Family Tyrant-flycatchers (Tyrannidae)

Least Concern

Southern Bentbill (Oncostoma olivaceum)


French: Bec-en-arc de Lawrence German: Gelbkehl-Krummschnabeltyrann Spanish: Mosquerito piquicurvo sureño

Todirostrum olivaceum


, 1862,

Lion Hill, Canal Zone, Panama


Sometimes considered conspecific with O. cinereigulare. Continued separation depends on presumed parapatric distribution (3); pale yellow-streaked pale olive vs whitish-streaked pale grey throat and breast, latter more contrasting and thus bolder (3); shorter wing (mean 10 males#R 47.4 mm vs 51.3) although fractionally longer bill (at least 1); but virtually identical in song. Monotypic.


C & E Panama (Caribbean slope from N Coclé and Pacific slope from Canal area) and NW Colombia (Chocó E to Magdalena and N Cundinamarca).

Descriptive notes

9 cm; 6–7 g. Distinctive bill with downward-arching culmen. Plumage is entirely olive above, whitish supraloral area; wings dusky, two indistinct greenish-yellow... read more


Guttural insect-like or toad-like trill, “grrrrrrr”, sometimes with introductory note, “pt-... read more


Humid tropical forest and forest edge, dense secondary-forest borders, sometimes lighter woodland,... read more

Food and feeding

Arthropods; occasionally eats small berries. Forages usually alone or in pairs, near ground in dense vegetation; often overlooked. Sallies... read more


Single nests in late Apr and early Aug in Panama; birds in breeding condition in Feb–Jun in Colombia. Small, roundish, domed nest... read more



Status and conservation

Not globally threatened. Fairly common; often overlooked. Numerous in Tayrona National Park, in Colombia.

Recommended citation

Clock, B. & Christie, D.A. (2019). Southern Bentbill (Oncostoma olivaceum). In: del Hoyo, J., Elliott, A., Sargatal, J., Christie, D.A. & de Juana, E. (eds.). Handbook of the Birds of the World Alive. Lynx Edicions, Barcelona. (retrieved from on 7 December 2019).