Deep Divergences Among Inconspicuously Colored Clades ofEpipedobatesPoison Frogs

Abstract

AbstractPoison frogs (Dendrobatidae) are famous for their aposematic species, having a combination of diverse color patterns and defensive skin toxins, yet most species in this family are inconspicuously colored and considered non-aposematic.Epipedobatesis among the youngest genus-level clades of Dendrobatidae that includes both aposematic and inconspicuous species. Using Sanger-sequenced mitochondrial and nuclear markers, we demonstrate deep genetic divergences among inconspicuous species ofEpipedobatesbut relatively shallow genetic divergences among conspicuous species. Our phylogenetic analysis includes broad geographic sampling of the inconspicuous lineages typically identified asE. boulengeriandE. espinosai, which reveals two putative new species, one in west-central Colombia (E.sp. 1) and the other in north-central Ecuador (E.aff.espinosai). We conclude thatE. darwinwallaceiis a junior subjective synonym ofE. espinosai. We also clarify the geographic distributions of inconspicuousEpipedobatesspecies including the widespreadE. boulengeri.We provide a qualitative assessment of the phenotypic diversity in each nominal species, with a focus on the color and pattern of inconspicuous species. We conclude thatEpipedobatescontains eight known valid species, six of which are inconspicuous. A relaxed molecular clock analysis suggests that the most recent common ancestor ofEpipedobatesis ∼11.1 million years old, which nearly doubles previous estimates. Last, genetic information points to a center of species diversity in the Chocó at the southwestern border of Colombia with Ecuador.