Olivaceous Woodcreeper (Sittasomus griseicapillus) [XC748037]
by Jacob Wijpkema from Taquaral de Goi\u00e1s, Taquaral de Goi\u00e1s, Goi\u00e1s, Brazil (song)
Olivaceous Woodcreeper (Sittasomus griseicapillus) [XC333059]
by Jerome Fischer from Doutor Pedrinho, Doutor Pedrinho, Santa Catarina, Brazil (song)
Subspecies
Anatomical characters suggest no close relationship to any other genus. Taxonomy within present species is complex, requiring further research. Subspecies probably constitute more than one species, and systematics in need of comprehensive revision. On basis of size and gross plumage coloration, subspecies form five major groups, vocal differences among some of which, when combined with plumage variation, are sufficiently marked to suggest that full biological species may be involved: "griseicapillus group" (including amazonus, axillaris, transitivus and viridis) in Amazonia and Chaco, monotypic "aequatorialis group" on Pacific coast of South America, "griseus group" (including jaliscensis, gracileus, sylvioides, perijanus and tachirensis) in Central America and northern South America, monotypic "reiseri group" of north-eastern Brazil, and "sylviellus group" (with olivaceus) of eastern and south-eastern South America. Last two groups the most likely to represent separate species. Subspecies in in Central America and northern South America relatively similar in plumage to, but very different in voice, from Amazonian populations, some of which differ markedly from each other. Geographical variation largely clinal across much of Mexico through Central America to north-western South America, with birds becoming smaller and paler to south. Birds from north of Isthmus of Tehuantepec (Mexico) named as subspecies harrisoni considered indistinguishable from jaliscensis (both generally larger and greyer than birds farther south), although intermediates between harrisoni and sylvioides reported from Puebla; forms synonymized with sylvioides, which also intergrades with gracileus in southern Belize, have been described from western Panama south to northern Colombia (levis), eastern Panama veraguensis) and Colombia (enochrus), where numerous intermediates occur and marked individual variation apparent.
Proposed subspecies viridior, from eastern Bolivia, hardly distinguishable from and considered better merged with viridis, perhaps reflecting intergradation between latter and nominate.
The following 15 subspecies are recognised:
jaliscensis Nelson, 1900 - Mexico (in western from southern Nayarit, and in eastern from eastern San Luis Potosí and south-western Tamaulipas, south to Isthmus of Tehuantepec).
sylvioides Lafresnaye, 1850 - Central America, eastern and south of Isthmus of Tehuantepec from southern Mexico (Veracruz, central Tabasco, Oaxaca and Chiapas) southern on both slopes to north-western Colombia (northern Córdoba, northern Bolívar).
gracileus Bangs & Peters, JL, 1928 - South-eastern Mexico (Yucatán Peninsula, south to eastern Tabasco, southern Campeche and southern Quintana Roo) and adjacent northern Guatemala (Petén) and northern Belize.
perijanus Phelps & Gilliard, 1940 - North-eastern Colombia (north-western Magdalena, western Guajira) and extreme north-western Venezuela (Sierra de Perijá).
tachirensis Phelps & Phelps Jr, 1956 - Northern Colombia (southern Bolívar, Santander) and western Venezuela (south-western Táchira).
griseus Jardine, 1847 - Eastern Andes and coastal ranges in northern Venezuela (southern and western Lara south to Mérida and south-western Barinas, and central and south-eastern Falcón east to Sucre and northern Monagas). Also Tobago. Considered by some authors to be a distinct species, Western Olivaceous Woodcreeper (Sittasomus griseus).
aequatorialis Ridgway, 1891 - Pacific coast of South America, from western Ecuador (southern from western Esmeraldas) south to extreme north-western Peru (Tumbes).
amazonus Lafresnaye, 1850 - Western Amazonia, both northern and south of Amazon, from south-eastern Colombia (southern from southern Meta, Vichada and Guainía) and southern Venezuela (western and southern Amazonas), south to eastern Ecuador, eastern Peru and northern and western Brazil (east to R Negro and R Madeira, south to north-western Mato Grosso).
axillaris Zimmer, JT, 1934 - North-eastern Amazonia, north of Amazon, in south-eastern Venezuela (northern and central Amazonas, Bolívar), Guyana, French Guiana and northern Brazil (lower R Negro east to Amapá); probably occurs also in Surinam.
transitivus Pinto & Camargo, 1948 - South-eastern Amazonian Brazil, south of Amazon, eastern from at least R Tapajós (probably from R Madeira), south to north-eastern Mato Grosso.
viridis Carriker, 1935 - Amazonian Bolivia (Beni, La Paz, Cochabamba, northern and eastern Santa Cruz).
griseicapillus (Vieillot, 1818) - Central South America, in south-eastern Bolivia (southern Santa Cruz south-west to Tarija), south-central Brazil (south-western Mato Grosso, Mato Grosso do Sul) and northern and western Paraguay, south to north-central Argentina (south to Catamarca, Santiago del Estero and northern Santa Fe).
reiseri Hellmayr, 1917 - North-eastern Brazil (southern Maranhío, Ceará and Pernambuco south to Tocantins and northern and western Bahia).
olivaceus zu Wied-Neuwied, 1831 - Coastal eastern Brazil (south-eastern Bahia).
sylviellus (Temminck, 1821) - South-eastern South America, in south-eastern and southern Brazil (southern from south-eastern Goiás, Minas Gerais and Espírito Santo), south-eastern Paraguay, north-eastern Argentina (Misiones, north-eastern Corrientes) and north-eastern Uruguay.
BirdLife International Species Factsheet