Capnia

"The previously unknown female of the rare Arapahoe Snowfly, Capnia arapahoe, is described and illustrated for the first time from two specimens collected from the Front Range of
Colorado. The female terminalia is unique among sympatric species of Capnia and is compared to similar species.

KEY WORDS: Plecoptera, Capniidae, Capnia arapahoe, Colorado, snowfly"

The Arapahoe Snowfly, Arsapnia arapahoe (Nelson & Kondratieff), was recently discovered in six different first-order streams outside of the Cache la Poudre River basin where it was previously considered endemic. Specimens of A. arapahoe were always collected in much lower relative abundance, 1.18% (±2.3SD), than other sympatric adult capniids. The first mitochondrial deoxyribonucleic acid (DNA) barcodes for A. arapahoe and A. coyote (Nelson & Baumann) are presented and compared with those of A. decepta. DNA barcoding was not able to differentiate between A. arapahoe and A. decepta but it was able to show that A. coyote is a distinct species from its morphologically similar sister species, A. decepta.