Table 1; Figs 4, 11–12, 17
Dolerus neoaprilis MacGillivray, 1908: 126. Lectotype female examined. Labelled: " INHS Insect Collection 183,581 " [printed], "F. Rauterberg Collection, NEB" [former printed, "NEB" handwritten], " Type of Dolerus neoaprilis A. D. MacGillivray, Ƥ " [printed, red], " Dolerus neoaprilis MacG." [handwritten, red frame]; Frison 1927: 242 (lectotype designation).
Dolerus subfasciatus neoaprilis: Benson 1956: 59.
Dolerus subfasciatus auct. non F. Smith, 1874
Distribution. We have examined specimens from the following states and provinces: CANADA: Alberta, Newfoundland, Northwest Territories, Nova Scotia, Ontario, Quebec. USA: Alaska, Colorado, Idaho, Maine, Massachusetts, Michigan, Nebraska, New Hampshire, New York, Virginia. Goulet (1986) recorded this species under the name D. subfasciatus from across Canada and northern United States. This species is not Holarctic as has been suggested, e.g., by Benson (1962) and Goulet (1986).
Specimens studied (USNM if not stated otherwise). CANADA: ALBERTA, 20 mi [les]. W. Legal, George Lake, 31.V- 3.VI. [19] 78, Malaise trap, D.R. Smith [leg.], 1 Ƥ; Bilby, 20.VII. 1924, O. Bryant [leg.], 1 Ƥ, same, 21.VII. 1924, 1Ƥ, same 28.VII. 1924, 2Ƥ; NEWFOUNDLAND, Cormack, 24. VI. 1966, D.R. Smith [leg.], 1 Ƥ; 28 mi. NW Deer Lake, 29.VI. [19]’ 66, D.R.Smith [leg.], 1 Ƥ; 3 mi. SE St. George’s, 27. VI. 1966, 1Ƥ 13; NORTHWEST TERRITORIES, Norman Wells, 27.V. 1953, C.D. Bird [leg.], 1 Ƥ 13, SDEI; Ft. Providence, MacKenzie R., 8.VII. 1903, Mack., 1 Ƥ; NOVA SCOTIA, 5 mi. E Antigonish, 26. VI. 1966, D.R. Smith [leg.], 5 Ƥ; ONTARIO, North Bay, 24.VI. 1967, NLHKrauss, 1 Ƥ; QUEBEC, James Bay Hwy [highway] km 68, 18.VI. [19] 85, Sweeping, H.Goulet, D.R. Smith [leg.], 1 Ƥ 13. USA: ALASKA, Anchorage, 30.V. 1948, F.S. Blanton [leg.], 1 Ƥ; Eklutha, 1.VII. 1956, R.L. Washburn, 1 Ƥ; Fairbanks, July 2, 1921, J.M. Aldrich coll. 1 Ƥ; Matanuska, VI.[19] 44, 44-27645 Trap, J. Chamberlin [leg.], 1 Ƥ 13; Matanuska, 17.V. 1945, rotary trap, J.C.Chamberlin [leg.], 1 Ƥ; same data but 5.VI. 1945, 13; Nenana, 13.VI. 1951, R.I. Sailor [leg.], 2 Ƥ; Toolik Lake, Alaska Pipeline Rd., Wash. Cr., 21.VI. 1978, on Salix, S. MacLean [leg.], 1 Ƥ; COLORADO, Garland, 18 - 6, coll. C.V. Riley, 1 Ƥ; Gothic, 9600 ft., 7-1929, M.J. Brown, 1 Ƥ; Veta Pass, 1.7, coll. C.V.Riley, 1 Ƥ; IOWA, Clermont, 28.VI. 1929, A.H. Rolfs [leg.], 1 Ƥ; MAINE, Aroostook Co, Littleton, 8.VI. 1967, D.R. Smith [leg.], 2 Ƥ; Augusta, 1.VI. 1946, A.E. Brower [leg.], 2 Ƥ 13; Kennebec Co, Litchfield, 3.VI. 1967, D.R. Smith [leg.], 1 Ƥ; Oxbow, 6.VI. 1941, A.E. Brower [leg.], 13; Penobscot Co. Enfield, 7.VI. 1967, D.R. Smith [leg.], 4 Ƥ; Piscataquis Co, Brownville Junction, 27.V. 1966, D.R. Smith [leg.], 1 f; Waldo Co, 5 mi N Belfast, 25.V. 1966, D.R. Smith [leg.], 1 Ƥ; MASSACHUSETTS, Arlington, 28.V. 1920, C.S. Sperry [leg.], 1 Ƥ; Reading, 10.VI. 1919, J.V. Schaffner [leg.], 1 Ƥ; Springfield, 4.V. 1903, F. Knab, 1 Ƥ; Stoneham, 28.V. 1932, Blackburn [leg.], 1 Ƥ; Watertown, 28.VI. 1920, C.S. Sperry [leg.], 1 Ƥ; MICHIGAN, Delta Co. 11.VI. 1960, R.&K. Dreisbach [leg.], 1 Ƥ; NEBRASKA (lectotype); NEW HAMPSHIRE, Coos Co. 10 mi. E Groveton, 18.VI. 1983, D.R.Smith [leg.], 1 Ƥ; NEW YORK, Franklin Co, 5 mi. E of Tupper Lake, 9.VI. 1983, D.R. Smith [leg.], 1 Ƥ; Hamilton Co. 5mi. SE Blue Mountain Lake, 5.VI. 1983, D.R. Smith [leg.], 1 Ƥ 13; VIRGINIA, Blackburg, 25.IV. 1960, S.L. Douthat [leg.], 13; Clarke Co, U. Va. Blandy Exp. Farm, 2 mi S. Boyce, 39 °05’N, 78 ° 10 ’W, 28.IV- 10.V. 1993, Malaise trap, D.R. Smith [leg.], 1 Ƥ; Craig Co, Cr. at Rt. 666, Huffman, 1.V. 1978, C.M. & O.S. Flint, Jr, 1 Ƥ.
Host plant. One larva reared on Equisetum arvense from Ottawa and described as that of D. (E.) subfasciatus by Leblanc & Goulet (1992) belongs to this species.
Taxonomic notes. MacGillivray (1908) did not give the number of specimens, but Frison (1927) listed only a single female as “ Type ”. We regard Frison’s action as the designation of a lectotype in accordance with Article 74.6 (ICZN 1999). Goulet (1986) found no morphological evidence to distinguish the black Japanese females of D. subfasciatus as subspecifically distinct from the Nearctic bicoloured form (D. neoaprilis) and synonymized D. neoaprilis with D. subfasciatus (he likely had no males of the latter species). The species is most similar to Dolerus pseudoanticus, and the two can be distinguished with certainty only by ovipositor structure (see Table 1 for separating it from other resembling Palaearctic species). It can be easily distinguished from D. subfasciatus by its predominately red abdominal segments 2–6 (in females and males) and tergum 1 bearing almost no punctures and setae (in females).