Topographic anatomy and sexual dimorphism of Bothrops erythromelas AMARAL, 1923 (Squamata: Serpentes: Viperidae)

Abstract

information on the internal anatomy of brazilian serpents is scarce. Bothrops erythromelas AMArAl, 1923, native to the northeast brazilian ecoregion called Caatinga, is also poorly known with regard to its biology. this study aimed to investigate the topographic anatomy and sexual dimorphism in B. erythromelas. the position of internal organs was characterized by the numbers of the ventral scales where they began and ended. to check for potential sexual dimorphism, the number of ventral scales, snout-vent length, tail length, head length, head width, head height and head volume was assessed. the topographic situation of the heart follows the pattern found in the family Viperidae, in which this organ is in a comparatively caudal position. the presence of tracheal lungs, a distinctive feature of this group was verified. differences in snout-vent length were near significant, with higher values for females, probably to provide space and nutritional resources for large litter. Also, the values in height and volume of the head were higher for females.