External changes in embryonic and larval development of Odontophrynus cordobae Martino et Sinsch, 2002 (Anura: Cycloramphidae)

GRENAT, P. R., ZAVALA GALLO, L. M., SALAS, N.E. & MARTINO, A. L.

BIOLOGIA

VERSITA

Lugar: Varsovia; Año: 2011 vol. 66 p. 1148 - 1158

0006-3088

We provide the first description of development for a species belonging to Odontophrynus genus by describing all external changes of embryonic and larval stages for Odontophrynus cordobae. External morphological changes through development were analyzed on specimens bred in captivity. Embryonic and larval development, from fertilization to metamorphosis, was completed in 62 days and 46 stages were defined. We split the staging series into ten developmental groups: fertilization (stages 1 and 2); segmentation (stages 3?9); gastrulation (stages 10?12); neurulation (stages 13?16); elongation (stages 17?19); external gill larva (stages 20?24); internal gill larva (stage 25); pre?metamorphosis (stages 26?41); pro?metamorphosis (stage 42); metamorphic climax (stages 43?46). Marked increases in total length were evidenced during elongation and during stage 25, when the tadpole begins to feed. Stage 25 was the longest one (8 days) and it was related to organs rearrangement, morphological progression and body mass increment typical of free life larval form. Similar studies on related species are needed to compare different developmental stages at different taxonomic levels.