Grallaria centralis Hosner, Robbins, Isler, & Chesser, 2020

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 : 20-21

Grallaria centralis Hosner, Robbins, Isler, & Chesser , new species

Oxapampa Antpitta

Includes population designated blakei 2 in the analysis.

Diagnosis. Upperparts dark reddish brown; anterior underparts slightly paler grading to pale yellow on lower belly and pinkish white on undertail coverts. Trilled long songs in combination with short songs consisting of a regularly repeated unmodulated note ( Fig. 13 ) distinguish G. centralis from all other populations except G. ayacuchensis . Vocal differences between G. centralis and G. ayacuchensis include short song note shape (rounded in G. centralis and downslurred in G. ayacuchensis ) and pattern of change in duration of long song notes (notes lengthen or remain constant in G. centralis and shorten in G. ayacuchensis ). The pace of long songs of G. centralis is slower than that of G. ayacuchensis ; although ranges of values do not overlap, means do not differ significantly, presumably because of small sample sizes.

Distribution. Endemic to Peru on east Andean slope from Huánuco south of the Río Huallaga through Pasco to Junín west of the Río Ene and north of the Río Mantaro, 2400–2700 m.

Holotype. Centro de Ornitología y Biodiversidad ( CORBIDI) AV-PAH653. Adult female shot in secondary forest and prepared as a study skin by P. A. Hosner on 4 October 2008 along the Río Satipo above Calabaza , Junín (11° 31’ S, 74° 52’ W, elevation 2400 m).

Description of holotype. Adult female. Overall plumage of upperparts dark reddish-brown (5YR 3/4), with throat and breast grading towards yellowish red-brown (5YR 4/6). Crown, nape, orbital feathers, lores, auriculars, back, rump, wing, uppertail coverts, and rectrices dark reddish-brown (5YR 3/4). Remiges dark reddish-brown (5YR 3/4) with the inner vane of each feather slightly duskier. Throat, breast, side of breast, and upper flanks yellowish red-brown (5YR 4/6), grading to antimony yellow (7.5YR 5/8) on center of belly and light buff on lower belly. Some feathers on belly have faint pale neutral gray mottling. Lower flanks grading to yellowish red-brown (5YR 4/6); undertail coverts antimony yellow (7.5YR 5/8). Ovary 8 x 6 mm, oviduct slightly enlarged and convoluted 2 mm; skull 100% pneumatized; moderate fat; mass 40.5 g; no bursa of Fabricius; stomach: insect parts, also bolus of insects in its bill; no molt. Iris dark brown, feet/legs slate gray, bill black.

Measurements of holotype. Bill length 12.0 mm, wing length 77.2 mm, tail length 45.7 mm, tarsus length 43.0 mm.

Paratopotypes. KU 133990 (male), KU 1133991 (male), CORBIDI Av-MFOR324 (male).

Paratypes. LSUMZ 170664 (male), 160081 (female) (specimen photographs App. 6, Fig. A 27) .

Etymology. The scientific name reflects the range of this species near the geographic center of Peru. The English name reflects the Province of Oxapampa, Pasco, Peru, where initial recordings were made by T. S. Schulenberg (ML 35960, 40063) and specimens (LSUMZ 106081, 170664) were collected by Louisiana State University expeditions in 1982 and 1985.

Remarks. Vocalizations of G. centralis and G. ayacuchensis differ sufficiently to meet our guidelines for distinguishing them as species, and this conclusion is supported by an mtDNA genetic distance of ~4%. Plumages of G. centralis and G. ayacuchensis are similar, but that of G. centralis is diagnostically darker and redder, especially on the upperparts. Holotype also cataloged as University of Kansas Biodiversity Institute (KU) 124422, tissue number 14767.

Figures

FIGURE 13. Songs of Grallaria centralis: (A) long song, Apalla-Andamarca Road, Junín, Peru (Athanas XC148512); (B) short song, Río Satipo, Junín (Hosner ML171921).