A Peterson Field Guide to Hummingbirds of North America (Peterson Field Guides) - Hardcover

WEDGE-TAILED SABREWING pl. 11 Campylopte rus curvipennis 4.75'5.25 in. (12'13.5 cm). Bill length: male 26'31 mm, female 23'28 mm; tail length: male 43'50 mm, female 38'44 mm.
This large hummingbird of eastern Mexico ranges north into southwestern Tamaulipas, the presumed origin of several other tropical species that have strayed into southern Texas; the potential exists for occurrence north of the Mexican border. The species gets its name from the modified shafts of its outer primaries, which are dramatically thickened and curved in adult males, less so in immature males and adult females. The function of this feature is unknown, though it may play a role in sound production or visual signaling during courtship displays.

Description A large hummingbird with a long wedge-shaped or graduated tail, the central pair of feathers being much longer than the outer pair and extending well beyond the wingtips. Upperparts are bright green to emerald green, with blue to violet-blue crown blending with green of nape. White spot behind eye contrasts strongly with dark gray cheek. Underparts are pale gray to whitish, often slightly darker laterally; undertail coverts may show buffy wash. Bill is long, straight to slightly decurved; lower mandible is pinkish at base. Sexes are similar. ADULT MALE: Very large, with metallic deep blue to violet- blue crown blending with bright green on nape. Shafts of outer primaries extremely broad, flattened and curved near base. Tail green above with increasing dark suffusion toward tips of outer feathers. R4'5 mostly blackish, often with faint paler mottling at tip. ADULT FEMALE: Similar to male but smaller, with less extensive satiny deep blue to violet-blue on crown. Tail similar to male's, but usually with faint lighter mottling or well-defined light gray tips on R3'5. IMMATURE MALE: Similar to adult male but crown duller, usually some pale mottling in outer tail feathers. IMMATURE FEMALE: Similar to adult female but crown very dull blue, light gray tips on R3'5 usually large, well defined. Immatures of both sexes may show buffy wash on underparts as well as pale edges on feathers of upperparts.

Text copyright © 2001 by Sheri L. Williamson. Reprinted by permission of Houghton Mifflin Company.