Bryotropha gemella Rutten & Karsholt, 2004, sp. n.

Bryotropha gemella sp. n.

(figs. 6, 24, 25, 38, 46, 56, 76)

Type material. Holotype, 1 ɗ: Ottawa, Can. 26.vi.1905, C.H. Young, gen. slide USNM 9885 (USNM). Paratypes, 26 ɗ, 2 Ψ. — CANADA, New Brunswick: 1 ɗ: Chamcook, 15.vi.1938, T.N. Freeman, gen. slide AR 0 546 (CNC). — Nova Scotia: 1 ɗ: Baddeck, 2.vi.1936, J. McDunnough, gen. slide AR 0 528 (CNC); 1 ɗ: S. Milford, 21.VI.1934, J. McDunnough (CNC); 1 ɗ: White Pt. Bch., Queens Co., 16.vii.1934, J. McDunnough, gen. slide AR 0 723 (CNC). — Ontario: 1 ɗ: Ottawa, 19.vii.1905, C.H. Young, gen. slide 4656 R.W. Hodges (CNC); 2 ɗ: ibid., 16.vi.1906; 1 ɗ: ibid., 21.vi.1906; 1 ɗ: Bobcaygeon, 2.vi.1932, J. McDunnough, gen. slide AR 0 649 (CNC); 2 ɗ: ibid., 8.vi.1931 [no abdomen]; 1 ɗ: Minaki, 8.vii.1928, J. McDunnough (CNC); 1 ɗ: Islington, 12.vii.1935, M.S. Parish (USNM); 1 Ψ: Ottawa, 18.vii.1905, C.H. Young, gen. slide USNM 9872 (USNM); 1 ɗ: Sparrow Lake, 9.vii.26, A.F. Braun (USNM); 1 ɗ: ibid., 5.vii.1926. — Québec: 1 ɗ: Bradore Bay, 19.vii.1929, W.J. Brown, gen. slide AR 0 530 [CNC]; 1 ɗ: Terrebonne, lac Brûlé, near Ste­Agathe, 6.vii.1994, J.­F. Landry, at MVL in mixed forest with birch, spruce, fir, maple (CNC); 1 ɗ: ibid., 9.vii.1994, J.­F. Landry, daytime on fungus­covered logs (CNC); 1 ɗ: ibid., 4.vii.1993, day, on moss growing on a boulder in mixed forest, genitalia slide m MIC 2644; 1 ɗ: Masham, Lake Duncan, ad luc, 15.vi.1985, K. Mikkola leg. (ZMUH). — USA, Michigan: 1 ɗ: Huron MTs, 26.vii.1943, A.F. Braun (USNM); 1 ɗ: ibid., gen. slide USNM 9893 (USNM); 1 Ψ: ibid., 24.vii.1943, gen. slide AR 0 668 (USNM). — New Hampshire: 1 ɗ: Bretton Woods White Mts. 1600 ft., 8.vii.1915, gen. slide USNM 13,527 (USNM); 1 ɗ: ibid., 16.vii.1923, gen. slide USNM 13,528 (USNM); 1 ɗ: 24.vii.1931, Mt. Washington 4000 ft. N.H., gen. slide USNM 13,526 (USNM). — Virginia: 1 ɗ: Mountain Lake, 14–21.vi.1907, A. Braun (USNM).

Diagnosis. Large brownish species with distinct stigmata.

Description. Adult (fig. 6). Wingspan 15–16 mm (male), 13–14 mm (female). Labial palpus without a brush underneath segment 2 and with segment 3 shorter than segment 2; ochreous to pale ochreous on the inner side, slightly darker on the outer side. Antenna dark brown very indistinctly ringed with ochreous. Head with frons pale ochreous to dark ochreous brown; vertex, thorax and tegula concolorous with forewing. Forewing dark ochreous brown, suffused with pale ochre; all stigmata very distinct, first plical obsolete; first discal beyond second plical; costal and tornal patches pale ochreous, fused to form a rather indistinct, angulated fascia; termen lined with distinct patches of blackish scales; cilia ochreous­brown with one or more ciliary lines and pale ochreous tips. Hindwing fuscous gray to fuscous brown all over; cilia concolorous, with one to several ciliary lines.

Variation. The material examined shows little variation. Individual specimens may be slightly darker or paler due to varying amounts of ochreous scales on the forewing.

Similar species. Very similar to B. galbanella q.v. The label data indicates that B. galbanella has an arctic range whereas B. gemella is found in more temperate regions, suggesting that these species are allopatric.

Male genitalia (figs. 24, 25, 38, 56). Uncus broad, subrectangular. Socius usually with 4 or 5 setae. Gnathos slender, clearly thickened at bend, base with microtrichia. Thornshield triangular, without spikes. Vinculum often covered with microtrichia but occasionally without. Apex of aedeagus with long (>200 µm) whip. Resembling B. galbanella q.v.

Female genitalia (fig. 46) Segment VIII with many microtrichia. Lamella postvaginalis small, with a narrow median extension reaching to the middle of segment VIII. The bulbous structure marking the distal end of the ventral groove not extending beyond the distal rim of segment VIII. Ventral groove very distinct, with curved margins. Dorsal side of segment VIII weakly concave. Signum large and clearly elongate, with two transverse folds; distal and proximal ends densely covered with small spikes, middle part with only few spikes. Separated from B. galbanella by the shape of the lamella postvaginalis.

Biology. Immature stages are unknown. Adults were collected from early June to late August, probably in one generation, at altitudes of up to 500 m. Several specimens were recorded during the day in forested areas, suggesting that the biology of this species may be similar to that of B. galbanella. Like B. galbanella, females of B. gemella are rarely collected: only two were present among the 29 specimens examined.

Distribution (fig. 76). Recorded from the northeast part of the USA and the adjoining southeast part of Canada.

Etymology. An adjective: gemellus: twin, referring to the similarity to B. galbanella; here in feminine in concordance with the female gender of Bryotropha.