Microspizias Sangster et al., 2021 (new genus)
(An individual of Microspizias superciliosus, photographed by Aitor, under CC BY 4.0)
Meaning of name: Microspizias = small hawk
Species included: M. superciliosus (tiny hawk, type species, previously in Accipiter) and M. collaris (semicollared hawk, previously in Accipiter)
Age: Holocene (Meghalayan), extant
Where found: Forests of Central and South America
Notes: Microspizias is a genus of small (thrush-sized) hawks. Fairly little is known about the biology of the two living species, but they appear to prey mostly on other birds. They were formerly classified in the genus Accipiter, which includes a diverse assemblage of other forest-dwelling, bird-hunting hawks, such as the Eurasian sparrowhawk (A. nisus) and the sharp-shinned hawk (A. striatus). However, recent phylogenetic studies have found that the tiny hawk and semicollared hawk are not closely related to members of the genus Accipiter, instead being more closely related to the lizard buzzard (Kaupifalco monogrammicus).
Although some researchers have suggested that the old genus Hieraspiza could be brought back for the tiny hawk and the semicollared hawk on the basis that Gray (1955) designated the tiny hawk as its type species, the authors of a new paper argue that this designation is untenable because the first valid usage of the name Hieraspiza did not include the tiny hawk as a member of this genus. They thus coin the new genus Microspizias for these two species.
Reference: Sangster, G., G.M. Kirwan, J. Fuchs, E.C. Dickinson, A. Elliott, and S.M.S. Gregory. 2021. A new genus for the tiny hawk Accipiter superciliosus and semicollared hawk A. collaris (Aves: Accipitridae), with comments on the generic name for the crested goshawk A. trivirgatus and Sulawesi goshawk A. griseiceps. Vertebrate Zoology 71: 419–424. doi: 10.3897/vz.71.e67501