Monorchiids (Digenea, Trematoda) of fishes in the Yucatán Peninsula, Mexico, with the description of three new species based on morphological and molecular data.

Adult specimens of monorchiids (Digenea) were collected from the intestines of the white grunt, Haemulon plumierii Lacepède (Haemulidae), and the white mullet, Mugil curema Valenciennes (Mugilidae) from five localities off the Yucatán Peninsula and one locality in the Gulf of Mexico. Some specimens were photographed and sequenced for two molecular markers, the large subunit (LSU) of nuclear rDNA and the cytochrome c oxidase subunit 1 (cox1) of mitochondrial DNA. Other specimens were processed for morphological analyses. Newly generated sequences were aligned with other sequences available in GenBank. Bayesian inference and maximum likelihood analyses were implemented using the data sets of LSU and cox1 independently. Reciprocal monophyly evidenced through phylogenetic analyses, sequence divergence values for both molecular markers, and detailed morphological analyses, including scanning electron microscopy photomicrographs, revealed three new genetic lineages, i.e., species, as parasites of M. curema. The three new species are Sinistroporomonorchis mexicanus n. sp., Sinistroporomonorchis yucatanensis n. sp., and Sinistroporomonorchis minutus n. sp. Two additional species of monorchiids were sampled, characterised molecularly, and re-described, namely Sinistroporomonorchis glebulentus (Overstreet, 1971) from the white mullet, and Alloinfundiburictus haemuli (Overstreet, 1969), from the white grunt.

Title: Monorchiidae (Digenea, Trematoda) de poissons de la péninsule du Yucatán, Mexique, avec description de trois nouvelles espèces sur la base de données morphologiques et moléculaires. Abstract: Des spécimens adultes de Monorchiidae (Digenea) ont été collectés dans les intestins de la gorette blanche, Haemulon plumierii Lacepède (Haemulidae), et du mulet blanc, Mugil curema Valenciennes (Mugilidae) de cinq localités au large de la péninsule du Yucatán et d'une localité dans le Golfe du Mexique. Certains spécimens ont été photographiés et séquencés pour deux marqueurs moléculaires, la grande sous-unité (LSU) de l'ADNr nucléaire et la sous-unité 1 de la cytochrome c oxydase (cox1) de l'ADN mitochondrial. D'autres spécimens ont été traités pour des analyses morphologiques. Les séquences nouvellement générées ont été alignées avec d'autres séquences disponibles dans GenBank. L'inférence bayésienne et les analyses de vraisemblance maximale ont été mises en œuvre en utilisant les ensembles de données de LSU et cox1 indépendamment. La monophylie réciproque mise en évidence par des analyses phylogénétiques, des valeurs de divergence de séquence pour les deux marqueurs moléculaires et des analyses morphologiques détaillées, y compris des photomicrographies au microscope électronique à balayage, a révélé trois nouvelles lignées génétiques, c'est-à-dire des espèces, qui sont parasites de M. curema. Les trois nouvelles espèces sont Sinistroporomonorchis mexicanus n. sp., Sinistroporomonorchis yucatanensis n. sp. et Sinistroporomonorchis minutus n. sp. (Monorchiidae). Deux espèces supplémentaires de Monorchiidae ont été échantillonnées, caractérisées moléculairement et redécrites, à savoir Sinistroporomonorchis glebulentus (Overstreet, 1971) du mulet blanc et Alloinfundiburictus haemuli (Overstreet, 1969) de la gorette blanche.

Bioaccumulation of mercury in Haemulopsis elongatus and Pomadasys macracanthus from the SE Gulf of California: condition indexes and health risk assessment.

Mercury (Hg) was measured in the muscle, liver, and gonads of Haemulopsis elongatus and Pomadasys macracanthus from Mazatlán (SE Gulf of California) to determine the relationships of the hepatosomatic index (HSI) and gonadosomatic index (GSI) of fish with Hg concentrations in the corresponding tissues. Health risk to consumers was assessed by using the hazard quotient (HQ), considering the average rate of fish consumption in Mexico and Hg concentration in the edible tissue. In H. elongatus, the highest Hg levels were measured in the liver (3.748 µg g-1); in P. macracanthus, the highest Hg concentration was quantified in the muscle (0.574 µg g-1). In P. macracanthus, the HSI was negatively correlated with Hg concentration in the liver; in H. elongatus, there was also a negative relationship between Hg levels in gonads and the GSI. Mean HQ values in Haemulopsis elongatus (0.005) and Pomadasys macracanthus (0.002) were below the value (HQ ≥ 1) of concern. The significant reduction of HSI and GSI with Hg increase in the liver and gonads may suggest that Hg bioaccumulation in these fish shows adverse physiological effects. Though HQ values in both species were below the unit, i.e., the consumption of the muscle from this species does not represent a health risk, it is necessary to carry out surveys of fish consumption rates in coastal areas of Mexico to do a more precise health risk assessment associated to Hg intake.

Geography of speciation affects rate of trait divergence in haemulid fishes.

Speciation and the interactions between recently diverged species are thought to be major causes of ecological and morphological divergence in evolutionary radiations. Here, we explore the extent to which geographical overlap and time since speciation may promote divergence in marine species, which represent a small fraction of currently published studies about the patterns and processes of speciation. A time-calibrated molecular phylogeny of New World haemulid fishes, a major radiation of reef and shore fishes in the tropical West Atlantic and East Pacific, reveals 21 sister species pairs, of which eight are fully sympatric and 13 are allopatric. Sister species comparisons show a non-significant relation between most of the phenotypic traits and time since divergence in allopatric taxa. Additionally, we find no difference between sympatric and allopatric pairs in the rate of divergence in colour pattern, overall body shape, or functional morphological traits associated with locomotion or feeding. However, sympatric pairs show a significant decrease in the rate of divergence in all of these traits with increasing time since their divergence, suggesting an elevated rate of divergence at the time of speciation, the effect of which attenuates as divergence time increases. Our results are consistent with an important role for geographical overlap driving phenotypic divergence early in the speciation process, but the lack of difference in rates between sympatric and allopatric pairs indicates that the interactions between closely related species are not dominant drivers of this divergence.

Morphological and molecular (28S rRNA) data of monogeneans (Platyhelminthes) infecting the gill lamellae of marine fishes in the Campeche Bank, southwest Gulf of Mexico.

During the examination of 913 fish specimens belonging to four families in the Campeche Bank (Gulf of Mexico), 23 gill ectoparasitic monogenean species were found, which belong to three families: Dactylogyridae, Microcotylidae and Diclidophoridae. The species Euryhaliotremaamydrum, E.carbuncularium, E.dunlapae, E.fajeravilae, E.fastigatum, E.longibaculum, E.paracanthi, E.tubocirrus, Haliotrematoidescornigerum, H.gracilihamus, H.heteracantha, H.longihamus, H.magnigastrohamus, H.striatohamus, Hamatopedunculariabagre, Neotetraonchusbravohollisae, and N.felis (all Dactylogyridae) were found on the hosts Lutjanussynagris, L.griseus, Ariopsisfelis, Bagremarinus, Archosargusrhomboidalis, and Haemulonplumieri. Additionally, Microcotylearchosargi, Microcotyle sp., and Microcotyloidesincisa (all Microcotylidae) were found on L.griseus and A.rhomboidalis; finally, Choricotyle sp. 1, Choricotyle sp. 2, and Choricotyle sp. 3 (all Diclidophoridae) were found on H.plumieri. The prevalence, abundance, mean intensity of infection, and supplementary taxonomic revisions for all monogeneans found are provided. Partial sequences of the 28S rRNA gene were also obtained for monogeneans of ariid, sparid, and haemulid host fishes to explore their systematic position within the Monogenea. New locality and host records for some previously described species of Euryhaliotrema, Hamatopeduncularia, Microcotyle, and Choricotyle from lutjanid, ariid, sparid, and haemulid hosts were reported. The present study adds evidence supporting the interoceanic occurrence of the same monogenean species (on lutjanids) on the west-east Atlantic and Pacific Oceans (= amphiamerican species). As previously suggested, there are at least, two possibilities to explain that parasite distribution: differentiation of morphological features in these monogeneans have resulted in only slight to insignificant morphological changes developing over the extended period of 3.2 mya (when the Isthmus of Panama was closing) and/or speciation is only evident at molecular level.

Biologia populacional do peixe-pedra, Genyatremus luteus (Bloch, 1790), na costa amazônica brasileira / Population biology of torroto grunt, Genyatremus luteus (Bloch, 1790), Brazilian amazonian coast

Genyatremus luteus é uma espécie de peixe de importância comercial no estado do Pará. Neste estudo foi investigada a biologia populacional de G. luteus em um estuário da Amazônia Oriental. Para tanto, realizaram-se coletas de exemplares da espécie no Furo Grande, no período de outubro de 2012 a outubro de 2013, mensalmente, com rede de emalhar tipo block-net. Em laboratório, os indivíduos foram aferidos os comprimentos total, padrão e da cabeça e a altura, além de ser registrado o peso úmido. Após incisão ventral e retirada das gônadas, macroscopicamente, definiu-se o estádio gonadal das fêmeas e dos machos. Foram capturados 460 indivíduos cujos tamanhos e pesos variaram entre 4,50 e 21,40 cm e 1,36 e 148,26 g. As frequências relativas das fêmeas e dos machos foram diferentes do esperado de 1:1 (x2: 8,90; p<0,01), diferindo significativamente por sexo e classe de tamanho (p<0,01). As médias de tamanho (CT) apresentaram diferenças significativas em relação ao sexo (F=22,71; p<0,01), mês (F=35,80; p<0,01), período sazonal (F=6,03; p<0,01), estádio gonadal (F=29,77; p<0,01) e estádio gonadal por período sazonal (F=2,37; p<0,05). O peso úmido não diferiu estatisticamente por estádio gonadal, período sazonal e sexo. O diagrama de ordenação demonstrou que a turbidez da água foi a variável que respondeu pela maior variabilidade dos dados (total de 97%). Os espécimes capturados neste estudo são pequenos em tamanho e peso e reprodutivamente imaturos, com maior ocorrência de fêmeas e em maior número no período seco.(AU)

Genyatremus luteus is specie of commercial importance in the Pará state. In this study, the population biology of G. luteus was investigated in an estuary of the Eastern Amazon, the collections occurred from October 2012 to October 2013, each month, in the tidal channel (Furo grande), with block net. In the laboratory the individuals were gauged the lengths: total, standard, head and height, in addition to weight being recorded. After ventral incision and gonads removal, the gonadal stage was defined for females and males macroscopically. 460 individuals were captured whose sizes and weights ranged from 4.50 to 21.40 cm and 1.36 and 148.26 g. The relative frequencies of females and males were different than expected from 1: 1 (x2: 8.90, p <0.01), differing significantly by sex and size class (p <0.01). The mean size (CT) presented differences significant in relation to sex (F = 22.71, p <0.01), month (F = 35.80, p <0.01) (P <0.01), gonadal stage (F = 29.77, p <0.01) and gonadal stage by seasonal period (F = 2.37, p <0.05). The wet weight did not differ statistically by gonadal stage, seasonal period and sex. The ordering diagram showed that the turbidity was the variable that responded by the greater variability in the data (total of 97%). The specimens captured in this study are small in size and weight and reproductively immature, with higher occurrence of females, in greater numbers in the dry period.(AU)

Biologia populacional do peixe-pedra, Genyatremus luteus (Bloch, 1790), na costa amazônica brasileira / Population biology of torroto grunt, Genyatremus luteus (Bloch, 1790), Brazilian amazonian coast

Genyatremus luteus é uma espécie de peixe de importância comercial no estado do Pará. Neste estudo foi investigada a biologia populacional de G. luteus em um estuário da Amazônia Oriental. Para tanto, realizaram-se coletas de exemplares da espécie no Furo Grande, no período de outubro de 2012 a outubro de 2013, mensalmente, com rede de emalhar tipo block-net. Em laboratório, os indivíduos foram aferidos os comprimentos total, padrão e da cabeça e a altura, além de ser registrado o peso úmido. Após incisão ventral e retirada das gônadas, macroscopicamente, definiu-se o estádio gonadal das fêmeas e dos machos. Foram capturados 460 indivíduos cujos tamanhos e pesos variaram entre 4,50 e 21,40 cm e 1,36 e 148,26 g. As frequências relativas das fêmeas e dos machos foram diferentes do esperado de 1:1 (x2: 8,90; p<0,01), diferindo significativamente por sexo e classe de tamanho (p<0,01). As médias de tamanho (CT) apresentaram diferenças significativas em relação ao sexo (F=22,71; p<0,01), mês (F=35,80; p<0,01), período sazonal (F=6,03; p<0,01), estádio gonadal (F=29,77; p<0,01) e estádio gonadal por período sazonal (F=2,37; p<0,05). O peso úmido não diferiu estatisticamente por estádio gonadal, período sazonal e sexo. O diagrama de ordenação demonstrou que a turbidez da água foi a variável que respondeu pela maior variabilidade dos dados (total de 97%). Os espécimes capturados neste estudo são pequenos em tamanho e peso e reprodutivamente imaturos, com maior ocorrência de fêmeas e em maior número no período seco.

Genyatremus luteus is specie of commercial importance in the Pará state. In this study, the population biology of G. luteus was investigated in an estuary of the Eastern Amazon, the collections occurred from October 2012 to October 2013, each month, in the tidal channel (Furo grande), with block net. In the laboratory the individuals were gauged the lengths: total, standard, head and height, in addition to weight being recorded. After ventral incision and gonads removal, the gonadal stage was defined for females and males macroscopically. 460 individuals were captured whose sizes and weights ranged from 4.50 to 21.40 cm and 1.36 and 148.26 g. The relative frequencies of females and males were different than expected from 1: 1 (x2: 8.90, p <0.01), differing significantly by sex and size class (p <0.01). The mean size (CT) presented differences significant in relation to sex (F = 22.71, p <0.01), month (F = 35.80, p <0.01) (P <0.01), gonadal stage (F = 29.77, p <0.01) and gonadal stage by seasonal period (F = 2.37, p <0.05). The wet weight did not differ statistically by gonadal stage, seasonal period and sex. The ordering diagram showed that the turbidity was the variable that responded by the greater variability in the data (total of 97%). The specimens captured in this study are small in size and weight and reproductively immature, with higher occurrence of females, in greater numbers in the dry period.

Variação temporal da captura comercial do peixe pedra, Genyatremus luteus, desembarcado em um pólo pesqueiro da costa norte do Brasil Península de Ajuruteua Bragança - PA / Temporal variation of commercial catches of torroto grunt, Genyatremus luteus in fishing pole of Brazilian North Coast - Peninsula of Ajuruteua Bragança - PA

Brazilian Northern coast includes the states of Amapá, Pará and Maranhão, characterized by high fishing productivity. Among of captured resources is Genyatremus luteus (Torroto grunt). This study aims to analyze the seasonal variation of the fishing and as the behavior of the precipitation it can influence the production in the North coast of Brazil. Data were collected during April 2008 to March of 2011 in fishing vessel and eleven ports of Bragança fishing land. Data of landings were obtained by census method and seasonal period data were given up by the National Institute of Meteorology (INMET). Values of abundance were designed by capture for unit of effort (CPUE). Data analysis was done using softwares STASOFT® 10.0 and Microsoft EXCEL 2010. A total of 3,291 fishing landings were registered, accomplished by 305 vessels, producing a total of 323 t of Torroto grunt. The largest production average occurred in dry-rainy transition period (TSC) (F = 14.5; p<0.01). CPUE by vessel type and seasonal period obtained larger significance in small load vessels (BPP) in TSC period (F = 4.0; p<0.01). The categories of fishing gear higher average production were mobile gillnets (F = 60.7; p<0.01). The seasonal variation has great influence on the productivity of the studied species.

A costa Norte do Brasil, que compreende os estados do Amapá, Pará e Maranhão, é caracterizada por ser uma região muito produtiva do ponto de vista pesqueiro. Dentre os recursos capturados, encontra-se a espécie Genyatremus luteus (peixe-pedra). Neste estudo foi analisada a variação sazonal da pesca desta espécie e como o comportamento da precipitação pode influenciar a produção na costa Norte do Brasil. Os dados provenientes das embarcações e desembarques foram obtidos por formulários de catalogação de forma censitária em onze portos de desembarque do município de Bragança, no período de abril de 2008 a março de 2011, e as informações pluviométricas foram cedidas pelo Instituto Nacional de Meteorologia (INMET). Foram estimados os valores de abundância a partir da captura por unidade de esforço (CPUE). Para a análise dos resultados, foram utilizados os programas STASOFT® 10.0 e Microsoft EXCEL 2010. Foram registrados 3.291 desembarques, realizados por 305 embarcações, produzindo um total de 323 t de peixe-pedra. A maior média de produção ocorreu no período de transição seco-chuvoso (TSC)(F = 14,5; p<0,01). A CPUE por tipo de barco e período sazonal obteve maior significância embarcos de pequeno porte (BPP) no período TSC (F = 4,0; p<0,01). As categorias de petrecho de pesca com maior média de produção foram as redes móveis (F = 60,7; p<0,01). A variação sazonal possui grande influência na produtividade da espécie estudada.

Variação temporal da captura comercial do peixe pedra, Genyatremus luteus, desembarcado em um pólo pesqueiro da costa norte do Brasil Península de Ajuruteua Bragança - PA / Temporal variation of commercial catches of torroto grunt, Genyatremus luteus in fishing pole of Brazilian North Coast - Peninsula of Ajuruteua Bragança - PA

Brazilian Northern coast includes the states of Amapá, Pará and Maranhão, characterized by high fishing productivity. Among of captured resources is Genyatremus luteus (Torroto grunt). This study aims to analyze the seasonal variation of the fishing and as the behavior of the precipitation it can influence the production in the North coast of Brazil. Data were collected during April 2008 to March of 2011 in fishing vessel and eleven ports of Bragança fishing land. Data of landings were obtained by census method and seasonal period data were given up by the National Institute of Meteorology (INMET). Values of abundance were designed by capture for unit of effort (CPUE). Data analysis was done using softwares STASOFT® 10.0 and Microsoft EXCEL 2010. A total of 3,291 fishing landings were registered, accomplished by 305 vessels, producing a total of 323 t of Torroto grunt. The largest production average occurred in dry-rainy transition period (TSC) (F = 14.5; p<0.01). CPUE by vessel type and seasonal period obtained larger significance in small load vessels (BPP) in TSC period (F = 4.0; p<0.01). The categories of fishing gear higher average production were mobile gillnets (F = 60.7; p<0.01). The seasonal variation has great influence on the productivity of the studied species.(AU)

A costa Norte do Brasil, que compreende os estados do Amapá, Pará e Maranhão, é caracterizada por ser uma região muito produtiva do ponto de vista pesqueiro. Dentre os recursos capturados, encontra-se a espécie Genyatremus luteus (peixe-pedra). Neste estudo foi analisada a variação sazonal da pesca desta espécie e como o comportamento da precipitação pode influenciar a produção na costa Norte do Brasil. Os dados provenientes das embarcações e desembarques foram obtidos por formulários de catalogação de forma censitária em onze portos de desembarque do município de Bragança, no período de abril de 2008 a março de 2011, e as informações pluviométricas foram cedidas pelo Instituto Nacional de Meteorologia (INMET). Foram estimados os valores de abundância a partir da captura por unidade de esforço (CPUE). Para a análise dos resultados, foram utilizados os programas STASOFT® 10.0 e Microsoft EXCEL 2010. Foram registrados 3.291 desembarques, realizados por 305 embarcações, produzindo um total de 323 t de peixe-pedra. A maior média de produção ocorreu no período de transição seco-chuvoso (TSC)(F = 14,5; p<0,01). A CPUE por tipo de barco e período sazonal obteve maior significância embarcos de pequeno porte (BPP) no período TSC (F = 4,0; p<0,01). As categorias de petrecho de pesca com maior média de produção foram as redes móveis (F = 60,7; p<0,01). A variação sazonal possui grande influência na produtividade da espécie estudada.(AU)

Biología reproductiva de Anisotremus interruptus (Perciformes: Haemulidae) en el Pacífico central mexicano / Reproductive biology of Anisotremus interruptus (Perciformes: Haemulidae) in the Mexican Central Pacific

Reproductive biology of Anisotremus interruptus (Perciformes: Haemulidae) in the Mexican Central Pacific. Anisotremus interruptus is a widely distributed and commercially important species in the Eastern Pacific. A multi-year research on the reproduction of this species was carried out in coastal waters of Jalisco, Mexico. For this purpose, monthly samples were gathered with gillnets of different mesh sizes from 1998-2008. A total of 1 090 individuals were collected with a total length range between 15.6-61.0cm. Significant differences from expected 1:1 ratio were found for sex ratios in the total sample and for each size class, but not when comparisons among months and years were done. Temporal variations of the gonadosomatic index and proportions of maturation stages suggest that the main reproductive period is from February to May, although some less intensive spawning events were observed in other months. Seven stages of oocytes development were identified. Oocytes in different stages of development were identified in ovaries classified as mature, suggesting an asynchronic type of gonad development. Mean maturation length (L50) was 31.0 for females and 29.7cm for males. The internal organization of testes is of lobular type. Rev. Biol. Trop. 60 (2): 709-720. Epub 2012 June 01.

Anisotremus interruptus es una especie de importancia económica que se distribuye ampliamente en el Pacífico oriental. Para investigar las características de la reproducción de esta especie, se realizó un estudio a lo largo de varios años en la costa de Jalisco, México. Para este fin, se tomaron muestras entre 1998 y 2008 con redes de enmalle de diferente luz de malla. Asimismo, se recolectaron en total 1 090 organismos que presentaron un intervalo de longitud total de 15.6-61.0cm. Además, se observó una diferencia significativa con respecto al valor esperado de 1:1 en la proporción de hembras y machos para todos los organismos recolectados y por clase de talla, pero no se encontró diferencia en dicha proporción en los análisis entre meses y entre años. La distribución temporal del índice gonadosomático y de la proporción de estadios de maduración gonadal sugieren que el periodo de reproducción en A. interruptus se concentra principalmente entre febrero-mayo, aunque se registraron desoves de menor intensidad en otros meses. También, se identificaron siete fases de desarrollo de los ovocitos. En ovarios de estadio maduro, se observaron ovocitos en diferente fase de desarrollo, lo cual sugiere que el desarrollo ovárico es de tipo asincrónico. La organización interna del testículo es del tipo lobular. La longitud de maduración sexual (L50) para las hembras fue de 31.0cm y para los machos de 29.7cm.