Eye ontogeny in Pleurodema bufoninum: a comparison with Pleurodema somuncurense (Anura, Leptodactylidae)

VOLONTERI, M. C.; BARRASSO, D. A.; COTICHELLI, L.; BASSO, N. G.; HERMIDA, G. N.

JOURNAL OF MORPHOLOGY

WILEY-LISS, DIV JOHN WILEY & SONS INC

Lugar: New York; Año: 2017 vol. 278 p. 896 - 906

0362-2525

Vision is one of the main sensory systems in amphibians, and the eye structure is highly associated 8 with habitat conditions. The ontogeny, as well as the adult structure, of the eye has been studied 9 in only a few species. The life change after metamorphosis is accompanied by changes in the visual 10 environment. The aim of this work is to describe the eye ontogeny of Pleurodema bufoninum and 11 to compare it with that of Pleurodema somuncurense. Specimens of both Pleurodema species were 12 processed for histology analysis at different stages of development, including the tadpole, postme- 13 tamorphic, and adult forms. Eyes in both Pleurodema species are composed of the 3tunics, tunica fibrosa, tunica vasculosa, and tunica interna, and the lens. Additionally, in both, the iris presents a 15 projection on its dorsal and ventral free ends that screens the cornea. This structure has been 16 reported in the eye of several anuran species and is called the umbraculum, meniscus or pupillary 17 nodule. Our results show that the structures related to light capture (retina and lens) appear early 18 in larval life, while the components of the terrestrial-life eye (scleral cartilage, specialized cornea, 19 eyelids, nictitating membrane, and Harderian?s gland) do not develop until the metamorphic climax, 20 when the tadpole leaves the water. The adult eyes of P. bufoninum and P. somuncurense are very similar in structure and development.