About Penelope jacquacu Spix, 1825
Spix's guan (Penelope jacquacu Spix, 1825) has four recognized subspecies that differ in weight and plumage, with intergrades existing between them. Adults measure 66–76 cm (26–30 in) in length. For the nominate subspecies P. j. jacquacu, males weigh 1.24–1.36 kg (2.7–3.0 lb) while females average 1.14 kg (2.5 lb). Males of the subspecies P. j. orienticola weigh 1.40–1.78 kg (3.1–3.9 lb) and females weigh 1.27–1.72 kg (2.8–3.8 lb). The nominate subspecies has bronzy olive green plumage on its upperparts and bright reddish plumage on its underparts. The "Grant's" (granti) subspecies is much darker overall; its upperparts have a blue-green gloss and its red underside is dark. The plumage of P. j. speciosa is similar to that of the nominate subspecies. P. j. orienticola falls between the nominate subspecies and "Grant's" in both size and coloration. Spix's guan occurs in the upper Orinoco River and western Amazon River basins, across Bolivia, Brazil, Colombia, Ecuador, Guyana, Peru, Suriname, and Venezuela. From north to south, the order of subspecies ranges is granti, orienticola, jacquacu, and speciosa. It inhabits both non-flooded terra firma forest and seasonally flooded várzea forest. At higher elevations in Peru and Bolivia, it lives in cloud forest, while at lower elevations it occupies humid rainforest. This species is thought to be non-migratory (sedentary).
