Large, rare tinamou found in cloud forest along the east slope of the Andes. It is uniformly sooty gray, much darker and plainer than Gray Tinamou. Rusty lower underparts are hard to see in the field. Like other forest tinamous, it is far more likely to be heard than seen. Vocalizations include a low, drawn out coo, like a dove’s but longer, and a series of low, modulated whistles.