Giant Snowfly - Isocapnia grandis
Species within the Capniidae are small winter stoneflies. This family is one of the largest families in the order Plecoptera, containing some 300 species distributed throughout the Holarctic region, 25 species occur in Montana. As their name implies these species are generally cold-water stenotherms and hatch in late-winter through early spring. The adults emerging in the winter are often found walking around on the snow. Their closest relatives are the rolled-winged stoneflies (Leuctridae). Many species are endemic to small ranges, perhaps due to the family's tendency to evolve tolerance for cold (isolating populations in mountain valleys) and winglessness (inhibiting dispersal).
Observations in Montana Natural Heritage Program Database
Number of Observations:
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(Observations spanning multiple months or years are excluded from time charts)
Very little information exists about the ecology of this species (Baumann, Gaufin, and Surdick 1977). Merritt and Cummins (1996) report that members of the genus Isocapnia are found in both creeks and river, and are trophically shredder-detritivores.
Merritt and Cummins (1996) report that members of this family are trophically shredder-detritivores; eating large particulate organic materials such as detritus, leaves and plants.
Probably cold water stenotherms
- Literature Cited AboveLegend: View Online Publication
- Baumann, R.W, A.R. Gaufin, and R.F. Surdick. 1977. The stoneflies (Plecoptera) of the Rocky Mountains. American Entomological Society, Philadelphia.
- Cummins, K.W. and R.W. Merritt. 1996. Ecology and distribution of aquatic insects. Chapter 6, pages 74-86 in R.W. Merritt and K.W. Cummins (eds.) An Introduction to the Aquatic Insects of North America. Third Edition. Kendall/Hunt Publishing Company, Dubuque, Iowa. 862 pp.
- Additional Sources of Information Related to "Insects"