Topographic anatomy of the digestive system of the South American Rattlesnake
Keywords:
Gastrointestinal morphology, snake, ViperidaeAbstract
Rattlesnakes (genera Crotalus and Sistrurus), belonging to the Viperidae family, are venomous snakes endemic to the Americas, with over 50 species ranging from the United States to Argentina. In Brazil, only Crotalus durissus is found, except in parts of the Atlantic Forest and Amazon. This species is divided into five subspecies, with C. d. cascavella inhabiting the Caatinga biome. Rattlesnakes are medium-sized and are characterized by brown coloration with diamond-shaped dorsal spots and parallel light lines running from the neck to mid-body. A distinctive feature is their rattle, composed of keratin segments that produce a characteristic sound when shaken for defense. Research on rattlesnakes focuses on their venom, but studies also cover diet, reproduction, and ecology, predominantly in southern and southeastern Brazil. Anatomical studies, especially on the soft tissues and topography, are scarce. This study describes the topographic anatomy of the digestive system of nine C. d. cascavella individuals from Baturité, Ceará, Brazil. The digestive system includes the mouth, esophagus, stomach, intestines, and cloaca. Key findings highlight the elastic esophagus and the highly folded stomach walls. This study enhances the understanding of the South American rattlesnake's internal anatomy and digestive system, suggesting anatomical conservation among Viperidae species.
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