The long-tailed wood partridge is 29.0 to 42.2 cm (11.4 to 16.6 in) long and weighs 266 to 465 g (9.4 to 16.4 oz). Males are heavier than females, and adults of both sexes have a long tail though the female's is somewhat shorter. In adults, most of the head is black; the face has white streaks above and below the eye. The short crest on the crown is tipped with buff. The upper back is chestnut edged with gray and the lower back is olive brown, black, and tawny mottling. The breast is bluish gray with chestnut streaks. The juvenile is similar but with dark brown spots and less chestnut on the underparts. There are variations among the subspecies, but it is unknown if there are vocal differences or genetic ones other than plumage color among them.
The subspecies of the long-tailed wood partridge are distributed in four discrete zones.
The long-tailed wood partridge inhabits humid pine-oak, pine, fir, and montane evergreen forests with dense understories. In elevation it ranges between 1,200 and 3,300 m (3,900 and 10,800 ft).
The long-tailed wood partridge forages mainly on the ground, scratching in leaf litter, but also climbs in low branches to search. Its diet is mostly seeds and small fruits but also includes small arthropods and leaves.
The long-tailed wood partridge's breeding season extends from February to September, with nesting itself beginning in late April. Four nests have been described. One was a depression lined with grass in a natural cavity in the ground. One was a cavity of pine needles at the base of a rock and the others were at the base of a rock outcrop and under a small shub. The last two were not well concealed. Three of them each contained four eggs and the other six eggs.
The IUCN has assessed the long-tailed wood partridge as being of Least Concern. However, its main threat is "habitat loss by land use and land cover change caused by human activities."
