Published online by Cambridge University Press: 28 February 2007
On the island of Madagascar and five neighbouring islands: Aldabra, the Comoros, Mauritius, Réunion and the Seychelles, the number of hitherto found Ptyctima species is 57, including 37 Phthiracaroidea (of which ten are new to science), 18 Euphthiracaroidea (one new to science) and two Mesoplophoroidea. Of those 57 species, 30 are endemic (53%), ten Ethiopian species (17%), 12 pantropical species (21%) three oriental (5%) and two semicosmopolitan (3%). Endemism of Phthiracaroidea (62%) is similar to Euphthiracaroidea (59%). Similarity between the ptyctimous fauna of Madagascar and the neighbouring islands is very small—only one or two species are common. Moreover, the fauna of Mauritius is completely different from that of Madagascar. The ptyctimous fauna of Madagascar and the near islands must have been shaped before separation of Madagascar from Africa, which is suggested by the presence of the phylogenetically oldest and the youngest genera of Phthiracaroidea and Euphthiracaroidea. On the other hand, a large number of species of late derived genera Notophthiracarus and Hoplophorella may indicate a relatively late colonization of the islands by Phthiracaroidea. Dispersion of Ptyctima onto Madagascar and the neighbouring islands took place from the east—the Oriental region or from the south—the Australian region.