Other Scientific Names
Sporophila obscura [Stotz et al. (1996)], Tiaris obscura [BirdLife International (2004)], Tiaris obscura [Sibley and Monroe (1990, 1993)]
First Described (Guide)
(d'Orbigny & Lafresnaye, 1837)
Habitat
Subtropical and tropical moist lowland and montane forest, subtropical and tropical moist and high altitude shrubland. From sea-level - 2,000 m.
Dull-colored Grassquit (Asemospiza obscura) [XC259829]
by John V. Moore from Zamora-Chinchipe: Tapichalaca-Zumba road, Ecuador (song)
Dull-colored Grassquit (Asemospiza obscura) [XC704213]
by Richard E. Webster from Reserva Paraba Frente Roja (Armonia), Departamento de Cochabamba, Bolivia (song)
Subspecies
Genus may belong in tanager family (Thraupidae). Appears to be part of a clade which also includes several Caribbean genera (Euneornis, Loxipasser, Melopyrrha, Loxigilla, Melanospiza), Bananaquit (Coereba flaveola), and "Darwin's finches" (Certhidea, Platyspiza, Pinaroloxias, Camarhynchus, Geospiza). Molecular data suggest that genus as currently constituted is polyphyletic. Further research is required. This species was previously included in genus in Sporophila, but skeletal features, nest type, song and molecular data indicate that it is better placed in present genus, and that it is sister to Sooty Grassquit (Asemospiza fuliginosa). Taxonomy complex: a detailed study of geographical variation of this species identified six diagnosable populations, each of which could be considered a subspecies. However, of the currently recognized subspecies, pacificus and haplochroma correspond to two of the six aforementioned populations, while nominate and pauper incorporate the remaining four.
The six identified populations are: those in range of haplochroma (as listed below), population from extreme southern Colombia and Ecuador (currently part of pauper), birds of dry northern valleys of Peru, in valleys of R Marañón and R Huallaga (currently part of pauper), those in range of pacificus (as listed below), non-coastal regions in Peru, south to La Paz, in Bolivia (currently part of nominate), and eastern slope from northern Bolivia south to northern Argentina (currently part of nominate). A thorough review is required.
The following 4 subspecies are recognised:
haplochroma (Todd, 1912) - Mountains of northern Colombia (Santa Marta) and northern Venezuela (Carabobo east to Monagas), also Andes south to Colombia (southern in Cauca Valley to south of Cauca Province).
pauper (von Berlepsch & Taczanowski, 1884) - Extreme southern Colombia (Nariño) southern on western slope of Andes to north-western Peru (to La Libertad and Cajamarca) and on eastern slope in northern Peru (south to San Martín and Loreto).
pacificus (Koepcke, 1963) - Coastal plain and slope in Peru from Ancash south to Arequipa.
obscurus (d'Orbigny & Lafresnaye, 1837) - Eastern slope of central Peru (from San Martin south, patchily, to Puno) and south through Andean slopes of Bolivia to north-western Argentina (south to Tucumán); also, probably non-breeding, in eastern lowlands of Bolivia (Santa Cruz and Chuquisaca), western Paraguay and northern Argentina (Chaco).
BirdLife International Species Factsheet