Accipiter

Accipiter is a genus of birds of prey within the family Accipitridae. While some of its members are known as sparrowhawks, that common name also applies to species in other genera, such as *Tachyspiza*. The word *Accipiter* comes from Latin for "hawk," derived from *accipere*, meaning "to grasp."

These raptors are slender, with short, broad, rounded wings and a long tail that aids maneuverability in flight. They have long legs and long, sharp talons for killing prey, along with a sharp, hooked bill for feeding. Females are generally larger than males. Their hunting style involves ambushing small birds and mammals, capturing them after a brief chase. Their typical flight pattern consists of a series of flaps followed by a short glide. They are most often found in wooded or shrubby habitats.

The genus was introduced by French zoologist Mathurin Jacques Brisson in 1760, with the Eurasian sparrowhawk (*Accipiter nisus*) as the type species.

A notable skeletal feature in many birds of prey is the procoracoid foramen—a hole in the front process of the coracoid bone that houses the supracoracoideus nerve. In some birds this appears as a notch (incisura), which may be partially closed by bone, or it may be entirely absent. In most *Accipiter* hawks studied, the foramen is absent, a trait proposed as a diagnostic feature. Studies of accipitrid skeletons found procoracoid incisurae (rather than foramina) in the eagles *Aquila gurneyi* and *A. chrysaetos*, but not in four other *Aquila* species. The notch was variably open or weakly ossified in *Spizastur melanoleucos*, *Lophoaetus occipitalis*, *Spizaetus ornatus*, and *Stephanoaetus coronatus*. Among buteonine hawks, *Buteo brachyurus* and *B. hemilasius* had incisurae, unlike 17 other *Buteo* species. In *Circus*, the foramen was variable, even between sides of the same individual, usually open or absent but sometimes closed by a thin thread of bone. Genetic research later showed *Circus* is closely related to *Accipiter*. The notch was absent or indistinct in *Harpagus bidentatus*. *Urotriorchis macrourus* has a well-developed procoracoid foramen, suggesting it is separate from *Accipiter* and possibly related to the chanting goshawks of the tribe Melieraxini.

Taxonomically, the genus *Accipiter* once contained about 50 species. Molecular phylogenetic studies revealed this arrangement was non-monophyletic. A densely sampled 2024 study of the Accipitridae redefined generic boundaries to create monophyletic groups. Species were moved from *Accipiter* into five new or resurrected genera, leaving only nine species in *Accipiter*. The southeast Asian crested goshawk and Sulawesi goshawk, found to be only distantly related to other *Accipiter* species, were moved to the resurrected genus *Lophospiza*, the sole genus in the new subfamily Lophospizinae. The very small South American tiny hawk and semicollared hawk were moved to the newly erected genus *Microspizias*, placed with *Harpagus* in the subfamily Harpaginae. The genera *Circus*, *Megatriorchis*, and *Erythrotriorchis* were found to be nested within *Accipiter*. Rather than absorbing these genera into an expanded *Accipiter*, species were moved from *Accipiter* to the resurrected genera *Aerospiza*, *Tachyspiza*, and *Astur*.

Currently, the genus *Accipiter* contains nine species.