First record of melanism in Tomodon dorsatus (Duméril, Bibron & Duméril, 1854) (Serpentes: Dipsadidae: Tachymenini)
Keywords:
Snakes, Phenotypic Variation, Scientific Collection, PigmentationAbstract
Melanism, characterized by the excessive production of dark pigments, is a well-documented phenomenon in snakes, although its ecological and evolutionary causes remain poorly understood in Neotropical species. During curatorial work in the Herpetological Collection of the Universidade Federal de Juiz de Fora - Reptiles (CHUFJF), three melanistic specimens of Tomodon dorsatus collected between 2007 and 2009 in the municipality of Cristina, Minas Gerais, Brazil, were recorded. The specimens, all adult males, exhibited predominantly black body coloration with small whitish ventral areas. The presence of multiple records from the same locality suggests that melanism may be a recurrent and geographically restricted phenotype within this population. These data expand current knowledge of chromatic variation in the species and highlight the importance of population, ecological, and genetic studies to better understand the mechanisms and frequency of melanism in this group.
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