Molecular phylogeny of Chloropseidae and Irenidae - cryptic species and biogeography.

Chloropseidae (Leafbirds) and Irenidae (Fairy-bluebirds) are colourful Oriental birds, which have been placed as a deep (old) branch in the radiation of passeroid songbirds. We present a densely sampled molecular phylogeny of the two families based on two nuclear introns (GAPDH and ODC) and two mitochondrial genes (ND3 and cyt-b) largely stemming from old museum specimens. Our results show that several subspecies within both Chloropseidae and Irenidae are genetically distinct and separated in the Miocene some 10-11Million years ago (Mya), indicating a substantial underestimation of species numbers within the two families. Based on our molecular findings, plumage distinctiveness and contemporary distributions we propose that several subspecies be recognised at the species level. Furthermore, we use the molecular data to examine biogeographical patterns of the two families in the light of historical geological re-arrangements in the region. The results indicate that the Philippines were colonised in the Pliocene and that colonisation probably progressed via the Sulu islands from Borneo and not via Palawan, which was first colonised in the Pleistocene.