Anthomyza gibbiger, Roháćek & Barber, 2016

Roháćek, Jindřich & Barber, Kevin N., 2016, Nearctic Anthomyzidae: a monograph of Anthomyza and allied genera (Diptera), Acta Entomologica Musei Nationalis Pragae (suppl.) 56, pp. 1-412 : 255-267

Anthomyza gibbiger sp. nov.

( Figs 383 , 419, 420 , 422–436 , 439 )

Type material. HOLOTYPE: ♂, “ONT: SSMarie, S.of Algoma U.College, 12.vii.2002, KNBarber, sweeps, Carex aquatilis 46°29.9'N 84°17.2'W ” and “ HOLOTYPUS ♂ Anthomyza gibbiger sp. n., J. Roháček & K. N. Barber det. 2013” (red). The specimen is in perfect condition, with well visible, partly exposed genitalia (see Fig. 383 ) ( CNCI, intact). PARATYPES: CANADA: ALBERTA: w. border Elk Island N. P., Range Rd. 210, 0.5 km N Hwy#16, 53°34.52'N 112°57.09'W, sweeps, mixed sedges, 21.vii.2008, 2 ♂♂, K. N. Barber leg. ( CNCI). BRITISH COLUMBIA: Vancouver, Point Grey, on tidal nat, 12.vii.1973, 2 ♂♂, J. R. Vockeroth leg. ( CNCI). MANITOBA: 13 mi N Glenboro, Bald Head Hills, 21.vi.1958, 1 ♀ (genit. prep.), ex. Betula occidentalis , sand dunes, 1 ♀, J. F. McAlpine leg.; Ninette, Betula glandulosa – Populus balsamifera associes, 15.vii.1958, 1 ♂, J. G. Chillcott leg. (all CNCI); Winnipeg, St. Charles Rine Range, Arrowhead block, 49°54.6'N 97°20.5'W, sweep in tallgrass prairie, 21.vi.1999, 1 ♀, S. Boucher leg. ( LEMQ 0040119); same locality but 49°54.2'N 97°20.3'W, sweep in tallgrass prairie, 10.vi.1998, 1 ♂, P. Bouchard leg. ( LEMQ 0040124). NEW BRUNSWICK: St.Andrews, 24.vii.1978, 1 ♂, S. A. Marshall leg. ( DEBU). NOVA SCOTIA: [mistakenly labeled NB] CBHNP [Cape Breton Highlands N. P.], La Prairie, 24–29.vi.1984, 1 ♂, H. J. Teskey leg.; CBHNP, Pleasant Bay, 17.viii.1984, ex. damp meadow, 1 ♂ 1 ♀, R. Martin leg.; same locality but PG684871, 10.vii.1984, wet hardwood forest, 1 ♂, H. J. Teskey leg.; Kingsport Marsh, [-]. viii.1980, 1 ♀, C. D. Dondale leg.; Halifax Co., Lawrencetown, 19–20.vii.1967, 1 ♀ (genit. prep.), D. M. Wood leg.(all CNCI); Lockeport, 18.vii.1958, 1 ♂ 5 ♀♀ (1 ♀ genit. prep.), 20.vii.1958, 1 ♂, 21.vii.1958, 1 ♂, 22.vii.1958, 1 ♂, 27.vii.1958, 1 ♀, 1.viii.1958, 1 ♀, 11.viii.1958, 1 ♀; Lockeport, Cranberry I., 20.vii.1958, 2 ♀♀, all J. R. Vockeroth leg.; Sable Is., west end, 5. vii.1967, 1 ♀ (genit. prep.), 13.vii.1967, 4 ♂♂ 4 ♀♀ [1 ♂ with penciled label “ Poa nat”], D. M. Wood leg. (all CNCI); S[outh] Harbour, PG929935, marshy lake shore, brackish water, Carex , Iris , Juncus , 19.vi.1983, 1 ♂, 27.vi.1983, 2 ♂♂; S[outh] Harbour Bch., PG949958, 3.vii.1983, wet bare sand shore, nearly fresh water, 1 ♂, damp ground with Carex & Iris , 1 ♀, all J. R. Vockeroth leg. (all CNCI). ONTARIO: ~ 1 km NW Bewdley, Jct. Hwy 28 & Rice Lake Rd., 44°05.92'N 78°20.18'W, sweeps, mostly creekside Carex , 7.vii.2005, 5 ♂♂ 2 ♀♀, K. N. Barber leg. ( CNCI); Bruce Co., Crane River, 21.vii.1996, 1 ♀, S.A.Marshall leg. ( DEBU); Bruce Penin[sula], 1 km NNW Ague Lake, spring creek, 45°03'48"N 81°24'34"W, sweeping Calamagrostis canadensis in a fen, 1.vii.2010, 3 ♂♂ 8 ♀♀, J. Roháček leg. ( SMOC, 3 ♀♀ genit. prep.); Bruce Peninsula N. P., Crane River below Lake Scugog, 45°07.0'N 81°32.1'W, sweeps, riverside vegetation, 3.vii.1999, 1 ♂ 3 ♀♀; Bruce Peninsula N. P., Dorcas Bay Rd. at Willow Creek, 45°09.4'N 81°34.4'W, sweeps, mostly creekside graminoids, 3.vii.1999, 1 ♂; same locality but 45°09.39'N 81°34.43'W, sweeps, Carex aquatilis , 22.vi.2008, 1 ♀; Bruce Peninsula N. P., Singing Sands, 45°11.6'N 81°34.7'W, sweeps, Agropyron / Calamagrostis , 5.vii.1998, 3 ♀♀, all K. N. Barber leg. (all DEBU); Burlington, edge Tuck Ck, 43°21.2'N 79°46.6'W, sweeps/pooter, Bromus inermis , 15.vii.1997, 1 ♀, 16.vii.1997, 1 ♀, 20.vii.1997, 2 ♂♂ 3 ♀♀ (1 ♀ genit. prep.), pooter, Phleum pratense , 18.vii.1997, 1 ♀, 20.vii.1997, 1 ♀; ~ 40 km NE Chapleau, 47°59.76'N 82°55.04'W, wet roadside sweeps, mostly Carex utriculata , 23.vi.2013, 1 ♂ 1 ♀ (1 ♀ genit. prep.), 13.vii.2013, 1 ♂, sweeps, mostly Carex utriculata , grasses, 13.vii.2013, 1 ♀; ~ 2.5 km W Coboconk, Hwy 48, at Hannivan’s Ck., 44°39.29'N 78°50.20'W, sweeps, mostly waterside Carex , 7.vii.2005, 3 ♀♀, all K. N. Barber leg. (all CNCI); ~ 5 km SE Cochrane, 49°01.16'N 80°57.93'W, sweeps, railside Equisetum spp., graminoids, herbs, 18.vii.2009, 1 ♀; ~13.5 km S Cochrane, 48°56.65'N 81°00.18'W, hydro right-of-way, sweeps, mostly Carex utriculata , 22.vi.2013, 4 ♂♂ 5 ♀♀ (2 ♀♀ genit. prep.), 12.vii.2013, 31 ♂♂ 6 ♀♀ (1 ♀ genit. prep.), 13.vii.2013, 1 ♂, 18.viii.2013, 3 ♂♂ 1 ♀, 7.vii.2014, 10 ♂♂ 3 ♀♀; Dryden, 49°47.27'N 92°48.62'W, sweeps, mixed graminoids/herbs, 17.vii.2008, 1 ♀; ~ 35 km WSW Dubreuilville, 2 km SE jct. Hwys.#17 & #519, 48°17.16'N 84°53.34'W, sweeps, roadside vegetation incl. wet ditch, 31.vii.2008, 1 ♂, all K. N. Barber leg. (all CNCI); Dubreuilville, along Magpie River, 48°21.12'N 84°34.04'W, sweeping Equisetum ssuviatile , Carex spp. on muddy river bank, 10.vii.2010, 1 ♂, J. Roháček leg. ( SMOC, genit. prep.); ~ 3.8 km ENE Dugwal, 48°35.33'N 80°57.90'W, sweeps, wet ditch, Carex utriculata , Equisetum ssuviatile , Scirpus , 23.vi.2013, 1 ♀, 13.vii.2013, 4 ♂♂; Echo Bay, Echo Bay Marsh, near lookout, 46°29.66'N 84°04.12'W, sweeps, mostly Carex utriculata , 15.vi.2013, 1 ♂ (genit.prep.); same locality but 46°29.71'N 84°04.04'W, sweeps, mostly Carex incl. Carex utriculata , 24.vi.2012, 1 ♂ 1 ♀ (pair in copula); Elliot Lake, 46°22.23'N 82°36.49'W, sweeps, mixed graminoids incl. Carex utriculata , 29.vi.2013, 1 ♂; ~ 14.5 km SSE Elliot Lake, ~ 3.7 km NNE jct Hwys 17&108, 46°14.71'N 82°33.53'W, sweeps, mostly Carex utriculata , 29.vi.2013, 1 ♀ (genit. prep.), all K. N. Barber leg. (all CNCI); ~ 59 km NNW Elliot Lake, S of Rocky Island Lake, 46°50.16'N 83°03.05'W, 455 m, sweeping, mostly Carex rostrata ? [more likely C. utriculata ], in fen, 3.vii.2010, 1 ♂ 3 ♀♀ (all genit. prep.); ~ 66 km NNW Elliot Lake, Rocky Island Lake, 46°50.82'N 83°08.76'W, 405 m, sweeping Scirpus sp. [ S. microcarpus ] on dried shoreline, 4.vii.2010, 1 ♀ (genit. prep.), all J. Roháček leg. (all SMOC); Erin, 25.vi.1979, 1 ♂, Jessica Ernst leg. ( DEBU); Fergus nr. Guelph, Grand River, riverside vegetation, 30.vii.1994, 1 ♀, J. Roháček leg. ( SMOC, genit. prep.); ~7.0 km E Foleyet, 48°14.34'N 82°20.75'W, hydro right-of-way, sweeps, mostly Carex utriculata , 13.vii.2013, 5 ♂♂ 1 ♀, K. N. Barber leg. ( CNCI); Finland, S of Caliper Lake, sweep sedge at beaver dam, 10.vii.1992, 1 ♀, T. A. Wheeler leg. ( LEMQ 0040127); Goulais River, Sand Bay, 46°44.81'N 84°32.68'W, sweeping Juncus and Carex at margins of fen pools, 10.vii.2010, 1 ♂ 1 ♀, J. Roháček leg. ( SMOC, 1 ♀ genit. prep.); Greenwater P. Pk., Sandbar Lk. Trail, 49°13.10'N 81°17.35'W, sweeps, lakeshore Equisetum spp., graminoids, Caltha , 21.vii.2009, 2 ♂♂ ( DEBU 01502087, -88); Greenwater P. Pk., 49°10.91'N 81°16.28'W, sweeps, Carex , Calamagrostis , Phalaris in creek noodplain, 21.vii.2009, 1 ♂ ( DEBU 01502176), all K. N. Barber leg.; Guelph, 23.vi.1976, 1 ♀, J. M. Cumming leg., 2.viii.1980, 2 ♀♀, 3.viii.1980, 2 ♂♂ 1 ♀, 22.viii.1980, 1 ♀, pan traps, 24.vi.–14.vii.1981, 1 ♂ 1 ♀, Malaise trap, 5–30.vi.1982, 1 ♂, 1–20.vii.1982, 1 ♀, 23–30.vi.1985, 1 ♀, 1–7.vii.1985, 1 ♂, 8–14.vii.1985, 2 ♂♂, 29.vii.–3.viii.1985, 1 ♂, K. N. Barber leg. ( DEBU); ~2.0 km W Hallebourg, 49°40.36'N 83°32.11'W, sweeps, wet ditch, mostly Carex utriculata , 22.vi.2013, 1 ♂; Hurkett, dock area, 48°50.42'N 88°29.38'W, sweeps, emergent Equisetum ssuviatile , 31.vii.2008, 4 ♂♂; ~ 25 km WNW Ignace, 49°29.52'N 92°00.83'W, sweeps, fen, mostly Carex utriculata with grasses, 4.vii.2012, 1 ♀, 6.vii.2012, 2 ♂♂ 2 ♀♀, all K.N. Barber leg. (all CNCI); Innisnl, 44°19.346'N 79°35.009'W, sweep around pond embankment, 28.vii.2011, 1 ♀; Innisnl, 44°19.396'N 79°35.048'W, Malaise in fence row, 28.vii.–2.viii.2011, 1 ♀, both J. E. Swann & D. R. Edwards leg. (both BDUC); Lake Superior P. Pk., Hwy 17 near jct. Agawa Rock, 47°22.31'N 84°41.23'W, sweeps, mostly Carex utriculata , 12.vii.2014, 2 ♀♀, K. N. Barber leg. ( DEBU 01503959, -60, 1 ♀ genit. prep.); ~ 6.3 km E Macleod, 49°41.37'N 86°51.41'W, sweeps, graminoids incl. Carex utriculata & C. aquatilis substricta , 6.vii.2012, 4 ♂♂ 4 ♀♀; Manitoulin Is., 0.7 km N Michael’s Bay Pk., 45°36.5'N 82°06.2'W, sweeps/pooter, graminoids in fen nat, 28.vii.1997, 1 ♂; Manitoulin Is., ~2.2 km N Cold Springs, Perch Ck @ Hwy 540, 45°53.2'N 82°06.3'W, sweeps, various grasses / sedges in noodplain, 5.vii.1998, 1 ♂ 2 ♀♀, sweeps/pooter, Calamagrostis canadensis , 1.viii.1997, 2 ♀♀; same locality but 45°53.1'N 82°06.2'W, sweeps/pooter, Calamagrostis canadensis , 4.vii.1999, 6 ♂♂ 1 ♀ (1 ♂ genit. prep.), sweeps, various grasses / sedges in noodplain, 4.vii.1999, 1 ♂ 1 ♀, all K. N. Barber leg. (all CNCI); Manitoulin Is., Poplar, 45°46'N 82°28'W, sweep along grassy trail, 27.vi.1992, 1 ♀, T.A. Wheeler leg. ( LEMQ 0040128); Manitoulin Is., 3.3 km E Spring Bay, Hwy 542 @ Tracy Rd., 45°43.90'N 82°16.48'W, pooter, roadside/fenceline grasses, 30.viii.2004, 1 ♀; Hwy#17, ~ 8.5 km NW Marathon, 48°47.69'N 86°26.11'W, 28.iv.2012, ex. Equisetum ssuviatile , dry stalks on surface, bulk pails, [reared] misted daily, 22°C, 16L:8D, 60–70% RH, emerged: 23.v.2012, 1 ♂; Moosonee, 51°16.68'N 80°38.65'W, sweeps, mostly C [arex] utriculata , C. aquatilis , wet sedge meadow, 10.vii.2014, 7 ♂♂ 6 ♀♀ (1 ♀ genit. prep.); Moosonee, 51°16.36'N 80°39.11'W, sweeps, railside ditch, mostly Equisetum ssuviatile , Carex spp., 10.vii.2014, 1 ♂; Moosonee, 51°16.17'N 80°39.10'W, sweeps, mostly Carex utriculata , Scirpus , in wet hydro cut, 10.vii.2014, 1 ♂ 3 ♀♀; Moosonee, 51°16.55'N 80°39.01'W, sweeps, mostly Carex spp., wet forest trail, 11.vii.2014, 2 ♂♂ 1 ♀; ~ 8 km SSW Nipigon, Hwy #628, 48°57.09'N 88°19.71'W, sweeps, damp roadside, mixed graminoids, 16.vii.2008, 1 ♂, all K. N. Barber leg. (all CNCI); Ottawa, 4.vii.1956, 1 ♂, 12.vii.1956, 1 ♂ 4 ♀♀, 13.vii.1963, 1 ♀ (genit. prep.), J. R. Vockeroth leg. ( CNCI); Pancake Bay P. Pk., 46°57.74'N 84°42.63'W, sweeps, beach grasses [ Ammophila breviligulata ], 7.viii.2004, 1 ♀, K. N. Barber leg. ( DEBU 01501214); same locality but sweeping Ammophila breviligulata on beach sand, 9.vii.2010, 1 ♀, J. Roháček leg. ( SMOC, genit. prep.); Pancake Bay P. Pk., 46°58.10'N 84°42.71'W, sweeps, mostly Carex nr. wetland boardwalk, 24.vii.2004, 3 ♂♂ 1 ♀ ( DEBU 01500722–25), sweeps, mostly Carex utriculata in fen near boardwalk, 19.vii.2014, 1 ♂ ( DEBU 01503988); Pancake Bay P.Pk., 46°58.11'N 84°42.72'W, sweeps from boardwalk, mostly emergent sedges / Equisetum , 24.vii.2004, 1 ♀ ( DEBU 01500575), 2.viii.2004, 1 ♂ ( DEBU 01500872), 7.viii.2004, 3 ♂♂ 1 ♀ ( DEBU 01501088–91), 27.vi.2005, 3 ♂♂ 1 ♀ ( DEBU 01501610–13, 1 ♀ genit. prep.), 7.vii.2007, 1 ♂ ( DEBU 01501895), all K. N. Barber leg.; 10 km NW Penetanguishene, Awenda P. Pk., Second Lake, sweep sedge at shoreline, 13.vii.1992, 3 ♂♂ 1 ♀, T.A. Wheeler leg. ( LEMQ 0040120–22, -18); ~ 1 km NW Ponsonby, 43°38.2'N 80°22.9'W, sweeps/pooter, roadside, mostly Poa pratensis & Poa compressa , 17.vii.1997, 2 ♂♂ 1 ♀; Hwy 101 at Prairie Bee River (west side bridge), 47°51.81'N 83°54.33'W, sweeps, mostly Carex utriculata , 14.vii.2013, 2 ♂♂ 1 ♀, all K. N. Barber leg. (all CNCI); Kent Co., Rondeau P. Pk., South Point Trail East, 42°15'35"N 81°50'53"W, oak savanna, sweep, 9.viii.2003, 1 ♂, M. Buck leg. ( DEBU 01139614); S[ault] S[te.] Marie, Algoma U[niversity] College, sweeps, 20.vii.1987, 1 ♀ ( CNCI); same locality but 46°29.9'N 84°17.2'W, sweeps, mixed graminoids, 18.vi.1998, 2 ♂♂ 3 ♀♀, sweeps, graminoids mostly Carex aquatilis , 11.vi.1997, 3 ♂♂ 1 ♀, sweeps/pooter, Calamagrostis canadensis , 12.vii.1997, 2 ♂♂ 2 ♀♀ (1 ♀ genit. prep.), 3.viii.1997, 1 ♀, 26.viii.1997, 3 ♂♂ 4 ♀♀, sweeps, Calamagrostis canadensis & Carex aquatilis , 23.vii.1997, 1 ♂ 3 ♀♀ (1 ♀ genit. prep.), sweeps, Calamagrostis canadensis , 28.viii.1997, 1 ♂ 1 ♀, 29.viii.1997, 3 ♂♂ 4 ♀♀ (incl. pair in copula) ( CNCI), 26.vi.1998, 2 ♂♂ 2 ♀♀ ( LACM), sweeps, mostly Calamagrostis canadensis , 28.vii.2001, 2 ♂♂ ( CNCI), 29.vii.2001, 2 ♂♂ 2 ♀♀ ( LACM), 6.viii.2001, 3 ♂♂ 3 ♀♀ (1 ♀ genit. prep.), sweeps, mostly Calamagrostis canadensis & Carex aquatilis , 28.viii.1997, 2 ♀♀, sweeps, Carex / Calamagrostis , 3.viii.2002, 3 ♂♂ 4 ♀♀, sweeps, Carex / Calamagrostis , 6.viii.2002, 2 ♂♂, sweeps, Carex aquatilis , 12.vii.1997, 2 ♂♂ 1 ♀ (1 ♂ genit. prep.) ( CNCI), 22.vi.1998, 2 ♂♂ 1 ♀ ( AMNH), 26.vi.1998, 2 ♂♂, 28.vi.2002, 1 ♂ 3 ♀♀ ( CASC), 29.vi.2002, 1 ♂ 2 ♀♀ ( AMNH), 1.vii.2002, 3 ♂♂ 3 ♀♀ (2 ♀♀ genit. prep.), 5.vii.2002, 1 ♀, 9.vii.2002, 1 ♂ 4 ♀♀, 12.vii.2002, 6 ♂♂ 4 ♀♀, 31.vii.2002, 5 ♀♀, sweeps, mostly Carex aquatilis , 12.vi.2001, 1 ♂, 14.vi.2001, 1 ♀, 14–17.vi.2001, 2 ♀♀ ( CNCI), 21.vi.2001, 1 ♂, 21–22.vi.2001, 2 ♂♂ 3 ♀♀ ( INHS), 25.vi.2001, 5 ♂♂ 7 ♀♀ ( USNM), 28–30.vi.2001, 4 ♂♂ 5 ♀♀ (1 ♀ genit. prep.), 29.vi.2001, 1 ♂ 1 ♀ ( CNCI), 11.vii.2001, 3 ♂♂ 1 ♀, 15.vii.2001, 2 ♂♂ 3 ♀♀ ( SMOC), 17.vii.2001, 12 ♂♂ 11 ♀♀, 18.vii.2001, 6 ♂♂ 12 ♀♀ ( CNCI), 21.vii.2001, 1 ♂ 3 ♀♀ ( USNM), 28.vii.2001, 4 ♂♂ 1 ♀, 29.vii.2001, 1 ♀, 2.viii.2002, 1 ♂, 4.viii.2002, 1 ♂ 1 ♀ ( CNCI),all K.N.Barber leg.; same locality but 46°29.88'N 84°17.19'W, sweeps, Phalaris arundinacea , 18.vi.2005, 2 ♂♂, sweeps, mostly Calamagrostis canadensis , 18.vii.2004, 1 ♂, sweeps, Calamagrostis , 26.viii.2003, 1 ♂, sweeps, Carex aquatilis , 1.vii.2003, 1 ♂ 7 ♀♀, 26.viii.2003, 1 ♂, 21.vii.2005, 3 ♂♂ 4 ♀♀ (1 ♀ genit. prep.), 27.vii.2005, 8 ♂♂ 1 ♀, sweeps, mostly Carex aquatilis , 18.vii.2004, 1 ♂ 5 ♀♀ (1 ♀ genit. prep.), 2.vii.2007, 3 ♂♂, 12.viii.2007, 1 ♂, pooter, mostly Carex aquatilis , 21.viii.2004, 1 ♀ (genit. prep.), sweeps, trampled graminoids, mostly Carex aquatilis , 5.ix.2004, 1 ♂ 1 ♀, 7.ix.2004, 1 ♂ ( CNCI), 1.viii.2005, 6 ♂♂ 3 ♀♀ ( USNM), sweeps, Calamagrostis canadensis , 18.vii.2004, 1 ♀; same locality but 46°29.82'N 84°17.17'W, sweeps, mostly Carex aquatilis near river, 21.vii.2005, 1 ♀ (both CNCI), all K. N. Barber leg.; S[ault] S[te.] Marie, S. of Algoma University, 46°29.88'N 84°17.19'W, sweeps, mostly Carex aquatilis , 29.vi.2008, 1 ♀, sweeps, mostly Phalaris arundinacea , 6.viii.2008, 4 ♂♂, but sweeps, Carex aquatilis , Calamagrostis canadensis , 5.vii.2008, 1 ♂ 1 ♀, sweeps, Calamagrostis canadensis , Carex aquatilis , 31.viii.2008, 1 ♂, sweeps, Carex aquatilis , Typha latifolia , 6.viii.2008, 1 ♂ 1 ♀, sweeps, mostly Calamagrostis canadensis , 6.viii.2008, 3 ♂♂ 1 ♀; same locality but 46°29.81'N 84°17.15'W, sweeps, Carex aquatilis , Calamagrostis canadensis (by river), 5.vii.2008, 2 ♂♂ 3 ♀♀, all K. N. Barber leg. (all CNCI); S[ault] S[te.] Marie, Baseline Rd., 46°31.40'N 84°24.40'W, sweeps, Aster [ Doellingeria ], Rubus , Equisetum , Carex , ferns under aspen, 18.vii.2005, 1 ♀; same locality but 46°31.40'N 84°24.45'W, sweeps, edge of forest, Solidago , Rubus , Equisetum , grasses, 25.vi.2005, 1 ♀, 29.vii.2005, 1 ♂; same locality but w. of creek, 46°31.52'N 84°24.63'W, sweeps, Carex under ash / aspen, 22.vii.2005, 1 ♀; same locality but 46°31.61'N 84°24.68'W, sweeps, Calamagrostis canadensis , 20.viii.2008, 1 ♀, all K. N. Barber leg. (all CNCI); S[ault] S[te.] Marie, Bellevue Pk., 46°30.1'N 84°18.1'W, sweeps, mostly Calamagrostis , 7–8.vii.2000, 4 ♂♂ 4 ♀♀ (1 ♀ genit. prep.); S[ault] S[te.] Marie, Birchwood Pk., 46°30.7'N 84°15.6'W, sweeps, mostly Impatiens under Betula / Acer , 23.vi.1998, 1 ♀; S[ault] S[te.] Marie, Bristol Pl[ace] Pk., 46°30.8'N 84°16.6'W, sweeps/pooter, Phalaris arundinacea , 8.viii.1997, 1 ♂, sweeps, Phalaris arundinacea , 28.vi.1998, 1 ♀; same locality but 46°30.77'N 84°16.66'W, sweeps, Phalaris arundinacea under Populus , 7.viii.2008, 2 ♂♂ 1 ♀; S[ault] S[te.] Marie, Finn Hill, 46°31.48'N 84°17.36'W, sweeps, mostly Scirpus microcarpus , 14.viii.2005, 3 ♂♂ 2 ♀♀, 25.viii.2005, 1 ♂ 1 ♀, 12.ix.2005, 2 ♂♂ 3 ♀♀, 17.ix.2005, 1 ♀, sweeps, mostly Scirpus microcarpus , Impatiens , 27.vi.2007, 1 ♀, all K. N. Barber leg. (all CNCI); Sault Ste. Marie, Finn Hill, 46°31.48'N 84°17.36'W, sweeping graminoid vegetation, 7.vii.2010, 4 ♂♂ 2 ♀♀ (2 ♂♂ 2 ♀♀ genit. prep.), 12.vii.2010, 1 ♂ (genit. prep.), J. Roháček leg. ( SMOC); S[ault] S[te.] Marie, Finn Hill, 46°31.6'N 84°17.3'W, sweeps, graminoids/ composites, 19.vii.2005, 1 ♂ 3 ♀♀; same locality but 46°31.63'N 84°17.29'W, sweeps, Scirpus microcarpus , 19.vii.2004, 1 ♂ 1 ♀, 8.vii.2006, 1 ♀ (all CNCI); same locality but 46°31.63'N 84°17.33'W, sweeps, Calamagrostis canadensis , 26.vi.2007, 1 ♂ 1 ♀, 6.vii.2008, 1 ♀, 6.vii.2008, 2 ♂♂ 2 ♀♀, sweeps, Carex stipata stipata , 19.vii.2004, 4 ♀♀ ( CNCI), 20.vii.2004, 3 ♂♂ 3 ♀♀ ( NMPC), 6.vii.2008, 1 ♂ 1 ♀, 22.vii.2004, 1 ♂, 19.vii.2005, 1 ♀, sweeps, mostly Carex stipata stipata , 26.vi.2007, 14 ♂♂ 8 ♀♀ (1 ♀ genit. prep.), 13.vii.2007, 1 ♂, 16.vi.2013, 2 ♂♂, sweeps, graminoids, herbs, composites, edge of Populus tremuloides , 25.vi.2009, 7 ♂♂ 1 ♀ (1 ♀ genit. prep.), 4.vii.2009, 1 ♀ (genit. prep.), sweeps, mostly Carex / Calamagrostis , edge of Populus tremuloides , 25.vi.2009, 1 ♀, sweeps, mostly Calamagrostis , edge of Populus tremuloides , 4.vii.2009, 3 ♂♂ 2 ♀♀, sweeps, graminoids, herbs, composites, including Equisetum sylvaticum , 4.vii.2009, 2 ♀♀ ( CNCI), all K. N. Barber leg.; Sault Ste. Marie, Finn Hill, 46°31.63'N 84°17.33'W, sweeping boggy meadows, mostly Carex stipata stipata , 7.vii.2010, 11 ♂♂ 8 ♀♀ (3 ♂♂ 5 ♀♀ genit. prep., 2 ♂♂ photographed), 12.vii.2010, 4 ♂♂ 2 ♀♀ (1 ♂ 2 ♀♀ genit. prep.), J. Roháček leg. ( SMOC); S[ault] S[te.] Marie, Finn Hill, 46°31.66'N 84°17.34'W, sweeps, mostly Calamagrostis canadensis , 8.viii.2008, 3 ♂♂ 4 ♀♀ (1 ♀ genit. prep.); same locality but 46°31.7'N 84°17.5'W, sweeps, mostly sedges in trail, 4.vii.2002, 1 ♀, sweeps, mostly sedges in trail, 6.vii.2002, 1 ♀, sweeps, mostly sedges in trail, 11.vii.2002, 1 ♂, all K. N. Barber leg. (all CNCI); S[ault] S[te.] Marie, Hwy #17 city limits, 46°36.58'N 84°17.83'W, sweeps, Calamagrostis canadensis in wet area, 16.viii.2004, 3 ♂♂ 2 ♀♀, sweeps, mostly Carex / Calamagrostis in wet area, 16.viii.2004, 1 ♀ (genit. prep.), sweeps, Carex / Calamagrostis in wet area, 23.viii.2004, 2 ♂♂ 1 ♀; S[ault] S[te.] Marie, 1072 Old Garden R. Rd., 46°33.64'N 84°17.11'W, sweeps, Equisetum ssuviatile , graminoids, Typha in wet ditch, 30.vii.2007, 1 ♂; S[ault] S[te.] Marie, 2 nd Line E, 46°32.3'N 84°16.6'W, sweeps, graminoids in open meadow, 26.vi.1999, 3 ♂♂; S[ault] S[te.] Marie, Thayers Acres, 46°35.54'N 84°15.53'W, sweeps, emergent Carex sp., 1.vii.2007, 1 ♂; S[ault] S[te.] Marie, Whitensh Is./St. Mary’s Is., 46°30.68'N 84°21.20'W, riparian graminoids, sweeps, 8.viii.2004, 1 ♂ 3 ♀♀; ~ 10 km W S[ault] S[te.] Marie,Airport Rd., 46°29.72'N 84°28.96'W, natural gas r[igh]t-of-way, sweeps, mostly Scirpus / Calamagrostis , 4.viii.2004, 1 ♂, sweeps, graminoids, Equisetum , herbs, 5.viii.2009, 4 ♂♂, sweeps, graminoids, composites, Equisetum , Rubus , ferns, 14.vii.2010, 3 ♀♀, all K. N. Barber leg. (all CNCI); ~ 10 km W Sault Ste. Marie, Airport Rd., natural gas r[igh]t-of-way, 46°29.72'N 84°28.96'W, sweeping graminoids, composites, Equisetum , Rubus , ferns, 12.vii.2010, 1 ♀, J. Roháček leg.( SMOC, genit.prep.); Smooth Rock Falls, 49°16.04'N 81°36.08'W, hydro right-ofway, sweeps, Carex utriculata , 22.vi.2013, 2 ♂♂ 1 ♀; ~ 74 km NNE Thessalon, shore of Mississagi R., 46°53.94'N 83°16.23'W, sweeps, graminoids, herbs, Equisetum spp., 17.vii.2010, 1 ♂ 2 ♀♀; ~ 34 km N Timmins, 48°45.88'N 81°21.71'W, sweeps, Carex spp., 18.vii.2009, 1 ♀, all K. N. Barber leg. (all CNCI); Waubamick [sic Waubamik], [-]. vi.1915, 1 ♂, [-]. vii.1915, 1 ♂, H. S. Parish leg. ( USNM); Essex Co., Windsor, Ojibway Prairie, 42°15'51"N 83°04'30"W, 20.vii.2002, 1 ♀, S. A. Marshall leg. ( DEBU 00222430). PRINCE EDWARD ISLAND: Eglington Bay, sweep, vegetation, 20.vii.1996, 1 ♂, N. deVille leg. ( LEMQ 0040125); Greenwich N. Pk., 46°26.6'N 62°41.7'W, sweep, open areas on trail and parking area, 3.viii.2004, 1 ♂, S. Boucher leg. ( LEMQ 0040466); Victoria P. Pk., 46°12.6'N 63°28.9'W, sweep at picnic area, 2.viii.2004, 1 ♂, S. Boucher leg. ( LEMQ 0040477). QUEBEC: Chemin-du-Lac Bog, 47°46'11.4"N 69°30'43.9"W, Malaise trap, abandoned site, 4–6.vii.2006, 1 ♀, A. G. Taillefer leg. ( LEMQ 0040322); Gaspesie, Parc Forillon, Secteur Nord, route de banc, sweep near marsh, 18.viii.2006, 1 ♀, S. Boucher leg. ( LEMQ 0040301); Gaspé, Plage Haldimand, 48°47'N 64°22'W, sweep vegetation, 4.viii.2000, 3 ♂♂, H. Varady-Szabo leg. ( LEMQ 0040111–13), 2 ♂♂ 1 ♀, D. Raby leg. ( LEMQ 0040114–16); Gatineau Pk., Harrington L., 3.vii.1963, 1 ♀, J. R. Vockeroth leg. ( CNCI); Ile Bonaventure, 48°30'N 64°10'W, 3 km from Côte de Percé, sweep grass, 28.vii.2000, 1 ♀, H. Varady-Szabo leg. ( LEMQ 0040126); Îles de la Madeleine, Cap-auxMeules, Chemin du Rivage, 47°21.54'N 61°57.19'W, sweep grass near marsh, 6.viii.2004, 2 ♂♂, S. Boucher leg. ( LEMQ 0040311, -12); Îles de la Madeleine, Cap-auMeules, 47°21.7'N 61°55.86'W, 6.viii.2004, Chemin Chiasson, sweep alfalfa neld by road, 2 ♂♂, V. Dion leg. ( LEMQ 0040296, -298), Chemin du Chiasson, sweep neld along road, 1 ♀, S. Boucher leg.( LEMQ 0040510); Îles de la Madeleine, Île de la Grande Entrée, Chemin Pealey, 47°32.86'N 61°33.54'W, sweep grasses in parking lot at beach, 9.viii.2004, 1 ♂, V. Dion leg. ( LEMQ 0040295); La Trappe, 9.vii.1935, 1 ♀, J. Ouellet leg. ( AMNH); Old Chelsea, Summit King Mt., 1150', 14.vi.1963, 1 ♀, J. R. Vockeroth leg. ( CNCI); Percé, Pointe-St.-Pierre, 48°37'N 64°10'W, sweep vegetation, 8.viii.2000, 1 ♂, H. Varady-Szabo leg. ( LEMQ 0040110); St-Jean-Port-Joli, 31.vii.1952, 1 ♂, G. Steyskal leg. ( USNM); Ste-Anne-de-Bellevue, Stoneycroft Pond, 45°25.8'N 73°56.4'W, sweep grasses, 19.vi.2001, 1 ♂, H. Varady-Szabo leg. ( LEMQ 0040123). SASKATCHEWAN: Assiniboia, 27.vi.1955, 1 ♂, J. R. Vockeroth leg.; Christopher Lake, 11.vii.1959, 1 ♀, A. & J. Brooks leg.; ~6.5 km SE Langham, Hwy#16, 52°19.10'N 106°53.07'W, sweeps, mostly Carex sp., 21.vii.2008, 1 ♂ 2 ♀♀; same locality but 52°19.13'N 106°53.03'W, sweeps, mostly Elymus glaucus , 21.vii.2008, 7 ♂♂ 4 ♀♀ (1 ♀ genit. prep.), all K. N. Barber leg.; nr. Saskatoon, 44°19.346'N 79°35.009'W, sweep, roadside, 19.vii.2012, 1 ♀, J. E. Swann & D. R. Edwards leg. ( BDUC); Scout Lake, 49°20'N 106°0'W, 17.vi.1955, 2 ♂♂, J. R. Vockeroth leg.; Weyburn, 49°39.55'N 103°51.09'W, along fence next to railway, pooter, Triticeae , 28.vii.2008, 1 ♂; Yorkton, city park, 51°13.39'N 102°28.96'W, sweeps, lake margin, mostly Carex spp., 29.vii.2011, 1 ♂, both K. N. Barber leg. (all CNCI). UNITED STATES OF AMERICA: IOWA: Lake Amana, 23.vi.1928, 1 ♂, G. O. Hendrickson leg. ( USNM). MASSACHUSETTS: Dennisport, Cape Cod, 1.viii.1964, 2 ♀♀, 4.viii.1964, 1 ♀, 7.viii.1964, 1 ♂, J. R.Vockeroth leg.( CNCI); Sandwich, 22.vi.1924, 1 ♂, A. H. Sturtevant leg. ( USNM);Woods Hole, [-]. vii.1918, 2 ♂♂ ( USNM 1 ♂, AMNH 1 ♂, genit. prep., with Sturtevant det. label as A. variegata Loew ), 5–21.vii.1922, 1 ♂ ( USNM), A. H. Sturtevant leg.; Woods Hole, [-]. vii.1923, 1 ♂, [no collector] ( AMNH, genit. prep.). MICHIGAN: Livingston Co., E. S. George Reserve, 23.vii.1943, 1 ♂, G. Steyskal leg.; Rapid City, 10.vii.1941, 1 ♂, C. W. Sabrosky leg. (both USNM). NEW YORK: Buffalo, 25.vi.1909, 1 ♀, M. C. Van Duzee leg. ( CASC, with det. as Anthomyza variegata (Loew)) ; Roch, 22.vii.1942, 2 ♀♀, H. Stalker leg. ( AMNH, 2 ♀♀ genit. prep.). WASHINGTON: Dewatto, 7.vi.1906, 1 ♀, A. L. Melander leg. ( USNM, genit. prep.); Pearce Co., Tacoma, 22.vi.1982, 1 ♀, T. L. Whitworth leg. ( LACM). WISCONSIN: Washburn Co., T39N R13W B30, 4.vii.1953, 1 ♀, R. H. Jones leg. ( USNM, genit. prep.).

Other material examined (not included in type series). CANADA: ONTARIO: S[ault] S[te.] Marie, S. of Algoma U [niversity] College , 46°29.88'N 84°17.19'W, sweeps, trampled graminoids, mostly Carex aquatilis , 7.ix.2004, 1 ♂, K. N. Barber leg. ( CNCI, headless, wing illustration); Sault Ste. Marie, Finn Hill , 46°31.63'N 84°17.33'W, sweeping boggy meadows, mostly Carex stipata stipata , 12.vii.2010, 1 ♂; same locality but 46°31.48'N 84°17.36'W, sweeping graminoid vegetation, 7.vii.2010, 1 ♂, both J. Roháček leg. (both SMOC, both used for molecular analysis). ASKATCHEWAN: Assiniboia, 49°38.17'N 106°00.18'W, low wet area next to railway, sweeps, Triticeae , 1 ♂, 27.vii.2008, K. N. Barber leg. ( CNCI, abdomen lost). UNITED STATES OF AMERICA: MASSACHUSETTS: Woods Hole, [-]. viii.1922, 1 ♂, [-]. vii.1923, 1 ♀, A. H. Sturtevant leg. ( USNM, 1 ♀ genit.prep., both headless). WASHINGTON: Pearce Co., Tacoma, 22.vi.1982, 1 ♀, T. L. Whitworth leg. ( LACM, missing wings).

Description. Male. Total body length 2.22–2.78 mm; colour generally resembling that of A. variegata , thus largely (at least ventrally) yellow with highly variable ochreous to greyish brown darkenings on head, mesonotum and preabdominal terga (thus dichroic, with pale and dark forms), always with brownish dorsal band on pleuron ( Figs 383 , 419, 420 ). Head distinctly longer than high, hence more elongate than in A. variegata and A. dichroa (most resembling that of A. orthogibbus ), and anteriorly angular in pronle because of receding face. Head markedly dichroic. Pale form has head almost completely yellow (with only ocellar triangle brownish), while dark form has face, 1st antennal nagellomere and sides of occiput brown to dark brown; also frons can be partly brownish patterned in dark form (see also below). Occiput slightly concave; yellow or with faint darker stripes laterally and above foramen (pale form), or broadly brown laterally, only medially yellow (dark form); in yellow medial area there are two elongate silvery white microtomentose spots as in A. variegata . Frons relatively narrow, entirely yellow (pale form) or medially orange ochreous with brownish markings anteromedially and along orbits (dark form); ocellar triangle always brown; frontal triangle relatively dull but slightly glittering in contrast to entirely dull adjacent areas. Orbits pale yellow in both forms; silvery whitish microtomentose, less so behind posterior ors. Frontal triangle narrow, reaching about to anterior third of frons. Frontal lunule small, pale yellow. Face narrow, medially concave or folded; dull yellow and separated from parafacialia by relatively wide golden orange marginal stripe (pale form), or brown to blackish brown with darker, dull and wide marginal stripe (dark form); parafacialia and gena whitish yellow to white, with silvery white microtomentum; ventral marginal stripe of gena narrower and yellow in pale form, wider and at least anteriorly brown in dark form. Postgena and mouthparts yellow in pale form but postgena partly brown and mouthparts more or less ochreous to brownish-darkened in dark form. Cephalic chaetotaxy not distinctly different from that of A. variegata , and palpus setose as in the latter species. Eye ovoid, more elongate than in A. variegata , with longest diameter oblique and about 1.6 times as long as shortest. Shortest genal height 0.18–0.20 times as long as shortest eye diameter. Antenna nattened, geniculate; yellow with 1st nagellomere either entirely yellow in pale form or brown (also on inner side) with only basal part yellow to a variable extent in dark form; white pilosity relatively long (longer than on arista) but distinctly shorter than in A. variegata . Arista with basal segments ochreous yellow and distal seta blackish brown, 1.9–2.0 times as long as antenna, relatively shortly pubescent, with cilia markedly shorter than in A. variegata or A. dichroa .

Thorax slightly narrower than head, largely yellow, with different brown pattern in pale and dark forms; scutum in pale form yellow with pale ochreous brown sublateral bands (sometimes almost indistinct), in dark form largely brown to brownish grey with more or less distinct longitudinal ochreous yellow stripes along dc and prs-sa lines (rarely also a faint medial one) but, in contrast to A. variegata , without yellow area in front of scutellum. Humeral and notopleural areas yellow in both forms; scutellum yellow in pale form, brown in dark form. Dorsum of thorax pale grey microtomentose and relatively dull. Pleural part of thorax more shining than scutum, yellow to pale yellow (ventrally), always with brown dorsal band (narrow in pale form, wider in dark form) extended from cervix almost to haltere. Postscutellum and postnotum darker than scutellum, ochreous in pale form, brown in dark form. Thoracic chaetotaxy as in A. variegata but prs, sa and pa subequal and about as long as hu; the smaller anterior dc about as long as anterior npl, and 5–7 dc microsetae in front of anterior dc; 4 or 5 rows of ac microsetae on suture, only 2 medial rows between dc ending usually in front of posterior dc; apical sc subequal to posterior dc (both longest thoracic setae); no additional small setulae on scutellum; 2 long stpl (anterior slightly to distinctly shorter) and 4–5 upcurved setulae in dorsal half of sternopleuron plus (sometimes) 1 additional setula in front of anterior stpl, its ventral part with a cluster of 7–8 longer setae. Scutellum narrower (more elongate) than in A. variegata . Legs coloured as those of A. variegata . f 1 with ctenidial spine longer than maximum width of t 1 but usually shorter and weaker than in A. variegata ; other pedal chaetotaxies as in the latter species. Wing ( Fig. 439 ) more elongate and narrower than that of A. variegata , thus most similar to that of A. orthogibbus , with pale yellowish ochreous veins and membrane. C with very small and sparse spinulae between apices of R 1 and R 2+3. R 2+3 long, bent parallel to C with apex very slightly upcurving; R 4+5 very slightly bent to straight and parallel with (usually) straight M. Cell dm long and narrow; r-m situated in front of the middle of cell dm. Apical portion of CuA 1 longer than dm-cu and almost reaching wing margin; A 1 short, ending far from it. Alula well developed but narrow. Wing measurements: length 2.22–2.66 mm, width 0.63–0.78 mm, Cs 3: Cs 4 = 1.12–1.52, rm\dm-cu: dm-cu = 2.50–3.43. Haltere dirty yellow, both stem and knob with distinct brownish tinge.

Abdomen dorsally dichroic, dorsally differently coloured in pale and dark form. Preabdominal terga of pale form yellow-and-brown variegated ( Fig. 383 ): T1 brown with only anterior corners yellow, T2–T5 yellow with posterior transverse brown band (covering fourth to half of tergum) not reaching posterior corners, thus with sides of terga yellow. Dark form with T2–T5 either entirely brown (T4 and T5 often lighter brown) or only narrowly anteriorly and laterally yellow (most often on T4 and T5 only). T1–T5 subshining, relatively shortly and sparsely setose as in A. variegata . T1 and T2 distinctly separate, only laterally fused. T2–T4 transverse, subequal in size, T5 somewhat longer. Preabdominal sterna pale yellow, relatively narrow and becoming markedly wider posteriorly (S5 more than twice wider than S2); S1 short and slightly transverse, S2 slightly longer than wide, S3 as long as wide or somewhat wider than long, S4 and S5 (widest sternum) trapezoidal, distinctly transverse. S2–S5 densely setose, only S1 bare and with darker posterior marginal stripe. T6 bare, strongly transverse, very short and unpigmented on left, slightly longer and somewhat pigmented on right side. S6 and S7 yellow, both with brownish anterior marginal ledge; S6 with 1–3, S7 with 1–2 setae; S8 as long as but distinctly narrower than epandrium, anteriorly yellow, posteriorly brown (more extensively in dark form) and setose in posterior two-thirds.

Genitalia. Epandrium ( Figs 422, 424 ) pale yellow (contrasting with brown posterior part of S8), longer than in A. variegata or A. dichroa and broader than S8, densely setose, dorsolaterally with several longer and thicker setae (1 usually longest); anal nssure not large, rounded subtriangular. Cercus rather small and setose as in related species. Medandrium (see Fig. 422 ) relatively high, dorsally narrowed, with dorsolateral corners simple, ventrally slightly emarginate, bare. Gonostylus ( Figs 422, 424, 429 ) shortest and widest of all Nearctic species of the group, much shorter than epandrial height, relatively convex posteroexternally, of roughly (posteriorly rounded) pentagonal outline, widest in basal two-thirds, distally tapered but its apex truncate, with 2 small blunt teeth and 1 larger, more acute, internally bent posteroventral tooth, micropubescent on outer side except for anterior and apical parts, with longer setae on concave inner side, mainly posteriorly. Hypandrium ( Fig. 425 ) as in A. variegata and other relatives. Transandrium ( Figs 423, 426 ) straight and relatively robust medially (in caudal view; Fig. 426 ), with narrow nat caudal process that is medially pale and weakly sclerotized but dorsally provided with peculiar hump-shaped projection densely covered with short dark spines ( Figs 423, 425 ); a similar, but smaller version of this distinctive structure is otherwise seen only in A. orthogibbus . Distal part of caudal process is sparsely spinulose and transilient to more densely but shortly spinose basal membrane. Pregonite ( Fig. 425 ) completely fused to hypandrium as in relatives, posterior process reduced and carrying 2 longer setae, anterior section simple, relatively straight ventrally and with 3 short setae. Postgonite ( Fig. 425 ) relatively small, slender and very slightly bent, pale-pigmented and distally tapered with blunt apex; with several sensillae and 1 setula in basal two-nfths of anterior margin. Basal membrane ( Figs 425, 426 ) densely covered by small, short and nat spines (as in A. orthogibbus ). Aedeagal part of folding apparatus with small, dark grain-like tubercles ( Fig. 427 ), and with thorn-like spines (larger than in A. orthogibbus ) dorsally on hyaline striae (visible in Fig. 425 above postgonite). Connecting sclerite slender, dark, dorsally more sclerotized ( Fig. 427 ) and ventrally provided with a group of small dark blunt spines. Phallapodeme somewhat more robust than in A. variegata , basal part darker and forked, and distal part (including fulcrum) pale-pigmented and robust, with distinctly bicuspidate apex. Aedeagus ( Fig. 427 ) with small phallophore. Saccus also small compared to nlum, membranous and with short basal sclerite as in relatives, armed with some 10 robust and dark-pigmented spines as typical for the group. Filum robust, generally formed as in relatives but distally thicker, with terminal projection shortly curved and with rounded apex; tooth-like spines along dorsal surface dark but not very numerous ( Fig. 428 ). Ejacapodeme ( Fig. 427 ) very reduced, slender, pale-pigmented, with nne digitiform projection.

Female. Similar to male unless mentioned otherwise. Total body length 2.70–3.49 mm. Head not dichroic, face always and occiput usually pale (occasional darker specimens have a diffuse brown area on the postgena that can extend onto the occiput, which is never apparent in A. orthogibbus ); 1st nagellomere variably coloured, ranging from almost uniformly yellow to partly or largely ochreous to brownish-darkened on outer side. Pattern of thoracic scutum different from that of males, largely yellow to dark yellow or with very faint lateral ochreous orange darkening (the latter sometimes more strongly darkened in those females with a darkened postgena); also dorsal brownish band on pleural part of thorax usually narrower and paler than in males, usually not widened anteriorly to bottom of spiracular plate (often so in A. orthogibbus and darker A. gibbiger females). Wing measurements: length 2.58–3.31 mm, width 0.75–1.03 mm, Cs 3: Cs 4 = 1.12–1.36, rm\dm-cu: dm-cu = 2.60–3.36. Abdomen with T2–T6 entirely yellow, or with only very narrow and often faint pale brown to ochreous stripes at posterior margin (usually somewhat darker on more posterior tergites and often medially interrupted on T4–T6, but more strongly developed in females with a darkened postgena), only T1 may be largely pale brown or ochreous with anterior corner pale yellow. T2–T5 shorter and more transverse than in male, subequal in size, wider than T6. Preabdominal sterna pale yellow, slightly narrower than in male, S2 as long as wide, S3 slightly, S4 more, S5 distinctly transverse and trapezoidal. S5 largest and widest but narrower than postabdominal S6.

Postabdomen ( Figs 431, 432 ) moderately long, tapered posteriorly, telescopic, with sclerites yellow to pale yellow, T6 often and T7+S7 usually with posterior brown stripe. T6 simple, large (but narrower than T5), suboblong with rounded corners, entirely yellow or with variously developed narrow posterior stripe, with dense setae in posterior two-thirds, marginal longest. S6 transversely suboblong to slightly trapezoidal with corners rounded, broader and more transverse than S5, pale yellow and nnely densely setose. Tergosternum T7+S7 conically tapered, shorter dorsally, longer ventrally, yellow with distinct (rarely missing) brown stripe along posterior margin ( Fig. 431 ) reaching onto ventral side where faded ( Fig. 432 ); T7+S7 ventrolaterally less expanded than in A. variegata and anteriorly forming smaller and more ventrally situated lobes ( Fig. 432 , see left side; on right side the lobe is somewhat malformed and hence atypically small), largely yellow or with faint darkening at poorly denned posterior margin; medioventral raised area ( Figs 431a , see ventral arrow, 432) pronounced (bulging) in contrast to that of A. orthogibbus ; in lateral view the segment is distinctly shorter medially because its anterior lobes are situated ventrally ( Fig. 431a , see anteroventral arrow), and not anteriorly angular as in A. orthogibbus . Dorsal parts of T7+S7 ( Fig. 431 ) with characteristic short setae at posterior dark margin (shared with A. orthogibbus ), ventral part setose medially in posterior two-thirds ( Fig. 432 ). 8th segment elongate, micropubescent laterally. T8 yellow, narrow but only slightly longer than wide ( Fig. 431 ), thus shorter than in relatives, with indistinct anterior margin, posteriorly rounded, distinctly micropubescent, with nne but less exclinate setae than in A. variegata ; S8 ( Fig. 432 ) markedly wider and longer than T8, medially divided into 2 convex, nnely hirsute and micropubescent sclerites as usual. Genital chamber (uterus) posteriorly with pale-pigmented internal sclerotizations ( Figs 433, 434 ) composed of 3 pairs of nat, pale and poorly denned, partly fused sclerites (obviously longer than those of A. orthogibbus ) situated posterior to 1 suboval, strongly asymmetrically bent annular sclerite. Membranous part of genital chamber ( Fig. 436 ) long, without small grainlike sclerotizations but with pale and poorly visible ventral plate in front of insertion of ducts. Ventral receptacle ( Fig. 436 ) tube-like, hyaline, basally somewhat widened, distally tapered and terminally with strongly twisted vermicular apex. Accessory gland small, hyaline and poorly visible, with simple surface, on distally dilated and somewhat ringed duct. Spermathecae (1+1) rounded cylindrical ( Figs 430, 435 ), each with small terminal cup-shaped invagination (shallower than in A. orthogibbus ) and several minute blunt spinulae in basal quarter; duct very long and ending in short but visible hyaline cervix inserted centrally in spermathecal body. T10 very small ( Fig. 431 ), slightly longer than broad, with 1 posteromedial pair of long setae and very reduced micropubescence. S10 longer and wider than T10, subpentagonal in ventral view ( Fig. 432 ), nnely setulose and micropubescent. Cercus moderate, slender, with numerous nne setae, apical and dorsopreapical longest ( Figs 431, 432 ).

Discussion. This new species forms a sister pair with A. orthogibbus sp. nov., best characterized by a unique synapomorphy, the peculiar hump-shaped projection on the caudal process of the transandrium (cf. Figs 423, 425 ). Additional (possibly apomorphic) characters shared by Anthomyza gibbiger sp. nov. and A. orthogibbus include the thorn-like spines on the hyaline striae in the aedeagal part of the folding apparatus, a group of short dark spines on the distal end of the connecting sclerite, shortened setae at the dorsal posterior margin of the female T7+S7 and 3 pairs of (albeit weakly sclerotized) posterior sclerites in the female genital chamber. Other characters that are plesiomorphic or of uncertain polarity include shorter ciliation of the 1st nagellomere, narrower wings, a longer epandrium and a female T7+S7 that is dorsally complete and with small anterolateroventral lobes.

In the male sex, A. gibbiger is easily recognizable by its short and broad gonostylus ( Fig. 429 ), unique in the A. neglecta group. It also differs from its nearest relative, A. orthogibbus , by the presence of male dichroism (having a dark form) and by the long male ctenidial spine on f 1 (both as in A. variegata and A. dichroa ). By contrast, the female ctenidial spine of A. gibbiger is similar to that of A. orthogibbus females (not shortened in the latter as in the male) making their differentiation difncult, particularly because they often occur syntopically (see below). The female of A. gibbiger can be distinguished from that of A. orthogibbus mainly by a collection of details in the postabdomen, particularly by the less distinct transverse stripe on T1–T6 and the dorsal part of T7+S7, the shorter T8, the more transverse S6, the smaller annular sclerite and the shallower terminal invagination of the spermathecae, but all of these differences are rather subtle due to variability of these structures. The best character by which to differentiate females is the lateral view of the T7+S7, which in A. gibbiger is relatively short and without an angularly projecting anteromedial margin ( Fig. 431a ). Furthermore, the females of A. gibbiger with a diffuse darkening on the postgena, though rare and not consistently dark in all aspects of striping on the notum and abdomen, include the darkest of the A. gibbiger females and are unlike any female of A. orthogibbus and readily diagnosed by this character alone.

Etymology. The species name gibbiger is a Latin adjective (= carrying a hump) referring to the peculiar hump on the dorsal part of the caudal process of the transandrium in the male internal genitalia.

Biology. This is a species that often occurs in moist sites most often in association with sedges (often along with A. orthogibbus ) including Carex aquatilis , C. stipata var. stipata , and Scirpus microcarpus as at Ontario: Sault Ste. Marie (e.g. Fig. 421 ), and C. utriculata , as at many Ontario sites, as well as mixtures of some of these species, as at Ontario: Moosonee. Anthomyza gibbiger is usually more commonly encountered in these habitats in Ontario than is A. orthogibbus . In addition, neld collections obtained from the grass Calamagrostis canadensis on moist sites (Ontario: Sault Ste. Marie, Manitoulin Island) yielded these two species, again with A. gibbiger present in larger numbers. This all suggests a capacity in both species to use a range of plant hosts with physical factors like moisture possibly acting as more important determinants of acceptable habitat. A single male was reared from stalks of Equisetum ssuviatile (Ontario: Marathon) that were principally collected for the rearing of A. vockerothi and A. equiseti . This singular rearing however could be the result of contamination with Carex aquatilis which grew in close association with the E. ssuviatile even though similar low-frequency rearings of A. orthogibbus were made from larvae extracted directly from the nodes of E. ssuviatile (see discussion under that species). As a contrast, dry roadside habitat was also successfully sampled (Saskatchewan: Langham, Elymus glaucus Buckley ; Ontario: Ponsonby, Poa spp.) for A. gibbiger , the latter site also yielding A. dichroa . Anthomyza gibbiger nies at least from 7 June (Washington: Dewatto) to 17 September (Ontario: Sault Ste. Marie).

Distribution. With an extensive western distribution, this is the only transcontinental species of the A. neglecta group. It was also the only member of the species group encountered in Ontario: Moosonee, which is a relatively northern site. Canada: Alberta, British Columbia, Manitoba, New Brunswick, Nova Scotia, Ontario, Prince Edward Island, Quebec, Saskatchewan; United States of America: Iowa, Massachusetts, Michigan, New York, Washington, Wisconsin (see Table 2).

Figures

Figs 381–384. Primary types of the Nearctic species of the Anthomyza neglecta group. 381 – A. variegata (Loew, 1863), lectotype male, laterally and type labels, body length 2.50 mm; 382 – A. dichroa sp. nov., holotype male, laterally, body length 2.74 mm; 383 – A. gibbiger sp. nov., holotype male, laterally, body length 2.78 mm; 384 – A. orthogibbus sp. nov., holotype male, laterally, body length 2.62 mm. Photo by J. Roháček.

Figs 419–421. Living Anthomyza gibbiger sp. nov. and its habitat. 419 – A. gibbiger sp. nov., male, pale form, dorsally, body length ca. 2.6 mm; 420 – same specimen, laterally (Canada: Ontario: Sault Ste. Marie, Finn Hill); 421 – wet meadow at Sault Ste. Marie (Finn Hill), habitat of three species of the A. neglecta group, viz. A. gibbiger, A. orthogibbus and A. dichroa. Photo by J. Roháček.

Figs 422–429.Anthomyza gibbiger sp. nov., paratype male (Canada: Ontario).422 – external genitalia, caudally; 423 – transandrium, dorsally; 424 – external genitalia, laterally; 425 – hypandrial complex, laterally; 426 – transandrium, caudally; 427 – aedeagal complex, laterally; 428 – apex of nlum, subventrally; 429 – gonostylus, laterocaudally (widest extension). Scales = 0.05 mm (Fig. 428) and 0.1 mm (others).

Figs 430–436. Anthomyza gibbiger sp. nov., paratype female (Canada: Ontario). 430 – spermatheca; 431 – postabdomen, dorsally; 431a – lateral outline of T7+S7; 432 – postabdomen, ventrally; 433 – female internal sclerites, laterally; 434 – the same, ventrally; 435 – spermatheca; 436 – distal part of female genital chamber, laterally. Scales = 0.2 mm (Figs 431, 431a, 432), 0.05 mm (Figs 430, 435) and 0.1 mm (others).

Figs 437–440. Wings of the Nearctic species of the Anthomyza neglecta group. 437 – A. variegata (Loew, 1863) male, wing length 2.4 mm (USA:Tennessee); 438 – A.dichroa sp.nov., male, wing length 2.5 mm (Canada:Ontario); 439 – A. gibbiger sp. nov., male, wing length 2.3 mm (Canada: Ontario); 440 – A. orthogibbus sp. nov., male, wing length 2.5 mm (Canada: Ontario). Photo by K. N. Barber.