Body shape and diet reflect arboreality degree of five congeneric snakes sympatric in the Atlantic forest

• Published in: Biotropica 2022-07, Vol.54 (4), p.839-851
• Main Authors: Banci, Karina Rodrigues da Silva, Guimarães, Murilo, Siqueira, Lucas Henrique Carvalho, Muscat, Edelcio, Sazima, Ivan, Marques, Otavio Augusto Vuolo
• Format: Article
• Language: English
• Subjects: Amphibians; Animals; Body shape; Chironius; Collections; Colour; Colubridae; Density; Diet; ecology; Frogs; frog‐eating; Habitat selection; Habitat utilization; Habitats; Morphology; Snakes; Species; Substrates; Sympatric populations; Terrestrial environments; Vertebrae
• ISSN: 0006-3606; 1744-7429
• DOI: 10.1111/btp.13107

The substrate use by animals may influence both their morphology and diet. Species of the genus Chironius are among the most conspicuous frog‐eating, arboreal snakes in South America. The aim of the present study was to investigate whether diet and morphology relate to substrate use in five sympatric Chironius species from the Atlantic Forest. Our hypothesis is that habitat pressure is strong enough so that even closely related species will present differences. We collected morphological and diet data from specimens of C. bicarinatus, C. exoletus, C. foveatus, C. fuscus, and C. laevicollis housed in scientific collections. Information on habitat use were obtained by monitoring free‐ranging animals using thread‐bobbins and also from the literature. Our results demonstrate that C. foveatus is the most arboreal species, and C. laevicollis is the most terrestrial among the five studied species. Chironius foveatus is the slenderest, with one of the longest relative tail lengths, the narrowest ventral scales, the highest vertebral density, the largest eye diameter, green body color, and diet based on tree frogs (Hylidae). These traits indicate a higher arboreality for this species. On the other extreme, C. laevicollis is the stoutest species, and has the shortest tail, the largest head, the lowest vertebral density, and diet based on ground‐living frogs (Leptodactylidae). These traits indicate pronounced terrestriality for this species. The other three species have traits intermediate between the extremes showed by C. foveatus and C. laevicollis. We found evidence for a close relationship between arboreality or terrestriality, morphology, and diet. The aim of the present study is to investigate whether diet and morphology relate to substrate use in five sympatric Chironius species from the Atlantic Forest. Our hypothesis is that habitat pressure is strong enough so that even closely related species will present differences. We found evidence for a close relationship between arboreality or terrestriality, morphology, and diet in Chironius species.