Parasitic helminths in Boana pulchella (Duméril & Bibron, 1841) (Anura: Hylidae) and their relation with host diet, body size, and habitat

We analyzed the diet and helminthological fauna of the frog Boana pulchella from the extreme south of Brazil. A total of 100 males were collected from two wetland areas in the state of Rio Grande do Sul: Ilha dos Marinheiros (n = 50) in the Rio Grande municipality, and the UFPel/ Embrapa (n = 50) in the Capão do Leão municipality. Boana pulchella food items and helminths found in different organs were identified and quantified. We analyzed the relationship between helminth assemblage and host diet, body size, and sampling sites. Boana pulchella presented a generalist diet, composed mainly of terrestrial insects, with diet richness higher at Ilha dos Marinheiros. Helminth fauna was composed of Nematoda, Cestoda, Digenea, and Acanthocephala, with no difference in helminth richness and abundance between sampling sites. However, the abundance of helminths presented a significant correlation with the volume of items found in the gastrointestinal contents of the anurans from UFPel/Embrapa-CL. Although for some helminth taxa there were significant differences in prevalence and mean intensity of infection among host size classes, the GLM (generalized linear model) between helminth abundance and anuran SVL (snout-vent length) was not significant. Oxyascaris oxyascaris, Cosmocercinae gen. spp., Ochoterenella sp., Diplostomidae gen. spp., Pseudoacanthocephalus sp., and Centrorhynchus sp. were the main taxa constituting the helminth assemblage associated to B. pulchella males at the sampling sites. The occurrence of helminths at larval and adult stages suggests that B. pulchella may occupy different trophic levels in the biological cycles of those helminths. This helminth parasitic fauna associated with B. pulchella is mainly composed of taxa with heteroxenous cycles involving several intermediate and paratenic hosts, which agrees with the observations of a typical generalist anuran diet in this species.Asociación Herpetológica Argentin

The activity patterns and microhabitat use of Pseudis minuta Günther, 1858 (Anura, Hylidae) in the Lagoa do Peixe National Park, a biosphere reserve of the brazilian subtropics

Pseudis minuta is abundant in a variety of aquatic environments of the Pampa domain. Therefore, it can be considered a good model for testing hypotheses on environmental heterogeneity and the influence of climate on the activity of anurans. In this study, we examined the spatial distribution pattern of P. minuta in terms of microhabitats and the influence of abiotic factors on seasonal fluctuations in the abundance of this species. Samples were collected monthly from April 2008 to May 2009 in wetlands and coastal dunes in the Lagoa do Peixe National Park. A total of 112 specimens of P. minuta were collected, of which 45 were found in the wetland area and 67 in the dune area. The species showed seasonal fluctuation in abundance, and it was most abundant in months with higher temperatures (spring-summer). Pseudis minuta was mainly associated with aquatic vegetation, an expected pattern in terms of their morphological adaptations to this environment. Among the abiotic parameters analyzed, only the monthly mean temperature showed a significant correlation (p < 0.05; r = 0.67) with the abundance of P. minuta. We concluded that P. minuta is a generalist species with respect to microhabitat use and also that fluctuation in its population abundance is mainly associated with seasonal variation in temperature

The activity patterns and microhabitat use of Pseudis minuta Günther, 1858 (Anura, Hylidae) in the Lagoa do Peixe National Park, a biosphere reserve of the brazilian subtropics

Pseudis minuta is abundant in a variety of aquatic environments of the Pampa domain. Therefore, it can be considered a good model for testing hypotheses on environmental heterogeneity and the influence of climate on the activity of anurans. In this study, we examined the spatial distribution pattern of P. minuta in terms of microhabitats and the influence of abiotic factors on seasonal fluctuations in the abundance of this species. Samples were collected monthly from April 2008 to May 2009 in wetlands and coastal dunes in the Lagoa do Peixe National Park. A total of 112 specimens of P. minuta were collected, of which 45 were found in the wetland area and 67 in the dune area. The species showed seasonal fluctuation in abundance, and it was most abundant in months with higher temperatures (spring-summer). Pseudis minuta was mainly associated with aquatic vegetation, an expected pattern in terms of their morphological adaptations to this environment. Among the abiotic parameters analyzed, only the monthly mean temperature showed a significant correlation (p < 0.05; r = 0.67) with the abundance of P. minuta. We concluded that P. minuta is a generalist species with respect to microhabitat use and also that fluctuation in its population abundance is mainly associated with seasonal variation in temperature.Pseudis minuta é uma espécie abundante em diferentes tipos de ambientes aquáticos do domínio Pampa. Por essa razão, essa espécie pode ser considerada um bom modelo para testar hipóteses relacionadas à heterogeneidade ambiental e à influência do clima sobre padrões de atividade em anuros. Neste trabalho, foi avaliado o padrão de distribuição espacial de P. minuta em termos de micro-habitats, além de se avaliar a influência de fatores abióticos nas flutuações sazonais da abundância dessa espécie. Coletas foram realizadas mensalmente, entre abril de 2008 e maio de 2009, em áreas úmidas e de cordões de dunas costeiras no Parque Nacional de Lagoa do Peixe. Um total de 112 indivíduos de P. minuta foi coletado, sendo 45 em áreas de banhado e 67 em área de dunas. A espécie apresentou flutuação sazonal na abundância, sendo mais abundantes em meses com temperaturas mais elevadas (primavera-verão). Pseudis minuta esteve associada principalmente à vegetação aquática, um padrão esperado em função de suas adaptações morfológicas a esse meio. Entre os parâmetros abióticos analisados, somente a temperatura média mensal apresentou correlação significativa (p < 0.05; r = 0,67) com a abundância de P. minuta. Foi possível concluir que P. minuta é uma espécie generalista com relação ao uso do habitat e que as flutuações na sua abundância populacional estão principalmente associadas à variação sazonal da temperatura