Diversity of reptiles in the Comores islands - stepping stones from Madagascar to Mozambique.

Funder

Organizational Unit

Publications

Phylogenetic relationships of African green snakes (genera Philothamnus and Hapsidophrys) from São Tomé, Príncipe and Annobon islands based on mtDNA sequences, and comments on their colonization and taxonomy

Publication . Jesus, José; Nágy, Zoltan T.; Branch, William R.; Wink, Michael; Brehm, António; Harris, D. James

Mitochondrial sequences (16S rRNA and cytochrome b) of the colubrine snake genera Philothamnus and Hapsidophrys were analysed. Samples were obtained from three volcanic islands in the Gulf of Guinea. The main objective was to infer phylogenetic relationships between the taxa and to trace back the colonization patterns of the group. Both insular species, Philothamnus girardi and Philothamnus thomensis, form a monophyletic unit indicating a single colonization event of one island (probably São Tomé) followed by dispersal to Annobon. Genetic divergence was found to be relatively low when compared with other Philothamnus species from the African mainland, but sufficient to consider the two taxa as distinct sister species. Here we also present evidence on the distinct phylogenetic position of Hapsidophrys sp. from the island of Príncipe, which should be considered as a distinct species, Hapsidophrys principis, a sister taxon of H. smaragdina.

2009Journal article

Open access

Phylogenetic relationships of Lygodactylus geckos from the Gulf of Guinea islands: rapid rates of mitochondrial DNA sequence evolution?

Publication . Jesus, José; Brehm, António; Harris, D. James

Mitochondrial DNA (12S rRNA, 16S rRNA and cytochrome b) sequences and nuclear sequences (C-mos) were analysed within Lygodactylus thomensis from three volcanic islands in the Gulf of Guinea that have never been connected to the continent. Our aim was to assess interrelationships between the three subspecies to test a recent hypothesis suggesting high rates of mitochondrial DNA (mtDNA) sequence evolution in geckos. Our results indicate, based on mtDNA sequence data, that the three subspecies are genetically differentiated at a level more typically observed between species. However, the forms cannot be differentiated using the nuclear marker C-mos. These results further substantiate the hypothesis of rapid rates of mtDNA sequence evolution in geckos, although the alternative that C-mos is evolving more slowly cannot be discounted. They also suggest that present calibrations for molecular clocks are at the upper limit of divergence over time.

2006Journal article

Open access