Abstract
A molecular phylogeny of the Neotropical snail-eating snakes (tribe Dipsadini Bonaparte, 1838) is presented that includes 60 of the 133 species currently recognized. There is morphological and phylogenetic support for four new species of Sibon Fitzinger, 1826 and one of Dipsas Laurenti, 1768, which are described here based on their unique combination of molecular, meristic, and color pattern characteristics. PlesiodipsasHarvey et al., 2008 is designated as a junior synonym of Dipsas and additional evidence is presented to support the transfer of the genus Geophis Wagler, 1830 to the tribe Dipsadini. Two of the subspecies of S.nebulatus (Linnaeus, 1758) are elevated to full species status. Insight into additional undescribed cryptic diversity within the S.nebulatus species complex is provided. Evidence that supports the existence of an undescribed species previously confused with D.temporalis is provided, as well as the first country record of S.ayerbeorum Vera-Pérez, 2019 in Ecuador with a comment on the ontogenetic variation of the latter. Finally, photographs of Colombian, Ecuadorian, and Panamanian snail-eating snakes are provided.