Vol. 114. No. 5. November& December2003 289 SCIENTIFIC NOTE CONFIRMATION OF THE PYGMY SNOWFLY, ALLOCAPNIA PYGMAEA (BURMEISTER) (PLECOPTERA: CAPNIIDAE), FROM NORTH DAKOTA, UNITED STATES' B.C.Kondratieff and R.W. Baumann' Kondratieffand Baumann (1999) listed fifteen stoneflytaxa, including eleven confirmed species for North Dakota. Included only as a genus record was the snowfly genusAllocapnia based on nymphs. We predicted that based on known distributional proximity, themost likely species ofAllocapnia occurringinNorth Dakota would beA. pygmaea (Burmeister). Recently, a vial ofAllocapnia spec- imens was brought to ourattention by eminent coleopterist Robert D. Gordon at the National Museum ofNatural History. He collected these stoneflies from a small stream in southeasternNorth Dakota, SargentCounty. These specimens in- cluded four adult males ofA.pygmaea allowing species confirmation. This sub- boreal species occurs in a transverse band across the northern United States and southern Canada, south to Tennessee, with disjunct populations in the Ozark Mountains of Missouri (Ross et al. 1967, Ross and Ricker 1971, Poulton and Stewart 1991). Allocapnia is considered an eastern deciduous forest associated group of stoneflies (Ross and Ricker 1971), and presently includes 43 species (Kondratieffand Kirchner 2000). Ross et al. (1967) postulated that during the Wisconsin glacial maximum, A.pygmaea occurred south ofthe ice sheets inthe Cumberland Plateauregionof east central United States. Dispersal northward and westward ofthis species oc- curred during the post-Wisconsinan times, into deglaciated regions, following a northern route overthe Great Lakes (see Ross et al. 1967, Fig. 2).An alternative hypothesis proposes that these North Dakota populations are remnants ofnorth- ern dispersals from the Missouri Ozark populations. However, the North Dakota males are clearly most similar to northeastern populations and not to the males described by Ross etal. (1967) from Missouri. The Minnesota records ofA.pyg- maea are from areas along Lake Superiorand south ofMinneapolis next to near- by Michigan (Ross and Ricker 1971, Lageret al. 1979). Recently, Heimdal et al. (2004) reported A. pygmaea from northeastern Iowa. It then appears that the southeastern North Dakota populations of this species clearly fit the dispersal pattern proposed by Ross et al. (1967), and have originated from a single source. 'Receivedon February 14,2004.AcceptedonJuly 16,2004. 1Department of Bioagricultural Sciences and Pest Management. Colorado State University, Fort Collins,Colorado80523 U.S.A. E-mail: Boris.Kondratieff( colostate.edu. 'Department ofIntegrative Biology, Monte L. Bean Life Science Museum, Brigham Young Uni- versity, Provo, Utah 84602 U.S.A. E-mail: Richard_Bautnann( byu.edu. Mailedon September30, 2004 290 ENTOMOLOGICALNEWS The Sargent County record represents the most western record for Allocapnia and outside the eastern deciduous forest biome. NW MaterialExamined:NorthDakota:SargentCo.,SouthofCayuga,7miles ofVerblen,South Dakota,21 March 1966, R. D. Gordon,AarhusandTweten,4males, 1 female, 7 nymphs (National MuseumofNatural History, Entomology,Washington, DistrictofColumbia, U.S.A.). ACKNOWLEDGEMENTS Wethank Dr. RobertGordon forencouraging usto look forthese specimens at the Smithsonian Institution. Dr. OliverS. Flint,Jr. facilitated theloanthatledtothispaper. LITERATURE CITED IItinuhil. D. P., R. E. DeWalt, and T. F. Wilton. 2004. An annotated checklist ofthe stoneflies (Plecoptera)ofIowa. Proceedingsofthe Entomological SocietyofWashington(Inpress). Kondratieff, B. C. and R. W. Baumann. 1999. Studies on stoneflies ofNorth Dakota with the description ofa new Perlesta species (Plecoptera: Perlidae). Proceedings ofthe Entomological SocietyofWashington 101: 325-331. Kondratieff, B. C. and R. F. Kirchner. 2000. Two newAllocapnia from eastern North America (Plecoptera: Capniidae).Annalsofthe Entomological SocietyofAmerica93: 1267-1273. Lager,T. IM., M. D.Johnson, S. N. Williams, and J. L. McCulloch. 1979. Apreliminaryreport onthePlecopteraandTrichopteraofNortheasternMinnesota.GreatLakesEntomologist 12: 109- 114. Poulton,B.C.andK.W.Stewart. 1991. ThestonefliesoftheOzarkandOuachitaMountains(Ple- coptera). MemoirsoftheAmericanEntomological Society38. 116pp. Ross,H.H.,G.L.Rotramel,J.E.H.Martin,andJ.F.McAlpine. 1967. Postglacialcolonization ofCanadabyitssubborealwinterstonefliesofthegenusAllocapnia. CanadianEntomologist99: 703-712. Ross, H. H. and W. E. Ricker. 1971. The classification, evolution, and dispersal ofthe winter stoneflygenusAllocapnia. IllinoisBiological Monograph45. 106pp.