Taxonomy, allometry, sexual dimorphism, and conservation of the trans-Andean water-snake Helicops danieli Amaral 1937 (Serpentes: Dipsadidae: Hydropsini).

The extensive lack of knowledge on the morphological aspects South American water-snakes, includes a poor understanding phenotypic parameters, intraspecific variation, and conservation trans-Andean Helicops species, danieli Amaral, 1937. For first time, we provide multidisciplinary view using key features (e.g., morphology niche modeling) to improve taxonomic recognition this as well describing ontogenetic color changes, allometry, sexual dimorphism, status poorly studied snake. First, emended diagnosis H. with 23 characters detected that juvenile tail length is positively related allometric growth, juveniles differ from adults through presence white nuchal collar. Females are larger than males for snout-vent length, whereas showed proportionally longer tails smaller head growth. Suitable areas restricted regions Magdalena drainage Caribbean coast, which also high values anthropic impacts. Our approach provided new insights into water snake’s morphology, distribution.