Chico's tyrannulet (''Zimmerius chicomendesi'') is a

Near Threatened A near-threatened species is a species which has been Conservation status, categorized as "Near Threatened" (NT) by the International Union for Conservation of Nature (IUCN) as that may be vulnerable to Endangered species, endangerment in the ne ...

species of

passerine A passerine () is any bird of the order Passeriformes (; from Latin 'sparrow' and '-shaped') which includes more than half of all bird species. Sometimes known as perching birds, passerines generally have an anisodactyl arrangement of their ...

bird in the family

Tyrannidae The tyrant flycatchers (Tyrannidae) comprise a Family (biology), family of passerine birds which is found virtually throughout North America, North and South America. It is the world's largest family of birds, with more than 400 species, and is ...

, the tyrant flycatchers. It is endemic to the area of Rio Madeirinha in Brazil.

Taxonomy and systematics

Chico's tyrannulet was first described by the ornithologists Bret Whitney and colleagues in 2013 and given the

binomial name In taxonomy, binomial nomenclature ("two-term naming system"), also called binary nomenclature, is a formal system of naming species of living things by giving each a name composed of two parts, both of which use Latin grammatical forms, altho ...

''Zimmerius chicomendesi''. Its common name and

specific epithet In Taxonomy (biology), taxonomy, binomial nomenclature ("two-term naming system"), also called binary nomenclature, is a formal system of naming species of living things by giving each a name composed of two parts, both of which use Latin gramm ...

honor the Brazilian environmentalist Chico Mendes. Taxonomic systems began recognizing the new species in 2016.BirdLife International (2016) Handbook of the Birds of the World and BirdLife International digital checklist of the birds of the world. Version 9. Available at: http://datazone.birdlife.org/userfiles/file/Species/Taxonomy/BirdLife_Checklist_Version_90.zip xls zipped 1 MBClements, J. F., P.C. Rasmussen, T. S. Schulenberg, M. J. Iliff, T. A. Fredericks, J. A. Gerbracht, D. Lepage, A. Spencer, S. M. Billerman, B. L. Sullivan, and C. L. Wood. 2016. The eBird/Clements checklist of birds of the world: v2016. Downloaded from https://www.birds.cornell.edu/clementschecklist/download/ retrieved August 31, 2016 Chico's tyrannulet is

monotypic In biology, a monotypic taxon is a taxonomic group (taxon) that contains only one immediately subordinate taxon. A monotypic species is one that does not include subspecies or smaller, infraspecific taxa. In the case of genera, the term "unisp ...

. It appears to be most closely related to the Mishana tyrannulet (''Zimmerius villarejoi'').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 28 September 2024. A classification of the bird species of South America. American Ornithological Society. https://www.museum.lsu.edu/~Remsen/SACCBaseline.htm retrieved September 29, 2024

Description

Chico's tyrannulet is about long; one male weighed . The sexes have the same plumage; males are larger than females. Adults have an olive-green crown, back, and rump. Their face is slightly paler and more green. Their wings are dull blackish with a faint olive cast. The wing

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 ...

have yellow edges and the secondaries and outer

primaries Primary elections or primaries are elections held to determine which candidates will run in an upcoming general election. In a partisan primary, a political party selects a candidate. Depending on the state and/or party, there may be an "open pri ...

have thinner yellow edges. Their tail is dull blackish with a faint olive cast. Their throat is pale green, their breast green washed with yellow, and their belly and undertail coverts bright yellow. They have a white iris, a brownish red

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 ...

, a reddish pink

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 ...

, and blackish legs and feet.del Hoyo, J., N. Collar, and G. M. Kirwan (2020). Chico's Tyrannulet (''Zimmerius chicomendesi''), 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.chityr1.01 retrieved November 11, 2024

Distribution and habitat

Chico's tyrannulet is a bird of Amazonian Brazil. It is found in southeastern Amazonas state from east of the

Madeira River The Madeira River ( ) is a major waterway in South America. It is estimated to be in length, while the Madeira-Mamoré is estimated near or in length depending on the measuring party and their methods. The Madeira is the biggest tributary of ...

to the Aripuanã and Madeirinha rivers. Its range might also extend further south into northeastern

Rondônia Rondônia () is one of the 26 states of Brazil, located in the northern subdivision of the country (central-western part). It is bordered by Acre (state), Acre in the west, Amazonas, Brazil, Amazonas in the north, Mato Grosso in the east, and Bo ...

and northwestern

Mato Grosso Mato Grosso ( – ) is one of the states of Brazil, the List of Brazilian states by area, third largest by area, located in the Central-West Region, Brazil, Central-West region. The state has 1.66% of the Brazilian population and is responsible ...

. It inhabits '' campina'' woodland and scrubland, a biome characterized by poor, often sandy or rocky, soils and generally low vegetation. The canopy is usually lower than about but has scattered trees as tall as .

Behavior

Movement

Chico's tyrannulet is believed to be a year-round resident.

Feeding

As far as is known, Chico's tyrannulet feeds mostly if not exclusively on fruits, especially those of mistletoes (

Loranthaceae Loranthaceae, commonly known as the showy mistletoes, is a family of flowering plants. It consists of about 75 genera and 1,000 species of woody plants, many of them hemiparasites. The three terrestrial species are '' Nuytsia floribunda'' (the ...

). Others of its genus also feed 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 ...

s so it is assumed that Chico's tyrannulet does so as well. It appears to forage mainly in pairs.

Breeding

Nothing is known about the breeding biology of Chico's tyrannulet.

Vocalization

Chico's tyrannulet has at least four vocalizations, all made by both sexes, though recordings are sparse. The most commonly heard is a call, "a distinctly double-noted 'tweep-tweep' (occasionally single- or triple-noted), with variants and different inflections". What is thought to be its dawn song is a single "tweep" note repeated at intervals of three to five seconds. It also makes a "call series" and a "snarl"; the latter is "probably only used in agonistic interactions".

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 Chico's tyrannulet as Near Threatened. It has a small range; its population size is not known and is believed to be decreasing. A principal threat is " e development of the BR-230 road which goes through much of the ''campina'' habitat in this species’s range, threatening this habitat. Development of this road may also involve quarrying for sand within the ''campina habitat'', and once complete it will make the area more accessible for logging and agriculture." "Although part of the species’ range is already nominally protected within the newly gazetted Campos Amazônicos National Park and some of the rest lie within indigenous territories, further protected areas should be declared within the distribution of both species, free from disturbance by road-building and other associated settlement activities."

References

{{Taxonbar, from=Q14857337 Chico's tyrannulet Birds of the Brazilian Amazon Endemic birds of Brazil Chico's tyrannulet