A 2006 study of the nuclear DNA of the pittas was the first to examine most representatives of the family, and found evidence of three major clades of pitta. Based on the study the pittas were split into three genera. The first clade, using the genus name Erythropitta, included six species that had previously been considered closely related based on external features. They are all generally small species with small tails, extensive amounts of crimson or red on the underparts, and greenish or blueish backs. The second genus, Hydrornis, includes variable Asian species. These species are unified morphologically in exhibiting sexual dimorphism in their plumage, as well as in possessing cryptic juvenile plumage (in all the species thus-far studied). This genus includes the eared pitta, which had often been placed into its own genus, Anthocincla, on account of its apparently primitive characteristics. The third genus, Pitta, is the most widespread. Most species in this genus have green upperparts with a blue wing-patch, dark upperparts and cinnamon-buff underparts. This clade contains all the migratory pitta species, and it is thought that many of the pitta species from islands are derived from migratory species. This division of the pittas into three genera has been adopted by the International Ornithological Congress' (IOC) Birds of the World: Recommended English Names, the Handbook of the Birds of the World's HBW Alive checklist, and the International Union for Conservation of Nature (which follows the HBW Alive checklist).
