Grallaria blakei Graves, 1987

Isler, Morton L., Chesser, Terry, Robbins, Mark B., Cuervo, Andrés M., Cadena, Carlos Daniel & Hosner, Peter A., 2020, Taxonomic evaluation of the Grallaria rufula (Rufous Antpitta) complex (Aves: Passeriformes: Grallariidae) distinguishes sixteen species, Zootaxa 4817 (1), pp. 1-74 : 16-17

Grallaria blakei Graves, 1987

Chestnut Antpitta

Includes the population designated blakei 1 in the analysis.

Diagnosis. Overall plumage dusky reddish-brown, anterior underparts similar but paler posteriorly, often with faint barring. The long song of G. blakei is a lengthy trill ( Fig. 9 ), unlike the frequency-modulated note series of the apparently parapatric G. gravesi (see below). The long song of G. blakei differs from that of its geographic neighbor, G. cajamarcae , by initial intervals between notes that shorten in duration (lengthening in G. cajamarcae ) and by lack of frequency change in the final notes (rising in G. cajamarcae ). The lack of a short song in 36 recordings of G. blakei makes it highly probable that absence in its repertoire is not a recording artifact; no other population in the complex lacks a short song.

Distribution. Endemic to Peru on east Andean slope from Amazonas and San Martín, south and east of the Río Marañón, south to Huánuco, north of Río Huallaga, 1700–3000 m.

Plumage. Overall plumage of upperparts, including rectrices, remiges (primaries edged paler), crown and au- riculars, dusky reddish-brown (2.5YR 3/4), some slightly lighter and redder (to 2.5YR 4/6), shading to color of underparts in malar area. Overall plumage of anterior underparts yellowish red-brown (5YR 4/6–5/8); belly barred reddish-brown over dirty white with pinkish gray (5YR 6/2) tinge; flanks and undertail coverts reddish brown (5YR 4/4–4/6) (specimen photographs App. 6, Fig. A23).

Remarks. Grallaria blakei is distinguished vocally at the species level from neighboring populations, a distinction that is supported by the dark coloration noted in the description and by an mtDNA genetic distance of 6% or more from all other populations. Specimens and tissue samples are needed from the northern end of the distribution of G. blakei in the Cordillera Colán, Amazonas, Peru.

Figures

FIGURE 9. Song of Grallaria blakei: (A) long song, trail to Hacienda Paty, Huánuco, Peru (Walker ML236896).