Mohoidae

Taxonomy

Until recently, these birds were thought to belong to the family Meliphagidae (honeyeaters) due to their very similar appearance and behavior, including many morphological details. However, a 2008 study argued, on the basis of a phylogenetic analysis of DNA from museum specimens, that the genera Moho and Chaetoptila are not even closely related to the Meliphagidae but instead belonged to a group within the Passerida that includes the waxwings and the palmchat; they appeared especially close to the silky-flycatchers. Hawaiian honeyeaters did not evolve from the similar looking Australasian honeyeaters, but instead represented a striking case of convergent evolution. The authors proposed a family, Mohoidae, for these two extinct genera.

Phylogenetic evidence from a 2019 taxonomic study supports the Mohoidae having an early Miocene origin, having originated 15-20 million years ago, and being the sister group to the family Hypocoliidae, which contains only the grey hypocolius (Hypocolius ampelinus), with the clade containing Mohoidae and Hypocoliidae being sister to the hylocitrea of Hylocitreidae, which diverged from them slightly earlier in the Miocene. This makes them much older than the other major radiation of endemic Hawaiian birds, the Hawaiian honeycreepers (a clade within Fringillidae), which originated much later in the Miocene, around 7 million years ago.