Day geckos (Phelsuma) in northern Madagascar: first step to resolve a paradoxical case of mitochondrial paraphyly and morphological differentiation.

We describe a new subspecies of day gecko, Phelsuma dorsivittata paradoxa ssp. n. (Squamata: Gekkonidae) from Nosy Be Island and the Sambirano region in northwestern Madagascar. Due to its colouration and small size, Phelsuma d. paradoxa shares at first glance more similarities with P. parva or P. quadriocellata than with P. d. dorsivittata. Yet, phylogenetic analysis of mitochondrial and nuclear-encoded DNA sequences unambiguously shows that P. d. paradoxa is related to the allopatrically distributed P. d. dorsivittata. Due to the substantial and constant morphological divergence and the geographic separation between the two taxa we concluded that assigning them an initial status of subspecies is adequate, although they are not reciprocally monophyletic in mitochondrial DNA. Subsequently we discuss possible scenarios for eyespot convergence and mitochondrial paraphyly within P. dorsivittata. Furthermore, the molecular data presented here confirm the separate position of P. lineata punctulata within the P. dorsivittata complex. In order to resolve the paraphyly of the Phelsuma lineata complex, we here elevate this taxon to species rank, as Phelsuma punctulata Mertens, 1970. [ABSTRACT FROM AUTHOR]