Figs 63, 64, 177. Map 15
Scotogramma discolor Smith, 1899: 42.
Lasiestra discolor; McDunnough 1938: 72.
Lasionycta discolor; Lafontaine et al. 1986: 264.
Lasiestra klotsi Richards, 1943: 87, syn. n.
Lasionycta klotsi; Lafontaine et al. 1986: 164.
Type material. Scotogramma discolor: holotype ♁ [ USNM, examined]. Type locality: Park County, Colorado. Lasiestra klotsi: holotype ♁ [ ANSP, Philadelphia, examined]. Type locality: Hall Valley, Park County, Colorado.
Diagnosis. Lasionycta discolor occurs in the central Rocky Mountains. It can be recognized by the combination of gray forewing with patches of white to greenishyellow scales, most pronounced in the subterminal area, and gray and white dorsal hindwing. The ventral hindwing is white with a gray discal spot, postmedial line, thin marginal band, and veins. Th e male valve of L. discolor is similar to that of L. uniformis but is slightly narrower. The number of basal cornuti on the vesica is variable, but there are often between four and six. Th e female genitalia are indistinguishable from those of L. uniformis.
Lasionycta discolor occurs with L. uniformis fusca and resembles pale specimens of it. Th e dorsal hindwing of L. discolor has white on both sides of the postmedial line, which is weakly dentate below the cell, and the ventral hindwing has dark veins and an uninterrupted marginal band. Th e hindwing of L. u. fusca is darker gray without white areas and the postmedial line is sinuous but not dentate. Th e underside lacks dark scaling on the veins and the marginal band contains pale scales. Th e vesica of L. uniformis has fewer cornuti than that of L. discolor, usually 0–3.
Distribution and biology. Lasionycta discolor occurs in the Rocky Mountains of Colorado and on the Beartooth Plateau in Wyoming. It flies over alpine tundra and is both diurnal and nocturnal. Most adults have been collected in late July.
Remarks. Th is species was known as L. klotsi for many years.