Family Ovenbirds (Furnariidae)

Least Concern

Pearled Treerunner (Margarornis squamiger)


Taxonomy

French: Anabasitte perlée German: Tropfenbrust-Stachelschwanz Spanish: Subepalo perlado
Taxonomy:

Anabates squamiger

d’Orbigny and Lafresnaye

, 1838,

Ayopaya, Cochabamba, Bolivia

.

Nominate race is morphologically distinct from the other two in its pale yellow vs off-white to whitish throat and underpart spotting (2), plain chestnut vs dark-scaled olive-brown crown (2), and shorter tail (effect size in males −1.4, score 1). All taxa have a variety of high-pitched vocalizations, ranging from short single notes (also doubled and tripled) to longer rattles, either at constant pitch or slightly rising and falling, and with variable pace; no significant differences have been found among races#R. Sight record in NW Argentina presumed to be of nominate, but may refer to an undescribed race. Three subspecies recognized.

Subspecies and Distribution
  • M. s. perlatus (Lesson, 1844) – Northern Pearled Treerunner – Sierra de Perijá and Andes of W Venezuela (Trujillo, Mérida, Táchira), Colombia (all three ranges), Ecuador, and N Peru N of R Marañón (Piura, N Cajamarca).
  • M. s. peruvianus Cory, 1913 – Andes of N & C Peru S of R Marañón (from S Cajamarca and Amazonas S to Cuzco).
  • M. s. squamiger (d’Orbigny & Lafresnaye, 1838) – Southern Pearled Treerunner – Andes of S Peru (Puno) and Bolivia (S to W Santa Cruz); sight record in NW Argentina (Salta).
  • Descriptive notes

    15–16 cm; 14–19 g. Strikingly patterned furnariid. Nominate race has sharply defined yellowish-buff supercilium extending from supraloral region back to collar,... read more

    Voice

    Song a rapid series of high-pitched, thin “tick” notes, lasting c. 1·5 seconds. Call a single high-... read more

    Habitat

    Montane evergreen forest and elfin forest; also locally ranging into Polylepis woodland,... read more

    Food and feeding

    Arthropods. Usually in pairs, less often singly or in groups of up to eight individuals; commonly in mixed-species flocks. Forages from mid... read more

    Breeding

    Fledglings seen in Jun in Venezuela, May in C Colombia, Jul in C Peru, and Mar and Dec in C Bolivia. Presumably monogamous. Nest a ball of... read more

    Movements

    Resident.

    Status and conservation

    Not globally threatened. Fairly common to common. Occurs in a number of protected areas, including Sierra Nevada and Guaramacal National parks, in Venezuela, Munchique... read more

    Recommended citation

    Remsen, J.V., Jr (2019). Pearled Treerunner (Margarornis squamiger). In: del Hoyo, J., Elliott, A., Sargatal, J., Christie, D.A. & de Juana, E. (eds.). Handbook of the Birds of the World Alive. Lynx Edicions, Barcelona. (retrieved from https://www.hbw.com/node/56532 on 21 August 2019).