Onychotes gruberi, Type, (41703. California.)
41703 ¼ ½
Onychotes gruberi.
Genus ONYCHOTES, Ridgway.
Onychotes, Ridgway, P. A. N. S. Philad. Dec. 1870, 142. (Type, O. gruberi, nov. sp.)
Gen. Char. Bill short, the tip remarkably short and obtuse, and only gradually bent; cere on top about equal to the culmen, very broad basally in its transverse diameter, and ascending, in its lateral outline, on a line with the culmen; commissure only faintly lobed. Nostril nearly circular, with a conspicuous (but not central or bony) tubercle; cere densely bristled below the nostril, almost to its anterior edge; orbital region finely bristled. Tarsus very long and slender, nearly twice the length of the middle toe; toes moderate, the outer one decidedly longer than the inner; claws very long, strong, and sharp, and curved in about one quarter the circumference of a circle. Tibial feathers short and close, the plumes scarcely reaching below the joint. Feathers of the forehead, gular region, sides, and tibiæ, with white filamentous attachments to the end of the shafts. Wing very short, much rounded, and very concave beneath; fourth quill longest; first shorter than ninth; four primaries emarginated, and one sinuated, on inner webs; five sinuated on outer webs. Tail about two thirds as long as wing, rounded. Outstretched feet reaching beyond end of tail.
This genus has no very near relatives among the American Falconidæ, nor, indeed, among those of other portions of the world. It is, perhaps, most closely related to the genus Rupornis, of South America, from which, however, it is very distinct. It is represented by a single species, the type of which, supposed to have come from California, still remains unique.
The elongated legs, reaching considerably beyond the rather short tail, the close thigh-plumes, the long and extremely acute claws (somewhat like those of Rostrhamus), with the short, rounded, and very concave wing, are its most striking peculiarities. Besides these distinguishing features, the short, thick bill, very deep through the base, and the filamentous attachments to the shafts of the feathers of certain parts of the body, are also very characteristic. The latter feature may possibly be a mark of immaturity, but I have seen nothing like it in other Raptores, and it seems to be more analogous to the nuptial ornaments seen in the Cormorants (Phalocrocoracidæ).