The pearled treerunner (''Margarornis squamiger'') 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

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, and possibly

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.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 pearled treerunner has three subspecies, the nominate ''M. s. squamiger'' (

d'Orbigny Alcide Charles Victor Marie Dessalines d'Orbigny (6 September 1802 – 30 June 1857) was a French naturalist who made major contributions in many areas, including zoology (including malacology), palaeontology, geology, archaeology and anthropol ...

& Lafresnaye, 1838), ''M. s. perlatus'' (

Lesson A lesson or class is a structured period of time where learning is intended to occur. It involves one or more students (also called pupils or learners in some circumstances) being taught by a teacher or instructor. A lesson may be either one ...

, 1844), and ''M. s. peruvianus'' (

Cory As a given name, Cory is used by both males and females. It is a variation of the name Cora, meaning "(the) Maiden", which is a title of the goddess Persephone. The name also can have origins from the Gaelic word ''coire'', which means "in a cauldr ...

, 1913).

Description

The pearled treerunner is long and weighs . The sexes have the same plumage. Adults of the nominate subspecies have a well-defined yellowish 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 ...

that extends to the nape, a dull reddish brown line behind the eye, dull yellowish buff and dark brown ear

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 ...

, and a dark brown moustacial area with tiny whitish spots that become streaks to the rear. Their forehead is dark brownish with pale rufous streaks and their crown dark reddish brown. Their collar is dull

rufescent Rufous () is a color that may be described as reddish-brown or brownish-red, as of rust or oxidised iron. The first recorded use of ''rufous'' as a color name in English was in 1782. However, the color is also recorded earlier in 1527 as a dia ...

brown with black-outlined yellowish buff streaks. Their back, rump, and uppertail coverts are bright reddish brown. Their wing coverts are bright reddish brown, their primary coverts dark

fuscous {{Short pages monitor