História natural de Ophiodes cf. fragilis (Raddi, 1820) (Squamata, Anguidae): aspectos morfológicos, reprodutivos, citogenéticos e locomotores

Abstract

Lizards from genus Ophiodes, popularly known as glass snakes, are characterized by their serpentiform body, lack of forelimbs and rudimentary hindlimbs. They have been recorded in different regions of Brazil and other countries in South America. Despite their morphological peculiarities and wide geographic distribution, studies envolving this genus are scarce. This work was developed aiming to contribute to morphological, reproductive, cytogenetic and locomotor aspects knowledges of species from the genus using several methodologies. Considering some genus taxonomic issues, we chose to name the species studied as Ophiodes cf. fragilis. The results showed no sexual dimorphism associated with shape and size in Ophiodes cf. fragilis. When the same parameters were evaluated, it was possible to differentiate this species from Ophiodes fragilis specimens. The urogenital system has a morphology similar to that previously described for Squamata. Microscopic morphological variation associated with reproductive and non-reproductive periods of the year was found. We highlight the presence of renal sexual segment in males and females adults' kidneys. The hemipenis and hemiclitors have similar microscopic structures, distinguishing themselves in shape and external morphology. The chromosomes number and morphology of Ophiodes cf. fragilis wassimilar to previous described for other species of Ophiodes. New analysis of traditional and molecular cytogenetics were performed for the first time for a species belonging to the genus. Ophiodes cf. fragilis specimens move predominantly by serpentine and rectilinear modes, with movement being observed in certain situations of vestigial posterior limb. There is a strong evidence that the posterior limb is an extremely reduced limb, not a vestigial one, due to presence of ossicles supporting it with metabolic activity and linked to a thin pelvic girdle. Osteoderms are present throughout the animal's body, with canicles morphology equivalent to that described for the genus. The present study presents unpublished data and complements other information previously known for the genus. The methodologies used and the results obtained can be easily replicated and used as a basis for future studies with other species of Ophiodes.