Morfologia oral interna e condrocrânio do girino de Rhinella Casconi Roberto, Brito & Thomé, 2014 (ANURA: BUFONIDAE)

Abstract

Studies focused on larval morphology in anuran amphibians have proven fundamental for understanding evolutionary and ecological aspects among groups. The chondrocranium in tadpoles presents a large set of informative characters related to functional adaptations and structural variations of the cranial cartilage. This study describes the internal oral anatomy and chondrocranium of the tadpole of R. casconi, a species found exclusively in the Serra de Baturité, in the state of Ceará, Northeast Brazil. The species is restricted to altitudes above 700 m, in high-altitude marshy areas, with records in the municipality of Guaramiranga. Four individuals were analyzed for chondrocranium and hyobranchial apparatus, and two individuals for internal oral morphology between stages 35 and 36. Overall, the tadpole of R. casconi presented characteristics similar to other tadpoles of the genus Rhinella with such described structures, such as the presence of a single pair of infralabial papillae, a generally longer chondrocranium than it is wide, short trabecular processes on the lateralis, and a long quadratoethmoidal process. However, some data show important differences in relation to other Rhinella, such as the absence of papillae in the post-choanal arena, the addition of a lingual papilla, the presence of a discreet nasal septum, and the prootic foramen.