The tawny-faced gnatwren or half-collared gnatwren (''Microbates cinereiventris'') is a species of

bird Birds are a group of warm-blooded vertebrates constituting the class (biology), class Aves (), characterised by feathers, toothless beaked jaws, the Oviparity, laying of Eggshell, hard-shelled eggs, a high Metabolism, metabolic rate, a fou ...

in the family Polioptilidae, the gnatcatchers. It is found in

Bolivia Bolivia, officially the Plurinational State of Bolivia, is a landlocked country located in central South America. The country features diverse geography, including vast Amazonian plains, tropical lowlands, mountains, the Gran Chaco Province, w ...

Colombia Colombia, officially the Republic of Colombia, is a country primarily located in South America with Insular region of Colombia, insular regions in North America. The Colombian mainland is bordered by the Caribbean Sea to the north, Venezuel ...

Costa Rica Costa Rica, officially the Republic of Costa Rica, is a country in Central America. It borders Nicaragua to the north, the Caribbean Sea to the northeast, Panama to the southeast, and the Pacific Ocean to the southwest, as well as Maritime bo ...

Ecuador Ecuador, officially the Republic of Ecuador, is a country in northwestern South America, bordered by Colombia on the north, Peru on the east and south, and the Pacific Ocean on the west. It also includes the Galápagos Province which contain ...

Nicaragua Nicaragua, officially the Republic of Nicaragua, is the geographically largest Sovereign state, country in Central America, comprising . With a population of 7,142,529 as of 2024, it is the third-most populous country in Central America aft ...

Panama Panama, officially the Republic of Panama, is a country in Latin America at the southern end of Central America, bordering South America. It is bordered by Costa Rica to the west, Colombia to the southeast, the Caribbean Sea to the north, and ...

, and

Peru Peru, officially the Republic of Peru, is a country in western South America. It is bordered in the north by Ecuador and Colombia, in the east by Brazil, in the southeast by Bolivia, in the south by Chile, and in the south and west by the Pac ...

Taxonomy and systematics

The

International Ornithological Committee The International Ornithologists' Union (IOU) is an international organization for the promotion of ornithology. It links basic and applied research and nurtures education and outreach activities. Specifically, the IOU organizes and funds global co ...

(IOC) and

BirdLife International BirdLife International is a global partnership of non-governmental organizations that strives to conserve birds and their habitats. BirdLife International's priorities include preventing extinction of bird species, identifying and safeguarding i ...

(BLI) recognize seven subspecies of tawny-faced gnatwren:HBW and BirdLife International (2020) Handbook of the Birds of the World and BirdLife International digital checklist of the birds of the world. Version 5. Available at: http://datazone.birdlife.org/userfiles/file/Species/Taxonomy/HBW-BirdLife_Checklist_v5_Dec20.zip xls zipped 1 MBretrieved May 27, 2021 *''M. c. semitorquatus''

Lawrence Lawrence may refer to: Education Colleges and universities * Lawrence Technological University, a university in Southfield, Michigan, United States * Lawrence University, a liberal arts university in Appleton, Wisconsin, United States Preparator ...

(1862) *''M. c. albapiculus'' Olson (1980) *''M. c. magdalenae'' Chapman (1915) *''M. c. cinereiventris''

Sclater Philip Lutley Sclater (4 November 1829 – 27 June 1913) was an English lawyer and zoologist. In zoology, he was an expert ornithologist, and identified the main zoogeographic regions of the world. He was Secretary of the Zoological Society ...

(1855) *''M. c. unicus'' Olson (1980) *''M. c. hormotus'' Olson (1980) *''M. c. peruvianus'' Chapman (1923) However, the South American Classification Committee of the

American Ornithological Society The American Ornithological Society (AOS) is an ornithological organization based in the United States. The society was formed in October 2016 by the merger of the American Ornithologists' Union (AOU) and the Cooper Ornithological Society. Its ...

(SACC/AOS) and the

Clements taxonomy ''The Clements Checklist of Birds of the World'' is a book by Jim Clements which presents a list of the bird species of the world. The most recent printed version is the sixth edition (2007), but has been updated yearly, the last version in 202 ...

have not accepted the three subspecies that Olson described but include them within ''M. c. peruvianus''.Remsen, J. V., Jr., J. I. Areta, E. Bonaccorso, S. Claramunt, A. Jaramillo, D. F. Lane, J. F. Pacheco, M. B. Robbins, F. G. Stiles, and K. J. Zimmer. Version 23 May 2021. A classification of the bird species of South America. American Ornithological Society. https://www.museum.lsu.edu/~Remsen/SACCBaseline.htm retrieved May 24, 2021Clements, J. F., T. S. Schulenberg, M. J. Iliff, S. M. Billerman, T. A. Fredericks, B. L. Sullivan, and C. L. Wood. 2019. The eBird/Clements Checklist of Birds of the World: v2019. Downloaded from https://www.birds.cornell.edu/clementschecklist/download/ Retrieved August 15, 2019

Description

The tawny-faced gnatwren is long and weighs . The nominate subspecies has a rusty face with a rufous crown and a thin black stripe behind the eye. A wide black malar stripe ("moustache") separates its face from the white throat and upper breast; the last has thin black stripes. Its back is brown and its underparts are gray. The sexes are alike. The other subspecies differ in the intensity of their cheek and underparts colors, and some do not have the black stripe behind the eye.Atwood, J. L., S. B. Lerman, and E. de Juana (2020). Tawny-faced Gnatwren (''Microbates cinereiventris''), 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.tafgna1.01 retrieved May 28, 2021

Distribution and habitat

The subspecies of tawny-faced gnatwren are distributed thus: *''M. c. semitorquatus'', the Caribbean slope from southeastern Nicaragua through Costa Rica and Panama into extreme northwestern Colombia, and also the Pacific slope of central Panama *''M. c. albapiculus'', the Cauca Valley of northern Colombia *''M. c. magdalenae'', the

Magdalena River Valley The Magdalena River (, ; less commonly ) is the main river of Colombia, flowing northward about through the western half of the country. It takes its name from the biblical figure Mary Magdalene. It is navigable through much of its lower reaches, ...

of northern Colombia *''M. c. cinereiventris'', from Panama's

Darién Province Darién (, ; ) is a Provinces of Panama, province in Panama whose capital city is La Palma, Darién, La Palma. With an area of , it is located at the eastern end of the country and bordered to the north by the province of Panamá Province, Panam ...

south along the Pacific coast through Colombia to southwestern Ecuador. *''M. c. unicus'', central Colombia *''M. c. hormotus'' , southern Colombia, eastern Ecuador, and northeastern Peru *''M. c. peruvianus''

sensu stricto ''Sensu'' is a Latin word meaning "in the sense of". It is used in a number of fields including biology, geology, linguistics, semiotics, and law. Commonly it refers to how strictly or loosely an expression is used in describing any particular c ...

, eastern Peru and western Bolivia The tawny-faced gnatwren generally inhabits the lower strata of wet, humid,

primary Primary or primaries may refer to: Arts, entertainment, and media Music Groups and labels * Primary (band), from Australia * Primary (musician), hip hop musician and record producer from South Korea * Primary Music, Israeli record label Work ...

and

secondary forest A secondary forest (or second-growth forest) is a forest or woodland area which has regenerated through largely natural processes after human-caused Disturbance (ecology), disturbances, such as Logging, timber harvest or agriculture clearing, or ...

, mostly below elevation. The exception is ''M. c. unicus'', which is "known only from a single specimen... ollectedon an undetermined date between 1930 and 1943" in a much drier biome.

Behavior

Feeding

The tawny-faced gnatwren's diet is primarily ants and other insects but also includes spiders. It forages through foliage and leaf litter while hopping through undergrowth near the ground. It regularly joins

mixed-species foraging flock A mixed-species feeding flock, also termed a mixed-species foraging flock, mixed hunting party or informally bird wave, is a flock (birds), flock of usually insectivorous birds of different species that join each other and move together while fora ...

s but rarely follows

army ant The name army ant (or legionary ant or ''marabunta'') is applied to over 200 ant species in different lineages. Because of their aggressive predatory foraging groups, known as "raids", a huge number of ants forage simultaneously over a limited ...

swarms.

Breeding

Information on the tawny-faced gnatwren's breeding

phenology Phenology is the study of periodic events in biological life cycles and how these are influenced by seasonal and interannual variations in climate, as well as habitat factors (such as elevation). Examples include the date of emergence of leav ...

is sparse. Nesting has been recorded in April in Costa Rica and between December and May in Colombia. The one fully-described nest was constructed of green moss with a soft inner lining. It was attached to the trunk and a limb of a broadleaf shrub and contained two eggs.

Vocalization

The tawny-faced gnatwren's song is "a series of soft, clear, plaintive notes, 'teeeeea' or 'teeeéuw'

Its most common call is "a nasal, complaining 'nyeeeh' or 'nyaaah'

It also makes a chatte

Status

The

IUCN The International Union for Conservation of Nature (IUCN) is an international organization working in the field of nature conservation and sustainable use of natural resources. Founded in 1948, IUCN has become the global authority on the status ...

has assessed the tawny-faced gnatwren as being of Least Concern. However, "Three races...are primarily restricted to ecoregions considered...to be seriously threatened as a result of habitat loss".

References

{{Taxonbar, from=Q637143 tawny-faced gnatwren Birds of Costa Rica Birds of Panama Birds of the Ecuadorian Amazon Birds of Peruvian Amazonia Birds of Tumbes-Chocó-Magdalena tawny-faced gnatwren tawny-faced gnatwren Taxonomy articles created by Polbot