SPECIES

Swynnerton's Robin Swynnertonia swynnertoni Scientific name definitions

Flemming P. Jensen
Version: 2.0 — Published February 4, 2022

Systematics

Systematics History

First described in 1906 by G. E. Shelley (5) from a specimen collected by C. F. M. Swynnerton in Zimbabwe. Shelley put it in the genus Erythracus (= Erithacus) with the European Robin (Erithacus rubecula), but in 1922 Roberts (6) assigned it to its own genus Swynnertonia. It has sometimes been placed in Pogonocichla (7, 8), but here we assign to the monotypic genus Swynnertonia.

Geographic Variation

Existing data suggest no differences in wing length or body mass between populations (4, FPJ). However, the two subspecies are described on the basis on differences in plumage colors (see Systematics: Subspecies).

Subspecies

Two subspecies recognized. Birds on Mt. Gorongosa in Mozambique have been described as a separate subspecies umbratica (9), but this population was subsequently considered a synonym of the nominate form (10).


EBIRD GROUP (MONOTYPIC)

Swynnerton's Robin (Udzungwa) Swynnertonia swynnertoni rodgersi Scientific name definitions

Systematics History

Swynnertonia swynnertoni rodgersi Jensen and Stuart, 1982, Bulletin of the British Ornithologists’ Club 102: 95–99; type locality = Mwanihana Forest, Udzungwa Mountains, Tanzania (11).

Distribution

Udzungwa Mountains and East Usambara Mountains in northeastern and central Tanzania.

Identification Summary

Adult male has yellow, rather than the orange-yellow breast of the nominate subspecies (11). In addition, the head is slate-gray, with the face and ear coverts slightly paler than the crown and center of throat, while the head of the nominate is pure gray and slightly darker (4). Some males from Udzungwa Mountains have an olive tint to the crown and nape, giving a slight “capped” appearance (4). The mantle, upper rump and scapulars are bright olive, contrasting with the gray head, nape, tail and uppertail coverts and lower rump. The nominate shows slightly less contrast between the duller mantle and head than rodgersi, and the uppertail coverts and rump are the same olive color as the mantle (4). The wings of rodgersi are almost pure slate-gray, with paler fringes to the remiges, and a slight olive wash on the coverts on some specimens, whereas the nominate shows a very slight olive wash to all wing feathers (4).

Adult female has the crown, nape and sides of head slightly paler and more olive-gray than in the nominate, and the mantle is a slightly brighter olive (4). The chin and throat above the gorget are creamy-white or buff, compared with slate gray in the nominate giving rodgersi a much less well-defined upper border to the throat gorget (4). The dark lower margin of the white gorget is also thinner on rodgersi and dark gray rather than black (4).


EBIRD GROUP (MONOTYPIC)

Swynnerton's Robin (Swynnerton's) Swynnertonia swynnertoni swynnertoni Scientific name definitions

Systematics History

Erythracus swynnertoni (Shelley, 1906), Bulletin of the British Ornithologists’ Club 16: 125–126; type locality = Chirinda Forest, Zimbabwe (5).

Distribution

Eastern Zimbabwe and Mt. Gorongosa and Mt. Mabu in north-central and central Mozambique.

Identification Summary

Male has breast orange-yellow, head pure gray and slightly darker in tone and slight olive-tinting to all wing feathers than rodgersi. Female has crown, nape and sides of head slightly paler and more olive-gray than rodgersi, mantle slightly brighter olive, chin and throat above the gorget slate gray. See Appearance: Plumages for a detailed description.

Related Species

Swynnerton’s Robin has a superficial resemblance to the White-starred Robin (Pogonocichla stellata), but is smaller, sexually dimorphic, lacks erectile tufts in front of the eyes, lacks pronounced rictal bristles, is almost entirely a ground-feeder and is sedentary (12). Subsequent studies of their phylogenetic relationships using molecular sequence data from mitochondrial genes and nuclear loci has suggested that Swynnertonia and Pogonocichla are sister taxa in an Erithacinae clade, which includes most of the African forest robins, but are probably not very closely related and should be maintained in separate genera (13).

Recommended Citation

Jensen, F. P. (2022). Swynnerton's Robin (Swynnertonia swynnertoni), version 2.0. In Birds of the World (P. G. Rodewald, Editor). Cornell Lab of Ornithology, Ithaca, NY, USA. https://doi.org/10.2173/bow.swyrob1.02