Figures 7, 9, 33–35
This species is closely related to and difficult to distinguish from S. vicaria. The R 2 vein in the forewing of S. nigra is forked equal to or apical of the junction of the Sc and R 1 veins. The length of this fork varied among the S. nigra specimens I examined, but it usually was about one-half the distance to the junction of Sc and R. The head, antennae, and thorax are dark brown to black in color. In lateral view, the ectoprocts of the male terminalia are twice as long as wide (Fig. 33). In dorsal view, the ectoprocts are roughly parallel-sided for the basal three-fourths, and with the apical one-fourth abruptly arching mesad and tapering to a point (Fig. 34). The parameres of the gonarcus complex are roughly L-shaped and less than one-half the length of ectoprocts. Female terminalia have tergite 9 broadly triangular in lateral view and with only a posterior articulation ridge (Fig. 35).
Sisyra nigra has a Holarctic distribution and is widely distributed in Canada, Europe and the northern United States. Most previously published North American records for this species have been reported under the name S. fuscata (Fabricius) which Leraut (1980) indicates is a junior synonym of S. nigra. New distributional records for S. nigra are reported here from Newfoundland and Nova Scotia, Canada, and Montana and Vermont in the United States. The adult flight period ranges from June to August. Adults of S. nigra and S. vicaria are occasionally collected in the same habitats (Parfin & Gurney 1956), although the former is not as common as the latter.
Published and Supplemental State and County Records. CANADA. British Columbia: (Walker 1853). Ontario: (Walker 1853). Quebec: (Walker 1853). UNITED STATES. Alaska: (Walker 1853). Indiana: county unknown (Smith 1925). Maine: county unknown (Walker 1853), [Kennebec, Hancock] (Parfin & Gurney 1956); Penobscot (BYUC), [Aroostook] (USNM). Massachusetts: county unknown (Parfin & Gurney 1956). Michigan: county unknown (Walker 1853), [Allegan], Houghton, Livingston (Parfin & Gurney 1956), [Wayne] (Parfin & Gurney 1956); Kalamazoo (AMNH), Cheboygan (SEMC). Minnesota: county unknown (Walker 1853), Cass, [Itasca] (Parfin & Gurney 1956). New York: county unknown (Walker 1853), [Hamilton] (Parfin & Gurney 1956). Wisconsin: county unknown (Walker 1853), [Jefferson, Washburn] (Parfin & Gurney 1956), Barron, Florence, Jefferson, Marquette, Oneida, Sheboygan, Walworth, Washburn, Waukesha, Waupaca, Wood (Throne 1971).
New State Records. CANADA. New Foundland: Terra Nova Natl. Park, Junction Pond, Notre Dame Cp., 12 -VII- [19] 61, 3 adults (sex not determined) (USNM). Nova Scotia: Juniper Park, W of Beechville, 7 -VIII- 1965, R. A. Evers, 2 females (INHS). UNITES STATES. Montana: Missoula Co., Salmon Lake, 7.5 mi. N of jct 200 & 83, 23 - VII- 1988, P. Skelley, UV-light, 6 males, 11 females (DEB); same, but 1 male (FSCA). Vermont: Orleans Co., 2 mi N of East Charleston on north shore of Echo lake, 18 -VIII- 1967, Sweeping, M. A. Deyrup, 1 adult (sex not determined) (AMNH).