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Stoneflies - Plecoptera: Chloroperlidae of Gunnison County, Colorado

Sweltsa coloradensis - Colorado Sallfly

(Banks 1898)
Updated 22 December 2023
TSN 103283


Older publications may refer to this species as Chloroperla coloradensis or Alloperla coloradensis.

Good Links

On this website:
Introduction to Sweltsa

Other Websites:
Species details from plecoptera.species.file

Photos, Map, Museum, DNA - Barcodinglife.org

  • Photos -by Riley Nelson from the Tree of Life
         Nymph slide 35
         Another Nymph slide 36>
         Adult Slide 5


    Banks,N 1898 Descriptions of new North American neuropteroid insects. Transactions of the American Entomological Society 25:199-218.
         Original description of S. coloradensis as Chloroperla coloradensis.

    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
         Quote from page 178: "This species is common in creeks and small rivers throughout its range. The adults emerge from April through August. "

    DeWalt,RE; Stewart,KW; Moulton,SR; Kennedy,JH 1994 Summer emergence of mayflies, stoneflies, and caddisflies from a Colorado mountain stream. Southwestern Naturalist 39 (3) 249-256. First page

    Hassage,RL 1989 Life histories, behavior and space partitioning in selected species of western North American Plecoptera. pHd Dissertation, University of North Texas. 105pgs. PDF
         Abstract: "Five species of stoneflies (Zapada haysi, Plumiperla diversa, Taenionema pacificum, Isoperla petersoni, Arcynopteryx compacta) from the North Slope and Interior of Alaska were examined for seasonal patterns of emergence of adults and growth of nymphs. Generally growth was retarded during the winter in this region, and all species except I. petersoni completed growth prior to January. The life cycles of six stonefly species (Prostoia besametsa, Triznaka signata, Sweltsa coloradensis, Isoperla fulva, Skwala parallela, Claassenia sabulosa) are described from northern New Mexico. In this region growth was generally less retarded during the winter than in Alaska; P. besametsa completed all nymphal growth during late fall and winter. Drumming behavior of a Colorado population of Pteronarcella badia was described using an evolutionary framework to explain the maintenance of signal variation in this species. Laboratory experiments were used to explore the effect of intraspecific and interspecific interactions on spatial partitioning in P. badia and Claassenia sabulosa. P. badia exhibited clumping and distributed itself as the surface area of substrate in low densities; however, in the presence of C. sabulosa its distribution was random and different from available surface area. A field study was used to examine spatial partitioning by three New Mexico stonefly species (I. fulva, P. besametsa, T. signata) and to ascertain patterns of microdistribution relating to several abiotic and biotic factors. Generally, there was an interaction of the measured abiotic parameters (current, water temperature, time) with nymphal size. Additionally, void space and sample volume were successfully used to compare biotic densities among leaf and mineral substrates, which were higher in leaf packs than in mineral substrates."

    Kiffney,PM; Clements,WH 1994 Effects of heavy metals on a macroinvertebrate assemblage from a Rocky Mountain stream in experimental microcosms. Journal of the North American Benthological Society 13 (4) 511-523.

    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 394. "This common and widespread Western North American species can be abundant in many Montane and Plateau streams, including larger streams between 1,600m and 2,500m."

    Malison,RL; Ellis,BK; DelVecchia,AG; Jacobson,H; Hand,BK; Luikart,G; Woods,HA; Gamboa,M; Watanabe,K and Stanford,JA 2020 Remarkable anoxia tolerance by stoneflies from a floodplain aquifer. Ecology, 101(10), p.e03127. PDF
         Abstract: "Alluvial aquifers are key components of river floodplains and biodiversity worldwide, but they contain extreme environmental conditions and have limited sources of carbon for sustaining food webs. Despite this, they support abundant populations of aquifer stoneflies that have large proportions of their biomass carbon derived from methane. Methane is typically produced in freshwater ecosystems in anoxic conditions, while stoneflies (Order: Plecoptera) are thought to require highly oxygenated water. The potential importance of methane-derived food resources raises the possibility that stonefly consumers have evolved anoxia-resistant behaviors and physiologies. Here we tested the anoxic and hypoxic responses of 2,445 stonefly individuals in three aquifer species and nine benthic species. We conducted experimental trials in which we reduced oxygen levels, documented locomotor activity, and measured survival rates. Compared to surface-dwelling benthic relatives, stoneflies from the alluvial aquifer on the Flathead River (Montana) performed better in hypoxic and anoxic conditions. Aquifer species sustained the ability to walk after 4-76 h of anoxia vs. 1 h for benthic species and survived on average three times longer than their benthic counterparts. Aquifer stoneflies also sustained aerobic respiration down to much lower levels of ambient oxygen. We show that aquifer taxa have gene sequences for hemocyanin, an oxygen transport respiratory protein, representing a possible mechanism for surviving low oxygen. This remarkable ability to perform well in low-oxygen conditions is unique within the entire order of stoneflies (Plecoptera) and uncommon in other freshwater invertebrates. These results show that aquifer stoneflies can exploit rich carbon resources available in anoxic zones, which may explain their extraordinarily high abundance in gravel-bed floodplain aquifers. These stoneflies are part of a novel food web contributing biodiversity to river floodplains."

    Malison,RL; Hand,BK; Winter,E; Giersch,JJ; Amish,SJ; Whited,D; Stanford,JA and Luikart,G 2022 Landscape connectivity and genetic structure in a mainstem and a tributary stonefly (Plecoptera) species using a novel reference genome. Journal of Heredity, 113(4), pp.453-471.
         Abstract: "Understanding how environmental variation influences population genetic structure can help predict how environmental change influences population connectivity, genetic diversity, and evolutionary potential. We used riverscape genomics modeling to investigate how climatic and habitat variables relate to patterns of genetic variation in 2 stonefly species, one from mainstem river habitats (Sweltsa coloradensis) and one from tributaries (Sweltsa fidelis) in 40 sites in northwest Montana, USA. We produced a draft genome assembly for S. coloradensis (N50 = 0.251 Mbp, BUSCO > 95% using "insecta_ob9" reference genes). We genotyped 1930 SNPs in 372 individuals for S. coloradensis and 520 SNPs in 153 individuals for S. fidelis. We found higher genetic diversity for S. coloradensis compared to S. fidelis, but nearly identical genetic differentiation among sites within each species (both had global loci median FST = 0.000), despite differences in stream network location. For landscape genomics and testing for selection, we produced a less stringently filtered data set (3454 and 1070 SNPs for S. coloradensis and S. fidelis, respectively). Environmental variables (mean summer precipitation, slope, aspect, mean June stream temperature, land cover type) were correlated with 19 putative adaptive loci for S. coloradensis, but there was only one putative adaptive locus for S. fidelis (correlated with aspect). Interestingly, we also detected potential hybridization between multiple Sweltsa species which has never been previously detected. Studies like ours, that test for adaptive variation in multiple related species are needed to help assess landscape connectivity and the vulnerability of populations and communities to environmental change."

    Nelson,SM and Roline,RA 1999 Relationships between metals and hyporheic invertebrate community structure in a river recovering from metals contamination. Hydrobiologia 397, 211-226.
         They found Sweltsa pr. coloradensis primarily in the hyporheic samples. The mean density in the surface samples was 2000 animals/meter² while in the hyporheic zone there was a mean of 13,744 animals/meter².

    Newell,RL; Baumann,RW and Stanford,JA 2008 Stoneflies of Glacier National Park and Flathead River basin, Montana. International Advances in the ecology, zoogeography, and systematics of mayflies and stoneflies. University of California Publications in Entomology, Berkeley and Los Angeles, pp.173-186.
         The authors note that S. coloradensis was the 2nd most frequently recorded species out of the 100 different stonefly taxa they collected in their survey of Glacier National park and the Flathead basin in northwestern Montana.

    Stark,BP and Baumann,RW 2018 Two New Stonefly Species in the Sweltsa coloradensis (Banks) Complex (Plecoptera: Chloroperlidae). Illiesia, 14(02):30-43. https://doi.org/10.25031/2018/14.02 PDF
         Abstract: "Male reproductive structures were examined with scanning electron microscopy for populations of the Sweltsa coloradensis (Banks) complex from throughout the known range in western North America. Sufficient variation was observed in epiproct structure to recognize and describe two new species. Sweltsa mogollonica, n. sp. is recognized from eastern Arizona and western New Mexico and S. lyrata, n. sp. is recognized from Alberta, British Columbia, Idaho, Montana, Washington and Yukon Territory."
    [Among many electron microscope images is one of a specimen from Quartz creek in Gunnison County, CO]

    Stewart,KW and Stark,BP 2002 Nymphs of North American Stonefly Genera. 2nd edition The Caddis Press, Columbus, Ohio. 510 pages.
         Photo of nymph with clearly visible abdominal stripe on page 105 figure 6.8

    Surdick,RF 1985 Nearctic Genera of Chloroperlinae (Plecoptera: Chloroperlidae). University of Illinois Press, Urbana, IL. 146 pages.

    Surdick,RF 1995 New western nearctic Sweltsa (Plecoptera: Chloroperlidae). Proceedings of the Entomological Society of Washington 97 1, 161-177.

    Brown, WS 2004 Plecoptera or Stoneflies of Gunnison County, Colorado