Feeding strategy of the introduced Astronotus crassipinnis (Cichlidae) in upper Paraná river floodplain / Estratégia alimentar do introduzido Astronotus crassipinnis (Cichlidae) na planície de inundação do alto rio Paraná

The cichlid Astronotus crassipinnis (Heckel, 1840) known as "oscar" or "apaiari" is native to the Amazon basin and presents an omnivorous feeding habit, with a tendency to carnivory. The species was introduced in the upper Paraná River floodplain, where the trophic strategies adopted by the species are not well-known. The objective of this study was to characterize the diet of A. crassipinnis in different size classes to identify ontogenetic differences in diet composition and to determine its feeding behavior in the invaded floodplain. In addition, we experimentally compared the feeding behavior of A. crassipinnis with Hoplias sp. 2, a native piscivorous. We evaluated the predation rate of the two species with different prey (fish and shrimp). Astronotus crassipinnis consumed items from several trophic levels in the juvenile stage, characterizing an omnivore feeding. In the adult stage, A. crassipinnis displayed a specialist strategy in which fish and mollusks dominated the diet. Under controlled conditions, A. crassipinnis consumed more shrimp than Hoplias sp. 2. The preference for shrimp during the experiment contrasted to its feeding in natural environments, showing the potential trophic plasticity of A. crassipinnis. The piscivorous habit in the invaded environment can be considered a trophic strategy of A. crassipinnis, which feeds on an abundant resource in the upper Paraná River floodplain. In conclusion, the ontogenetic diet shifts and the trophic opportunism of the carnivore adults can be the strategies used by the species to invade and settle the floodplain. The piscivorous strategy of A. crassipinnis may impact fish biodiversity, altering ecosystem functioning.

Astronotus crassipinnis (Heckel, 1840), conhecido como "oscar" ou "apaiari", é nativo da bacia Amazônica e apresenta hábito alimentar onívoro, com tendência à carnivoria. A espécie foi introduzida na planície de inundação do alto rio Paraná, onde as estratégias tróficas adotadas pela espécie não são bem conhecidas. O objetivo deste estudo foi caracterizar a dieta de A. crassipinis em diferentes classes de comprimento para identificar diferenças ontogenéticas na composição da dieta e determinar seu comportamento alimentar na planície de inundação invadida. Em adição, nós comparamos experimentalmente o comportamento alimentar de A. crassipinnis com Hoplias sp. 2, um piscívoro nativo. Avaliamos a taxa de predação das duas espécies com presas diferentes (peixes e camarões). Astronotus crassipinnis consumiu itens de diferentes níveis tróficos no estágio juvenil, caracterizando uma alimentação onívora. No estágio adulto, A. crassipinnis apresentou uma estratégia especialista em que peixes e moluscos dominaram a dieta. Em condições controladas, A. crassipinnis consumiu mais camarões que Hoplias sp. 2. A preferência por camarão durante o experimento em contraste com sua alimentação em ambientes naturais evidencia a alta plasticidade trófica de A. crassipinnis. O hábito piscívoro no ambiente invadido pode ser considerado uma estratégia trófica de A. crassipinnis, que se alimenta de um recurso abundante na planície do alto Rio Paraná. Em conclusão, as mudanças ontogenéticas na dieta e o oportunismo trófico dos adultos podem ser as estratégias utilizadas pela espécie para invadir e colonizar a planície de inundação. A estratégia piscívora de A. crassipinnis pode impactar a biodiversidade de peixes, alterando o funcionamento do ecossistema.

Comparative compositional and functional venomic profiles among venom specimens from juvenile, subadult and adult Russell's viper ( Daboia siamensis ): correlation with renal pathophysiology in experimental rabbits

Abstract Background: Eastern Russell's viper (Daboia siamensis) is one of the most medically significant snakes responsible for the development of acute renal failure. However, variation of the clinical picture and renal pathophysiology following bites by young and adult D. siamensis have not been elucidated. Methods: In this study, we analyzed the venomic profiles of D. siamensis at different maturation stages of juvenile, subadult and adult groups. The same pooled venom from each group was subjected to enzymatic, electrophoretic and proteomic analysis, including sublethal toxicity (0.1 mg/kg iv.) examined on bodily functions by comparing the venom compositional and functional profiles among venom specimens from juvenile, subadult and adult D. siamensis by correlating them with the renal pathophysiology in experimental rabbits. Results: The comparative studies revealed that juvenile venom possessed higher phospholipase A2 , metalloproteinase and serine proteinase levels, while subadult and adult venoms contained more L-amino acid oxidase, phosphodiesterase, the Kunitz-type serine protease inhibitor, disintegrin families and endothelial growth factor. An in vivo study revealed that the adult and subadult venoms caused persistent hypotension and bradycardia, while thrombocytopenia was a more characteristic effect of juvenile venom. All venom age groups showed significant reductions in renal hemodynamics and electrolyte excretions. The juvenile venom caused a higher tubulonephrosis lesion score than adult and subadult venoms. Conclusions: The D. siamensis venom shows an ontogenetic shift in its compositions and activities. Renal function alterations after envenomation depend on either the synergistic actions of different venom components or the disproportionate expression between the concentrations of enzymatic and non-enzymatic proteins in each age venom group. The high proportion of enzymatic toxin proteins in the juvenile venom results in greater nephrotoxicity.(AU)

Sagitta otolith of three demersal species in a tropical environment

Abstract The objective of this study was to describe the morphology and morphometry of saggitta otoliths of Polydactylus virginicus, Menticirrhus cuiaranensis and Conodon nobilis in a tropical environment. Fishes were caught with rod and reel in competitive fishing events promoted in 2014-2015 along the coast of Sergipe. A total of 174 pairs of sagitta otoliths of P. virginicus, 181 of M. cuiaranensis and 77 of C. nobilis was extracted. In general, the sagitta otoliths of all three species analyzed here presented different morphology and shape indices. The permutational multivariate analysis of variance (PERMANOVA) demonstrated significant differences among species and ontogenetic phases within each species using morphometry and shape indices. The linear discriminant analysis (LDA) presented a 98.3% correct reclassification of the otoliths by species.

Sagitta otolith of three demersal species in a tropical environment

Abstract The objective of this study was to describe the morphology and morphometry of saggitta otoliths of Polydactylus virginicus, Menticirrhus cuiaranensis and Conodon nobilis in a tropical environment. Fishes were caught with rod and reel in competitive fishing events promoted in 2014-2015 along the coast of Sergipe. A total of 174 pairs of sagitta otoliths of P. virginicus, 181 of M. cuiaranensis and 77 of C. nobilis was extracted. In general, the sagitta otoliths of all three species analyzed here presented different morphology and shape indices. The permutational multivariate analysis of variance (PERMANOVA) demonstrated significant differences among species and ontogenetic phases within each species using morphometry and shape indices. The linear discriminant analysis (LDA) presented a 98.3% correct reclassification of the otoliths by species.

Ontogenetic skull variation in an Amazonian population of lowland tapir, Tapirus terrestris (Mammalia: Perissodactyla) in the department of Loreto, Peru

RESUMEN Se midió, analizó y comparó 54 cráneos de tapir sudamericano, Tapirus terrestris recolectados en el departamento de Loreto, Perú, para investigar el desarrollo craneal de esta especie. Se realizaron análisis univariados, multivariados y alométricos de los cráneos utilizando 32 variables mediante morfometría tradicional. Se detectó una variación significativa de la forma del cráneo entre clases ontogenéticas. Los individuos más jóvenes (clase I, n = 22) mostraron mayor variación que subadultos y adultos (clases II, n = 23 y III, n = 9), pero sin evidencia de dimorfismo sexual (machos = 35, hembras = 19). Un análisis de componentes principales y un análisis de función discriminante mostraron una separación casi completa de las clases ontogenéticas. El análisis alométrico indicó una tendencia de crecimiento craneal desproporcionado. Todas nuestras muestras provienen de la misma población que vive bajo la misma condición ecológica, lo que elimina el efecto de confusión de variables relacionadas con el hábitat sobre el patrón de variaciones ontogenéticas de esta estructura anatómica.

ABSTRACT The skulls of 54 specimens of the South American tapir, Tapirus terrestris collected in the department of Loreto, Peru were measured, analyzed and compared to investigate skull development of this species. Univariate, multivariate and allometric analyses were performed using 32 skull variables through traditional morphometrics. Significant skull shape variation was detected among ontogenetic classes. Young individuals (class I, n = 22) showed higher variation than subadults and adults (class II, n = 23 and class III, n = 9), without evidence of sexual dimorphism (males = 35, females = 19). Principal component analyses and discriminant function analysis showed almost complete separation of the age classes. Allometric analysis indicated a tendency of unproportioned cranial growth. All our samples come from the same population living under the same ecological condition, which eliminates the effect of confounding variables related to habitat on the pattern of ontogenetic variation of this anatomical structure.

Ontogenetic skull variation in an Amazonian population of lowland tapir, Tapirus terrestris (Mammalia: Perissodactyla) in the department of Loreto, Peru / Variación ontogenética de cráneos en una población amazónica del tapirsudamericano, Tapirus terrestris (Mammalia: Perissodactyla) en Loreto, Perú

The skulls of 54 specimens of the South American tapir, Tapirus terrestris collected in the department of Loreto, Peru were measured, analyzed and compared to investigate skull development of this species. Univariate, multivariate and allometric analyses were performed using 32 skull variables through traditional morphometrics. Significant skull shape variation was detected among ontogenetic classes. Young individuals (class I, n = 22) showed higher variation than subadults and adults (class II, n = 23 and class III, n = 9), without evidence of sexual dimorphism (males = 35, females = 19). Principal component analyses and discriminant function analysis showed almost complete separation of the age classes. Allometric analysis indicated a tendency of unproportioned cranial growth. All our samples come from the same population living under the same ecological condition, which eliminates the effect of confounding variables related to habitat on the pattern of ontogenetic variation of this anatomical structure.

Se midió, analizó y comparó 54 cráneos de tapir sudamericano, Tapirus terrestris recolectados en el departamento de Loreto, Perú, para investigar el desarrollo craneal de esta especie. Se realizaron análisis univariados, multivariados y alométricos de los cráneos utilizando 32 variables mediante morfometría tradicional. Se detectó una variación significativa de la forma del cráneo entre clases ontogenéticas. Los individuos más jóvenes (clase I, n = 22) mostraron mayor variación que subadultos y adultos (clases II, n = 23 y III, n = 9), pero sin evidencia de dimorfismo sexual (machos = 35, hembras = 19). Un análisis de componentes principales y un análisis de función discriminante mostraron una separación casi completa de las clases ontogenéticas. El análisis alométrico indicó una tendencia de crecimiento craneal desproporcionado. Todas nuestras muestras provienen de la misma población que vive bajo la misma condición ecológica, lo que elimina el efecto de confusión de variables relacionadas con el hábitat sobre el patrón de variaciones ontogenéticas de esta estructura anatómica.

Ontogenetic skull variation in an Amazonian population of lowland tapir, Tapirus terrestris (Mammalia: Perissodactyla) in the department of Loreto, Peru / Variación ontogenética de cráneos en una población amazónica del tapirsudamericano, Tapirus terrestris (Mammalia: Perissodactyla) en Loreto, Perú

The skulls of 54 specimens of the South American tapir, Tapirus terrestris collected in the department of Loreto, Peru were measured, analyzed and compared to investigate skull development of this species. Univariate, multivariate and allometric analyses were performed using 32 skull variables through traditional morphometrics. Significant skull shape variation was detected among ontogenetic classes. Young individuals (class I, n = 22) showed higher variation than subadults and adults (class II, n = 23 and class III, n = 9), without evidence of sexual dimorphism (males = 35, females = 19). Principal component analyses and discriminant function analysis showed almost complete separation of the age classes. Allometric analysis indicated a tendency of unproportioned cranial growth. All our samples come from the same population living under the same ecological condition, which eliminates the effect of confounding variables related to habitat on the pattern of ontogenetic variation of this anatomical structure.(AU)

Se midió, analizó y comparó 54 cráneos de tapir sudamericano, Tapirus terrestris recolectados en el departamento de Loreto, Perú, para investigar el desarrollo craneal de esta especie. Se realizaron análisis univariados, multivariados y alométricos de los cráneos utilizando 32 variables mediante morfometría tradicional. Se detectó una variación significativa de la forma del cráneo entre clases ontogenéticas. Los individuos más jóvenes (clase I, n = 22) mostraron mayor variación que subadultos y adultos (clases II, n = 23 y III, n = 9), pero sin evidencia de dimorfismo sexual (machos = 35, hembras = 19). Un análisis de componentes principales y un análisis de función discriminante mostraron una separación casi completa de las clases ontogenéticas. El análisis alométrico indicó una tendencia de crecimiento craneal desproporcionado. Todas nuestras muestras provienen de la misma población que vive bajo la misma condición ecológica, lo que elimina el efecto de confusión de variables relacionadas con el hábitat sobre el patrón de variaciones ontogenéticas de esta estructura anatómica.(AU)

Morphological divergences as drivers of diet segregation between two sympatric species of Serrapinnus (Characidae: Cheirodontinae) in macrophyte stands in a neotropical floodplain lake

Diet and morphology of Serrapinnus notomelas and Serrapinnus sp.1 were investigated across ontogeny, as a way to elucidate the key elements linked to the resource partitioning (a main driver for species coexistence). Fish sampling was conducted monthly between October 2010 and March 2012. Individuals were captured, identified, and classified into juvenile or adult. Our results show ontogenetic and interspecific differences in feeding abilities and morphological traits. Differences in body shape (relative area of the dorsal fin, length of head, height of the caudal peduncle, the aspect ratio of the pectoral and pelvic fin) favored divergent swimming performances (more maneuverability in S. notomelas and continuous swimming to Serrapinnus sp.1). We also observed divergences in trophic apparatus traits and correlations with different diets. In this context, it is highlighted that understanding the relationship between morphology and diet can assist in elucidating the processes that permeate the coexistence between sympatric species, and between ontogenetic periods. Besides, the relevant contribution of the measures of the trophic apparatus (gill raker length, the number of teeth cuspids, and intestinal coefficient) in trophic segregation seems to be a strong evidence in favor of the proposed discriminatory and predictive capacities of these traits.(AU)

Dieta e morfologia de Serrapinnus notomelas e Serrapinnus sp.1 foram investigadas ao longo da ontogenia, como forma de elucidar os principais elementos ligados à partição de recursos (principal fator para a coexistência entre espécies). Foram realizadas coletas de peixes mensalmente entre outubro de 2010 e março de 2012. Os indivíduos foram capturados, identificados e classificados em juvenis ou adultos. Nossos resultados mostram diferenças ontogenéticas e interespecíficas na alimentação e características morfológicas. Diferenças na forma corporal (área da nadadeira dorsal, comprimento da cabeça, altura do pedúnculo caudal, proporção das nadadeiras peitorais e pélvicas) favoreceram desempenhos de natação divergentes (maior manobrabilidade para S. notomelas e natação contínua para Serrapinnus sp.1). Também observamos divergências nas características do aparato trófico e correlações com diferentes dietas. Nesse contexto, destaca-se que compreender a relação entre morfologia e dieta pode auxiliar na elucidação dos processos que permeiam a coexistência entre espécies simpátricas e entre períodos ontogenéticos. Além disso, a relevante contribuição das medidas do aparato trófico (número de cúspide nos dentes, rastros branquiais e coeficiente intestinal) na segregação trófica parece ser uma forte evidência a favor das propostas de capacidades discriminatórias e preditivas dessas características.(AU)

Morphological divergences as drivers of diet segregation between two sympatric species of Serrapinnus (Characidae: Cheirodontinae) in macrophyte stands in a neotropical floodplain lake

Diet and morphology of Serrapinnus notomelas and Serrapinnus sp.1 were investigated across ontogeny, as a way to elucidate the key elements linked to the resource partitioning (a main driver for species coexistence). Fish sampling was conducted monthly between October 2010 and March 2012. Individuals were captured, identified, and classified into juvenile or adult. Our results show ontogenetic and interspecific differences in feeding abilities and morphological traits. Differences in body shape (relative area of the dorsal fin, length of head, height of the caudal peduncle, the aspect ratio of the pectoral and pelvic fin) favored divergent swimming performances (more maneuverability in S. notomelas and continuous swimming to Serrapinnus sp.1). We also observed divergences in trophic apparatus traits and correlations with different diets. In this context, it is highlighted that understanding the relationship between morphology and diet can assist in elucidating the processes that permeate the coexistence between sympatric species, and between ontogenetic periods. Besides, the relevant contribution of the measures of the trophic apparatus (gill raker length, the number of teeth cuspids, and intestinal coefficient) in trophic segregation seems to be a strong evidence in favor of the proposed discriminatory and predictive capacities of these traits.(AU)

Dieta e morfologia de Serrapinnus notomelas e Serrapinnus sp.1 foram investigadas ao longo da ontogenia, como forma de elucidar os principais elementos ligados à partição de recursos (principal fator para a coexistência entre espécies). Foram realizadas coletas de peixes mensalmente entre outubro de 2010 e março de 2012. Os indivíduos foram capturados, identificados e classificados em juvenis ou adultos. Nossos resultados mostram diferenças ontogenéticas e interespecíficas na alimentação e características morfológicas. Diferenças na forma corporal (área da nadadeira dorsal, comprimento da cabeça, altura do pedúnculo caudal, proporção das nadadeiras peitorais e pélvicas) favoreceram desempenhos de natação divergentes (maior manobrabilidade para S. notomelas e natação contínua para Serrapinnus sp.1). Também observamos divergências nas características do aparato trófico e correlações com diferentes dietas. Nesse contexto, destaca-se que compreender a relação entre morfologia e dieta pode auxiliar na elucidação dos processos que permeiam a coexistência entre espécies simpátricas e entre períodos ontogenéticos. Além disso, a relevante contribuição das medidas do aparato trófico (número de cúspide nos dentes, rastros branquiais e coeficiente intestinal) na segregação trófica parece ser uma forte evidência a favor das propostas de capacidades discriminatórias e preditivas dessas características.(AU)

Sagitta otolith of three demersal species in a tropical environment

The objective of this study was to describe the morphology and morphometry of saggitta otoliths of Polydactylus virginicus, Menticirrhus cuiaranensis and Conodon nobilis in a tropical environment. Fishes were caught with rod and reel in competitive fishing events promoted in 2014-2015 along the coast of Sergipe. A total of 174 pairs of sagitta otoliths of P. virginicus, 181 of M. cuiaranensis and 77 of C. nobilis was extracted. In general, the sagitta otoliths of all three species analyzed here presented different morphology and shape indices. The permutational multivariate analysis of variance (PERMANOVA) demonstrated significant differences among species and ontogenetic phases within each species using morphometry and shape indices. The linear discriminant analysis (LDA) presented a 98.3% correct reclassification of the otoliths by species.(AU)

Redescription of the Rio skate Rioraja agassizii (Rajiformes: Arhynchobatidae) with notes on internal anatomy and intraspecific variation

Rioraja agassizii belongs to the monotypic genus Rioraja and differs from the other Riorajini species of the genus Atlantoraja by the shape of anterior nasal flap, squamation, clasper skeleton, body measurements and color pattern. Although R. agassizii is a well-known species, commonly captured in inshore waters of the southwestern Atlantic, its external morphology and internal anatomy have never been fully described and little is known on intraspecific variation within the species. Juvenile and adult, male and female specimens were examined, measured and dissected. Herein, we redescribe the species and present detailed descriptions and illustrations of external morphology, neurocranium, jaws, hyoid and gill arches, and pelvic fin and girdle. Additionally, notes on sexual dimorphism and ontogenetic differences in coloration, body and cranial measurements, and dermal denticles are provided.(AU)

Rioraja agassizii pertence ao gênero monotípico Rioraja e difere das demais espécies da tribo Riorajini classificadas no gênero Atlantoraja pelo formato da aba nasal anterior, escamas, esqueleto do clásper, medidas corpóreas e padrão de coloração. Embora R. agassizii seja uma espécie bem conhecida, comumente capturada em águas costeiras do Atlântico Sul Ocidental, sua morfologia externa e anatomia interna não foram totalmente descritas e pouco se sabe sobre a variação intraespecífica nesta espécie. Espécimes juvenis, adultos, machos e fêmeas foram examinados, medidos e dissecados. Neste estudo, a espécie é redescrita e descrições detalhadas e ilustrações da morfologia externa, neurocrânio, maxilas, arcos hioide e branquiais, nadadeira e cintura pélvicas são apresentadas. Adicionalmente, notas sobre dimorfismo sexual e variação ontogenética na coloração, medidas corpóreas e craniais, e dentículos dérmicos são fornecidas.(AU)

Redescription of the Rio skate Rioraja agassizii (Rajiformes: Arhynchobatidae) with notes on internal anatomy and intraspecific variation

Rioraja agassizii belongs to the monotypic genus Rioraja and differs from the other Riorajini species of the genus Atlantoraja by the shape of anterior nasal flap, squamation, clasper skeleton, body measurements and color pattern. Although R. agassizii is a well-known species, commonly captured in inshore waters of the southwestern Atlantic, its external morphology and internal anatomy have never been fully described and little is known on intraspecific variation within the species. Juvenile and adult, male and female specimens were examined, measured and dissected. Herein, we redescribe the species and present detailed descriptions and illustrations of external morphology, neurocranium, jaws, hyoid and gill arches, and pelvic fin and girdle. Additionally, notes on sexual dimorphism and ontogenetic differences in coloration, body and cranial measurements, and dermal denticles are provided.(AU)

Rioraja agassizii pertence ao gênero monotípico Rioraja e difere das demais espécies da tribo Riorajini classificadas no gênero Atlantoraja pelo formato da aba nasal anterior, escamas, esqueleto do clásper, medidas corpóreas e padrão de coloração. Embora R. agassizii seja uma espécie bem conhecida, comumente capturada em águas costeiras do Atlântico Sul Ocidental, sua morfologia externa e anatomia interna não foram totalmente descritas e pouco se sabe sobre a variação intraespecífica nesta espécie. Espécimes juvenis, adultos, machos e fêmeas foram examinados, medidos e dissecados. Neste estudo, a espécie é redescrita e descrições detalhadas e ilustrações da morfologia externa, neurocrânio, maxilas, arcos hioide e branquiais, nadadeira e cintura pélvicas são apresentadas. Adicionalmente, notas sobre dimorfismo sexual e variação ontogenética na coloração, medidas corpóreas e craniais, e dentículos dérmicos são fornecidas.(AU)

Ontogenetic and sexual variation in the sagitta otolith of Menticirrhus americanus (Teleostei; Sciaenidae) (Linnaeus, 1758) in a subtropical environment

This study aimed to verify variations in the form of the sagitta otolith of Menticirrhus americanus as to their ontogeny, sex and stage of such structure. Ontogenetically were found significant differences (p < 0.05) for all shape indices (aspect ratios, shape factor, rectangularity, ellipticity, relative surface of sulcus acusticus) and also in the wavelet of the otolith. The CVA presented a 98.6% correct reclassification of the otolith between interval class. Sexual variations were found in the wavelet and in the relative surface of sulcus acusticus index. Between adult females and young females, differences were not detected in the wavelet and rectangularity, but significant differences were found in all other shape indices. The CVA presented a 79.6% correct reclassification of the otolith of the sexes and stages of life sampled. Young females and adults females showed highest correct percentage of classification. The results of this study demonstrate for the first time the influence of the ontogenetic variation and sexual in the form of the otoliths.

Ontogenetic and sexual variation in the sagitta otolith of Menticirrhus americanus (Teleostei; Sciaenidae) (Linnaeus, 1758) in a subtropical environment

This study aimed to verify variations in the form of the sagitta otolith of Menticirrhus americanus as to their ontogeny, sex and stage of such structure. Ontogenetically were found significant differences (p < 0.05) for all shape indices (aspect ratios, shape factor, rectangularity, ellipticity, relative surface of sulcus acusticus) and also in the wavelet of the otolith. The CVA presented a 98.6% correct reclassification of the otolith between interval class. Sexual variations were found in the wavelet and in the relative surface of sulcus acusticus index. Between adult females and young females, differences were not detected in the wavelet and rectangularity, but significant differences were found in all other shape indices. The CVA presented a 79.6% correct reclassification of the otolith of the sexes and stages of life sampled. Young females and adults females showed highest correct percentage of classification. The results of this study demonstrate for the first time the influence of the ontogenetic variation and sexual in the form of the otoliths.(AU)

Feeding habits of Lutjanus synagris (Teleostei: Lutjanidae) in the Amazon Coast of the northeast region of Brazil / Hábitos alimentares de Lutjanus synagris (Teleostei: Lutjanidae) na Costa Amazônica da região nordeste do Brasil

The feeding habit of lane snapper Lutjanus synagris was analyzed qualitatively and quantitatively, related to seasonality, its ontogenetic development, and the relationship between food and biotic and abiotic conditions on the Amazon Coast of Maranhão, between June 2018 and May 2019. Numerical, gravimetric, and ecological index methods were used to show the relative importance or preference of a category or food item in the diet. The food composition was studied related to the sex, size of the predator and seasonality. Of 359 stomachs sampled, 54 were empty due to regurgitation and presented a vacuity coefficient (Cv%) of 15.04%. In the analysis of diets between the sexes, it was possible to identify a greater participation of fish (30.43%) and Crabs (26.10%) for females, Shrimp (36.23%) and Organic Matter Not Identified (OMNI) (18.84%) in males. The diet showed spatial differences in length distributions. The analysis of stomach contents showed the presence synthetic materials (mesoplastics ranging from 5.0 mm to 2.5 cm) in 5.52% of the samples. The main food items found were from the Brachyura and Caridea species. The results clearly demonstrate that lane snapper prefers benthic prey, presenting a carnivorous and generalist-opportunistic habit. Its diet is also composed of demersal-pelagic species, such as Cephalopods and Teleost fish.

O hábito alimentar do ariacó Lutjanus synagris foi analisado qualitativamente e quantitativamente, relacionados à sazonalidade, seu desenvolvimento ontogenético e a relação entre alimento e condições bióticas e abióticas na Costa Amazônica do Maranhão, entre junho 2018 e maio de 2019. Métodos numéricos, gravimétricos e índices ecológicos foram usados para mostrar a importância ou preferência relativa de uma determinada categoria ou item alimentar na dieta. Foi analisada a variação na composição alimentar em relação ao sexo, tamanho do predador e sazonalidade. Dos 359 estômagos amostrados, 54 estavam vazios por regurgitação e apresentaram coeficiente de vacuidade (Cv%) de 15,04%. Na análise das dietas entre os sexos, foi possível identificar uma maior participação de peixes (30,43%) e caranguejos (26,10%) para fêmeas, camarões (36,23%) e Material Orgânico Não Identificado (OMNI) (18,84%) nos machos. A dieta da espécie mostrou diferenças espaciais particulares nas distribuições de comprimento. A análise do conteúdo estomacal mostrou presença materiais sintéticos (mesoplásticos variando de 5 mm a 2,5 cm) em 5,52% das amostras. Os principais itens alimentares encontrados foram de espécies dos grupos Brachyura e Caridea. Os resultados claramente demonstram que o ariacó tem preferência por presas bentônicas, apresentando hábitos carnívoro e...

Feeding habits of Lutjanus synagris (Teleostei: Lutjanidae) in the Amazon Coast of the northeast region of Brazil / Hábitos alimentares de Lutjanus synagris (Teleostei: Lutjanidae) na Costa Amazônica da região nordeste do Brasil

The feeding habit of lane snapper Lutjanus synagris was analyzed qualitatively and quantitatively, related to seasonality, its ontogenetic development, and the relationship between food and biotic and abiotic conditions on the Amazon Coast of Maranhão, between June 2018 and May 2019. Numerical, gravimetric, and ecological index methods were used to show the relative importance or preference of a category or food item in the diet. The food composition was studied related to the sex, size of the predator and seasonality. Of 359 stomachs sampled, 54 were empty due to regurgitation and presented a vacuity coefficient (Cv%) of 15.04%. In the analysis of diets between the sexes, it was possible to identify a greater participation of fish (30.43%) and Crabs (26.10%) for females, Shrimp (36.23%) and Organic Matter Not Identified (OMNI) (18.84%) in males. The diet showed spatial differences in length distributions. The analysis of stomach contents showed the presence synthetic materials (mesoplastics ranging from 5.0 mm to 2.5 cm) in 5.52% of the samples. The main food items found were from the Brachyura and Caridea species. The results clearly demonstrate that lane snapper prefers benthic prey, presenting a carnivorous and generalist-opportunistic habit. Its diet is also composed of demersal-pelagic species, such as Cephalopods and Teleost fish.(AU)

O hábito alimentar do ariacó Lutjanus synagris foi analisado qualitativamente e quantitativamente, relacionados à sazonalidade, seu desenvolvimento ontogenético e a relação entre alimento e condições bióticas e abióticas na Costa Amazônica do Maranhão, entre junho 2018 e maio de 2019. Métodos numéricos, gravimétricos e índices ecológicos foram usados para mostrar a importância ou preferência relativa de uma determinada categoria ou item alimentar na dieta. Foi analisada a variação na composição alimentar em relação ao sexo, tamanho do predador e sazonalidade. Dos 359 estômagos amostrados, 54 estavam vazios por regurgitação e apresentaram coeficiente de vacuidade (Cv%) de 15,04%. Na análise das dietas entre os sexos, foi possível identificar uma maior participação de peixes (30,43%) e caranguejos (26,10%) para fêmeas, camarões (36,23%) e Material Orgânico Não Identificado (OMNI) (18,84%) nos machos. A dieta da espécie mostrou diferenças espaciais particulares nas distribuições de comprimento. A análise do conteúdo estomacal mostrou presença materiais sintéticos (mesoplásticos variando de 5 mm a 2,5 cm) em 5,52% das amostras. Os principais itens alimentares encontrados foram de espécies dos grupos Brachyura e Caridea. Os resultados claramente demonstram que o ariacó tem preferência por presas bentônicas, apresentando hábitos carnívoro e...(AU)

Um exemplar muito jovem de Mazama sp. encontrado na Gruta Cuvieri, região de Lagoa Santa, estado de Minas Gerais, Brasil / A very young specimen from Mazama sp. found in Cuvieri Cave, Lagoa Santa region, State of Minas Gerais, Brazil

Durante o Quaternário, as cavernas serviram como armadilhas naturais para numerosos grupos de animais e, devido às condições ambientais relativamente estáveis, a preservação nesse ambiente é melhor do que na superfície, de modo que o material osteológico encontrado nas cavernas representa um registro importante de eventos ambientais e mudanças na fauna. A Caverna Cuvieri faz parte do complexo Carste de Lagoa Santa, conhecido por seu grande número de cavernas contendo ossos preservados de animais recentes e extintos. Os cervídeos representam a família mais abundante de macrovertebrados encontrados na caverna de Cuvieri, com espécimes com grande variação ontogenética de representantes do gênero Mazama. O presente estudo descreve a ocorrência do espécime mais jovem deste gênero encontrado em um depósito de caverna. O espécime consiste em ossos apendiculares (fêmures, úmeros, tíbias, rádios, ulna e escápula) sem desgaste, ataque predatório ou evidência de intemperismo.

During the Quaternary, caves served as natural traps for numerous groups of animals and due to relatively stable environmental conditions preservation is better than on the surface, so the osteological material found in caves represents an important record of environmental events and faunal changes. Cuvieri Cave is part of the Lagoa Santa Karst complex, known for its large number of caves containing preserved bones of recent and extinct animals. Cervidae represent the most abundant family of macrovertebrates found at Cuvieri Cave, with specimens with large ontogenetic variation of representatives of the genus Mazama. The present study describes the occurrence of the youngest specimen of this genus found in a cave deposit. The specimen consists of appendicular bones (femurs, humerus, tibias, radios, ulna and scapula) without wear, predatory attack or evidence of weathering.

Um exemplar muito jovem de Mazama sp. encontrado na Gruta Cuvieri, região de Lagoa Santa, estado de Minas Gerais, Brasil / A very young specimen from Mazama sp. found in Cuvieri Cave, Lagoa Santa region, State of Minas Gerais, Brazil

Durante o Quaternário, as cavernas serviram como armadilhas naturais para numerosos grupos de animais e, devido às condições ambientais relativamente estáveis, a preservação nesse ambiente é melhor do que na superfície, de modo que o material osteológico encontrado nas cavernas representa um registro importante de eventos ambientais e mudanças na fauna. A Caverna Cuvieri faz parte do complexo Carste de Lagoa Santa, conhecido por seu grande número de cavernas contendo ossos preservados de animais recentes e extintos. Os cervídeos representam a família mais abundante de macrovertebrados encontrados na caverna de Cuvieri, com espécimes com grande variação ontogenética de representantes do gênero Mazama. O presente estudo descreve a ocorrência do espécime mais jovem deste gênero encontrado em um depósito de caverna. O espécime consiste em ossos apendiculares (fêmures, úmeros, tíbias, rádios, ulna e escápula) sem desgaste, ataque predatório ou evidência de intemperismo.(AU)

During the Quaternary, caves served as natural traps for numerous groups of animals and due to relatively stable environmental conditions preservation is better than on the surface, so the osteological material found in caves represents an important record of environmental events and faunal changes. Cuvieri Cave is part of the Lagoa Santa Karst complex, known for its large number of caves containing preserved bones of recent and extinct animals. Cervidae represent the most abundant family of macrovertebrates found at Cuvieri Cave, with specimens with large ontogenetic variation of representatives of the genus Mazama. The present study describes the occurrence of the youngest specimen of this genus found in a cave deposit. The specimen consists of appendicular bones (femurs, humerus, tibias, radios, ulna and scapula) without wear, predatory attack or evidence of weathering.(AU)

Comparative gender peptidomics of Bothrops atrox venoms: are there differences between them?

Bothrops atrox is known to be the pit viper responsible for most snakebites and human fatalities in the Amazon region. It can be found in a wide geographical area including northern South America, the east of Andes and the Amazon basin. Possibly, due to its wide distribution and generalist feeding, intraspecific venom variation was reported by previous proteomics studies. Sex-based and ontogenetic variations on venom compositions of Bothrops snakes were also subject of proteomic and peptidomic analysis. However, the venom peptidome of B. atrox remains unknown. Methods: We conducted a mass spectrometry-based analysis of the venom peptides of individual male and female specimens combining bottom-up and top-down approaches. Results: We identified in B. atrox a total of 105 native peptides in the mass range of 0.4 to 13.9 kDa. Quantitative analysis showed that phospholipase A2 and bradykinin potentiating peptides were the most abundant peptide families in both genders, whereas disintegrin levels were significantly increased in the venoms of females. Known peptides processed at non-canonical sites and new peptides as the Ba1a, which contains the SVMP BATXSVMPII1 catalytic site, were also revealed in this work. Conclusion: The venom peptidomes of male and female specimens of B. atrox were analyzed by mass spectrometry-based approaches in this work. The study points to differences in disintegrin levels in the venoms of females that may result in distinct pathophysiology of envenomation. Further research is required to explore the potential biological implications of this finding.(AU)

Comparative gender peptidomics of Bothrops atrox venoms: are there differences between them?

Bothrops atrox is known to be the pit viper responsible for most snakebites and human fatalities in the Amazon region. It can be found in a wide geographical area including northern South America, the east of Andes and the Amazon basin. Possibly, due to its wide distribution and generalist feeding, intraspecific venom variation was reported by previous proteomics studies. Sex-based and ontogenetic variations on venom compositions of Bothrops snakes were also subject of proteomic and peptidomic analysis. However, the venom peptidome of B. atrox remains unknown. Methods: We conducted a mass spectrometry-based analysis of the venom peptides of individual male and female specimens combining bottom-up and top-down approaches. Results: We identified in B. atrox a total of 105 native peptides in the mass range of 0.4 to 13.9 kDa. Quantitative analysis showed that phospholipase A2 and bradykinin potentiating peptides were the most abundant peptide families in both genders, whereas disintegrin levels were significantly increased in the venoms of females. Known peptides processed at non-canonical sites and new peptides as the Ba1a, which contains the SVMP BATXSVMPII1 catalytic site, were also revealed in this work. Conclusion: The venom peptidomes of male and female specimens of B. atrox were analyzed by mass spectrometry-based approaches in this work. The study points to differences in disintegrin levels in the venoms of females that may result in distinct pathophysiology of envenomation. Further research is required to explore the potential biological implications of this finding.(AU)