Coloration. — (I.) Adult males black with white spots on wing- coverts, white tips to rectrices (or lateral rectrices mostly white), and interscapulars pure white basally; adult females slate color or blackish above, with white markings as in adult males, under parts cinnamon-rufous or chestnut. (II.) Adult males brownish gray, brown, or rufescent above, the wing-coverts black with terminal white spots, the lateral rectrices also tipped with white; chin, throat, chest, and median portion of breast (sometimes abdomen also) black, the sides and flanks whitish, grayish or fulvous; adult females similar but without black on under parts.
Range. — Southern Mexico to Cayenne, southeastern Brazil, Bolivia, and Peru. (About seven species.)[1]
KEY TO THE SPECIES AND SUBSPECIES OF MICRORHOPIAS.
a. Upper parts black, the feathers of back pure white basally. (Microrhopias boucardi.)
- b. White tips to lateral rectrices smaller (5-7 mm. long on outermost rectrix).
- c. Flanks usually slate color. (Southeastern Mexico to Honduras.)
- cc. Flanks usually black. (Nicaragua to Panamá.)
- bb. White tip to lateral rectrices larger (9-12 mm., or more, long on outermost pair). (Colombia to Cayenne and western Ecuadór.)
aa. Upper parts not black.
- b. Feathers of back abruptly pure white basally; under parts wholly tawny or chestnut. (Microrhopias boucardi.)
- c. White tip to lateral rectrices smaller (about 5-7 mm. long on outermost rectrix) ; under parts lighter than chestnut, upper parts more grayish slaty.
- d. Under parts tawny
- c. White tip to lateral rectrices smaller (about 5-7 mm. long on outermost rectrix) ; under parts lighter than chestnut, upper parts more grayish slaty.
- dd. Under parts deep cinnamon-rufous or rufous-chestnut.
- cc. White tip to lateral rectrices larger (10-15 mm. long on outermost rectrix); under parts deep chestnut, upper parts more blackish slaty.
- bb. Feathers of back not white basally; under parts not tawny or chestnut. (Microrhopias grisea.)
- c. Sides of head, throat, chest, and breast uniform black. (Adult males.)
- d. General color of upper parts darker (deep grayish sepia or purplish brownish slate color).
- c. Sides of head, throat, chest, and breast uniform black. (Adult males.)
- ↑ I am very doubtful whether the group comprising Turdus griseus Boddaert, Formicivora intermedia' Cabanis, and Thamnophilus rufaler Lafresnaye and D'Orbigny should be included in this genus, for apart from the very different style of coloration, these species differ from Microrhopias proper in obsolete instead of conspicuously developed rictal bristles, much longer tarsus, and some other less marked characters.
