The rufous-tailed xenops (''Microxenops milleri'') 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 Furnariinae subfamily of the ovenbird

family Family (from ) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). It forms the basis for social order. Ideally, families offer predictabili ...

Furnariidae. 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 ...

Brazil Brazil, officially the Federative Republic of Brazil, is the largest country in South America. It is the world's List of countries and dependencies by area, fifth-largest country by area and the List of countries and dependencies by population ...

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 ...

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 ...

Guyana Guyana, officially the Co-operative Republic of Guyana, is a country on the northern coast of South America, part of the historic British West Indies. entry "Guyana" Georgetown, Guyana, Georgetown is the capital of Guyana and is also the co ...

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 ...

Suriname Suriname, officially the Republic of Suriname, is a country in northern South America, also considered as part of the Caribbean and the West Indies. It is a developing country with a Human Development Index, high level of human development; i ...

Venezuela Venezuela, officially the Bolivarian Republic of Venezuela, is a country on the northern coast of South America, consisting of a continental landmass and many Federal Dependencies of Venezuela, islands and islets in the Caribbean Sea. It com ...

, and possibly

French Guiana French Guiana, or Guyane in French, is an Overseas departments and regions of France, overseas department and region of France located on the northern coast of South America in the Guianas and the West Indies. Bordered by Suriname to the west ...

.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 rufous-tailed xenops was originally placed in genus ''Microxenops'', which in the 1950s was merged into ''

Xenops ''Xenops'' is a genus in the bird family Furnariidae, the Ovenbird (family), ovenbirds. The genus comprises four species of xenops, all of which are found in Mexico, Central America and South America, particularly in tropical rain forests. They ...

''. By 2011 genetic data showed that it did not belong in ''Xenops'' and the previous ''Microxenops'' was restored.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 The rufous-tailed xenops is the only member of its genus and has no subspecies.

Description

The rufous-tailed xenops is long and weighs . It has a thin straight bill. The sexes are alike. Adults have a mostly blackish brown face with a buff

supercilium The supercilium is a plumage feature found on the heads of some bird species. It is a stripe which runs from the base of the bird's beak above its eye, finishing somewhere towards the rear of the bird's head.Dunn and Alderfer (2006), p. 10 Also k ...

. Their crown is blackish brown with golden-buff feather shafts. Their back is dark rufescent brown with wide buff streaks that fade by the lower back. Their rump and uppertail

coverts A covert feather or tectrix on a bird is one of a set of feathers, called coverts (or ''tectrices''), which cover other feathers. The coverts help to smooth airflow over the wings and tail. Ear coverts The ear coverts are small feathers behind t ...

are rufescent. Their tail is dark rufous. Their wing coverts are blackish with rufescent brown edges and their flight feathers are blackish with a wide rufous band at their base. Their chin and throat are pale yellowish buff with dark olive flecks and stripes on the latter. Their breast is bright buff with crisp narrow dark olive-brown streaks that fade to the belly. Their belly is bright golden-buff with much light brownish streaking. Their undertail coverts are bright buff with light ochraceous brown streaks. Their iris is brown to dark brown, their

maxilla In vertebrates, the maxilla (: maxillae ) is the upper fixed (not fixed in Neopterygii) bone of the jaw formed from the fusion of two maxillary bones. In humans, the upper jaw includes the hard palate in the front of the mouth. The two maxil ...

black to brownish, their

mandible In jawed vertebrates, the mandible (from the Latin ''mandibula'', 'for chewing'), lower jaw, or jawbone is a bone that makes up the lowerand typically more mobilecomponent of the mouth (the upper jaw being known as the maxilla). The jawbone i ...

blue-gray to leaden blue, and their legs and feet yellowish brown to olive.Remsen, Jr., J. V. (2022). Rufous-tailed Xenops (''Microxenops milleri''), version 1.1. In Birds of the World (S. M. Billerman, Editor). Cornell Lab of Ornithology, Ithaca, NY, USA. https://doi.org/10.2173/bow.rutxen1.01.1 retrieved August 17, 2023

Distribution and habitat

The rufous-tailed xenops is found from southeastern Colombia east through southern Venezuela and southern Guyana at least into Suriname, south through eastern Ecuador and Peru into northwestern Bolivia, and from there east into Amazonian Brazil to Mato Grosso. It might also occur in French Guiana, but 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 ...

classes it as hypothetical there because there are only undocumented sight records. The rufous-tailed xenops inhabits tropical lowland and

evergreen forest An evergreen forest is a forest made up of evergreen trees. They occur across a wide range of climatic zones, and include trees such as conifers and holly in cold climates, eucalyptus, live oak, acacias, magnolia, and banksia in more temperate zo ...

. It favors '' terra firme'' but also occurs in '' várzea'' forest. In elevation it occurs mostly below but reaches in Colombia and in Ecuador.

Behavior

Movement

The rufous-tailed xenops is a year-round resident throughout its range.

Feeding

The rufous-tailed xenops feeds on

arthropod Arthropods ( ) are invertebrates in the phylum Arthropoda. They possess an arthropod exoskeleton, exoskeleton with a cuticle made of chitin, often Mineralization (biology), mineralised with calcium carbonate, a body with differentiated (Metam ...

Orthoptera Orthoptera () is an order of insects that comprises the grasshoppers, locusts, and crickets, including closely related insects, such as the bush crickets or katydids and wētā. The order is subdivided into two suborders: Caelifera – gras ...

have been documented. It forages by itself and as part of

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

s, usually in the forest's sub-canopy and canopy. It mostly gleans from bark, leaves, and moss to capture its prey while hitching along slender branches and vines. It hangs almost upside down to reach their bottoms.

Breeding

Nothing is known about the rufous-tailed xenops' breeding biology.

Vocalization

The rufous-tailed xenops' song is a short, fast, high-pitched trill that rises and falls as it increases and decreases in volume. Its call has not been described.

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 rufous-tailed xenops as being of Least Concern. It has a very 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 rare to locally fairly common, with an apparently patchy distribution. It occurs in many protected areas.

References

{{Taxonbar, from=Q843631 rufous-tailed xenops Birds of the Amazon rainforest Birds of the Guiana Shield rufous-tailed xenops Taxonomy articles created by Polbot