Phylogeny and systematics of ground rollers (Brachypteraciidae) of Madagascar

We studied relationships of five extant members of the endemic Malagasy fam ily Brachypteraciidae, the ground rollers, using several mitochondrial gene s (cytochrome-b, NADH dehydrogenase 2,12S ribosomal RNA, and cytochrome oxi dase I). As outgroups, we used other coraciiforms including the Cuckoo Roll er (Family Leptosomatidae, Leptosomus discolor), several true rollers (Corc aciidae) and a tody (Todidae). Partial sequences of the Long-tailed Ground Roller (Uratelornis chimaera) were obtained from toe pad samples taken off museum specimens. For a combined data set of all genes, Kimura two-paramete r distances between sequences of the five ground roller species were high, averaging 11% divergence. For several species, samples were available from widely separated geographic regions and intraspecific sequence divergence w as low Unweighted and weighted parsimony and maximum-likelihood analyses co nsistently recovered monophyly of the family, a sister relationship between Brachypteraciidae and Coraciidae, and monophyly of one of three currently recognized ground roller genera (Atelornis). At the base of the Brachyptera ciidae clade, we could not fully resolve relationships between Uratelornis and two species currently placed in Brachypteracias. Because of the uncerta inty of basal nodes in our phylogenetic reconstructions, we recommend retur ning B. squamigera to the monotypic genus Geobiastes. High levels of diverg ence among ground rollers are similar to levels found in other avian groups endemic to Madagascar. However, we suggest that molecular divergences appe ar far too low to be consistent with mid-Eocene fossils attributed to the f amily.