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bioRxiv · 10.1101/2020.10.02.324459

Differences in external, internal oral and chondrocranial morphology of the tadpole of Corythomantis greeningi Boulenger, 1896 (Anura: Hylidae)

Uchoa, L. R.·Costa, C. A.·Santos, A. J. S.·Silva, R. A.·Sena, F. P.·Andrade, E. B.
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Abstract

The genus Corythomantis currently comprises a single species, Corythomantis greeningi, a hylid widely distributed in xerophilic and subhumid morphoclimatic regions of Brazil, mainly in the Northeast region. Recently the external morphology, internal oral anatomy, and chondrocranium of C. greeningi tadpoles were described from specimens collected in the state of Bahia, however, we observed some differences in morphology of individuals from the state of Piaui, northeastern Brazil. The tadpoles were collected during the 2019 rainy season and 14 individuals were used to describe and compare the larval characters. We observed differences in external, internal oral and chondrocranial morphology in relation to specimens previously described, especially in oral disc, number and shape of oral cavity papillae, and some chondrocranium structures, as: cartilago suprarostralis, cornua trabeculae, fontanella frontoparietalis, cartilago orbitalis e planum hypobranchiale. Our results point to the occurrence of heterochrony in C. greeningi, but we do not rule out the possibility that tadpoles belong to different species. Further studies involving a greater number of tadpoles at different stages, combined with genetic, acoustic, and morphological factors of adult specimens may establish the variation degree of C. greeningi in different regions of northeastern Brazil. RESUMOO genero Corythomantis compreende atualmente uma unica especie, Corythomantis greeningi, um hilideo amplamente distribuido nas regioes morfoclimaticas xerofilicas e subumidas do Brasil, principalmente na regiao Nordeste. Recentimente foram descritas a morfologia externa, anatomia oral interna e condrocranio do girino de C. greeningi a partir de especimes coletados no estado da Bahia, no entanto, observamos algumas diferencas na morfologia dos individuos coletados na regiao norte do estado do Piaui, Nordeste do Brasil. Os girinos foram coletados durante o periodo chuvoso de 2019 e 14 individuos foram utilizados para descricao e comparacao dos caracteres larvais. Observamos diferencas na morfologia externa, oral interna e no condrocranio do girino em relacao ao descrito anteriormente, sobretudo no disco oral, no numero e formato de papilas cavidade oral e algumas estruturas do condrocranio, como: cartilago suprarostralis, cornua trabeculae, fontanella frontoparietalis, cartilago orbitalis e planum hypobranchiale. Nossos resultados apontam a ocorrencia de heterocronia em C. greeningi, porem nao descartamos a possibilidade dos girinos pertencerem a especies diferentes. Estudos futuros envolvendo uma maior area de distribuicao e maior numero de individuos em estagios diferentes, aliados a fatores geneticos, acustico e morfologicos dos especimes adultos poderao estabelecer o grau de variacao de C. greeningi em diferentes regioes do Nordeste brasileiro.

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Uchoa, L. R., Costa, C. A., Santos, A. J. S., Silva, R. A., Sena, F. P., Andrade, E. B.. 2020-10-04. Differences in external, internal oral and chondrocranial morphology of the tadpole of Corythomantis greeningi Boulenger, 1896 (Anura: Hylidae). https://doi.org/10.1101/2020.10.02.324459

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