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Sample records for chirostoma humboldtianum atheriniformes

  1. The complete mitochondrial DNA of the endemic shortfin silverside, Chirostoma humboldtianum (Valenciennes, 1835).

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    Barriga-Sosa, Irene de los A; De León, Francisco J García; Del Río-Portilla, Miguel A

    2016-01-01

    The shortfin silverside Chirostoma humboldtianum, is an endemic fish from the Mesa Central of Mexico, it is considered the "ancestral" species of the "peces blancos" and plays an important role as a potential species for aquaculture. Here we sequence its mitogenome (Genbank accession number KJ921739), which has a total length of 16,447 bp, and the arrangement consist of 13 protein-coding genes, 2 ribosomal RNA (rRNA) genes and 22 transfer RNA similar to other Atheriniformes. This mitogenome will be useful for phylogenetic, population and phylogeographic studies of this and other important atherinopsid species. PMID:25185796

  2. Isolation and characterization of microsatellite loci in the Charal de Xochimilco Chirostoma humboldtianum

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    Rosa María García-Martínez; Francisco Javier García-De León; Omar Mejía; Irene de los Ángeles Barriga-Sosa

    2014-01-01

    Microsatellite loci were isolated and characterized for the endemic fish Chirostoma humboldtianum using an enrichment procedure. Eight polymorphic microsatellites were genotyped for 32 - 48 individuals from Tepuxtepec Dam, Michoacán. The number of alleles per locus ranged from 3 to 11 and the average observed and expected heterozygosities were 0.61 and 0.63, respectively. All loci deviated significantly from Hardy-Weinberg expectations, which might be related to small population sizes associa...

  3. Antibiotic and heavy metal resistance of Aeromonas hydrophila isolated from charal (Chirostoma humboldtianum, Valenciannes, 1835)

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    Gloria Luz Paniagua; Eric Monroy; Magdalena Perches; Erasmo Negrete; Octavio García; Sergio Vaca

    2006-01-01

    Antibiotic and heavy metal susceptibilities of twenty Aeromonas hydrophila strains, isolated from the gastrointestinal tract of the charal (Chirostoma humboldtianum), an autochthonous Mexican fish, were analyzed. All strains produced #946;-lactamase and were resistant to penicillin and dicloxacillin, showing single peak for minimum inhibitory concentration (MIC) distributions at 2000-4000 µg/mL and 500-1000 µg/ml, respectively. Ampicillin MIC distribution was bimodal with 20% resistant strai...

  4. Vergleichende Untersuchungen an der Netzhaut von Atheriniformes (Teleostei)

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    Reckel, Frank

    2001-01-01

    Die vorliegende Arbeit stellt eine vergleichende –anatomische und physiologische- Untersuchung an der Netzhaut von Atheriniformes (Hornhechte, fliegende Fische, Halbschnäbler, Ährenfische, Zwischenkärpflinge, u. a.) dar. Ziel dieser Studie ist es, unter Berücksichtigung der verwandtschaftlichen Verhältnisse zu klären, inwieweit sich in Morphologie und spektraler Empfindlichkeit der äußeren Retina Anpassungen an die visuelle Umwelt zeigen. 13 Arten aus 8 Familien wurden licht- u...

  5. Stable isotope evidence for trophic overlap of sympatric Mexican Lake Chapala silversides (Teleostei: Atherinopsidae: Chirostoma spp.

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    Norman Mercado-Silva

    2015-06-01

    Full Text Available We explore the trophic role that a diverse sympatric group of fishes in the genus Chirostoma play in a large, shallow lake in central Mexico, Lake Chapala. We use δ13C and δ15N stable isotope - based food web analyses to explore how they relate to other components of the Lake Chapala ecosystem. We find five Chirostoma species in top trophic levels of the Chapala food web compared to other fishes, relying on a combination of zooplankton, fish and benthic resources as energy sources. Food web metric analyses showed generally overlapping trophic niches for members of Chirostoma, especially in terms of δ13C. However, C. jordani had lower mean δ15N isotopic values than C. promelas. As a group, "pescados blancos" (C. sphyraena and C. promelas also had higher δ15N signatures than "charales" (C. consocium, C. jordani and C. labarcae reflecting greater piscivory, but these differences were not strong for all food web metrics used. Trophic overlap among species of Chirostoma in Lake Chapala raises questions about the forces that might have led to a morphologically diverse but functionally similar and monophyletic group of species.

  6. Multi-locus fossil-calibrated phylogeny of Atheriniformes (Teleostei, Ovalentaria).

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    Campanella, Daniela; Hughes, Lily C; Unmack, Peter J; Bloom, Devin D; Piller, Kyle R; Ortí, Guillermo

    2015-05-01

    Phylogenetic relationships among families within the order Atheriniformes have been difficult to resolve on the basis of morphological evidence. Molecular studies so far have been fragmentary and based on a small number taxa and loci. In this study, we provide a new phylogenetic hypothesis based on sequence data collected for eight molecular markers for a representative sample of 103 atheriniform species, covering 2/3 of the genera in this order. The phylogeny is calibrated with six carefully chosen fossil taxa to provide an explicit timeframe for the diversification of this group. Our results support the subdivision of Atheriniformes into two suborders (Atherinopsoidei and Atherinoidei), the nesting of Notocheirinae within Atherinopsidae, and the monophyly of tribe Menidiini, among others. We propose taxonomic changes for Atherinopsoidei, but a few weakly supported nodes in our phylogeny suggests that further study is necessary to support a revised taxonomy of Atherinoidei. The time-calibrated phylogeny was used to infer ancestral habitat reconstructions to explain the current distribution of marine and freshwater taxa. Based on these results, the current distribution of Atheriniformes is likely due to widespread marine dispersal along the margins of continents, infrequent trans-oceanic dispersal, and repeated invasion of freshwater habitats. This conclusion is supported by post-Gondwanan divergence times among families within the order, and a high probability of a marine ancestral habitat. PMID:25769409

  7. The complete mitochondrial genome of the Parkinson's Rainbowfish, Melanotaenia parkinsoni (Atheriniformes: Melanotaeniidae).

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    Wang, Lei; Chen, Zaizhong; Gao, Jianzhong; Chen, Xiaowu; Li, Zhongpu; Yu, Yongliang; Zhao, Yuming

    2016-07-01

    In this study, the complete mitogenome sequence of the Parkinson's Rainbowfish, Melanotaenia parkinsoni (Atheriniformes: Melanotaeniidae) has been sequenced by next-generation sequencing method. The assembled mitogenome is 16 529 bp in length including 13 protein-coding genes, 22 transfer RNAs and 2 ribosomal RNAs genes. The overall base composition of Parkinson's Rainbowfish is 28.1% A, 29.7% C, 15.7% G, 26.5% T and shows 93% identity with Lake Kutubu Rainbowfish, M. lacustris. The complete mitogenome of the Parkinson's Rainbowfish provides essential and important DNA molecular data for further phylogeography and evolutionary analysis for Rainbowfish phylogeny. PMID:27158786

  8. Comparación del efecto anestésico del aceite de clavo, solución salina y solución coloidal en juveniles de Chirostoma jordani (Woolman, 1894) Comparison of anaesthetic effect of clove oil, saline solution and colloidal solution in juvenile Chirostoma jordani (Woolman, 1894)

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    G. Vázquez; Castro, T.; Hernández, A.; Castro, J.; Lara, R.

    2013-01-01

    Los peces de la especie Chirostoma jordani presentan un intenso estrés durante las prácticas de manejo, dejándolos susceptibles a enfermedades y a tasas altas de mortalidad. El objetivo del presente estudio fue comparar el efecto anestésico del aceite de clavo, solución salina y una solución coloidal (Pentabiocare) en juveniles de Chirostoma jordani. Para cada tratamiento se utilizaron 18 ejemplares de C. jordani de dos meses de edad. Los tratamientos constaron en aceite de clavo (5, 8, 13 y ...

  9. Comparación del efecto anestésico del aceite de clavo, solución salina y solución coloidal en juveniles de Chirostoma jordani (Woolman, 1894)

    OpenAIRE

    G. Vázquez; Castro, T.; Hernández, A.; Castro, J.; Lara, R.

    2013-01-01

    Los peces de la especie Chirostoma jordani presentan un intenso estrés durante las prácticas de manejo, dejándolos susceptibles a enfermedades y a tasas altas de mortalidad. El objetivo del presente estudio fue comparar el efecto anestésico del aceite de clavo, solución salina y una solución coloidal (Pentabiocare) en juveniles de Chirostoma jordani. Para cada tratamiento se utilizaron 18 ejemplares de C. jordani de dos meses de edad. Los tratamientos constaron en aceite de clavo (5, 8, 13 y ...

  10. Spatial patterns of zooplanktivore Chirostoma species (Atherinopsidae during water-level fluctuation in the shallow tropical Lake Chapala, Mexico: seasonal and interannual analysis

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    Rodrigo Moncayo-Estrada

    2011-01-01

    Full Text Available This study addresses the influence of water-level fluctuations on fish distribution at two temporal scales: seasonal (dry and rainy and interannual (low and high volume conditions. The analysis of abundance relationships among three zooplanktivore Chirostoma species at fifteen sites in Lake Chapala, Mexico, revealed the significant influence of contrasting conditions (P=0.0002. Seasonally, segregation was more related to species dominance in the dry season and exclusively related to environmental characteristics in the rainy season. Interanually, biotic influence occurred in the shallowest and the deepest episodes of the lake. Environmental characteristics influenced species distribution when the lake reached 25% of its volume. Site, depth, temperature, and salinity were the leading factors influencing fish distribution. These results emphasize the necessity to implement different management strategies according to lake volume, particularly when a critical threshold is reached.El presente estudio describe la influencia que tiene la fluctuación del nivel del agua en la distribución de los peces a dos diferentes escalas: estacional (estiaje y lluvias e interanual (condiciones de bajo y alto volumen. El análisis de las relaciones de abundancia entre tres especies zooplanctófagas de Chirostoma en quince sitios del Lago de Chapala, México, reveló una influencia estadísticamente significativa en las condiciones contrastantes (P=0.0002. Estacionalmente, la segregación estuvo más relacionada a la dominancia de las especies en la época de estiaje y exclusivamente relacionada a las características ambientales en la época de lluvias. Interanualmente, la influencia biótica se presenta en los episodios más someros y más profundos del lago. Las características ambientales influenciaron la distribución de las especies cuando el lago alcanzó el 25% de su volumen. El sitio geográfico, profundidad, temperatura y salinidad fueron los principales

  11. Diversification of substrate specificities in teleostei Fads2: characterization of Δ4 and Δ6Δ5 desaturases of Chirostoma estor.

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    Fonseca-Madrigal, Jorge; Navarro, Juan C; Hontoria, Francisco; Tocher, Douglas R; Martínez-Palacios, Carlos A; Monroig, Óscar

    2014-07-01

    Currently existing data show that the capability for long-chain PUFA (LC-PUFA) biosynthesis in teleost fish is more diverse than in other vertebrates. Such diversity has been primarily linked to the subfunctionalization that teleostei fatty acyl desaturase (Fads)2 desaturases have undergone during evolution. We previously showed that Chirostoma estor, one of the few representatives of freshwater atherinopsids, had the ability for LC-PUFA biosynthesis from C18 PUFA precursors, in agreement with this species having unusually high contents of DHA. The particular ancestry and pattern of LC-PUFA biosynthesis activity of C. estor make this species an excellent model for study to gain further insight into LC-PUFA biosynthetic abilities among teleosts. The present study aimed to characterize cDNA sequences encoding fatty acyl elongases and desaturases, key genes involved in the LC-PUFA biosynthesis. Results show that C. estor expresses an elongase of very long-chain FA (Elovl)5 elongase and two Fads2 desaturases displaying Δ4 and Δ6/Δ5 specificities, thus allowing us to conclude that these three genes cover all the enzymatic abilities required for LC-PUFA biosynthesis from C18 PUFA. In addition, the specificities of the C. estor Fads2 enabled us to propose potential evolutionary patterns and mechanisms for subfunctionalization of Fads2 among fish lineages. PMID:24792929

  12. Comparación del efecto anestésico del aceite de clavo, solución salina y solución coloidal en juveniles de Chirostoma jordani (Woolman, 1894 Comparison of anaesthetic effect of clove oil, saline solution and colloidal solution in juvenile Chirostoma jordani (Woolman, 1894

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    G Vázquez

    2013-01-01

    Full Text Available Los peces de la especie Chirostoma jordani presentan un intenso estrés durante las prácticas de manejo, dejándolos susceptibles a enfermedades y a tasas altas de mortalidad. El objetivo del presente estudio fue comparar el efecto anestésico del aceite de clavo, solución salina y una solución coloidal (Pentabiocare en juveniles de Chirostoma jordani. Para cada tratamiento se utilizaron 18 ejemplares de C. jordani de dos meses de edad. Los tratamientos constaron en aceite de clavo (5, 8, 13 y 25 µL/L, solución salina (7 g/L y solución coloidal (5 mL/L. Durante seis horas se registraron, en los peces, las fases de inducción a la anestesia y los tiempos de recuperación. Las concentraciones altas y los tiempos prolongados de exposición al aceite de clavo se asociaron a las fases profundas de la anestesia. La concentración de 25 µL/L de aceite de clavo indujo a los organismos a la fase tres y a partir de la tercer hora de exposición éstos entraron en la fase cinco, mientras que las soluciones salina y coloidal indujeron a los peces a la fase uno de sedación mostrando los lapsos más prolongados (seis horas. El tiempo de recuperación de los juveniles en la concentración de 25 µL/L de aceite de clavo se extendió a 3.006,0 ± 5,3 segundos, mientras que con solución salina y coloidal, la respuesta de los peces a la recuperación del ritmo opercular, reactividad a estímulos externos y natación activa fue entre 60 a 180 segundos. Los resultados de este experimento indicaron que la solución salina y solución coloidal mantuvieron a los juveniles de C. jordani en una sedación ligera durante un lapso de seis horas con tiempos breves de recuperación. El uso de aceite de clavo en dosis de 5 y 13 µL/L indujo a los juveniles a estados de anestesia ligera y profunda respectivamente, con una recuperación de no más de 420 segundos.The fish Chirostoma jordani undergoes intense stress during handling practices, making it susceptible to

  13. Growth hormone-insuline-like growth factor-I system in pejerrey Odontesthes bonariensis (Atheriniformes

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    S.E. Arranz

    2008-07-01

    Full Text Available Using biotechnology to increase the growth rates of fish is likely to reduce production costs per unit of food. Among vertebrates, fish appear to occupy a unique position, when growth patterns are considered. With few exceptions, fish species tend to grow indeterminately, implying that size is never fixed. Both hyperplasia and hypertrophy contribute to post-larval muscle growth in fish. Growth hormone (GH - Insulin-like Growth Factor I (IGF-I is the most important growth axis in fish. Our experimental model, the pejerrey, Odontesthes bonariensis (Ateriniformes is a South American inland water fish considered to be a promising species for intensive aquaculture. However, one major drawback to achieve this goal is its slow growth in captivity. In order to understand how growth is regulated in this species, our first objective was to characterized pejerrey GH- IGF-I axis. We first cloned and characterized pejerrey (pj GH, IGF-I and the growth hormone receptors (GHRs I and II. In addition to providing valuable data for evolutionary comparison of GH, investigation of GH action in teleosts is particularly important because of its potential application in aquaculture. GH can not only promote the somatic growth in fish but also lower dietary protein requirements. A prerequisite for providing sufficient amounts of GH for basic research and aquaculture application is a large-scale production of GH. For that purpose, recombinant pjGH was expressed in a bacterial system. Protocols for solubilization and proper folding were achieved. Activity of recombinant pjGH was assessed in fish by measuring the liver IGF-I response to different doses of GH. IGF-I transcript was measured in the liver after pjGHr in vivo stimulation by means of quantitative real-time PCR assays. A dose-dependent response of IGF-I mRNA was observed after pjGHr administration, and reached a 6 fold IGF-I maximum increase over control group when 2.5 µg pjGH /g-body weight were injected. Temporal analysis of hepatic IGF-I mRNA levels showed that administration of a single dose of pjGHr into juvenile pejerrey resulted in a significant increase (P<0.02 9 hours post injection. These results demonstrates that recombinant pjGH could promote a dramatic response in liver, increasing the IGF-I mRNA level. We also study the effect of GH on muscle growth after oral administration. A significant association between GH doses and mean fiber area (MFA was observed even with a caloric restrictive diet. MFA increased 3.7 µm² per each unit of GH supplied indicating that GH promoted white muscle hypertrophy. These preliminary data indicates that GH could be absorbed by the intestine in an active form and promote somatic growth.

  14. Ultrastructure of fresh and post thawed sperm of pejerrey Odontesthes bonariensis (Atheriniformes

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    Ángela Gárriz

    2013-01-01

    Full Text Available In the present study it was showed for the first time the ultrastructural morphology of O. bonariensis sperm using electron microscopy techniques. Different kinds of abnormalities were described in fresh and post thawed sperm caused by crogenic protocols. Pejerrey spermatozoon is uniflagellated and is differentiated into three parts: a small roundish head (~1.80µm in length and 1.67µm in width, a midpiece or transitional region (~1.11µm in length and 1.56µm in width, and a long tail or flagellum (~29.08µm. Samples of fresh and post thawed sperm showed evidence of morphological anomalies affecting various intracellular compartments. Spermatozoa with swollen, ruptured, or absent membranes in the head showing excess of cytoplasm, and with alteration of the spatial orientation of the mitochondria were observed. A swollen flagellum was observed containing cytoplasmic vesicles, distributed along the whole length or concentrated in a restricted part of the tail. It was also found a high level of abnormalities (60% in frozen sperm when compared with normal sperm (18% reflecting the damage provoked by cryopreservation procedures.

  15. Assessment of condition in pejerrey Odontesthes bonariensis (Atheriniformes: Atherinopsidae populations: which index works best?

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    Claudio R. M. Baigún

    2009-09-01

    Full Text Available The pejerrey Odontesthes bonariensis is the most important target species in temperate freshwater fisheries of Argentina, and assessment of condition has been a regular practice and common diagnostic tool. Most pejerrey fishery studies have used Fulton's (K index, without testing whether underlying assumptions or requirements were met. We analyzed and contrasted the applicability of K, Kn and Wr indices to assess condition status in several pejerrey populations inhabiting Pampean lakes. Our results showed that whereas Wr and Kn displayed significant condition changes across length at some study lakes, Kn portrayed a small range of variation. We also noted that pejerrey maximum length and size structure strongly varied among populations probably due to the characteristics of trophic niche changes through lifespan, depending on lake limnological characteristics and zooplankton availability. We conclude that the K index should be disregarded in those cases where populations show allometric growth and size ranges strongly vary. In turn, the Kn index appears to be only appropriate for regular within population assessment, being difficult to apply when comparisons between populations are needed and when they exhibit different weight-length relationship slopes. Finally, the Wr index should be strongly preferred if the objective is to perform comparisons between pejerrey populations, particularly when population structure is not well known, stocking has been used for population recovery, lakes are strongly supported by limnological changes, data are limited to only one or few samplings and metaphoetesis is suspected in pejerrey populations.O peixe-rei Odontesthes bonariensis é a espécie mais importante na pesca de água doce da região temperada da Argentina, e a avaliação de sua condição corpórea tem sido uma prática normal e uma ferramenta de diagnóstico bastante utilizada. Grande parte dos estudos sobre a pesca do peixe-rei utiliza o índice de Fulton (K, sem testar se seus pressupostos são atendidos. Nós analisamos e comparamos a aplicabilidade dos índices K, Kn e Wr para a avaliação do fator de condição em várias populações de peixe-rei em lagos dos Pampas. Nossos resultados mostram que, enquanto o Wr e o Kn dependeram significativamente do comprimento corporal em alguns lagos, o Kn apresentou uma pequena amplitude de variação. Foi também notado que o comprimento máximo e a estrutura de tamanho variaram fortemente entre populações, provavelmente devido às mudanças ontogenéticas no nicho trófico, dependendo das características limnológicas e da disponibilidade de zooplâncton. Concluímos que o índice K deve ser desconsiderado nos casos em que as populações apresentam variações alométricas marcantes no crescimento e na amplitude de tamanhos. O índice Kn parece ser apropriado apenas para avaliações de uma única população, não sendo apropriado para comparações entre populações quando elas exibem diferentes inclinações na relação peso-comprimento. Finalmente, o índice Wr é recomendado se o objetivo for fazer comparações entre populações de peixe-rei, particularmente quando a estrutura populacional não é bem conhecida, a estocagem tenha sido usada para a recuperação populacional, os lagos apresentam grandes variações limnológicas, os dados se limitam a uma ou poucas amostras e suspeita-se da ocorrência de mudanças ontogenéticas na dieta.

  16. Modelos nulos en interacciones biológicas, una propuesta: depredación en chirostoma riojai-zooplancton

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    Octavio M. Vilchis

    2000-01-01

    Full Text Available Se muestra una propuesta de construcción rápida y confiable de los modelos, a partir de una prueba de bondad de ajuste y una de "G" con el fin de apreciar diferencias significativas. Se analiza un estudio de caso que presenta un patrón ecológico (depredación conocido, entre un pez y sus presas.

  17. Populations of Odontesthes (Teleostei: Atheriniformes) in the Andean region of Southern South America: body shape and hybrid individuals

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    Cecilia Conte-Grand; Julie Sommer; Guillermo Ortí; Víctor Cussac

    2015-01-01

    The original distribution area of the Patagonian 'pejerrey' Odontesthes hatcheri has been subjected to the introduction of a related species; the Bonaerensean 'pejerrey' Odontesthes bonariensis. This species currently coexists with O. hatcheri in lakes and reservoirs, and can interbreed and produce fertile hybrid offspring. The purposes of this study were; a) the extensive sampling of Patagonian and Andean-Cuyan populations of pejerrey, b) the species identification according to taxonomic key...

  18. Populations of Odontesthes (Teleostei: Atheriniformes in the Andean region of Southern South America: body shape and hybrid individuals

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    Cecilia Conte-Grand

    2015-03-01

    Full Text Available The original distribution area of the Patagonian 'pejerrey' Odontesthes hatcheri has been subjected to the introduction of a related species; the Bonaerensean 'pejerrey' Odontesthes bonariensis. This species currently coexists with O. hatcheri in lakes and reservoirs, and can interbreed and produce fertile hybrid offspring. The purposes of this study were; a the extensive sampling of Patagonian and Andean-Cuyan populations of pejerrey, b the species identification according to taxonomic key, c validation of taxonomic results on the basis of mitochondrial DNA composition, and d applying morphometric analysis to explore the effects of hybridization and environmental conditions on body shape. Cytochrome b sequence analysis showed a high degree of genetic divergence between species and low intraspecific variation in O. hatcheri. Geometric Morphometric Analyses detected shape differences in agreement with diagnostic characteristics of each species. Putative hybrids exhibiting intermediate diagnostic characteristics were identified by Geometric Morphometric Analysis. Significant regressions between body shape and total phosphorus and altitude were found, suggesting a dependence on trophic web structure. This multi-level approach suggests the introgression of O. bonariensis into several O. hatcheri populations throughout Patagonia. Managers should take this into account when considering further exotic introductions into regions where non-native fishes have not yet become established.

  19. Importancia de los lípidos en la reproducción y ontogenia del pez blanco de Pátzcuaro (Chirostoma estor estor)

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    Aparicio, B.

    2004-01-01

    Para producir larvas de peces con buenos rendimientos, se deben conocer los requerimientos nutricionales de la especie, particularmente en los primeros estadios larvarios. Además, se sabe que la nutrición de los reproductores influye directamente en la calidad de las larvas debido, principalmente, a la cantidad y calidad de lípidos que son transferidos desde la gónada hacia los huevos. El objetivo de este trabajo fue analizar la composición de lípidos en huevos, embriones y larvas de pez blan...

  20. Population genetic structure of the striped silverside, Atherinomorus endrachtensis (Atherinidae, Atheriniformes, Teleostei), inhabiting marine lakes and adjacent lagoons in Palau: marine lakes are "Islands" for marine species.

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    Gotoh, Ryo O; Chiba, Satoru N; Goto, Tadasuke V; Tamate, Hidetoshi B; Hanzawa, Naoto

    2011-01-01

    Although evidence for the evolution of terrestrial species on islands continues to rapidly accumulate, little is known about the evolution of marine species in geographically isolated environments such as islands as ocean currents often facilitate gene flow among populations. In this study, we focused on marine lakes of the Palau Islands, which are considered to be true analogues of terrestrial islands for marine species. To examine evolutionary processes in marine lakes, we conducted population genetic analyses on marine lake and lagoon populations of the striped silverside, Atherinomorus endrachtensis, using two mitochondrial DNA markers differing in evolutionary rate, the cytochrome b gene and the control region. The analyses revealed that the amount of genetic diversity of marine lake populations is much lower than that of lagoon populations and high levels of genetic differentiation occur among marine lake and lagoon populations. The present study has shown that marine lake populations have been completely isolated and have differentiated from lagoon populations, and each marine lake population is experiencing different evolutionary processes. These findings clearly demonstrate that marine lakes are excellent environments for the evolutionary study of marine species. PMID:22362031

  1. Seasonal variation of parasitism in pejerrey Odontesthes bonariensis (Atheriniformes, Atherinopsidae from La Viña reservoir (Córdoba, Argentina Variação sazonal do parasitismo em Peixe-rei Odontesthes bonariensis (Atheriniformes, Atherinopsidae no reservatório La Viña, Córdoba, Argentina

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    Miguel Mancini

    2008-03-01

    Full Text Available The pejerrey Odontesthes bonariensis is the most important freshwater fish of Argentina central region. The present study was conducted to describe the seasonal variation of parasitism in O. bonariensis from La Viña reservoir (31º 17'S, 65º 01'W, located in the province of Córdoba, Argentina. Between years 1999 and 2002, 573 fishes were caught, and their parasite infection and relative weight (Wr were assesed. Three parasites were found, Lernaea cyprinacea (Crustacea, Contracaecum spp. larvae (Nematoda and Cangatiella macdonaghi (Cestoda. Overall, Contracaecum spp. prevalence and intensity were very low. Lernaea cyprinacea and Cangatiella macdonaghi prevalences increased during summer and spring (P O peixe rei Odontesthes bonariensis é um peixe de água doce de grande importância na região central da Argentina. O objetivo deste trabalho foi descrever a sazonalidade do parasitismo de O. bonariensis no reservatrio La Viña (31º 17'S, 65º 01'W, província de Córdoba, Argentina. Durante os anos 1999 e 2002 foram capturados 573 peixes. Nestes se fez à avaliação da condição corporal usando como parâmetro o peso relativo e identificaram-se os seguintes parasitos: Lernaea cyprinacea (Crustacea, Contracaecum spp. (Nematoda e Cangatiella macdonaghi (Cestoda. As prevalências e intensidades de Contracaecum spp. foram muito baixas. Houve diferenças nas prevalências de L. cyprinacea e C. macdonaghi na época do ano (P < 0,01, sendo maiores no verão e na primavera, respectivamente. Houve diferenças estacionais na intensidade de L. cyprinacea (P < 0,05 e na densidade de C. macdonaghi (P < 0,01, neste ultimo alcançou-se um valor máximo nas amostras de 32,0 (±22,5 parasitos por cm³ de conteúdo digestivo. Não houve associação entre o parasitismo e o peso relativo dos peixes. Embora haja certa sazonalidade, as diferentes cargas parasitárias encontradas nâo prejudicam a saúde de O. bonariensis enquanto sua condição corporal.

  2. Estrutura da população e aspectos reprodutivos do peixe-rei Atherinella brasiliensis (Quoy & Gaimard) (Atheriniformes, Atherinopsidae) em áreas rasas do complexo estuarino de Paranaguá, Paraná, Brasil Structure of the population and reproductive aspects of silverside Atherinella brasiliensis (Quoy & Gaimard) (Atheriniformes, Atherinopsidae) in shallow areas of the estuarine complex Paranaguá, Paraná, Brazil

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    Luís F. Fávaro; Elton C. de Oliveira; Nelsy F. Verani

    2007-01-01

    A estrutura populacional e aspectos reprodutivos de Atherinella brasiliensis (Quoy & Gaimard, 1825) foram analisados mensalmente de maio de 2000 a abril de 2001, em oito pontos de ambientes rasos do eixo norte-sul do complexo estuarino de Paranaguá. As análises ambientais das variáveis pH, oxigênio dissolvido, transparência e salinidade da água sugerem a existência de um gradiente ambiental crescente no sentido norte-sul do estuário. A temperatura da água evidenciou a variação temporal no sis...

  3. Estrutura da população e aspectos reprodutivos do peixe-rei Atherinella brasiliensis (Quoy & Gaimard (Atheriniformes, Atherinopsidae em áreas rasas do complexo estuarino de Paranaguá, Paraná, Brasil Structure of the population and reproductive aspects of silverside Atherinella brasiliensis (Quoy & Gaimard (Atheriniformes, Atherinopsidae in shallow areas of the estuarine complex Paranaguá, Paraná, Brazil

    Directory of Open Access Journals (Sweden)

    Luís F. Fávaro

    2007-12-01

    Full Text Available A estrutura populacional e aspectos reprodutivos de Atherinella brasiliensis (Quoy & Gaimard, 1825 foram analisados mensalmente de maio de 2000 a abril de 2001, em oito pontos de ambientes rasos do eixo norte-sul do complexo estuarino de Paranaguá. As análises ambientais das variáveis pH, oxigênio dissolvido, transparência e salinidade da água sugerem a existência de um gradiente ambiental crescente no sentido norte-sul do estuário. A temperatura da água evidenciou a variação temporal no sistema estudado, mostrando-se intimamente relacionado com o processo reprodutivo. O pico de atividade reprodutiva foi determinado para fêmeas e machos, respectivamente, nos meses de outubro e setembro, período em que se verificou a proporção de duas fêmeas para um macho. O predomínio de indivíduos jovens no estuário ocorreu no final da primavera e durante o verão, após o período reprodutivo. As análises sazonais de comprimento e de massa corporal sugerem a existência de um padrão cíclico de crescimento ao longo do ano, o qual reflete o período reprodutivo e o recrutamento. Assim, conclui-se que A. brasiliensis é uma espécie estuarina residente, mostrando-se amplamente distribuída nas áreas rasas estuarinas, podendo ser considerada chave em avaliações de impacto ambiental e/ou em ações de planos de manejo e conservação em ambientes estuarinos.The population structure and reproductive aspects of Atherinella brasiliensis (Quoy & Gaimard, 1825 had been analyzed monthly from May 2000 to April 2001 in eight points of shallow areas of the estuarine complex Paranaguá. The environment analyzes of the parameters pH, dissolved oxygen, transparency and salinity of the water suggest the existence of an increasing environment gradient in the direction North-South highway of the estuary. The temperature of the water evidenced the seasonal variation in the studied system, revealing related with the reproductive process. The peak of reproductive activity was determined for females and male, respectively, in the months of October and September, period where if it verified the ratio of two females for a male. The predominance of young individuals in the estuary occurred in the end of the spring and during the summer, after the reproductive period. The seasonal analyses of length and mass suggest the existence of a cyclical standard of growth to the long of the year, which reflects the reproductive period and the entrance of young individuals in the environment. Thus, it is concluded that A. brasiliensis is a resident estuarine species, revealing widely distributed in the estuarine shallow areas, being able to be considered key in evaluations of environmental impact and/or action of handling plans and conservation in estuarine environments.

  4. Spinitectus osorioi (Nematoda: Cystidicolidae) in the Mexican endemic fish Atherinella alvarezi (Atherinopsidae) from the Atlantic River drainage system in Chiapas, Southern Mexico

    OpenAIRE

    František Moravec; Guillermo Salgado-Maldonado; Juan M Caspeta-Mandujano

    2010-01-01

    Specimens of Spinitectus osorioi Choudhury and Pérez-Ponce de León, an intestinal nematode species previously considered to be specific to Chirostoma spp and endemic to some lakes in the Pacific drainage in Michoacán, were collected from the freshwater fish Atherinella alvarezi (Díaz-Pardo) (Atherinopsidae) of the Michol River near Palenque, Chiapas, Southern Mexico, which belongs to the Atlantic drainage system. Studies using light and scanning electron microscopy revealed some taxonomically...

  5. Trophic interactions among sympatric zooplanktivorous fish species in volume change conditions in a large, shallow, tropical lake

    OpenAIRE

    Rodrigo Moncayo-Estrada; Owen T. Lind; Carlos Escalera-Gallardo

    2011-01-01

    Significant reductions in the water volume of shallow lakes impose a restriction on species segregation promoting more interactions in the trophic relationships. The diets of three closely related zooplanktivorous silversides belonging to the Atherinopsidae species flock of lake Chapala , Mexico, were analyzed at two sites (Chirostoma jordani, C. labarcae, and C. consocium). Diets were described in critical shallow (August 2000) and volume recovery conditions (August 2005). Diets included mai...

  6. The complete mitochondrial genome of red rainbowfish (Glossolepis incises Weber 1907).

    Science.gov (United States)

    Zhao, Yuming; Chen, Zaizhong; Gao, Jianzhong; Wang, Lei; Li, Zhongpu; Yu, Yongliang; Zhou, Qi

    2016-09-01

    In this study, the mitochondrial genome of Glossolepis incisus (Weber 1907 ) (Atheriniformes: Melanotaeniidae) was sequenced for the first time. The assembled mitogenome consisting of 16 529 bp, includes 13 protein-coding genes, 22 transfer RNAs, 2 ribosomal RNAs genes and 1 putative control region. The overall base composition of G. incisus is 27.51% for A, 30.04% for C, 16.06% for G, 26.39% for T and showS 91% identities to Lake Kutubu Rainbowfish, Melanotaenia lacustris. These data will provide useful molecular information for phylogenetic relationships within the family Melanotaeniidae species. PMID:26359678

  7. Espectro trófico del bagre Ictalurus punctatus (Silurifomes: Ictaluridae), en la presa Lázaro Cárdenas, Indé, Durango, México Trophic spectrum of the catfish Ictalurus punctatus (Siluriformes: Ictaluridae), in the Lázaro Cárdenas reservoir, Indé, Durango, Mexico

    OpenAIRE

    Gabriel Fernando Cardoza Martínez; José Luis Estrada Rodríguez; Fernando Alonzo Rojo; Carmen Leticia Mar Tovar; Frances Gelwick

    2011-01-01

    Se analizó el contenido de 240 estómagos de Ictalurus punctatus (Rafinesque, 1818), colectados de 2006 a 2007, con el objetivo de determinar su espectro trófico, su variación por talla y época climática. Los contenidos estomacales se analizaron en laboratorio y los organismos se determinaron hasta nivel de orden. Los datos obtenidos fueron analizados por métodos cuantitativos y cualitativos. Los órdenes más frecuentes fueron Perciformes y Atheriniformes que corresponden a peces forraje, así c...

  8. Espectro trófico del bagre Ictalurus punctatus (Silurifomes: Ictaluridae, en la presa Lázaro Cárdenas, Indé, Durango, México Trophic spectrum of the catfish Ictalurus punctatus (Siluriformes: Ictaluridae, in the Lázaro Cárdenas reservoir, Indé, Durango, Mexico

    Directory of Open Access Journals (Sweden)

    Gabriel Fernando Cardoza Martínez

    2011-08-01

    Full Text Available Se analizó el contenido de 240 estómagos de Ictalurus punctatus (Rafinesque, 1818, colectados de 2006 a 2007, con el objetivo de determinar su espectro trófico, su variación por talla y época climática. Los contenidos estomacales se analizaron en laboratorio y los organismos se determinaron hasta nivel de orden. Los datos obtenidos fueron analizados por métodos cuantitativos y cualitativos. Los órdenes más frecuentes fueron Perciformes y Atheriniformes que corresponden a peces forraje, así como algas verdes del orden Charales. Además, se encontraron otros siete órdenes de invertebrados: Schizodonta, Odonata, Himenoptera, Orthoptera, Hemiptera, Homoptera y Scorpionida, además de dos órdenes de plantas: Poales y Fabales. El orden Perciforme constituyó casi la mitad del total del peso del contenido estomacal, seguido por los órdenes Atheriniforme y Charales. En las estaciones de verano e invierno se presentó el mayor número de estómagos vacíos, mientras que en primavera se encontró el mayor número de estómagos llenos. La cantidad de alimento ingerida en la estación de invierno fue significativamente menor que en las demás estaciones. El principal alimento en primavera, verano y otoño, fueron los peces, mientras que en invierno hubo mayor preferencia por las algas.Having the objective of determining their trophic spectrum and their variations within a year, the contents of 240 stomachs of Ictalurus punctatus (Rafinesque, 1818 were analyzed from 2006 to 2007. The items of the stomach contents were determined to the order level. The data was analyzed by different quantitative and qualitative methods. The most frequent orders were Perciforms and Atheriniforms corresponding to forage fish, along with green algae of the Charales order. Also, seven orders of invertebrates were found: Schizodonta, Odonata, Himenoptera, Orthoptera, Hemiptera, Homoptera and Scorpionida, and two orders of plants: Poales and Fabales. The Perciform

  9. Sm-Nd and Rb-Sr Ages for MIL 05035: Implications for Surface and Mantle Sources

    Science.gov (United States)

    Nyquist, L. E.; Shih, C-Y.; Reese, Y. D.

    2007-01-01

    The Sm-Nd and Rb-Sr ages and also the initial Nd and Sr isotopic compositions of MIL 05035 are the same as those of A-881757. Comparing the radiometric ages of these meteorites to lunar surface ages as modeled from crater size-frequency distributions as well as the TiO2 abundances and initial Sr-isotopic compositions of other basalts places their likely place of origin as within the Australe or Humboldtianum basins. If so, a fundamental west-east lunar asymmetry in compositional and isotopic parameters that likely is due to the PKT is implied.

  10. Complexities in pyroxene compositions derived from absorption band centers: Examples from Apollo samples, HED meteorites, synthetic pure pyroxenes, and remote sensing data

    Science.gov (United States)

    Moriarty, D. P.; Pieters, C. M.

    2016-02-01

    We reexamine the relationship between pyroxene composition and near-infrared absorption bands, integrating measurements of diverse natural and synthetic samples. We test an algorithm (PLC) involving a two-part linear continuum removal and parabolic fits to the 1 and 2 μm bands—a computationally simple approach which can easily be automated and applied to remote sensing data. Employing a suite of synthetic pure pyroxenes, the PLC technique is shown to derive similar band centers to the modified Gaussian model. PLC analyses are extended to natural pyroxene-bearing materials, including (1) bulk lunar basalts and pyroxene separates, (2) diverse lunar soils, and (3) HED meteorites. For natural pyroxenes, the relationship between composition and absorption band center differs from that of synthetic pyroxenes. These differences arise from complexities inherent in natural materials such as exsolution, zoning, mixing, and space weathering. For these reasons, band center measurements of natural pyroxene-bearing materials are compositionally nonunique and could represent three distinct scenarios (1) pyroxene with a narrow compositional range, (2) complexly zoned pyroxene grains, or (3) a mixture of multiple pyroxene (or nonpyroxene) components. Therefore, a universal quantitative relationship between band centers and pyroxene composition cannot be uniquely derived for natural pyroxene-bearing materials without additional geologic context. Nevertheless, useful relative relationships between composition and band center persist in most cases. These relationships are used to interpret M3 data from the Humboldtianum Basin. Four distinct compositional units are identified (1) Mare Humboldtianum basalts, (2) distinct outer basalts, (3) low-Ca pyroxene-bearing materials, and (4) feldspathic materials.

  11. Trophic interactions among sympatric zooplanktivorous fish species in volume change conditions in a large, shallow, tropical lake

    Directory of Open Access Journals (Sweden)

    Rodrigo Moncayo-Estrada

    2011-03-01

    Full Text Available Significant reductions in the water volume of shallow lakes impose a restriction on species segregation promoting more interactions in the trophic relationships. The diets of three closely related zooplanktivorous silversides belonging to the Atherinopsidae species flock of lake Chapala , Mexico, were analyzed at two sites (Chirostoma jordani, C. labarcae, and C. consocium. Diets were described in critical shallow (August 2000 and volume recovery conditions (August 2005. Diets included mainly cladocerans (Bosmina, Ceriodaphnia, and Daphnia and copepods (Cyclops. A significant difference in diets was detected when comparing years (MRPP analysis, A = 0.22, p La reducción significativa en el volumen de agua de los lagos someros impone una restricción en la segregación de las especies y promueve una mayor interacción en las relaciones tróficas. Se analizó la dieta de tres especies cercanamente emparentadas de zooplanctívoros pertenecientes al flock de Aterinópsidos del lago de Chapala en dos sitios (Chirostoma jordani, C. labarcae y C. consocium. Las dieta fue descrita en una condición somera crítica (Agosto 2000 y en una condición de recuperación del lago (Agosto 2005. En la dieta se incluyen principalmente cladóceros (Bosmina, Ceriodaphnia y Daphnia y copépodos (Cyclops. Se detectó una diferencia significativa en la dieta cuando se comparan los años (análisis MRPP, A = 0.22, p < 0.0001 y los sitios en los diferentes años (análisis MRPP, A = 0.17, p = 0.004. De acuerdo a los valores promedio de amplitud de nicho, las especies fueron clasificadas como especialistas y consumidores intermediarios. En condiciones someras, el pequeño intervalo de la amplitud de nicho (1.72 a 3.64 y los altos valores del traslape de nicho (D = 0.64, L = 8.62 indicaron un alto potencial para una interacción explotativa inter-específica. Cuando el lago se recupera en su volumen, un incremento en el intervalo de amplitud de nicho (1.04 a 4.96 y los

  12. Lunar Impact Basins: Stratigraphy, Sequence and Ages from Superposed Impact Crater Populations Measured from Lunar Orbiter Laser Altimeter (LOLA) Data

    Science.gov (United States)

    Fassett, C. I.; Head, J. W.; Kadish, S. J.; Mazarico, E.; Neumann, G. A.; Smith, D. E.; Zuber, M. T.

    2012-01-01

    Impact basin formation is a fundamental process in the evolution of the Moon and records the history of impactors in the early solar system. In order to assess the stratigraphy, sequence, and ages of impact basins and the impactor population as a function of time, we have used topography from the Lunar Orbiter Laser Altimeter (LOLA) on the Lunar Reconnaissance Orbiter (LRO) to measure the superposed impact crater size-frequency distributions for 30 lunar basins (D = 300 km). These data generally support the widely used Wilhelms sequence of lunar basins, although we find significantly higher densities of superposed craters on many lunar basins than derived by Wilhelms (50% higher densities). Our data also provide new insight into the timing of the transition between distinct crater populations characteristic of ancient and young lunar terrains. The transition from a lunar impact flux dominated by Population 1 to Population 2 occurred before the mid-Nectarian. This is before the end of the period of rapid cratering, and potentially before the end of the hypothesized Late Heavy Bombardment. LOLA-derived crater densities also suggest that many Pre-Nectarian basins, such as South Pole-Aitken, have been cratered to saturation equilibrium. Finally, both crater counts and stratigraphic observations based on LOLA data are applicable to specific basin stratigraphic problems of interest; for example, using these data, we suggest that Serenitatis is older than Nectaris, and Humboldtianum is younger than Crisium. Sample return missions to specific basins can anchor these measurements to a Pre-Imbrian absolute chronology.