A new species of Hemidactylus (Squamata: Gekkonidae) from Principe Island, Gulf of Guinea, West Africa with comments on the African-Atlantic clade of Hemidactylus geckos

The remote oceanic Gulf of Guinea islands of Sao Tome and Principe are home to a highly endemic herpetofauna, which has become the focus of modern, on-going scientific analysis only during the past decade. Until now, the endemic Hemidactylus greeffi Bocage 1886 (Greeff's giant gecko) has been considered to occur on both islands. Herein, we employ both new and previously published molecular data, along with differences in morphological characters, to demonstrate that the Principe populations are a full species distinct from H. greeffi. We describe the new species and restrict the range of H. greeffi to the island of Sao Tome. The original unnumbered holotype of H. greeffii held in the Museu Bocage was destroyed in Lisbon and we have been unable to determine the collection provenance of unnumbered material treated by subsequent authors. We therefore designate a neotype for H. greeffi from California Academy of Science collections and provide morphological information on that species additional to that of earlier workers, based upon 14 specimens collected in various localities on Sao Tome during the past decade.