1 1/8-1 1/2" (28-38 mm). Male has long, triangular wings; female's rounded. Above, deep russet-orange with faint grayish-brown cast, both wings profusely blotched with black squares and bars, forming 3 bands parallel to margin, becoming haphazard near body. Fringes heavily checkered. Short white dash along FW costa. Below, FW dull orange-yellow with black spots repeated; HW ivory-white, with black capped orange spot row along outer margin; several orange patches, outlined in black, toward base.
Chisos Metalmark generally similar but much paler above and below, with FW band, not spot, on costa.
Caterpillar pale green, with bristles bunched into small clusters studding upper surfaces. Host plant is buckbrush (Ceanothus fendleri) in Colorado, probably also in Arizona.
1 brood; June-early August, occasionally May and September.
Brushy chaparral, foothills, and moister mountain canyons.
Colorado south through Arizona and N. New Mexico to Chihuahua, Mexico.
A key characteristic that distinguishes the metalmarks from many other butterflies is their reduced fore legs. Rather different from most other metalmarks, Nais Metalmarks sometimes have well-developed fore legs, which are nonetheless too small to be used for walking. Adults visit dogbane and other flowers, and settle on damp ground. In moist mountain canyons they tend to occur singly or in pairs, although sometimes several share a common area.