Astur Lacepede, Mem. de l'Inst., iii, p. 505 (1801).
Type, Falco palumbarius Linn.= Astur gentilis Linn.
The genus Astur, together with Accipiter, comprises the true Hawks as compared with the Falcons, Eagles, Buzzards, Harriers and Kites, which have longer and more pointed wings.
In this genus the bill is short and powerful, curving sharply from the cere and with a well-pronounced festoon ; the nostril is large, oval and horizontal, not vertical; either the third, fourth or fifth primary is longest or they are sub-equal; tail long and rather graduated ; tarsus about equal to tibia in length, long and stout, the toes powerful and the middle toe not greatly longer than the others; the tarsus is scutellated in front and behind, reticulated on the sides.
The Crested Goshawks were retained by Blanford in a separate genus, Lophospizias, but differ from Astur only in having a small crest. Even the common Goshawk, however, has the feathers of the nape rather long and semi-erectile and the difference does not appear to me to be of generic value.
Key to Species.
A. No definite crest.
A.Fourth, quill longest.
a1. Wing over 270 mm............... A. gentilis, p. 145.
b1. Wing under 240 mm................ A, badius, p. 147.
B.Third quill longest............... A. soloensis, p. 153.
B. A small but distinct nuchal crest ............... A. trivirgatus, p. 153.