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Stoneflies - Plecoptera: Perlodidae of Gunnison County, Colorado

Arcynopteryx dichroa (compacta) - Arctic Springfly

(McLachlan) 1872
Updated 11 Aug 2014
TSN 103093


Possibly present at high elevations, 12,000 feet or higher. Look for it!

Locations Collected

Nowhere in the county yet, found in other areas of Colorado.


Older publications may refer to this species as Dictyopteryx compacta. There was considerable confusion about the name of this insect until Teslenko (2012) revised Arcynopteryx and established that Klapálek mis-described this insect as A. compacta which most American scientists accepted until this paper. The executive summary is that A. compacta is restricted to Eurasia, (and was moved to Skwala), so after sorting out a bunch of complications, the Colorado species is now called Arcynopteryx dichroa.

Good Links

On this website:
Key to Perlodidae Nymphs

Other Websites:
Photos, Map, Museum specimens, DNA - Barcodinglife.org


Amore,V; Gaetani,B; Puig,MA and Fochetti,R 2011 New data on the presence of hemocyanin in Plecoptera: Recomposing a puzzle. Journal of Insect Science, 11. HTML

Gehrken,U 1989 Diapause termination in eggs of the stonefly Arcynopteryx compacta(McLachland) in relation to dehydration and cold hardiness. Journal of insect physiology, 35(5), 377-385.
     Abstract: " In the alpine regions of Southern Norway, eggs of the stonefly Arcynopteryx compacta are oviposited in small streams and lake outlets. During ice enclosure, eggs avoid freezing by supercooling and lose about two-thirds of their water content by shrinkage due to osmotic outflux of body water. The eggs enter diapause in autumn at an early stage of embryogenesis. The termination of diapause in 50–55% of eggs kept at 3°C for 3 or 6 months, arises from the effect of chilling on diapause development. The dehydration, however, serves as a diapause-terminating cue. For water contents down to 41%, the termination of diapause seems directly correlated with the degree of dehydration. Treatments with juvenile hormone were also effective in terminating diapause. The termination may therefore be linked to a temporary elevation in juvenile hormone titre by dehydration. Fully hydrated eggs supercool to about -26.5°C, and withstand ice enclosure for 3 days at -22°C. The elevation of supercooling point, water content and depletion of thermal hysteresis-producing proteins correspond with the initiation of postdiapause development. Also ice-enclosure for 3 days at -15 and -18°C proved fatal at this embryonic stage. The loss of cold hardiness could not be related to termination of diapause per se. Eggs remained cold hardy at 3°C as long as the postdiapause development was prevented during the thermally controlled quiescence. The physiological and biochemical mechanisms which underlie adaptation to cold, however, are specific for an early stage of embryogenesis. "

Gehrken,U and Somme,L 1987 Increased cold hardiness in eggs of Arcynopteryx compacta (Plecoptera) by dehydration. Journal of Insect Physiology 33(12) 987–991.
     Abstract: " Eggs of the stonefly, Arcynopteryx compacta, that overwinter in the alpine region of Norwegian mountains, increase their cold-hardiness by dehydration. Eggs enclosed in ice at -22°C survive the loss of about two-thirds of their total water content by shrinkage due to passive diffusion of body water along the concentration gradient. Fully hydrated eggs are killed by freezing at their supercooling point of -26°C, and by direct cooling to -30°C. Dehydrated eggs have a mean supercooling point of -31°C, and survive exposure at -27 and -29°C in ice. Judged from their melting points the eggs do not accumulate low-molecular-weight cryoprotective substances. The difference between freezing and melting points corresponds to a thermal hysteresis of up to 1.8°C. The presence of thermal hysteresis antifreezes may stabilize their supercooled state when enclosed by ice during overwintering. The eggs enter diapause in the autumn, and diapause completion is enhanced both by temperature and time during enclosure in ice. "

Klapálek, Frantisek 1912 Plécoptères. I. Fam. Perlodidae; [monographische Revision. II. Fam. Perlidae; Subfam. Perlinae, Subfam. Neoperlinae; mongraphische Revision] Series Sélys-Longchamps, Edmond de, baron, 1813-1900. Collections zoologiques; catalogue systematique et descriptif, fasc. 4, pt. 1-2.
     According to Teslenko (2012), quote from page 5: "Klapálek designated Arcynopteryx compacta (McLachlan, 1872) as type species of genus Arcynopteryx. However, he was mistaken and misidentified, when provided (Klapálek 1912, fig. 8, page 13) an illustration of "Arcynopteryx compacta McLachlan", which was actually A. dichroa (McLachlan), thus both taxonomic species actually were involved in the misidentification (International Code of Zoological Nomenclature 1999). The type species of Arcynopteryx fixed (under Article 70.3.2 of the Code) as Arcynopteryx dichroa (McLachlan, 1872), misidentified as Arcynopteryx compacta (McLachlan, 1872) in the original designation by Klapálek (1912). "

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 "Historically this holarctic species was only recorded from Morrison, Jefferson Co.,(Ricker, 1952). Recently a robust population was found: Larimer Co., outlet Chasm Lake, Rocky Mountain National Park, 3,650 m, 16July, 1994, B.C. Kondratieff and R.S. Durfee, 5 males, 4 females (CSU); same but 8 Aug 1997, S. Simonson, 4 males, 4 females (CSU)."

McLachlan,R 1872 Notes sur quelques espèces de Phryganides et sur une Chrysopa. Bulletin de la Société Impériale des Naturalistes de Moscou.
     Described as Dictyopteryx compacta.

Shepard, WD. and Stewart KW 1983 Comparative study of nymphal gills in North American stonefly genera and a new, proposed paradigm of Plecoptera gill evolution. Miscellaneous Publications of the Entomological Society of America 13:1-57
     Illustration of nymphal osmobranchiae (gills) on page 52.

Stark,BP and Szczytko,SW 1988. Egg morphology and phylogeny in Arcynopterygini (Plecoptera:
Perlodidae) Journal of the Kansas Entomological Society 61(2) 143-160.First Page
     Abstract: Comparative data are provided for eggs of nine of the eleven recognized genera in the Holarctic tribe, Arcynopterygini, and these data are used to generate a preliminary phylogeny for the group. Four generic clusters (Megarcys/Sopkalia; Frisonia/Perlinodes/Oroperla; Arcynopteryx/Neofilchneria/Skwala and Setvena/Pseudomegarcys) are established primarily from egg data, but resolution of the Frisonia and Arcynopteryx trichotomies required data from other character suites. Detailed illustrations of the epiproct complex are given for six Nearctic genera to provide additional support for the current generic classification of the group and a standardized terminology is proposed for systellognathan Plecoptera eggs.

Stewart,KW; Hassage,RL; Holder,SJ and Oswood,MW 1990 Life cycles of six stonefly species (Plecoptera) in subarctic and arctic Alaska streams. Annals of the Entomological Society of America 83(2)207-214.
     Abstract: Nymphal growth and emergence of adults are described for six species of stoneflies (Plecoptera) found in subarctic and arctic Alaska. The two Nemouridae studied are semivoltine; adults of Zapada haysi (Ricker) are present from May to July and adults of Nemoura arctica Esben-Petersen occur from June to July. The remaining four species are univoltine. Plumiperla diversa (Frison) (Chloroperlidae) has most of its growth occurring during the summer with emergence the following May-September. Taenionema pacificum (Banks) (Taeniopterygidae) completes nymphal growth by the end of January and has an early emergence (April-June). Adults of Arcynopteryx compacta (McLachlan) (Perlodidae) are present from May to August, and growth of nymphs is rapid during summer and fall. Isoperla petersoni Needham ∓ Christenson (Perlodidae) adults are present from June to mid-August, and nymphal growth is interrupted by winter and resumes in the spring; the three other univoltine species studied tend to complete growth before the onset of winter. Growth of these six species is tied to seasonal temperature variation.

Stewart,KW and Stark,BP 2002 Nymphs of North American Stonefly Genera. 2nd edition The Caddis Press, Columbus, Ohio. 510 pages.
     Illustration of nymph on page 365 figure 14.1.

Teslenko,VA 2012 A taxonomic revision of the genus Arcynopteryx Klapálek, 1904 (Plecoptera, Perlodidae). Zootaxa, 3329, 1-18.
     At the end of this paper the author redescribes Arcynopteryx compacta as Skwala compacta. Abstract: " Four known Arcynopteryx species are redescribed from the types and newly acquired material. Illustrations of the male and female genitalia, head and pronotal patterns and eggs are used to support species descriptions. Dictyopteryx compacta (McLachlan, 1872) is transferred to Skwala Ricker, 1943 with the valid name Skwala compacta (McLachlan, 1872) comb. nov., and S. pusilla (Klapálek, 1912) is placed as a junior synonym of that species. For genus Arcynopteryx type species is fixed (under Article 70.3 of the Code) as Arcynopteryx dichroa (McLachlan, 1872), misidentified as Arcynopteryx compacta (McLachlan, 1872) in the original designation by Klapálek (1912). "

Theissinger,K; Feldheim,KA; Seitz,A and Pauls,SU 2009 Isolation and characterization of 11 polymorphic trinucleotide microsatellite markers in the stonefly Arcynopteryx compacta (Plecoptera: Perlodidae) Molecular Ecology Resources 9(1)357-359.
     Abstract: We describe the isolation of eleven polymorphic trinucleotide microsatellite loci from the stonefly Arcynopteryx compacta. Loci were highly variable with 3 to 14 alleles (mean = 6.45). Observed heterozygosity ranged from 0 to 0.867. Seven loci showed significant deviation from Hardy–Weinberg equilibrium across both populations. There was no evidence for null alleles, and thus, Hardy–Weinberg departures could have resulted from genetic structure between populations or subpopulations. No linkage between loci was found. The eleven loci should prove highly informative for population genetic studies.


Mesosternal Y-arms.
Only visible easily on mature nymphs.


Notice there are no serrations on the edges of the mandibles teeth. Compare to Skwala.

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