Range. — Southwestern Costa Rica to Cayenne and Ecuadór. (Two species.)[1]
MICROBATES CINEREIVENTRIS SEMITORQUATUS (Lawrence).
HALF-COLLARED ANTWREN.
Adults (sexes alike). — Pileum and hindneck plain warm-sepia brown; rest of upper parts plain sepia, the edges of greater wing- coverts and secondaries (especially the tertials) more rufescent, the rectrices decidedly darker terminally; sides of head (except lores) plain ochraceous-buff to deep tawny-buff, this color extending more or less over sides of neck; lores dull whitish broken by dusky bristle- like tips to feathers; anterior portion of malar region whitish; chin and throat white or grayish white, the latter bordered along each side by a broad but more or less broken streak of black; rest of under parts plain gray (no. 6 to mouse gray) passing into olive on flanks and under tail-coverts, the upper chest broadly streaked with black; maxilla brownish black with paler tomium, mandible dull whitish (horn color, flesh color, or straw yellowish in life); iris brown; legs and feet horn color (dark bluish gray in life).
Adult male. — Length (skins), 95-106 (100); wing, 51-57 (53.9); tail, 26.5-29.5 (27.7); culmen, 17.5-19 (18.1); tarsus, 22-24.5 (23.7); middle toe, 13-14.5 (13.6).[2]
Adult female. — Length (skins), 92-101 (96); wing, 50.5-53.5 (51.5); tail, 24-28 (26.3); culmen, 17-19 (18.1); tarsus, 20.5-24.5 (23.1); middle toe, 12.5-13.5 (12.9).[3]
Costa Rica (Jiménez; San Carlos; La Balsa; Rio Súcio; Pacuare; Guápiles; Guácimo; Cuábre; El Hogár; Carrillo; La Vijágua) and Panamá (Volcan de Chiriquí; Santiago de Verágua; Lion Hill; Panamá) ; Colombia (Antioquía) ?
- Ramphocænus semitorquatus Lawrence, Ann. Lyc. Nat. Hist. N. Y., vii, 1862, 469 (Lion Hill Station, Panamá,; coll. G. N. Lawrence); ix, 1868, 108 ("Valza," i. e. La Balsa, Costa Rica; crit.). — Salvin, Proc. Zool. Soc. Lond., 1867, 145 (Santiago de Verágua, Panamá; crit.); 1870, 195 (Calovévora, Panamá). — Frantzius, Journ. für Orn., 1869, 305 (Costa Rica). — Boucard, Proc. Zool. Soc. Lond., 1878, 61 (San Carlos, Costa Rica). — Zeledón, Anal. Mus. Nac. Costa Rica, i, 1887, 115 (Rio Súcio, Costa Rica).
- ↑ I have not seen M. collaris (Pelzeln), the type of the genus, and the above generic description is drawn up from M. cinereiventris and its subspecies semitorquatus.
- ↑ Thirteen specimens.
- ↑ Ten specimens, from Costa Rica.
Locality. Wing. Tail. Culmen. Tarsus. Middle
toe.males. Ten adult males from Costa Rica 53.9 27.6 18.1 23.7 13.6 Two adult males from western Panamá (Chiriquí) 53.7 28.7 18.5 23 13 One adult male from eastern Panamá (line of railway) 54 26.5 - 22.5 14
