to rather large, strongly curved, acute, that of the hallux decidedly shorter than the digit.
Coloration. — Wings and tail (usually pileum also) cinnamon-rufous rest of upper parts plain brown; under parts plain pale brownish gray, light grayish brown, or dull buffy. Sexes alike.
Range. — Costa Rica to Ecuadór (at least).[1] (Many species.)[1]
KEY TO THE SPECIES OF ACRORCHILUS.
a. Pileum, at least, rufous. (Adults.)
- b. Loral, orbital, auricular, and malar regions rufous; crown without black streaks (Acrorchilus erythrops.)
- c. Middle pair of rectrices russet-brown. (Ecuadór.)
- cc. Middle pair of rectrices bright cinnamon-rufous, like rest of tail.
- d. Rufous of head less extended, the occiput and nape brown, like back; chest and lower throat light buffy olive. (Costa Rica and Panamá.)
- cc. Middle pair of rectrices bright cinnamon-rufous, like rest of tail.
- dd. Rufous of head more extended, involving occiput and nape; chest mouse gray fading into nearly ash gray on throat. (Northwestern Colombia.)
- bb. Loral, orbital, auricular, and malar regions buffy brownish, the superciliary region narrowly streaked with whitish; forehead and crown streaked with black. (Colombia to Ecuadór.)
aa. Pileum without rufous.
ACRORCHILUS ERYTHROPS RUFIGENIS (Lawrence).
LAWRENCE'S SPINETAIL.
Similar to A. e. erythrops Sclater,[5] of Ecuadór, but middle pair of rectrices bright cinnamon-rufous (hke other rectrices), instead of russet brown, cinnamon-rufous of head deeper and more extended (occupying whole of auricular and greater part of malar regions, as well as orbital, loral, supercillary, and supra-auricular regions as well
as forehead and crown), general coloration darker, and size larger.
- ↑ 1.0 1.1 On account of the very poor representation of species referred to the genus Siptornis by Dr. Sclater and other recent authorities, in the material which I have been able to examine, I can not give a very definite statement of the number of species or extent of the geographic range of this genus, which is so exceedingly distinct, structurally, from Siptornis that it is difficult to imagine why the fact has not sooner been realized. The only species examined by me in this connection are the following: A. erythrops (Sclater), A. hellmayri (Bangs), and A. pallida (Maximilian).
- ↑ Synallaxis erythrops Sclater, Proc. Zool. Soc. Lond., pt. xxviii, pt. i, May, 1860, 66 (Pallatanga, w. Ecuadór; coll. P. L. Sclater). Siptornis erythrops Sclater, Cat. Birds Brit. Mus., XV, 1890, 60, part. — A[crorchilus] erythrops erythrops Ridgway, Proc. Biol. Soc. Wash., xxii, April 17, 1909, 72, in text.
- ↑ Acrorchilus erythrops griseigularis Ridgway, Proc. Biol. Soc. Wash., xxii, April 17, 1909, 72 (San Antonio, Rio Call, n. w. Colombia; coll. E. A. and 0. Bangs).
- ↑ Synallaxis antisiensis Sclater, Proc. Zool. Soc. Lond., 1859, 457 (Cuenca, Ecuador; coll. P. L. Sclater). — Siptomis antisiensis Sclater, Cat. Birds Brit. Mus., xv, 1890, 59.
- ↑ See Key to the Species, this page.
