Dark markings on crown longitudinal. Ochraceous or white gular collar in form of a narrow band across jugulum.
A. carolinensis. Throat ochraceous, with sparse, narrow, transverse bars of black; jugular collar more whitish, with broader but more distant black bars. Crissum barred, and inner webs of primaries with black prevailing. Wing, 8.90; tail, 6.30. Hab. Louisianian region of the Eastern Province of United States (Florida and the Carolinas to Arkansas). Costa Rica.
B. Bristles of gape without lateral filaments; light tail-spaces covering both webs.
a. Throat black, with sparse, narrow, transverse bars of pale brown. Crissum barred, and inner webs of primaries with black greatly predominating.
A. macromystax. Crown pale brown and whitish very coarsely mottled with dusky; lower parts clouded with whitish, in conspicuous contrast with the ground color. Light tail patch restricted to less than terminal third, and decreasing in breadth toward the middle feathers. Bristles of gape enormously long and stout; bill compressed, nostrils large.
White patch on end of tail confined to three outer feathers, and decreasing very rapidly in extent to the inner. Wing, 6.60; tail, 5.30; rictal bristles, 1.40. Hab. Mexico (Mirador, La Parada) … var. macromystax.[106]
White patch on end of tail, on four outer feathers, and just appreciably decreasing in extent toward the inner. Wing, 7.00; tail, 5.50; rictal bristles, 2.00. Hab. Cuba … var. cubanensis.[107]
A. vociferus. Crown ash, finely mottled or minutely sprinkled with dusky; lower parts without whitish cloudings. White tail-patch covering more than terminal half, and decreasing in breadth toward the outer feather. Bristles of gape moderate, slender; bill weaker, less compressed, and nostrils smaller. Wing, 6.40; tail, 5.10; rictal bristles, 1.50 or less. Hab. Eastern Province of North America, south to Guatemala.
Dark markings of crown transverse. Gular collar pure white, covering nearly whole throat.
b. Throat pure white, without any markings. Crissum immaculate; inner webs of primaries with ochraceous very largely predominating.