Roraiman antbird explained

The Roraiman antbird (Myrmelastes saturatus) is a species of passerine bird in subfamily Thamnophilinae of family Thamnophilidae, the "typical antbirds". It is found in Brazil, Guyana, and Venezuela.[1]

Taxonomy and systematics

The Roraiman antbird has a complicated taxonomic history. It was previously considered as a subspecies of the spot-winged antbird (now M. leucostigma), which at times had been placed in genera Percnostola and Schistocichla. A 2007 study of the vocal characteristics of the then many subspecies of the spot-winged found significant differences between the taxa. Based on this evidence the Roraiman antbird was promoted to species status and given its English name.[2] [3] [4] A 2013 study finalized its move to genus Myrmelastes.[5]

The Roraiman antbird has two subspecies, the nominate M. s. saturatus (Salvin, 1885) and M. s. obscurus (Zimmer, JT & Phelps, WH, 1946).[1]

Description

The Roraiman antbird is 14to long and weighs 24to. Males of the nominate subspecies are mostly blackish slate, with wide white tips on their wing coverts. Females have a dark gray crown and dark cinnamon-brown upperparts. Their wings and tail are blackish brown with pale cinnamon-rufous tips on the wing coverts. Their face is gray. Their throat, breast, and belly are chestnut and their flanks and undertail coverts olive-brown. Both sexes have a brown or gray-brown iris and gray to black legs and feet. Males of subspecies M. s. obscurus are slightly blacker than nominate males and females have slightly darker underparts than nominate females.Males of both subspecies usually have a black bill though some have a gray base to the mandible. Females of both have a black maxilla and a gray mandible. [6] [7] [8]

Distribution and habitat

The Roraiman antbird is found in the eastern tepui region where eastern Venezuela, western Guyana, and far northern Brazil meet. The nominate subspecies occurs on Mount Roraima that straddles the Venezuela-Guyana border. Subspecies M. s. obscurus is found on tepuis other than Roraima in Venezuela's eastern Bolívar state and adjoining extreme northern Roraima state of Brazil. The species inhabits dense understorey in tall evergreen forest on the tepuis, where it favors the margins of clear, swift, streams on steep rocky slopes. In elevation it mostly occurs above 700m (2,300feet) in Brazil and Guyana, though there are records as low as 125-2NaN-2 in the latter country. In Venezuela it mostly occurs between 1000and.[6] [7] [8]

Behavior

Movement

The Roraiman antbird is believed to be a year-round resident throughout its range.[6]

Feeding

The Roraiman antbird's diet and foraging behavior are not known but are assumed to be very similar or identical to those of its former "parent" the spot-winged antbird, which see here.[6]

Breeding

Nothing is known about the Roraiman antbird's breeding biology.[6]

Vocalization

The Roraiman antbird's song is a "series of slowly starting, accelerating notes, sharply lowered in pitch at [the] end".[8] The species' "long call" is an abrupt high-pitched note followed by a downslurred whistle. Its other calls are apparently the same as those of the spot-winged antbird, an "abrupt unclear note given singly or in series of 2–5" and a "short rattle".[6] [9]

Status

The IUCN has assessed the Roraiman antbird as being of Least Concern. It has a restricted range; its population size is not known and is believed to be stable. No immediate threats have been identified. It is considered uncommon across its range; it does occur in several protected areas. "Regions inhabited by [the] species also encompass extensive areas of intact habitat which are not formally protected, but seem unlikely to be threatened by development in the near future."[6]

External links

Roraiman Antbird. BirdLife Species Factsheet

Notes and References

  1. Web site: Antbirds . IOC World Bird List . v 14.1 . Gill . Frank . Frank Gill (ornithologist) . Donsker . David . Rasmussen . Pamela . Pamela Rasmussen . January 2024 . 4 January 2024 .
  2. Braun . M.J. . Isler . M.L. . Isler . P.R. . Bates . J.M. . Robbins . M.B. . 2005 . Avian speciation in the Pantepui: the case of the Roraiman Antbird (Percnostola [''Schistocichla''] "leucostigma" saturata) . Condor . 107 . 2 . 327–341 . 10.1650/7647 . 1808/19238 . 15452230 . free .
  3. Isler . M.L. . Isler . P.R. . Whitney . B.M. . Zimmer . K.J. . 2007 . Species limits in the "Schistocichla" complex of Percnostola antbirds (Passeriformes: Thamnophilidae) . Wilson Journal of Ornithology . 119 . 1 . 53–70 . 10.1676/05-121.1 . 84340283 .
  4. Web site: Robbins . Mark . Proposal (240): Recognize Percnostola [''Schistocichla''] saturata (Thamnophilidae) as a species separate from P. leucostigma ]. South American Classification Committee of the American Ornithological Society . 2006 . July 30, 2024 .
  5. Isler, M.L., Bravo, G.A. and Brumfield, R.T. (2013). Taxonomic revision of Myrmeciza (Aves: Passeriformes: Thamnophilidae) into 12 genera based on phylogenetic, morphological, behavioral, and ecological data. Zootaxa 3717(4): 469–497.
  6. del Hoyo, J., N. Collar, and G. M. Kirwan (2020). Roraiman Antbird (Myrmelastes saturatus), 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.rorant2.01 retrieved July 30, 2024
  7. Book: Hilty, Steven L. . Birds of Venezuela . Princeton University Press . second . 2003 . Princeton NJ . Plate 41 . English .
  8. Book: van Perlo, Ber. A Field Guide to the Birds of Brazil . Oxford University Press . 2009 . New York . 256–257 . 978-0-19-530155-7 .
  9. Zimmer, K., M.L. Isler, and G. M. Kirwan (2020). Spot-winged Antbird (Myrmelastes leucostigma), 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.spwant3.01 retrieved July 29, 2024