Figs 116–122, 161, 162, 217, 218. Map 12

Anarta subfuscula Grote, 1874b: 244.

Lasionycta subfuscula; McDunnough 1938: 71.

Scotogramma sedilis Smith, 1899: 43, syn. n.

Lasionycta sedilis; McDunnough 1938: 71.

Type Material. Anarta subfuscula: holotype ♀ [BMNH, examined]. Type locality: Colorado Territory. Scotogramma sedilis: lectotype ♀ [USNM, examined]. Type locality: Garfield County, Colorado. Th e lectotype female was designated by Todd (1982: 192).

Diagnosis. Males of L. subfuscula are unmistakable due to their wide bipectinate antennae (almost 5× shaft diameter). Females have a unique angled corpus bursae described in the L. subfuscula sub-group description. Females are difficult to separate from those of the L. perplexa sub-group without dissection, especially L. perplexa that is similar in size. Useful characters for differentiating them are listed under L. perplexa. In addition, the claviform spot of L. subfuscula is usually shorter than that of L. perplexa. Lasionycta subfuscula is less diffi cult to distinguish from L. perplexella and L. subalpina because females of these species tend to be smaller.

The CO1 sequences of Lasionycta subfuscula demonstrate larger differences than those of other Lasionycta species. Six haplotypes exist which differ by up to 2.09 % (Fig. 248).

Distribution and biology. Lasionycta subfuscula occurs from southwestern British Columbia and southwestern Alberta south to southern Oregon in the West and to southern Colorado and Utah in the Rocky Mountains. Adults fly in transition zone and subalpine forests. It has been collected from mid-June to early September.

Geographical variation. Populations of L. subfuscula are arranged in two subspecies.