Topographic anatomy of the cardiovascular system of the South American Rattlesnake

Abstract

Rattlesnakes (genera Crotalus and Sistrurus) are venomous serpents from the Viperidae family, encompassing over 50 species globally. They inhabit regions from the United States to Argentina, excluding Chile and Ecuador. Only one species, the South American Rattlesnake (Crotalus durissus cascavella), is found in Brazil, primarily in biomes such as the Cerrado, Caatinga, Atlantic Forest, Amazon Rainforest, and Pampa. Typically more robust than the Bothrops genus, these snakes can reach up to 160 cm in length. Most studies focus on their venom, diet, reproduction, and ecology, while knowledge on their visceral anatomy is limited. This study aims to describe the topographic anatomy of the cardiovascular system of Crotalus durissus cascavella from the Baturité Massif, Ceará, Brazil. Nine specimens (four males and five females) were examined post-mortem. The heart, located in the first third of the body, appears larger in females. The cardiovascular system includes the heart and its vessels, such as the anterior and posterior venae cavae, coronary veins, and pulmonary veins. The heart consists of three chambers: two atria and one partially divided ventricle. This research provides critical insights into the cardiovascular anatomy of the South American Rattlesnake, enhancing our understanding of this species.