within-species phenology and structure driven by factors including topography, edaphic properties, and climatic variables present important challenges for species differentiation with remote sensing in the Kruger National Park, South Africa. The objective of this study was to examine

  4. Invasive Species Science Branch: research and management tools for controlling invasive species

    Science.gov (United States)

    Reed, Robert N.; Walters, Katie D.

    2015-01-01

    Invasive, nonnative species of plants, animals, and disease organisms adversely affect the ecosystems they enter. Like “biological wildfires,” they can quickly spread and affect nearly all terrestrial and aquatic ecosystems. Invasive species have become one of the greatest environmental challenges of the 21st century in economic, environmental, and human health costs, with an estimated effect in the United States of more than $120 billion per year. Managers of the Department of the Interior and other public and private lands often rank invasive species as their top resource management problem. The Invasive Species Science Branch of the Fort Collins Science Center provides research and technical assistance relating to management concerns for invasive species, including understanding how these species are introduced, identifying areas vulnerable to invasion, forecasting invasions, and developing control methods. To disseminate this information, branch scientists are developing platforms to share invasive species information with DOI cooperators, other agency partners, and the public. From these and other data, branch scientists are constructing models to understand and predict invasive species distributions for more effective management. The branch also has extensive herpetological and population biology expertise that is applied to harmful reptile invaders such as the Brown Treesnake on Guam and Burmese Python in Florida.

  5. Cross-species amplification of 105 Lolium perenne SSR loci in 23 species within the Poaceae

    DEFF Research Database (Denmark)

    Jensen, Louise Bach; Holm, Preben Bach; Lübberstedt, Thomas

    2007-01-01

    Amplification of 105 Lolium perenne SSR markers was studied in 23 grass species representing seven tribes from three subfamilies of Poaceae. Twelve of the SSR markers are published for the first time. Between 2% and 96% of the SSR markers could be amplified within a given species. A subset of eight...

  6. Biodiversity of Asterina species on Neotropical host plants: new species and records from Panama.

    Science.gov (United States)

    Hofmann, T A; Piepenbring, M

    2011-01-01

    Two new species of the genus Asterina are described from living leaves collected in provinces Chiriquí and Bocas del Toro in western Panama. Asterina alloplecti on Alloplectus ichtyoderma (Gesneriaceae) differs from other Asterina on Gesneriaceae by its stalked appressoria and host relationship. Asterina compsoneurae on Compsoneura sprucei (Myristicaceae) can be distinguished from other members of Asterina on Myristicaceae by its larger ascomata, larger, prominently spinose ascospores and host relationship. New records for Panama are Asterina corallopoda from a new host plant species (Solanum trizygum, Solanaceae), A. diplopoda, A. ekmanii from a new host plant species (Gonzalagunia rudis, Rubiaceae), A. siphocampyli from a new host plant genus and species (Burmeistera vulgaris, Campanulaceae) and A. styracina from a new host-plant species (Styrax argenteus, Styracaceae). This study increases the number of species of Asterina known for Panama from 12 to 19 and the number of Asterinaceae from 14 to 21. Asterina corallopoda, A. diplopoda, A. ekmanii, A. siphocampyli and A. styracina are illustrated for the first time. A phylogeny inferred from the analysis of LSU rDNA sequences of species of Asterina is presented. The diversity and host-plant patterns of known Neotropical species of Asterina are discussed.

  7. Vulnerability of species to climate change in the Southwest: terrestrial species of the Middle Rio Grande

    Science.gov (United States)

    Megan M. Friggens; Deborah M. Finch; Karen E. Bagne; Sharon J. Coe; David L. Hawksworth

    2013-01-01

    We used a vulnerability scoring system to assess the vulnerability of 117 vertebrate species that occur in the Middle Rio Grande Bosque (MRGB) to expected climate change. The purpose of this project was to guide wildlife managers on options and considerations for climate change adaptation. The 117 species occur regularly in the MRGB during the breeding season, winter,...

  8. The relation between unpalatable species, nutrients and plant species richness in Swiss montane pastures.

    NARCIS (Netherlands)

    Kleijn, D.; Muller-Scharer, H.

    2006-01-01

    In agriculturally marginal areas, the control of unpalatable weeds on species rich pastures may become problematic due to agricultural and socio-economic developments. It is unclear how increased dominance of unpalatable species would affect the botanical diversity of these grasslands. We investigat

  9. Cylindrocarpon root rot: multi-gene analysis reveals novel species within the Ilyonectria radicicola species complex

    NARCIS (Netherlands)

    Cabral, A.; Groenewald, J.Z.; Rego, C.; Oliveira, H.; Crous, P.W.

    2012-01-01

    Ilyonectria radicicola and its Cylindrocarpon-like anamorph represent a species complex that is commonly associated with root rot disease symptoms on a range of hosts. During the course of this study, several species could be distinguished from I. radicicola sensu stricto based on morphological and

  10. A new species of the lowland Oligosarcus Günther species group (Teleostei: Ostariophysi: Characidae

    Directory of Open Access Journals (Sweden)

    Naércio Aquino Menezes

    Full Text Available A new characid species is described from the rio Jacuí basin, a coastal drainage from southern Brazil. Itis morphologically most similar to its sympatric congeners Oligosarcus jenynsii and O. jacuiensis , but can be distinguished from both species in having the interorbital region wider and the pectoral fin shorter and additionally from O. jenynsii in having a smaller orbital diameter.

  11. Molecular phylogenetics of geographically restricted Acropora species: implications for threatened species conservation.

    Science.gov (United States)

    Richards, Z T; Miller, D J; Wallace, C C

    2013-12-01

    To better understand the underlying causes of rarity and extinction risk in Acropora (staghorn coral), we contrast the minimum divergence ages and nucleotide diversity of an array of species with different range sizes and levels of threat. Time-calibrated Bayesian analyses based upon concatenated nuclear and mitochondrial sequence data implied contemporary range size and vulnerability are linked to species age. However, contrary to previous hypotheses that suggest geographically restricted Acropora species evolved in the Plio-Pleistocene, the molecular phylogeny depicts some Indo-Australian species have greater antiquity, diverging in the Miocene. Species age is not related to range size as a simple positive linear function and interpreting the precise tempo of evolution in this genus is greatly complicated by morphological homoplasy and a sparse fossil record. Our phylogenetic reconstructions provide new examples of how morphology conceals cryptic evolutionary relationships in this keystone genus, and offers limited support for the species groupings currently used in Acropora systematics. We hypothesize that in addition to age, other mechanisms (such as a reticulate ancestry) delimit the contemporary range of some Acropora species, as evidenced by the complex patterns of allele sharing and paraphyly we uncover. Overall, both new and ancient evolutionary information may be lost if geographically restricted and threatened Acropora species are forced to extinction. In order to protect coral biodiversity and resolve the evolutionary history of staghorn coral, further analyses based on comprehensive and heterogeneous morphological and molecular data utilizing reticulate models of evolution are needed. Copyright © 2013 Elsevier Inc. All rights reserved.

  12. The Quercus feeding Stigmella species of the West Palaearctic: new species, key and distribution (Lepidoptera: Nepticulidae)

    NARCIS (Netherlands)

    Nieukerken, van E.J.; Johansson, R.

    2003-01-01

    The species of the Stigmella ruficapitella group occurring in the Western Palaearctic and feeding on Quercus are reviewed. We recognise 19 species, five of which are described as new: Stigmella fasciata sp. n. on Quercus pubescens from Slovenia, Croatia, Greece and Turkey, S. cocciferae sp. n. on Q.

  13. Spectral variability within species and its effects on savanna tree species discrimination

    NARCIS (Netherlands)

    Cho, M.A.; Debba, P.; Mathieu, R.; Aardt, van J.; Asner, G.P.; Naidoo, L.; Main, R.; Ramoelo, A.; Majeke, B.

    2009-01-01

    Differences in within-species phenology and structure driven by factors including topography, edaphic properties, and climatic variables present important challenges for species differentiation with remote sensing in the Kruger National Park, South Africa. The objective of this study was to examine

  14. Species status and conservation issues of New Zealand's endemic Latrodectus spider species (Araneae: Theridiidae)

    DEFF Research Database (Denmark)

    Vink, Cor J; Sirvid, Phillip J; Malumbres-Olarte, Jagoba

    2008-01-01

    New Zealand has two endemic widow spiders, Latrodectus katipo Powell, 1871 and L. atritus Urquhart, 1890. Both species face many conservation threats and are actively managed. The species status of the Latrodectus spiders of New Zealand was assessed using molecular (COI, ITS1, ITS2...

  15. Cross-species amplification of microsatellite loci developed for Passiflora edulis Sims. in related Passiflora Species

    Directory of Open Access Journals (Sweden)

    Gilmara Alvarenga Fachardo Oliveira

    2013-10-01

    Full Text Available The aim of this study was to evaluate the selected 41 SSR markers developed for yellow passion fruit (Passiflora edulis f. flavicarpa Sims. for their transferability to 11 different Passiflora species. Twenty-one SSR were successfully amplified in 10 wild species of passion fruit producing 101 bands. All the markers were amplifiable for at least one species. The mean transferability was 68,8%, ranging from 15,4% (primer PE11 to 100 % (PE13, PE18, PE37, PE41 and PE88. Transferability was higher for the species from the Passiflora subgenus than for those from the Decaloba and Dysosmia subgenus. The results indicated a high level of nucleotide sequence conservation of the primer regions in the species evaluated, and consequently, they could potentially be used for the establishment of molecular strategies for use in passion fruit breeding and genetics.

  16. Ants Learn Aphid Species as Mutualistic Partners: Is the Learning Behavior Species-Specific?

    Science.gov (United States)

    Hayashi, Masayuki; Nakamuta, Kiyoshi; Nomura, Masashi

    2015-12-01

    In ant-aphid associations, many aphid species provide ants with honeydew and are tended by ants, whereas others are never tended and are frequently preyed upon by ants. In these relationships, ants must have the ability to discriminate among aphid species, with mutualistic aphids being accepted as partners rather than prey. Although ants reportedly use cuticular hydrocarbons (CHCs) of aphids to differentiate between mutualistic and non-mutualistic species, it is unclear whether the ability to recognize mutualistic aphid species as partners is innate or involves learning. Therefore, we tested whether aphid recognition by ants depends on learning, and whether the learning behavior is species-specific. When workers of the ant Tetramorium tsushimae had previously tended the cowpea aphid, Aphis craccivora, they were less aggressive toward this species. In addition, ants also reduced their aggressiveness toward another mutualistic aphid species, Aphis fabae, after tending A. craccivora, whereas ants remained aggressive toward the non-mutualistic aphid, Acyrthosiphon pisum, regardless of whether or not they had previous experience in tending A. craccivora. When ants were offered glass dummies treated with CHCs of these aphid species, ants that had tended A. craccivora displayed reduced aggression toward CHCs of A. craccivora and A. fabae. Chemical analyses showed the similarity of the CHC profiles between A. craccivora and A. fabae but not with A. pisum. These results suggest that aphid recognition of ants involves learning, and that the learning behavior may not be species-specific because of the similarity of CHCs between different aphid species with which they form mutualisms.

  17. Economic Science, Endangered Species and Biodiversity Loss

    NARCIS (Netherlands)

    Bulte, E.H.; Kooten, van G.C.

    2000-01-01

    Although economic analysis can be used to argue for preservation of species and habitats, many natural assets represent inferior investments in society's asset portfolio. We demonstrate this for the case of ancient temperate rainforests and minke whales ( Balaenoptera acutorostrata). For both rainfo

  18. Disposition of recently described species of Penicillium

    NARCIS (Netherlands)

    Frisvad, Jens C.; Samson, Robert A.; Stolk, Amelia C.

    1990-01-01

    Hundred and twenty-two species, varieties, and new combinations of Penicillium, Eupenicillium, and Talaromyces described since 1977 have been studied taxonomically and screened for mycotoxin production. Only 48 taxa could be accepted: Eupenicillium angustiporcatum, E. cryptum, E. lineolatum, E. limo

  19. Some Malesian species of Pouteria (Sapotaceae)

    NARCIS (Netherlands)

    Vink, Wim

    2002-01-01

    Some Malesian species of Pouteria are described or redescribed in view of new or additional material. In some taxa a wide variability is found. It is proposed to accept Pennington’s system of the Sapotaceae as final, because the century-long battle over the systematics of that family has seriously h

  20. Self-thinning in four pine species

    NARCIS (Netherlands)

    Brunet-Navarro, Pau; Sterck, Frank J.; Vayreda, Jordi; Martinez-Vilalta, Jordi; Mohren, Frits

    2016-01-01


    Key message

    Self-thinning lines are species- and climate-specific, and they should be used when assessing the capacity of different forest stands to increase biomass/carbon storage.


    Context

    The capacity of forests to store carbon can help to mitigate the effects