Stoneflies - Plecoptera: Nemouridae of Gunnison County, ColoradoZapada frigida - Frigid Forestfly(Claassen) 1923Updated 12 January 2026
TSN 102601 
The animal on the left is a Zapada haysi/oregonensis group and the animal on the right is Z. frigida. Notice the long thin cervical gills on the Z. frigida nymph. NotesThis animal is present in Splains Gulch and the Coal Creek drainage. Also, look for Z. frigida at higher elevations and in smaller spring fed creeks. The genus Zapada was previously named Nemoura. Older publications may refer to this species as Nemoura frigida.Good LinksOn this website:Introduction to Zapada Other Websites: Photos, Map, Taxon Identifier Numbers - from the Global Biodiversity Information Facility Zapada frigida at GBIF Photos, Map, Museums, DNA - Barcode of Life Data System Photo - Nymph from Michael Wigle Photography. Look at the cervical gills, which appear as white filaments under the neck. ReferencesBaumann,RW 1973 Studies on Utah stoneflies (Plecoptera). The Great Basin Naturalist, pp.91-108.Quote from page 92: "Zapada frigida is never abundant but has a scattered distribution throughout most of the western states. A single male from the Manti-La Sal National Forest is the first Utah record: Johnson Creek, 19 miles N Blanding, Abajo Mountains, San Juan Co., 18-VI-1946, S. B. Muliak (NMNH)." Baumann,RW; Gaufin,AR and Surdick,RF 1977: The stoneflies (Plecoptera) of the Rocky Mountains. Memoirs of the American Entomological Society 31, 1-208. PDF In the keys, adult wings are uniformly brown, Other Zapada species have mottled wings. Adult males, females and larvae all have cervical gills (gills on their neck) which are 12-15 times as long as wide. This is in contrast to Z. oregonensis group and Z. haysi larvae which have 4 simple gills that are less than 10 times as long as wide. Quote from page 46: "The nymphs are usually found in small headwater streams and spring fed creeks. This species is found primarily in the northwest but is never common. The adults emerge from March to August." Bottorff,RL and Bottorff,LD 2007 Phenology and diversity of adult stoneflies (Plecoptera) of a small coastal stream, California. Illiesia 3(1):1-9 PDF 292 Kb Chen,ZT 2022 Zapada (Plecoptera: Nemouridae), a stonefly genus new to the fauna of China. Zootaxa, 5115(4), pp.559-570. Abstract: "A new species of Zapada Ricker, 1952, Zapada kondratieffi sp. nov. from central Sichuan Province of China is described and illustrated, which represents the first record of the genus in China. The new species is characterized mainly by the presence of five simple cervical gills, vestigial inner paraproct lobe, and absence of paraproct spines. The preliminary molecular phylogenetic analysis using COI sequences recovered the relationship among eight species of Zapada and supports the close relationship between Z. kondratieffi and Zapada frigida (Claassen, 1923)." Claassen,PW 1923 New species of North American Plecoptera. Canadian Entomologist 55, 257-263,281-292. Described as Nemoura frigida. Jones,TS and Resh,VH 1988 Movements of adult aquatic insects along a Montana (USA) springbrook. Aquatic insects, 10(2), 99-104. PDF Abstract: " The occurrence and movement patterns of adult insects along a forested springbrook near Flathead Lake, Montana, USA, were studied during three 15-day periods from 19 June through 9 August 1985, using a two-sided Malaise trap. Of the Plecoptera, numbers of males and gravid females of Malenka flexura gravid females of Zapada frigida and total numbers of Paraperla wilsoni were significantly higher for downstream-flying adults during one to three periods. Of the Trichoptera, numbers of males of Anagepetus debilis were significantly higher for upstream flying adults during one period, and males of Lepidostoma cascadense and gravid females of L. spicata were significantly higher for downstream-flying adults during another period. In none of the 26 species examined in these three orders did females show a statistically significant pattern of upstream flight." Kondratieff,BC and Baumann,RW 2002 A review of the stoneflies of Colorado with description of a new species of Capnia (Plecoptera: Capniidae). Transactions of American Entomological Society 128 (3) 385-401. Quote from page 392: "Zapada frigida is a common species of the Pacific Northwest, but has only been collected in Boulder, Hinsdale, Summit and Grand counties, from several areas of the high mountain region. " McKnight,DM and Feder,GL 1984 The ecological effect of acid conditions and precipitation of hydrous metal oxides in a Rocky Mountain stream. Hydrobiologia, 119, pp.129-138. PDF Needham,JG and Claassen,PW 1925 A Monograph of the Plecoptera of North America. Entomological Society of America, Lafayette, Indiana. 397 pages. PDF Discussed as Nemoura frigida.  
Stark,BP; Oblad,BR and Gaufin,AR 1973 An annotated list of the Stoneflies (Plecoptera) of Colorado Part I. Entomological News 84 9, 269-277. Zuellig,RE; Heinold,BD; Kondratieff,BC and Ruiter,DE 2012 Diversity and Distribution of Mayflies (Ephemeroptera), Stoneflies (Plecoptera), and Caddisflies (Trichoptera) of the South Platte River Basin, Colorado, Nebraska, and Wyoming, 1873-2010. U.S. Geological Survey Data Series 606, 257 p. PDF - caution 46MB Quote from page 51: "Zapada frigida is a more Pacific Northwest stonefly that is rarely collected in the SPRB (Kondratieff and Baumann, 2002)."The elevation range is 10,850-11,200 feet and the adults were found from June-July. |