Circaetinae

Circaetinae is a bird of prey subfamily which consists of a group of medium to large broad-winged species.^[1][2] The group is sometimes treated as tribe Circaetini.^[3][4] These birds mainly specialise in feeding on snakes and other reptiles, which is the reason most are referred to as "snake-eagles" or "serpent-eagles". The exceptions are the bateleur, a more generalised hunter, and the Philippine eagle, which preys on mammals and birds.

Snake eagles
Philippine eagle (Pithecophaga jefferyi)
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Chordata
Class:	Aves
Order:	Accipitriformes
Family:	Accipitridae
Subfamily:	Circaetinae
Genera
See text.

All but one of the subfamily are restricted to warmer parts of the Old World: Spilornis and Pithecophaga in south Asia, the others in Africa. The short-toed eagle Circaetus gallicus migrates between temperate Eurasia and Africa, as well as being resident in India.

They have hooked beaks for tearing flesh from their prey, strong legs and powerful talons. They also have extremely keen eyesight to enable them to spot potential prey from a distance.

Taxonomy

The cladogram of the Circaetinae shown below is based on a molecular phylogenetic study of the Accipitridae by Therese Catanach and collaborators that was published in 2024.^[5]

Circaetinae	Spilornis – serpent eagles (6 species) Pithecophaga – Philippine eagle Terathopius – Bateleur Circaetus – snake eagles (6 species) + Dryotriorchis spectabilis

The following taxonomy is based on the International Ornithological Congress.^[6]

Image	Genus	Living Species
	Spilornis G.R. Gray, 1840	Crested serpent eagle, S. cheela Bawean serpent eagle, S. (cheela) baweanus Great Nicobar serpent eagle, S. klossi Mountain serpent eagle,S. kinabaluensis Sulawesi serpent eagle, S. rufipectus Philippine serpent eagle, S. holospilus Andaman serpent eagle, S. elgini
	Pithecophaga Ogilvie-Grant, 1896	Philippine eagle, P. jefferyi
	Circaetus Vieillot, 1816	Short-toed snake eagle, C. gallicus Beaudouin's snake eagle, C. beaudouini Black-chested snake eagle, C. pectoralis Brown snake eagle, C. cinereus Southern banded snake eagle, C. fasciolatus Western banded snake eagle, C. cinerascens
	Dryotriorchis Shelley, 1874	Congo serpent eagle, D. spectabilis
	Terathopius Lesson, 1830	Bateleur, T. ecaudatus
	Eutriorchis Sharpe, 1875^[note 1]	Madagascar serpent eagle, E. astur

Notes

1. Eutriorchis is genetically related to Gypaetus, and so might be classified with the Gypaetinae rather than Circaetinae. Lerner, Heather R. L.; Mindell, David P. (9 May 2006). "Accipitridae". The Tree of Life Web Project.

References

1. Lerner, Heather R.L.; Mindell, David P. (2005). "Phylogeny of eagles, Old World vultures, and other Accipitridae based on nuclear and mitochondrial DNA". Molecular Phylogenetics and Evolution. 37 (2): 327–346. doi:10.1016/j.ympev.2005.04.010. PMID 15925523.
2. Mindell, David P.; Fuchs, Jérôme; Johnson, Jeff A. (2018). "Phylogeny, Taxonomy, and Geographic Diversity of Diurnal Raptors: Falconiformes, Accipitriformes, and Cathartiformes". Birds of Prey. pp. 3–32. doi:10.1007/978-3-319-73745-4_1. ISBN 978-3-319-73744-7.
3. Edward C., Dickinson; Remsen Jr., James V., eds. (2013). The Howard and Moore Complete Checklist of the Birds of the World. Vol. 1: Non-passerines (4th ed.). Aves Press.
4. "ACCIPITRIDAE - Kites, Hawks and Eagles". Trust for Avian Systematics. Retrieved 27 March 2024.
5. Catanach, T.A.; Halley, M.R.; Pirro, S. (2024). "Enigmas no longer: using ultraconserved elements to place several unusual hawk taxa and address the non-monophyly of the genus Accipiter (Accipitriformes: Accipitridae)". Biological Journal of the Linnean Society: blae028. doi:10.1093/biolinnean/blae028.
6. Gill, Frank; Donsker, David; Rasmussen, Pamela, eds. (December 2023). "Hoatzin, New World vultures, Secretarybird, raptors". IOC World Bird List Version 14.1. International Ornithologists' Union. Retrieved 3 April 2024.