Hidden diversity within the depauperate genera of the snake tribe Lampropeltini (Serpentes, Colubridae).

•Identified undocumented diversity in Lampropeltinine genera via increased sampling.•First molecular evidence for monophyly and phylogenetic placement of two putative species.•Cochise Filter Barrier acts as a clear biogeographic break for Arizona and Rhinocheilus.•Incongruence among Lampropeltini topologies likely due to rapid speciation rate.•Increased sampling in coalescent framework yielded same topology as NGS dataset.