Family Tyrant-flycatchers (Tyrannidae)

Least Concern

Southern Beardless Tyrannulet (Camptostoma obsoletum)


Taxonomy

French: Tyranneau passegris German: Haubenkleintyrann Spanish: Mosquerito silbón
Taxonomy:

Muscicapa obsoleta

Temminck

, 1824,

Curitiba, Paraná, Brazil

.

Numerous races have been described, many weakly defined and intergrading broadly with neighbouring ones. Races form five geographically and morphologically discrete groups (Central American; N South American; W South American; W Amazonian; C South American), within which the various taxa could arguably be merged. Some of these groups may merit status of full species, as recently suggested by molecular analysis#R. Other proposed races include venezuelae (N Venezuela), indistinguishable from pusillum; and bogotense (upper Magdalena Valley), merged with caucae, as it represents a barely discernible intergrade between caucae and pusillum. Thirteen subspecies recognized.

Subspecies and Distribution
  • C. o. flaviventre P. L. Sclater & Salvin, 1865 – Central American Beardless Tyrannulet – Pacific coast of Costa Rica and both coasts of Panama.
  • C. o. orphnum Wetmore, 1957 – Coiba I, off SW Panama.
  • C. o. majus Griscom, 1932 – Pearl Is, off S Panama.
  • C. o. pusillum (Cabanis & Heine, 1860) – #RColombian Beardless Tyrannulet – N Colombia (Caribbean coast, Magdalena Valley S to Santander), N Venezuela (E to Sucre, S to Táchira, Barinas, Apure, N Amazonas and N Bolívar) and Trinidad.
  • C. o. caucae Chapman, 1914 – C Colombia (W slope of W Andes, Cauca Valley, upper Magdalena Valley, E slope of E Andes in W Meta).
  • C. o. napaeum (Ridgway, 1888) – S Venezuela (Amazonas, SE Bolívar), the Guianas, and N Brazil (E Amazonas, Pará, Amapá).
  • C. o. sclateri (Berlepsch & Taczanowski, 1884) – #RWestern Beardless Tyrannulet – W Ecuador and extreme NW Peru (Tumbes, N Piura).
  • C. o. maranonicum Carriker, 1933 – N Peru (extreme E Piura, and middle Marañón Valley in Amazonas, E Cajamarca and E Ancash).
  • C. o. griseum Carriker, 1933 – arid Pacific coast and slopes of W Peru (Lambayeque S to Lima).
  • C. o. olivaceum (Berlepsch, 1889) – Olive Beardless Tyrannulet – SE Colombia, E Ecuador, E Peru (S to C Ucayali) and W Brazil (S of Amazon in W Amazonas).
  • C. o. bolivianum J. T. Zimmer, 1941 – E slope of Andes in C Bolivia (E La Paz, Cochabamba) and NW Argentina (S to Tucumán); migrant to SE Peru#R.
  • C. o. cinerascens (Wied, 1831) – E Brazil (Maranhão E to Ceará, S to C Mato Grosso and Espírito Santo) and E Bolivia (E Santa Cruz).
  • C. o. obsoletum (Temminck, 1824) – Southern Beardless Tyrannulet – S Brazil (S Mato Grosso E to Rio de Janeiro, S to Rio Grande do Sul) S to Paraguay, C & NE Argentina (S to La Pampa and N Buenos Aires) and Uruguay.
  • Descriptive notes

    9·5–10·5 cm; 7–9 g. Drab tyrannulet with parulid-like bill, somewhat bushy crest. Nominate race is medium olive-grey above, slightly greyer on crown... read more

    Voice

    Thin, high whistle, “fleeeeer”, rising and falling slightly, sometimes with terminal... read more

    Habitat

    Variety of scrub habitats, including cactus desert, arid thorn-scrub, deciduous forest, gallery... read more

    Food and feeding

    Insects and spiders; also feeds extensively on berries, e.g. of mistletoes (Loranthaceae), and small fruits. Generally alone or in pairs;... read more

    Breeding

    Dec–Mar in Middle America and Venezuela, Feb–Apr (also Jul, Oct–Nov) in Trinidad, Sept–Dec in Surinam, Jan–... read more

    Movements

    Largely resident; not known to be migratory, but populations in extreme S may move N during austral... read more

    Status and conservation

    Not globally threatened. Fairly common to very common, and widespread; uncommon and local in some areas (e.g. E Ecuador). Occurs in numerous national parks and other... read more

    Recommended citation

    Fitzpatrick, J. (2018). Southern Beardless Tyrannulet (Camptostoma obsoletum). 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 https://www.hbw.com/node/57163 on 19 December 2018).