Chaco Earthcreeper

The Chaco earthcreeper (''Tarphonomus certhioides'') is a species of bird in the Furnariinae subfamily of the ovenbird family Furnariidae. It is found in Argentina, Bolivia, and Paraguay, and as a vagrant in Brazil.Remsen, J. V., Jr., J. I. Areta, E. Bonaccorso, S. Claramunt, G. Del-Rio, A. Jaramillo, D. F. Lane, M. B. Robbins, F. G. Stiles, and K. J. Zimmer. Version 31 May 2023. Species Lists of Birds for South American Countries and Territories. https://www.museum.lsu.edu/~Remsen/SACCCountryLists.htm retrieved May 31, 2023

Taxonomy and systematics

The Chaco earthcreeper has at times been placed in genera ''Ochetorhynchus'' and ''Upucerthia'' but since the early 2000s has been placed in its current ''Tarphonomus''.Remsen, J. V., Jr., J. I. Areta, E. Bonaccorso, S. Claramunt, G. Del-Rio, A. Jaramillo, D. F. Lane, M. B. Robbins, F. G. Stiles, and K. J. Zimmer. Version 31 May 2023. A classification of the bird species of South America. American Ornithological Society. https://www.museum.lsu.edu/~Remsen/SACCBaseline.htm retrieved May 31, 2023 It has at times been considered conspecific with the other member of ''Tarphonomus'', the Bolivian earthcreeper (''T. harterti''). The two of them are sisters to the rusty-winged barbtail (''Premnornis guttuliger''), and these three are in turn sisters to the tuftedcheeks of genus '' Pseudocolaptes''.

The Chaco earthcreeper has three subspecies, the nominate ''T. c. certhoides'' (d'Orbigny & Lafresnaye, 1838), ''T. c. luscinia'' ( Burmeister, 1860), and ''T. c. estebani'' ( Wetmore & Peters, JL, 1949).

Description

The Chaco earthcreeper is about long and weighs . It is a small earthcreeper with a long and very slightly decurved bill. The sexes' plumages are alike. Adults of the nominate subspecies have an indistinct orange-rufous supercilium on a mostly dark brown face. Their forehead is dull orange-rufous, their crown and back dull dark brown, and their rump and uppertail coverts somewhat rufescent brown. Their tail is generally dull brown with progressively more rufous from the central to the outermost feathers. Their wings are slightly more rufous brown than the back with rufous bases on the flight feathers. Their throat and cheeks are white. Their breast and belly are brown and their flanks and undertail coverts rufescent. Their iris is brown, their maxilla blackish to dark gray, their mandible slate gray to pinkish gray, and their legs and feet blackish to dark gray. Juveniles have an overall rufous tinge but their forehead is less rufous than adults'.Remsen, Jr., J. V. (2020). Chaco Earthcreeper (''Tarphonomus certhioides''), version 1.0. In Birds of the World (J. del Hoyo, A. Elliott, J. Sargatal, D. A. Christie, and E. de Juana, Editors). Cornell Lab of Ornithology, Ithaca, NY, USA. https://doi.org/10.2173/bow.chaear1.01 retrieved August 20, 2023

Subspecies ''T. c. luscinia'' has grayer (less rufescent) upperparts, more rufous on the wings, and paler underparts than the nominate. ''T. c. estebani'' has a paler back, a duller breast and belly, and no rufescent tinge on the flanks compared to the nominate.

Distribution and habitat

Subspecies ''T. c. estebani'' of the Chaco earthcreeper is found in Santa Cruz Department in south central Bolivia, in northern Argentina, and in western Paraguay. ''T. c. luscinia'' is found in the western Argentina provinces of San Juan, La Rioja, Córdoba, Mendoza, and San Luis. The nominate ''T. c. certhoides'' is found in northeastern Argentina from Río Negro Province north to Formosa Province. It has also occurred once in Rio Grande do Sul, Brazil.Repenning, M., Chiarani, E., Pereira, M.S. and Fontana, C.S. (2012). First record of the Chaco Earthcreeper ''Tarphonomus certhioides'' (Furnariidae) in Brazil. Rev. Bras. Orn. 20(4): 453–454.

Subspecies ''T. c. estebani'' and ''T. c. certhoides'' of the Chaco earthcreeper inhabit dense scrublands and deciduous woodland in the Chaco Basin, especially areas with terrestrial bromeliads. ''T. c. luscinia'' inhabits slopes with dense shrubs in the Andean foothills. In elevation the species occurs up to .

Behavior

Movement

The Chaco earthcreeper is a year-round resident throughout its range.

Feeding

The Chaco earthcreeper feeds on arthropods. It usually forages alone, gleaning prey from the ground and possibly from low vegetation.

Breeding

The Chaco earthcreeper breeds during the austral summer. It is thought to be monogamous. It builds a stick nest in a bush or tree, in a cavity in a tree, rock face, or old building, or in an old nest of a '' Furnarius'' hornero. It pads the floor of the nest with softer material such as hair, grass, and other plant fibers. The clutch size is three or four eggs. The incubation period, time to fledging, and details of parental care are not known.

Vocalization

The Chaco earthcreeper's song is "a series of 5–15 loud, squeaky penetrating 'chiqui' notes that increase in intensity nddescend in pitch". Its call is "a loud whistled 'tééoo' or 'tuéét' ".

Status

The IUCN has assessed the Chaco earthcreeper as being of Least Concern. It has a large range, and though its population size is not known it is believed to be stable. No immediate threats have been identified. It is considered fairly common in most of its range and occurs in at least one protected area.

References

{{Taxonbar, from=Q1274631

Chaco earthcreeper
Birds of the Gran Chaco
Chaco earthcreeper
Taxonomy articles created by Polbot