Hierax erythrogenys Vigors, Proc. Zool. Soc. (1831), 96.
Microhierax erythrogenys Sharpe, Cat. Birds Brit. Mus. (1874), 1,
369; Hand-List (1899), 1, 273; McGregor and Worcester, Hand-List
(1906), 44; McGregor, Philippine Jour. Sci. (1907), 2, sec. A, 323.
Bohol (McGregor); Luzon (Meyer, Möllendorff, Everett, Steere Exp.,
Whitehead, McGregor); Mindoro (Bourns & Worcester, Porter); Negros
(Keay).
Adult (sexes similar).--Above, including wings and tail, black with a
dark green gloss; below white; sides, thighs, and under tail-coverts
black. Iris brown; bill and nails black; legs dark blue. Length of
a male from Mindoro, 160; wing, 110; tail, 68; culmen from cere,
11; tarsus, 20. A male from Bohol measures: Wing, 110; tail, 63;
culmen from cere, 13. A female from Luzon: Wing, 110; tail, 66;
culmen from cere, 12.
Young.--The immature male resembles the adult but the inner webs of
primaries are barred or mottled with white.
"Extremely local in its habits. Often found perching on a dead limb
at the top of some tree, and may be met with in exactly the same place
day after day. It feeds on insects and often leaves its perch on short
flights in pursuit of its prey, promptly returning, however. When shot
at but not killed it usually takes but a short flight, and returns
at once to its favorite perch. Small flocks frequently found together.
"Iris brown; legs and feet black; bill black. Nine specimens average,
179 in length; wing, 108; tail, 62; culmen, 13; tarsus, 22; middle
toe with claw, 21." (Bourns and Worcester MS.)