White-throated xenops explained

The white-throated xenops (Xenops minutus) is a passerine bird in the Furnariinae subfamily of the ovenbird family Furnariidae. It is found in Argentina, Brazil, and Paraguay.[1]

Taxonomy and systematics

The white-throated xenops was formerly considered a subspecies of the plain xenops (now Xenops genibarbis, formerly X. minutus). HBW recognized the split by 2018 and the IOC followed suit in July 2023.[1] [2] However, the South American Classification Committee of the American Ornithological Society (SACC) and the Clements taxonomy retain it as a subspecies of the plain xenops. The SACC does state that Xenops minutus sensu lato might consist of more than one species.[3] [4]

The white-throated xenops is monotypic: No subspecies are recognized.[1]

Description

The white-throated xenops is about 12inchessigfig=2NaNinchesin (sigfig=2in) long and weighs about 10to. Its bill is wedge-shaped, fairly stubby, and slightly upturned. The sexes are alike and juveniles resemble adults. Adults have a conspicuous buff or whitish supercilium and a wide pure white malar stripe. Their upperparts are dull brown to rufous brown and unstreaked; their crown is darker and lightly streaked. Their tail is cinnamon with much black. Their wings are also cinnamon, with a wide tawny or ochraceous band on the flight feathers. Their throat is pale with little or no streaking. The rest of their underparts are plain dull grayish brown. Their iris is dark brown, their maxilla dull black, their mandible dull grayish white with a dark gray tip, and their legs and feet bluish gray.[5]

Distribution and habitat

The white-throated xenops is found in eastern and southeastern Brazil from Bahia state south to Santa Catarina state, eastern Paraguay, and northern Argentina's Misiones Province. It inhabits the interior and edges of a variety of forested landscapes including terra firme forests in the tropical lowlands, semideciduous forest, mature secondary forest, and gallery forest. In elevation it occurs from sea level to 1500m (4,900feet).[5] [6]

Behavior

Movement

The white-throated xenops is a year-round resident throughout its range.[5]

Feeding

The white-throated xenops' diet is almost entirely arthropods, both adult and larval. It has been recorded eating termites, Hymenoptera like ants and bees, beetles, katydids, millipedes, and spiders. It typically forages from the forest understory to its mid level but does ascend to the canopy. It often joins mixed-species foraging flocks. It captures prey by gleaning, hammering, chiseling, and prying with its upturned bill. It does much of its foraging on fairly thin dead branches, often rotten ones and those that have fallen into the understory, and also feeds along vines.[5]

Breeding

The white-throated xenops' breeding biology has not been studied but is assumed to be similar to that of its former "parent" species, the plain xenops, for which see here: Plain xenops#Breeding.[5]

Vocalization

The white-throated xenops' song is an "extr. high, hurried series of 5-10 x 'seep---' ".[6]

Status

The IUCN has assessed the white-throated xenops as being of Least Concern. It has a fairly large range, but its population size is not known and is believed to be decreasing. No immediate threats have been identified.

Notes and References

  1. Web site: Ovenbirds, woodcreepers . IOC World Bird List . v 13.2 . Gill . Frank . Frank Gill (ornithologist) . Donsker . David . Rasmussen . Pamela . Pamela Rasmussen . July 2023 . July 31, 2023 .
  2. HBW and BirdLife International (2022) Handbook of the Birds of the World and BirdLife International digital checklist of the birds of the world. Version 7. Available at: http://datazone.birdlife.org/userfiles/file/Species/Taxonomy/HBW-BirdLife_Checklist_v7_Dec22.zip retrieved December 13, 2022
  3. 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
  4. Clements, J. F., T. S. Schulenberg, M. J. Iliff, T. A. Fredericks, J. A. Gerbracht, D. Lepage, S. M. Billerman, B. L. Sullivan, and C. L. Wood. 2022. The eBird/Clements checklist of birds of the world: v2022. Downloaded from https://www.birds.cornell.edu/clementschecklist/download/ retrieved November 10, 2022
  5. Decker, S. (2020). Plain Xenops (Xenops minutus), version 1.0. In Birds of the World (T. S. Schulenberg, Editor). Cornell Lab of Ornithology, Ithaca, NY, USA. https://doi.org/10.2173/bow.plaxen1.01 retrieved August 16, 2023
  6. Book: van Perlo, Ber. A Field Guide to the Birds of Brazil . Oxford University Press . 2009 . New York . 228 . 978-0-19-530155-7 .