The California Academy of Sciences Gulf of Guinea expeditions (2001,2006) VI. A new species of Phrynobatrachus from the Gulf of Guinea islands and a reanalysis of Phrynobatrachus dispar and P. feae (Anura: Phrynobatrachidae)

The oceanic islands of Sao Tome and Principe in the Gulf of Guinea of Africa harbor a surprising number of endemic amphibians. Two species of puddle frogs (Phrynobatrachus) have been described from these islands: Phryaobatrachus dispar (Peters, 1870) and P. feae (Boulenger, 1906). The validity of P. feae as a taxon distinct from P. dispar has been in doubt and in recent works the two have been considered synonymous. However, a detailed analysis has never been performed. We examined 175 specimens of Phrynobatrachus collected from the two islands during the 2001 and 2006 CAS Gulf of Guinea expeditions as well as two syntypes of P. feae. Consistent external morphological and osteological differences were found between specimens from different islands. Furthermore, maximum likelihood analysis of cytochrome b sequences revealed a high mean inter-island sequence divergence of 21%, whereas intra-island distances were only around 1%. This level of divergence indicates an ancient split, possibly predating the formation of Sao Tome. Mitochondrial DNA sequences from 12S rRNA, valine-tRNA, and 16S rRNA genes support this divergence and indicate that the P. dispar clade is sister to an East African clade of Phryuobatrachus, and not West African species, a recurrent theme with this insular amphibian fauna. Because the type localities of both currently available names are on Principe Island, the species endemic to Sao Tome is undescribed. We thus describe a new species of Phrynobatrachus, raising the current total of endemic amphibian species in the Gulf of Guinea Islands from six to seven.