Ablabesmyia (Karelia) pulchripennis Lundbeck

Ablabesmyia (Karelia) pulchripennis (Lundbeck)

(Figs 2 C; 3 C; 4 C, J; 5 E; 7 A–C)

Material examined. CANADA: Saskatchewan, Tobin Lake, on aquatic plants, depth 0.1 m, male reared from larva, 10.viii. 1966, A. L. Hamilton; Manitoba, gravel pit north of Seddon's Corner, male reared from larva, 27.vii. 1968, J. F. Flannagan and G. P. McRae; Alberta, shallow pond near Edmonton, male, date unknown, G. R. Daborn. Lake Winnipeg records: Gull Harbour, 1 male, 16.vii. 1969; Hecla Island, 1 male, 27.vii. 1971; Beaver Creek, emergence traps, 2 males, 22.vii. & 26.viii. 1971.

Pupa (n = 2). Total length 7.15–8.34 mm. Exuviae pale, yellowish brown.

Cephalothorax. Thoracic horn (Fig. 2 C) 761–834 µm long, 337–368 µm wide, 2.26–2.27 times as long as wide; respiratory duct (Fig. 2 C) forms a rounded "T" at apex. Thoracic comb (Fig. 2 C) consisting of 12–15 long and apically rounded spines and a few smaller ones, longest spine 72–115µm long.

Abdomen. Anal lobe (Fig. 3 C) 1.08–1.11 times as long as wide; outer margin distad of distal seta with 10–13 spinules, basad of basal seta with 0–5 weak and decumbent spinules.

Fourth instar larva (n = 1–2). Head capsule length 1.25–1.40 mm.

Head. Antenna as in Fig. 4 C. Lengths of antennal segments (in µm): 668–711, 94, 8, 4. AR 6.71. Basal antennal segment 34–40 µm wide, ring organ 0.49–0.51 from base. Mandible 230–244 µm long. Maxillary palp (Fig. 5 E) 2-segmented, basal segment 61–62 µm long, 20 µm wide; apical segment 70 µm long, 12–13 µm wide. Ligula (Fig. 4 J) 152–170 µm long. Paraglossa 60–65 µm long. Hypopharyngeal pecten with 18–20 teeth.

Abdomen. Procercus 200 µm high, 70 µm wide, 2.86 times as high as wide. Anal setae 1349 µm long, supraanal seta 638 µm long, supraanal seta/anal setae 0.47. Posterior parapods about 1100 µm long, with 2–3 darker claws. Anal tubules 343 µm long.

Remarks. The reared male from Seddon's Corner, Man., is lighter than the normal males with coloration similar to that of A. (K.) illinoensis with weak anteromesal infuscation on tergite I gradually larger infuscations on II– IV, tergites VI–VII dark, and tergite VIII dark in anterior half. The tarsal beard and the immatures, however, clearly show that it belongs to A. (K.) pulchripennis.

Distribution and ecology. This species is a northern species known from Greenland, Northwest Territories, northern Québec, the Canadian prairie provinces, Wyoming, South Dakota, Colorado, Kansas and Washington (Roback 1971: 364, 1985: 177; Oliver et al. 1990: 10, Ashe & O’Connor 2009: 124). The few specimens from Lake Winnipeg were all caught in the Narrows.