Homopholis and blaesodactylus (Squamata: Gekkonidae) revisited: New insights from a molecular phylogeny

Abstract

South African Homopholis Boulenger, 1885 and Madagascan Blaesodactylus Boettger, 1893 are gekkonid genera originally distinguished by minor differences in scalation. Subsequent morphological studies have argued either for synonymy of the genera, or retention of the original 19th century taxonomy. Moreover, the validity and boundaries of putative species within each genus, as well as the relationships of each genus to other gekkonid genera, remains unresolved and contentious. We sequenced 3433 aligned bp of mitochondrial (ND2 and ND4) and nuclear (RAG‐1 and PDC) DNA sequence data from 14 samples of Homopholis and Blaesodactylus representing all six recognized species in these two genera, and based on a larger, unpublished study of all gekkotan relationships, eight samples of Geckolepis and two species of Afroedura for outgroups. Results indicated a strongly supported, mono‐phyletic clade including Geckolepis as the sister group to Blaesodactylus + Homopholis, with the latter two genera reciprocally monophyletic. Given the clear morphological and biogeographic distinctness of Homopholis sensu stricto from Blaesodactylus, as well as deep genetic divergence between the two groups, we favor the retention of Blaesodactylus as the valid generic name for the Madagascan species. Homopholis mulleri is confirmed as a valid species, and evidence of cryptic speciation is suggested among divergent samples of H. walbergii (often misspelled in the literature), and among samples of Blaesodactylus and Geckolepis. The pattern observed among South African samples of H. walbergii suggests an important role for the Soutpansberg as a barrier to gene flow.