RESUMO
We studied the relationship between shape, size, and developmental time in the embryonic ontogeny of 15 species of the frog genus Physalaemus. As in other anuran exotrophic embryos, shape changes are correlated with size increase and mainly concern tail elongation, decrease in body height, and increase in fin height. Size ranges and developmental times vary interspecifically. Embryos of the P. signifer Clade and the P. gracilis Group are among the largest, are slightly peramorphic, and develop fast regarding congeneric species. Embryos of P. cicada combine the smallest sizes with fast development and the most peramorphic shapes. The paedomorphic shapes of embryos of P. biligonigerus and P. henselii groups are correlated with fast vs. slow developmental times respectively. Trajectories in the P. cuvieri Group are diverse and in general differ in size and developmental time. The embryos of P. cristinae and from the Argentinean lineage of P. cuvieri stand out with the longest development. Sequences of developmental events are overall conserved in the genus, and main differences concern mouthpart ontogeny. This study constitutes the first attempt to evaluate morphological, allometric, and heterochronic parameters of the early ontogeny of anurans and how these can vary and contribute to diversification in taxonomic groups.
Assuntos
Anuros , Animais , Anuros/anatomia & histologia , Anuros/classificação , Anuros/embriologia , Anuros/crescimento & desenvolvimento , Embrião não Mamífero/anatomia & histologia , Especificidade da Espécie , Desenvolvimento Embrionário , Fatores de TempoRESUMO
The taxonomic and biogeographic affinities of Strabomantis aramunha from the Campos Rupestres of Brazil are intriguing. A unique skull morphology of females suggest affinities with the broad-headed eleutherodactylines of Northwestern South America in the genus Strabomantis. Male and juvenile morphology nonetheless suggest S. aramunha could be related to members of the recently described genus Haddadus from eastern Brazil. We assess the affinities of S. aramunha using molecular phylogenetic analyses of mitochondrial (12S, tRNAval, 16S, cyt b) and nuclear sequences (RAG-1and rhodopsin). Bayesian inference, likelihood, and parsimony analysis recover a highly supported clade with S. aramunha and H. binotatus as sister taxa. Accordingly, we transfer S. aramunha to Haddadus, and provide a new generic definition of the later. The distribution of species in Haddadus (highlands of the Espinhaço mountain Range and coastal eastern Brazil) is now concordant with the general pattern observed for other species in the area.