Herpsilochmus axillaris

Life-forms

Superregnum: Eukaryota
Cladus: Unikonta
Cladus: Opisthokonta
Cladus: Holozoa
Regnum: Animalia
Subregnum: Eumetazoa
Cladus: Bilateria
Cladus: Nephrozoa
Superphylum: Deuterostomia
Phylum: Chordata
Subphylum: Vertebrata
Infraphylum: Gnathostomata
Megaclassis: Osteichthyes
Cladus: Sarcopterygii
Cladus: Rhipidistia
Cladus: Tetrapodomorpha
Cladus: Eotetrapodiformes
Cladus: Elpistostegalia
Superclassis: Tetrapoda
Cladus: Reptiliomorpha
Cladus: Amniota
Classis: Reptilia
Cladus: Eureptilia
Cladus: Romeriida
Subclassis: Diapsida
Cladus: Sauria
Infraclassis: Archosauromorpha
Cladus: Crurotarsi
Divisio: Archosauria
Cladus: Avemetatarsalia
Cladus: Ornithodira
Subtaxon: Dinosauromorpha
Cladus: Dinosauriformes
Cladus: Dracohors
Cladus: Dinosauria
Ordo: Saurischia
Cladus: Eusaurischia
Subordo: Theropoda
Cladus: Neotheropoda
Cladus: Averostra
Cladus: Tetanurae
Cladus: Avetheropoda
Cladus: Coelurosauria
Cladus: Tyrannoraptora
Cladus: Maniraptoromorpha
Cladus: Maniraptoriformes
Cladus: Maniraptora
Cladus: Pennaraptora
Cladus: Paraves
Cladus: Eumaniraptora
Cladus: Avialae
Infraclassis: Aves
Cladus: Avebrevicauda
Cladus: Pygostylia
Cladus: Ornithothoraces
Cladus: Ornithuromorpha
Cladus: Carinatae
Parvclassis: Neornithes
Cohors: Neognathae
Cladus: Neoaves
Cladus: Telluraves
Cladus: Australaves
Ordo: Passeriformes
Subordo: Tyranni
Infraordo: Tyrannides
Parvordo: Thamnophilida

Familia: Thamnophilidae
Genus: Herpsilochmus
Species: Herpsilochmus axillaris
Subspecies: H. a. aequatorialis – H. a. axillaris – H. a. puncticeps – H. a. senex
Name

Herpsilochmus axillaris (Tschudi, 1844)

Type locality: Peru.

Synonyms

Thamnophilus axillaris (protonym)

References

Tschudi, J. J. von 1844. Avium conspectus quae in Republica Peruana reperiuntur et pleraeque observatae vel collectae sunt in itinere. Archiv für Naturgeschichte 10 (1): 262-317. Nicholai'schen Buchhandlung. Berlin. BHL Reference page. Original description p. 278 BHL

Links

IUCN: Herpsilochmus axillaris (Vulnerable)

Vernacular names
English: Yellow-breasted Antwren
español: Tiluchí pechiamarillo
français: Grisin à poitrine jaune

The yellow-breasted antwren (Herpsilochmus axillaris) is a species of bird in subfamily Thamnophilinae of family Thamnophilidae, the "typical antbirds". It is found in Colombia, Ecuador, and Peru.[2]
Taxonomy and systematics

The yellow-breasted antwren has these four subspecies:[2]

H. a. senex Bond, J & Meyer de Schauensee, 1940
H. a. aequatorialis Taczanowski & Berlepsch, 1885
H. a. puncticeps Taczanowski, 1882
H. a. axillaris (Tschudi, 1844)

Male near Zamora, Ecuador
Description

The yellow-breasted antwren is 11 to 12 cm (4.3 to 4.7 in) long and weighs 10 to 13 g (0.35 to 0.46 oz). Adult males of the nominate subspecies H. a. axillaris have a black crown and nape with white spots on the crown and a broken whitish supercilium on an otherwise mottled blackish and yellow-olive face. Their upperparts are olive-gray. Their wings coverts are black with yellow-tinged white edges and tips; their flight feathers are very dark gray. Their tail is mostly dark gray, with white tips and part of the edges of the inner feathers and mostly white outer feathers. Their throat and underparts are mostly pale yellowish olive with a yellow center to the belly. Adult females have a cinnamon-rufous crown, olive-buff upperparts, and darker olive underparts except for the yellow belly center. Their wings and tail are like the male's.[3][4]

Males of subspecies H. a. senex are paler than the nominate, with spots only on the center of their crown and a grayish white throat and breast. Males of subspecies H. a. puncticeps have olive-tinged and grayer upperparts than the nominate and less white on their tail feathers. Females have a dark olive-gray crown with a cinnamon-rufous tinge. Males of subspecies H. a. aequatorialis also have olive-tinged and grayer upperparts than the nominate. Their crown spots are only in the center; they have mostly pale yellow underparts with an olive wash on the sides.[3][5][6]
Distribution and habitat

The subspecies of the yellow-breasted antwren are found thus:[3]

H. a. senex: Colombia's Western and Central Andes between the departments of Risaralda and Cauca
H. a. aequatorialis: east slope of the Andes from Caquetá Department in southwestern Colombia south through eastern Ecuador into northern Peru as far as the Marañón River in the Department of Cajamarca
H. a. puncticeps: east slope of the Andes in east-central Peru from the Marañón south to the Department of Junín
H. a. axillaris: east slope of the Andes of southeastern Peru between the departments of Cuzco and Puno

The ranges of puncticeps and axillaris have a gap between them.[4]

The yellow-breasted antwren inhabits the interior and edges of humid evergreen forest, where it tends to favor the canopy. In elevation it ranges between 800 and 2,000 m (2,600 and 6,600 ft) in Colombia, between 800 and 1,700 m (2,600 and 5,600 ft) in Ecuador, and between 750 and 1,900 m (2,500 and 6,200 ft) in Peru.[3][4][5][6]
Behavior
Movement

The yellow-breasted antwren is thought to be a year-round resident throughout its range.[3]
Feeding

The yellow-breasted antwren's diet has not been detailed but includes insects and probably spiders. It usually forages in pairs, sometimes in family groups, but seldom by itself, and almost always as a member of a mixed-species feeding flock. It typically feeds from the forest's mid-level to its canopy; in the mid-level it favors vine tangles. It forages actively and methodically, and usually captures prey by gleaning from leaves, stems, and vines by reaching and sometimes lunging from a perch. It occasionally makes short sallies to hover-glean. It is not known to follow army ants.[3][4][5][6]
Breeding

One female yellow-breasted antwren was "ready to lay [an] egg" in March in Peru. Nothing else is known about the species' breeding biology.[3]

Dickcissel male perched on a metal pole singing, with neck stretched and beak open.

Songs and calls
Listen to yellow-breasted antwren on xeno-canto
Vocalization

The yellow-breasted antwren's song is "a rattle-like trill of dry notes".[3] It has been written as "tree-ee-ee-ee-ee-ee-ew" in Ecuador.[6] In northern Peru it is "tee-tee-TI-TI-titi'ti'tititititititer" and in Cuzco "chew tew-tew-TEE-TEE-ti-ti'ti'ti'tititi".[4] The species' call is "a short...downslurred whistle"[3] written as "tew" or "tchew"[4].
Status

The IUCN originally in 2004 assessed the yellow-breasted antwren as being of Least Concern, in 2012 as Vulnerable, and in 2022 again as of Least Concern. It has a large range and an unknown population size that is believed to be decreasing. "The primary threat to this species is accelerating deforestation for logging and agriculture. It is considered highly sensitive to human disturbance and as such is likely to suffer acutely as a result of forest fragmentation."[1] It is considered local and uncommon in Colombia, uncommon or rare in Ecuador, and rare to uncommon in Peru.[3][4][5][6] Its range includes some large protected areas.[3]
References

BirdLife International (2023). "Yellow-breasted Antwren Herpsilochmus axillaris". IUCN Red List of Threatened Species. 2023: e.T22701583A223586064. doi:10.2305/IUCN.UK.2023-1.RLTS.T22701583A223586064.en. Retrieved 4 March 2024.
Gill, Frank; Donsker, David; Rasmussen, Pamela, eds. (January 2024). "Antbirds". IOC World Bird List. v 14.1. Retrieved 4 January 2024.
Zimmer, K., M.L. Isler, and C. J. Sharpe (2020). Yellow-breasted Antwren (Herpsilochmus axillaris), 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.yebant2.01 retrieved March 4, 2024
Schulenberg, T.S., D.F. Stotz, D.F. Lane, J.P. O’Neill, and T.A. Parker III. 2010. Birds of Peru. Revised and updated edition. Princeton University Press, Princeton, New Jersey plate 167
McMullan, Miles; Donegan, Thomas M.; Quevedo, Alonso (2010). Field Guide to the Birds of Colombia. Bogotá: Fundación ProAves. p. 134. ISBN 978-0-9827615-0-2.
Ridgely, Robert S.; Greenfield, Paul J. (2001). The Birds of Ecuador: Field Guide. Vol. II. Ithaca: Cornell University Press. p. 412. ISBN 978-0-8014-8721-7.