Comparative skin histology of neotropical odontophrynid frogs

O'DONOHOE, M.E. AILÍN; HADDAD, CÉLIO F.B.; REGUEIRA, ELEONORA; HERMIDA, GLADYS N.; ROSSET, SERGIO D.; BASSO, NÉSTOR G.

ZOOLOGISCHER ANZEIGER

ELSEVIER GMBH

Año: 2022 vol. 301 p. 127 - 144

0044-5231

Amphibian skin is a complex organ with dermal glands which, according to their morphology, are classified asacinar and alveolar (both usually known as mucous glands) and syncytial (usually known as serous, granular orpoison glands). The latter may be scattered or grouped forming protuberances known as warts or macroglands,which are histologically distinguished. Particularly, skin protuberances in the family Odontophrynidae havebeen used as diagnostic characters; however, scarce works describe them in detail. For this reason, we studied thehistomorphology and histochemical properties of the skin in the postorbital-supratympanic and dorsal regions inspecies of the three genera composing this family. Our results showed that Odontophrynidae has peculiarcharacteristics such as the presence of neutral glycoconjugates in the secretion of the syncytial glands. Similaritieswere mostly observed between the sister taxa Odontophrynus and Macrogenioglottus with respect to thepresence of blunt spine-like projections, large syncytial glands with stoma-like pores, and the morphology andhistochemistry of the secretion in the large syncytial glands. The described histomorphological characteristics donot support the recognition of phenetic groups; however, they contribute to the identification at the species level,particularly differentiating cryptic species. Regarding differences between the three genera, the protuberances ofthe postorbital-supratympanic region in species of Odontophrynus, excepting Odontophrynus reigi, can be recognizedas macroglands, while in Proceratophrys they are observed as warts. In Macrogenioglottus alipioi protuberancesshow intermediate traits between warts and macroglands.