Quedius plagiatus Mannerheim, 1843: 231

Brunke, A. J., Salnitska, M., Hansen, A. K., Zmudzinska, A., Smetana, A., Buffam, J. & Solodovnikov, A., 2020, Are subcortical rove beetles truly Holarctic? An integrative taxonomic revision of north temperate Quedionuchus (Coleoptera: Staphylinidae: Staphylininae), Organisms Diversity & Evolution (New York, N. Y.) 20 (1), pp. 77-116 : 106-109

Quedius plagiatus Mannerheim, 1843: 231

Quedius (Quedionuchus) longipennis Mannerheim (misidentification of Q. plagiatus ): Smetana 1965 (Newfoundland, as separate species from ‘ Q. laevigatus ’)

Quedius (Quedionuchus) laevigatus (in part): Smetana 1971 (North America, treated both Q. longipennis and Q. plagiatus in present sense, as single species under unavailable name laevigatus Gyllenhal ; lectotype designation for Quedionuchus plagiatus )

Quedius (Quedionuchus) plagiatus Mannerheim 1843 (in part): Smetana 1990 ( Q. longipennis and Q. plagiatus in present sense, as single species under available name plagiatus Mannerheim )

Quedionuchus plagiatus ( Mannerheim 1843) (in part): Brunke and Solodovnikov 2013 ( Quedionuchus as valid genus)

Type locality: Sitka , Alaska, USA .

Type material. Lectotype: (female, MCZ): [grey locality disc]/Type 8251 [red label]/2. plagiatus, Sitka Mann. [handwritten label]/ Aug–Dec 2004, MCZ image database/MCZ- ENT 00008251 [barcode label].

The female lectotype, from Sitka , Alaska , designated by Smetana (1971) matches the concept given here for a species of the Glaber group that has sparse abdominal microsculpture and has a broad lobe of female tergite X. Quedionuchus gilaensis is very similar but occurs only in Arizona and New Mexico.

Other material.

CANADA: Alberta: 5mi S.W. of Strachan, 52.2076 – 115.217, 20.IX.1967, under bark; P. contorta, A.G. Raske & B.M. Dahl (1, CNC); same except 12-16.IX.1967 (4, CNC); same except 20-22.IX.1961 (2, CNC); Banff, 51.1774 – 115.571, Klimsch (1, FMNH); Boom Lake, 51.2643 – 116.106, 1828 m, 16.VII.1971, J.M. & B.A. Campbell (1, CNC); Cameron Lake, Waterton Lakes National Park, 49.0074–114.05, 1676 m, 28.VII.1980, D.E. Bright (1, CNC); same except 12.VI.1956, O. Peck (1, CNC); Canmore, 51.0888 –115.362, 10.VI.1956, B.F. & J.L. Carr (4, CNC); Coleman, 49.635 –114.503, 1.VII.1981, B.F. & J.L. Carr (2, CNC); Consolation Lake, Banff National Park, 51.3095–116.15, 1950-2133 m, 15.VI.1968, Campbell & Smetana (3, CNC); Crypt Lake, Waterton Lakes National Park, 49.0015 –113.841, 1981 m, 22.VI.1980, J.M. Campbell (1, CNC); Edmonton, 53.5449–113.49, 24.viii.1917, F. S. Carr (1, FMNH); Eisenhower Junction, Banff National Park, 51.3273 –115.966, 26.VII.1966, Engelman spruce, A. Raske, (1, CNC); Jasper Park, 52.8734 –117.954, VIII.1922, Pinus contorta, J. M. Swaine , (1, CNC); km 9 of Chief Mountain Highway, Waterton Lakes National Park, 49.0554 –113.718, 1371 m, 10.VII.1980, H.J. Teskey (1, CNC); Lake Louise, 51.4254 –116.177, 18.VII.1918 (1, CNC); Lake Louise, Banff National Park, 51.4254 – 116.177, 2042 m, 18.VII.1955, W.J. Brown (1, CNC); Peyto Lake, between main road and overlook, 51.72–116.52, 2000 m, 6.IX.1978, under stones, low bushes and grass, A.V. Morgan (1, DEBU); Rowe Lakes Trail, Waterton Lakes National Park, 49.0833 – 113.917, 1828 m, 27.VI.1980, J. M. Campbell (1, CNC); Sibbald Flats Recreation Area, 51.0436 –114.864, 11- 15.V.1984, lodgepole pine/aspen forest, R. Anderson (1, CNC); Summit Lake Trail, Waterton Lakes National Park, 49.0072 –114.025, 18.VII.1980, D.E. Bright (1, CNC); Swan Hills, Goose Mtn. , 55.4333–115.3, 1356 m, 31.VII.1977, un- der bark of Pinus, J.S. Ashe (7, SEMC); Township 28, Range 6, West of 5th Meridian, 51.3833–114.75, 14.V.1978, B.F. & J.L. Carr (1, CNC); Township 34, Range 7, West of 5th Meridian, 51.8969 –114.969, 13.VII.1980, B.F. & J.L. Carr (1, CNC); Township 4, Range 3, West of 5th Meridian, Section 34, 49.3428 –114.325, 15.V.1987, B.F. & J.L. Carr (1, CNC); Waiparous, 51.2828–114.84, 22.VIII.1954, B.F. & J.L. Carr (1, CNC); Waterton Lakes National Park, Bertha Falls, 49.0828 –113.919, 29.VII.1980, Abies lasiocarpa, D. Bright (1, CNC); British Columbia: 15mi E of Barkerville, Two Sisters Mountain, 53.204 –121.546, 1676 m, 24.VI.1968, Campbell & Smetana (9, CNC); 15mi North of Barkerville, Two Sisters Mountain, 53.204 –121.546, 1676 m, 24.VI.1968, Campbell & Smetana (1, CNC); 28mi E. of Sicamous, 50.7818 –118.326, 18.VI.1968, ex river debris, Campbell & Smetana (1, CNC); Aspen Grove, 49.9303–120.63, 7.V.1934, under bark, Pinus ponderosa, H.B. Leech (1, CNC); Atlin, 59.578–133.69, 670 m, 7.VI.1955, H. Huckel (1, CNC); Berg Lake Trailhead, Mount Robson Provincial Park, 53.0647 –119.203, 11-29.VIII.1984, flight interception trap, Cedar/hemlock, R. S. Anderson (1, CNC); Bouleau Lake, 50.2866 –119.655, 27.V.1956, Releech (4, CNC); Calvert Island, trail from headquarters to West Beach, 51.656 –128.135, 18.VI.2018, Lindgren Funnel, coniferous forest, M. Pentinsaari, (2, BIO); Cheakamus Lake, Garibaldi Provincial Park, 50.0142–122.92, 914 m, 20.VII.1973, A. & Z. & D. Smetana (1, CNC); Eva Lake, Mount Revelstoke National Park, 51.0815 -118.108, 25.VII.1971, J.M. & B.A. Campbell (1, CNC); Glacier National Park, 5.6mi E of E. Boulder on Hwy 1, 51.3428 –117.477, 11-15.VI.1984, flight interception trap, R. S. Anderson (1, CNC); Goldstream Park, 5mi N. of victoria, 48.4843 –123.549, 27.V.1968, Campbell & Smetana (1, CNC); Goldstream Provincial Park, 48.4843 – 123.549, 6.VII.1975, J.M. & B.A. Campbell (1, CNC); Inverness, 54.1987 –130.258, VII.1910, J.H. Keen (4, CNC); Kaslo, 49.9142 –116.915, 7.VIII.1964, B.F. & J.L. Carr (1, CNC); same except 8.VIII.1964, (1, CNC); same except 7.VII.19 64 (1, CNC); Kelsey Bay, 50.39 – 125.96, 17.VI.1988, pheromone trap, log staging area, mixed forest, J. Pilny (6, DEBU); same except 18.VI.1988 (10, DEBU); Lake McArthur, Yoho National Park, 51.3326 –116.338, 2133 m, 28.VII.1971, J.M. & B.A. Campbell (1, CNC); Liard River, Hot Springs, 59.4231 –126.098, 8.VII.1981, Picea sp. D .E. Bright (2, CNC); same except 2.VI.1981 (1, CNC); Masset, 54.0126 –132.141 (1, CNC); Mile 11 Mount Revelstoke Highway, 50.9952 –118.196, 1463 m, 18.VI.1986, Campbell & Smetana (1, CNC); Mile 180 Alaska Highway, 57.5021 –122.927, 28.VI.1955, B.F. & J.L. Carr (1, CNC); Mile 49 Alaska Highway, 56.2619–120.92, 30.VI.1955, B.F. & J.L. Carr (2, CNC); Mt. Cain, 50.24 -126.40, Lindgren funnel, 5–18.VIII.1997, N. Winchester (1, LFC); same except 13.VII.1996 (1, LFC); same except 20.VII.–5.VIII.1997 (1, LFC); Mt. Seymour, Vancouver, 49.3933 – 122.944, 2.vii.1973, N. M. Downie (1, FMNH); Nicola Ranges, 50.1637 –120.671, 7.viii.1932, G.J.S. (2, FMNH); Peachland, 49.7699 –119.742, 9.VIII.1919, J.B. Wailis (1, CNC); same except 15.VII.1912 (1, CNC); Sinclair Creek, Kootenay National Park, 50.628 –116.071, 1524 m, 12.VI.1968, Campbell & Smetana (7, CNC); same except 11.VI.1968, Campbell & Smetana (5, CNC); Vermilion Pass, 51.2275–116.05, 13.VI.1954, B.F. & J.L. Carr (3, CNC); same except 3.VI.1954 (1, CNC); same except 3.VI.1953 (3, CNC); Whistler Mountain, Garibaldi Provincial Park, 50.0591 –122.957, 1828 m, 24.VII.1973, A & Z & D Smetana (2, CNC); Yoho Park, 51.4667 –116.583, 28.VIII.1953, B.F. & J.L. Carr (1, CNC); same except 20.VIII.1953 (1, CNC); Newfoundland and Labrador: Doctors Brook, 50.77–57.07, 31.VII.1949, Lindroth (1, CNC); Gros Morne National Park, James Callaghan Trail, 49.5686 –57.8302, 39 m, 30.VII.2013, Malaise, mature conifer stand, wind damage, R. Reid, (1, BIO); Labrador, near Port Hope, Simpson, 52.817 –56.333, 103 m, 28.VI.2009, D. Langor, S. Pardy (1, NFC); Ontario: Gargantua, Lake Superior Provincial Park, 47.5696 –84.9731, 7.VI.1973, J.M. Campbell & R. Parry (1, CNC); Quebec: Gaspé, 48.87– 64.68, 29.VI.1933 (1, FMNH); Jupiter River, Anticosti Island, Minganie, 49.516–63.35, 20-27.VII.1993, Hébert & Jobin, Lindgren Funnel, Sapinière (2, LFC); Lac Anna, Anticosti island, Minganie County, 49.866 –64.116, 6- 14.VII.1993, Lindgren trap, Pessière Blanche, 70ans, Hébert & Jobin (1, LFC); same except 29.VI.-6.VII.1993, Pessière Blanche, 70ans (1, LFC); Lac Mitis, 48.3–67.8, Lindgren-2, Dispositif B, Sapiniere, Hebert & Jobin (1, LFC); Lac Poissonneux, 47.05–72.133, 29.VI.-6.VII.1999, Bétulaie Jaune à Sapin (1, LFC); McDonald River, Anticosti Island, Minganie, 49.75–63.083, 4-10.VIII.1993, Lindgren Funnel, Sapiniere mature, Hébert & Jobin (2, LFC); same except 27.VI.-4.VII.1993 (1, LFC); Minganie, Anticosti Island, Lake Anna, 49.866 –64.116, 29.VI.-6.VII.1993, Lindgren Funnel, Pessière Blanche, 70ans, Hébert & Jobin (1, LFC); Mitis Lake, 48.3–67.8, 26-28.VII.1993, Lindgren-4, Sapiniere, Hébert & Jobin (1, LFC); Montmorency Forest, Montmorency County, 47.26–71.16, 19-26.VII.1999, Piège à impact, Sapinière, C. Hébert (6, LFC); same except 16- 19.VII.1999 (1, LFC); same except 15.VII.1999 (1, LFC); same except 15-19.VII.1999 (3, LFC); same except 16- 20.VII.1999 (1, LFC); Rivière à la loutre, Ile Anticosti, Minganie, 49.783 –63.683, 20-27.VII.1993, Piège Lindgren, Sapinière mature, 80 ans, Hébert & Jobin (1, LFC); Yukon: Dempster Highway mi 32, 60.6073 –134.944, 822 m, 15.VII.1968, Campbell & Smetana (1, CNC); Kluane National Park and Reserve, Auriol Trail, 60.714 –137.432, 798 m, 26.V.2014, Malaise, spruce forest, C. Wong and D. Blakeburn (1, BIO); same except 24.VII.2014, Malaise, spruce and aspen forest, BIObus 2014 (1, BIO); same except 2.VII.2014, spruce forest (1, BIO); Km 1192 Alaska Highway, 60.0224 –132.214, 6.VIII.1987, B.F. & J.L. Carr (1, CNC); Km 72 Dempster Highway, 64.5059 –138.221, 21.VI.1981, Picea glauca, D.E. Bright (1, CNC); km 72 of Dempster Highway, 64.5059 –138.221, 20.VI.1981, under stones, D.E. Bright (1, CNC); same except 21.VI.1981, D.E. Bright (1, CNC); Mile 45 of Dempster Highway, 64.5032 – 138.219, 1.VII.1979, B.F. & J.L. Carr (3, CNC); Mile 635 Alaska Highway, 60.1449 –129.617, 11.VII.1955, B.F. & J.L. Carr (1, CNC); Snag, 62.3992 –140.372, 24.VI.1948, Picea glauca, Jason & Hughes (1, CNC); Swim Lakes, 62.1913 132.885, 975 m, 18.VI.1960, J.E.H. Martin (3, CNC); same except 13.VI.1960, on Picea W.J. Brown (1, CNC); same except 13.VI.1960, J.E.H. Martin (1, CNC); Vangora Creek, 62.25–133.25, 1066 m, 12.VI.1960, J.E.H. Martin (1, CNC).

USA: Alaska: Byers Lake Campground, Denali State Park, 62.7442 –150.126, 26.VI.1978, Smetana & Becker (2, CNC); Denali National Park, 63.6426 –149.572, 833 m, 17.VIII.2016, 10-min ground search, spruce, Adam Haberski (1, UAM); same except 18.VII.2018 (1, UAM); Fairbanks, 930 Fitz CT, 64.901 –147.528, 280-293 m, 1.VI.2013, yard, cut spruce, D.S. Sikes (1, UAM); same except 1-2.VI.2013 (1, UAM); Homer, 59.65–151.56, 4.VIII.1988, under Picea bark, Picea forest, Pilny (2, DEBU); Kenai Pen., Summit area, [Chugach N.F.], 60.6667–149.5, 300-1200 m, 15.VI.2006, pheromone trap, P. glauca forest, Dominique M. Collet (1, UAM); Kenai, Kenai Peninsula, 60.5605 –151.188, 23.VI.1951, W.J. Brown (1, CNC); Ketchikan, 55.3513 – 131.652, 18-27.VIII.1951, B. Malkin (1, FMNH); Lawing, Kenai Peninsula, 60.4023 –149.364, 11.VII.1951, W.J. Brown (1, CNC); PoW Is. Staney Ck., 55.799 –133.118, 13.VI.2011, J. Stockbridge, B. Wong (1, UAM); Prince of Wales Island, Hatchery Ck.4, 55.886 –132.861, 78 m, 14- 30.V.2010, Lindgren 1, old growth, J. Stockbridge and C. Bickford (1, UAM); same except Lindgren 2 (1, UAM); Prince of Wales Island, Luck Lk. 1 Rd., 55.9781 –132.755, 101 m, 30.VII.-11.VIII.2010, Lindgren 2, old growth, J. Stockbridge and C. Bickford (1, UAM); Prince of Wales Island, Luck Lk. 3 Rd., 55.9535 –132.771, 117 m, 18.V.- 4.VI.2010, Lindgren 2, old growth, J. Stockbridge and C. Bickford (1, UAM); Prince of Wales Island, Staney Ck, 55.7972 –133.135, 63 m, 14-30.V.2010, Lindgren 1, unthinned 2nd growth, J. Stockbridge and C. Bickford (1, UAM); same except 31.V.-13.VI.2011, J. Stockbridge, B. Wong (1, UAM); Prince of Wales Island, Staney Ck., 55.7973 –133.136, 50 m, 14-30.V.2010, Lindgren 2, old growth, J. Stockbridge and C. Bickford (1, UAM); Prince of Wales Island, Staney Ck., 55.799 –133.118, 45 m, 14- 30.V.2010, Lindgren 2, old growth, J. Stockbridge and C. Bickford (1, UAM); same except 13-27.VI.2011, Lindgren 2, old growth, J. Stockbridge and B. Wong, (1, UAM); same except 24.VII.-11.VIII.2010, Lindgren 2, thinned 2nd growth, J. Stockbridge and C. Bickford (1, UAM); same except 27-14.VII.2010, Lindgren 1, old growth, J. Stockbridge and C. Bickford (1, UAM); same except 11-25.VI.2012, Lindgren 1, old growth, J. Stockbridge et al. (2, UAM); same except Lindgren 2, old growth (4, UAM); Prince of Wales Island, Staney Ck. 1B, 55.872 –133.065, 77 m, 14- 28.V.2012, Lindgren 1, clear cut, J. Stockbridge et al. (1, UAM); same except 12-26.V.2013, Lindgren 1, clear cut, J. A. Slowik and A. Hutton (1, UAM); Sterling, Corey St, 60.5395 –150.832, 90 m, 16.VII.2004, pheromone trap, P. glauca forest, Dominique M. Collet (1, UAM); same except 6.VIII.2004 (1, UAM); Walker Lake, site 11-3, 67.13–154.42, 11.VIII.1979, under Picea bark, Alnus , Salix forest, A.V. Morgan (1, DEBU); Wasilla, 61.64–149.34, 1.VIII.1988, 1, J. Pilny (1, DEBU); California: 8mi N.W. of Chester, 40.3062 –121.231, 3.VII.1991, B.F. & J.L. Carr (1, CNC); Duck Lake, Lassen Co., 40.5759 –121.282, 8.V.1921, J.O. Martin (1, CNC); Colorado: 2mi SW Pingree Park, Chirque Meadow, Larimer Co., 40.562 –105.605, 30.vi.1965, J. Wagner (1, FMNH); 6mi S of Molas Pass, Lime Creek, 37.6409 –107.698, 2895 m, 29.VII.1973, J. M. Campbell (1, CNC); 6mi South of Molas Pass, Lime Creek, 37.6409 – 107.698, 2895 m, 29.VII.1973, J. M. Campbell (1, CNC); Owl Mountain, Routt National Forest, 40.4683 –106.043, 27.VIII.1959, emergence trap,Engelmann Spruce, F.B. Knight (1, CNC); Rollins Pass, 39.9342 –105.683, 3352 m, 5.VIII.1973, J.M. Campbell (1, CNC); Idaho: Big Sand Creek, Latah Co., 46.9331 –116.548, 863 m, 2.viii.1979, bracket fungus, R. Haswell (1, TAMU); same except 15.vi.1977, under rock, creek edge (1, TAMU); Bull Trout Lake, 3.2 km SW Hwy. 21, Sawtooth Rg., Boise Co, 44.2838 –115.237, 2130 m, 6.VI.1989, A. Smetana (1, CNC); Palaouse River, Latah Co., 46.9587 –116.553, 792 m, 2.viii.1979, in bracket fungi, R. Haswell, (4, TAMU); Twin Creek For., Challis National Forest, 46.5759 –114.496, 1524 m, 25.vii.1952, B. Malkin (5, FMNH); Kansas: unspecified, Douglas County [probably in error], F. Snow (1, SEMC); Montana: 6mi W. of Saltese, Mineral Co., 47.4132 – 115.641, 1219 m, 24.vii.1975, A. Newton & M. Thayer (1, FMNH); New Mexico: Tres Ritos, 3.7 km E, Carson National Forest, 36.1306 –105.515, 31.VII.1976, shelf fleshy polypore on rotting aspen stump, J.S. Ashe (2, SEMC); Oregon: 15mi S. of Paisley, 42.477 –120.546, 4.VIII.1978, B.F. & J.L. Carr (2, CNC); same except 9.VIII.1978 (1, CNC); 15mi S. of Paisley Oregon, 42.477 –120.546, 4.VIII.1970, B.F. & J.L. Carr (1, CNC); 7.5mi SW of Fort Klamath, 42.6176 – 122.098, 8.V.1968, Campbell & Smetana (3, CNC); Aneroid Lake, Wallowa Mts., 45.209 –117.204, 2316 m, 22- 23.VIII.1956, B. Malkin (1, FMNH); Antony Lake, Blue Mountains, Baker Co., 44.9596 –118.232, 2133 m, 14.viii.1980, under bark, pine stump, R. Haswell (1, TAMU); Battle Mountain State Park, 45.2629–118.98, 30.VII.1979, B.F. & J.L. Carr (1, CNC); Blue Mountains, Pine Creek, Baker Co., 44.9764–116.87, 1219 m, 1.VIII.1975, in duff, deep conifer wood, R. Haswell (2, TAMU); Cummins Creek Trail, Siuslaw National Forest, Lane Co., 44.2676 –124.102, 95 m, 17.v.2012, old growth Picea sitchen -s/s forest, under bark, conifer logs, A. Newton & M. Thayer (1, FMNH); Grant Co., Strawberry Range, Strawberry Lake, 44.3–118.68, 1920 m, 31.V.1989, A. Smetana (1, CNC); McCredie Springs, Lane Co., 43.716 –122.277, 8.IX.1954, B. Malkin (1, FMNH); Mt. Hood Government Camp, 45.3041 –121.755, 5.vii.1942, B. Malkin (1, FMNH); Phillips Creek Road km9, 9 km NW of Elgin, Blue Mountains, Union County, 45.6086 –118.016, 950 m, 27.V.1989, A. Smetana (1, CNC); Portland, 45.5236 – 122.675, 20.V.2002, Intercept Panel trap, Industrial Site, USFS Study (1, SEMC); same except 17.VI.2002, Conifer Stand (1, SEMC); Utah: Geyser Pass, Monti Lasal National Forest, Grand County, 38.4972 –109.233, 3050 m, 9.VII.1976, J.M. Campbell (7, CNC); Warner Campground, Monti Lasal National Forest, Grand County, 38.52–109.277, 2804 m, 8.VII.1976, J.M. Campbell (1, CNC); Washington: Big Springs picnic area, Mount Spokane State Park, Spokane Co., 47.5107 –117.536, 1497 m, 28.vi.2006, mixed conifer forest; in wet debris & moss along small stream, A. Newton & M. Thayer (1, FMNH); Forks, Clallam County, 47.9502 – 124.386, 1.VI.1920, Helen VanDuzee (1, CNC); Hoh Ranger Station, Olympic National Park, 47.8597 –123.935, 182 m, 13.V.1968, Campbell & Smetana (2, CNC); Larrupin Falls, Mount Rainier National Park, 46.8354 –121.915, 1097 m, 3.VIII.1979, J.M. & B.A. Campbell (1, CNC); Mount Rainier National Park, 4.4mi E. of Sunrise, Pierce Co., 46.9327 –121.863, 1706 m, 22.vii.1975, under bark, conifer, A. Newton & M. Thayer (1, FMNH); Mt. Spokane, Spokane Co., 47.9213 –117.114, 1371 m, 22.vi.1957, Bald knob, H. S. Dybas, (1, FMNH); Port of Olympia, 7.VIII.1997, Lindgren funnel trap 409, WA DNR Project (1, SEMC); Spirit Lake, 46.2743 –122.133, 9.vii.1956, J. Baker (1, TAMU); Wyoming: Encampment, 1mi E of Bottle Creek, Carbon Co., 41.1701 –106.873, 19.vii.1986, under bark, aspen log, W. R. Suter, (1, FMNH); Yellowstone National Park, 44.4199 –110.572, 23.vi.1957, under pine bark, H. Dybas (1, FMNH).

Diagnosis. Within the Glaber group, Q. plagiatus can be distinguished by the sparse microsculpture on the abdominal segments (especially VII) ( Fig. 4d ), median lobe with relatively broad and long apical portion ( Fig. 6f–g ), male sternite VII weakly emarginate at middle and male sternite VIII with at most small, weakly impressed glabrous area ( Fig. 4e ). Females can be recognized by a combination of geography ( Q. gilaensis restricted to Gila Mountains in Arizona and New Mexico) and the broad central lobe of tergite 10 ( Fig. 7d ) (narrow in Q. longipennis ).

Redescription. Measurements ♂ (n = 5): HW/HL 1.35–1.46; PW/PL 1.07–1.12; EW/EL 0.96–1.02; ESut/PL 0.76–0.81; PW/HW 1.01–1.08; forebody length 3.4–4.5 mm.

Measurements ♀ (n = 5): HW/HL 1.36–40; PW/PL 1.08– 1.12; EW/EL 0.96–1.02; ESut/PL 0.74–0.83; PW/HW 1.04– 1.10; forebody length 3.8–4.1 mm.

Similar to Q. glaber and differing only in the following: not colour polymorphic, head and abdomen dark brownish, pronotum always paler than head, reddish to dark reddish brown, some specimens with apical and basal margins of pronotum paler than disc, apices of abdominal segments markedly paler, elytra always reddish, orange or yellowish-orange with large dark brown spot covering majority of disc; pronotum nearly always with two punctures in the dorsal row but some specimens with three or one; abdominal segments with coarse, sparse microsculpture of transverse waves separated by about twice their width; male sternite VII with weak, broad emargination, with small impunctate area that is either not or very weakly impressed ( Fig. 4d ); median lobe of aedeagus in lateral view with overall stockier build, with apical area longer and broader ( Fig. 6f–g ); female tergite X with short and broad central lobe ( Fig. 7d ).

Distribution. Distributed in the west of North America from Alaska to California, along the Rocky Mountains and then with patchy records eastward to Newfoundland.Known from the following Canadian provinces and US states:

Canada: BC, YK, AB, ON, QC, NF

USA: AK, CA, CO, ID, KS [?], MT, NM, OR, UT, WA, WY

The record from Kansas is based on a single, old specimen from Douglas County (SEMC) and the presence of Q. plagiatus in this state should be treated as doubtful until further specimens are discovered.

Bionomics. Generally, Q. plagiatus prefers montane or boreal forested habitats relative to Q. longipennis . At higher latitudes, Q. plagiatus is almost exclusively known from under pine, spruce or fir bark, usually at higher elevations or on colder slopes, while Q. longipennis can be found under aspen bark along floodplains, aspen parkland or the foothills of mountains. One specimen of Q. plagiatus was collected from under aspen bark and remains the only record from a deciduous tree. Several records exist from under stones, in river debris, from fleshy polypore fungi and wet debris, though these are likely incidental. A substantial series was attracted to a pheromone trap in British Columbia.

Comments. This species is partly sympatric with Q. longipennis in the northern part of its range (records from Quebec, Ontario, Alaska, and Yukon Territory). Within most of its range in the Rocky Mountains, it is the only species of Quedionuchus . This species is relatively poorly sampled in the east of North America and is probably more widespread in boreal Ontario, Quebec, New Brunswick and Newfoundland. Quedionuchus plagiatus is most similar to the allopatric Q. gilaensis from the high elevation conifer forests of Arizona and New Mexico but is distinguished by the less strongly emarginate male sternite VII, smaller and less strongly impressed glabrous area of male sternite VIII and the broader apical part of the median lobe in lateral view.

Figures

Fig. 4 Quedionuchus armipes Sharp, expansion of hind femur (a); Q. longipennis (Mannerheim), microsculpture of pronotum (b); Q. longipennis (Mannerheim), microsculpture of tergite V (c); Q. plagiatus (Mannerheim), microsculpture of sternite V–VI (d);

Fig. 6 Quedionuchus glaber (O. Müller) (a, West Palaearctic, b, d, East Palaearctic), Q. longipennis (Mannerheim), typical shape (c), Q. plagiatus (Mannerheim) (e–g), Q. gilaensis Brunke (i–k) and Q. armipes Sharp (l–o). Aedeagus in ventral view (l), median lobe in

Fig. 7 Female tergite X of: Quedionuchus samuraicus (Bernhauer and Schubert) (a); Q. reitterianus (Bernhauer) (b); Q. longipennis (Mannerheim) (c); Q. plagiatus (Mannerheim) (d); Q. gilaensis Brunke (E); Q. armipes Sharp (F). Scale bars = 0.5 mm