HISTOLOGY OF THE OVARY AND OVIDUCT OF THE DIRECT DEVELOPING FROG Oreobates discoidalis (ANURA: STRABOMANTIDAE)

Abstract

Oreobates discoidalis is an anuran that reproduces in moist and sheltered habitats, laying relatively large eggs directly on land, and undergoing direct development. In this study, we describe the histology of the sexual organs of mature females during the reproductive period. Our observations reveal ovaries consisting of a single lobe, type 3 ovarian follicles exhibiting sectorization of the cytoplasm due to the accumulation of vitelline platelets, with some of these follicles exhibiting cubic epithelium, and theca formed by two layers in type 3 and 4 ovarian follicles. The oviduct is dominated by acid-type glycoconjugates exhibiting a labyrinthine distribution, organized in a fibrillar and granular manner. This study has revealed distinctive features in the architecture of glucid compounds and the monitoring of oviductal compounds in females of O. discoidalis. These characteristics would be suitable for a water-independent mode of reproduction.