Morphology and metamorphosis ofEupsophus calcaratustadpoles (anura: Leptodactylidae)

Abstract

Eupsophus calcaratus, a leptodactyloid frog from the austral Andean forests of Argentina and Chile, has endotrophic, nidicolous tadpoles. We studied a metamorphic series from Stages 31 to 46 of Gosner's developmental table (1960). Other than the scarce pigmentation, proportionately large eyes, and massive developing hindlimbs, the remaining external characters are similar to those of generalized, exotrophic larvae. At the same time, internal morphology does not reveal any character state attributable to the endotrophic-nidicolous way of life; conversely, structures such as the hyobranchial skeleton and the mandibular cartilages are similar to those of exotrophic-macrophagous tadpoles. The metamorphic process is characterized by the delayed development of diverse structures (e.g., ethmoid region, palatoquadrate, and hyobranchial apparatus), and the retention of some larval characters (e.g., parietal fenestrae, overall absence of ossification) with the absence of development of some "juvenile" characters (e.g., adult otic process, several bones) in metamorphosed individuals. These heterochronic processes and truncation of larval development are related to a shorter larval life (when compared to other species of the austral Andean region) and to the small size at metamorphosis.

Chondrocranium, cranial muscles and buccopharyngeal morphology on tadpoles of the controversial leptodactylid frog Limnomedusa macroglossa (Anura: Leptodactylidae)

“…These characters are the presence of a long processus pseudopterygoideus (as defined by Haas, 2003), and the syndesmotic connection of the partes alares and partes corpora of the cartilago suprarostralis. Eupsophus calcaratus is the only genus of Telmatobiinae which possesses a short processus pseudopterygoideus and a cartilaginous connection between the partes corpora and the partes alares of the cartilago suprarostralis (Vera Candioti et al, 2005). This departure from the pattern of the known Telmatobiinae genera could be related to the endotrophicnidicolous development mode of this species.…”

Complementary diagnosis of the genus Insuetophrynus (Anura, Cycloramphidae) based on larval characters

“…The cartilage labiales superiores of I. acarpicus are distinguishable from those of Alsodes (Formas & Brieva 2004), Eupsophus (Vera-Candioti et al 2005);Cárdenas-Rojas et al 2007), Limnomedusa (Turner 1999) and Rhinoderma (Lavilla 1987) by having the pars alaris and pars corpora fused dorsal and ventrally.…”

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

“…Developmental times reported for some cycloramphids studied, such as the genus Eusophus, are relatively short (<90 days) (Vera Candioti et al 2005, 2011. Jorquera et al (1974) reported a complete developmental period of 75 days for Rhinoderma darwinii.…”