Bolshecapnia RICKER 1965

Bolshecapnia Ricker, 1965

Type species Capnia (Bolshecapnia) gregsoni Ricker, 1965 = Bolshecapnia gregsoni (Ricker), original designation

Male characteristics: 1. Epiprocts are relatively wide, tongue-shaped structures that bear a pair of sclerotized, acute lateral hooks (Figs. 1-2, 7, 28). 2. Patches of spongy-appearing tissue occur dorsoapically along the lateral margins of the epiproct (Fig. 12). 3. A relatively wide and long median dorsal groove is present on the epiproct (Figs. 7-8). 4. A well developed, hairy vesicle arises from the intersegmental membrane between the 8 th and 9 th abdominal sterna (Figs. 22, 32). 5. Tergum 9 modified with patches of short, thick setae, or with thimble, or cone-shaped dorsal knobs (Figs. 2, 9-10, 27-28).

Female characteristics: 1. Subgenital plates project slightly beyond the posterior margin of sternum 8, often reaching to, or beyond the sclerotized base of sternum 9 (Figs. 5-6, 33-34). 2. Subgenital plate usually sclerotized, but rather uniformly, without a distinctive pattern of pale and dark pigment.

Wings: 1. Most known specimens of Bolshecapnia are macropterous, but at least some individual males of the Iceberg Lake, Montana population of B. spenceri have wings that reach about mid-length of the abdomen and some females of that population have wings that reach almost to the abdominal tip. 2. The R 1 forewing vein is correctly described as “curved upward at origin” by Baumann et al. (1977) in their generic key, however their fig. 295, which purportedly illustrates this character, shows a straight, but anteriorly slanted R1 vein. The same language is used by Stewart & Oswood (2006) in their generic key to regional capniid genera. Their (fig. 3.7), illustrates this character correctly as an anterior curvature of the R1 vein beyond its junction with Rs. The wording of this character and figure used to illustrate it are also in agreement in Stewart & Stark (2008), however the degree of cephalad curvature of the R 1 vein in Bolshecapnia is slightly less than that shown in species of Mesocapnia Raušer, 1968, by Stewart & Stark (2008).

Larval characteristics: Only one Bolshecapnia species, B. spenceri, has been described in the larval phase (Stewart & Stark 1988, 2002, Stewart & Oswood 2006). A key to larvae of the genus is included in Stewart & Stark (1988, 2002, 2008) and in Stewart & Oswood 2006). 1. The cerci of B. spenceri have more than 18 segments and each has an apical whorl of a few moderately long setae, and a few (1-3) short intercalary setae along the outer and inner margins of each cercal segment (Stewart & Oswood 2006). 2. A relatively wide, almost rectangular area is enclosed within the Yarms and the anterior transverse ridge of the mesosternum (Stewart & Oswood 2006).

Recognized species: B. gregsoni, B. milami, B. rogozera, B. spenceri

Distribution: Bolshecapnia species are known from the Rocky Mountains and Pacific Northwest of Alberta, British Columbia, Colorado, Idaho, Montana, New Mexico, Washington, Wyoming and Yukon Territory. No records are currently available from Alaska (DeWalt et al. 2018, Stewart & Oswood 2006).