Biogeographic origin and radiation of Cuban Eleutherodactylus frogs of the auriculatus species group, inferred from mitochondrial and nuclear gene sequences

We studied phylogenetic relationships of the Eleutherodactylus auriculatus species group to infer colonization and diversification patterns in this endemic radiation of terrestrial frogs of the genus Eleutherodactylus in the largest of the Greater Antilles, Cuba. An initial screening of genetic diversity based on partial sequences of the 16S rRNA gene in almost 100 individuals of all species of the group and covering the complete known geographic range of their occurrence found most species endemic to small ranges in the eastern Cuban mountains while a single species was widespread over most of Cuba. Our molecular phylogeny, based on 3731 bp of four mitochondrial and one nuclear gene, suggests that most cladogenetic events within the group occurred among clades restricted to the eastern mountains, which acted as refugia and facilitated the diversification in this group. Our results reveal two separate colonization events of Central and Western Cuba and allow inferring the timing of the subsequent diversification events that occurred between 11 and 2 Mya. Because populations previously assigned to E. auriculatus represent four genetically strongly divergent lineages that also differ in their advertisement calls, we propose that E. auriculatus as currently recognized comprises four species. The difficulties in assigning the name auriculatus to any of these four species, and the fact that E. principalis is nested within one of them, stress the need for a thorough taxonomic revision of this group.