Culicoides regalis Majumdar & Das Gupta

(Fig 8a–i)

Culicoides regalis Majumdar & Das Gupta, in Majumdar, Das Gupta & Gangopadhyay 1997: 31; Majumdar 1972: 188–192; Nandi 2014: 102–104

Materials examined. Holotype (1 ♀), Darjeeling Govt. College, 27.v.1968, Coll. Dr. S.K. Das Gupta; Allotype (1 ♁), Darjeeling Govt. College, 21.vi.1968, Coll. Dr. S.K. Das Gupta; 13 ♀, PHE camp, Neora Valley National Park, 14.iii.2021, Coll. S.K. Sinha; 2 ♁ Bhotaykhadka, Neora Valley National Park, 19.x.2019, Coll. S.K. Sinha.

Diagnosis. Antenna with SCo on flagellomeres 1, (9,10), 11–13; mandible with basal 4 broad, outwardly directed teeth; pale spot over r-m cross vein broad, extending to cell m 2; broad dark band apical to r-m crossvein continuous to cell m; poststigmatic pale spot separated from vein M 1, distal pale spot confluent with vein M 1; anal cell with constricted distal pale spot.

Female.

Head (Figs 8a and 8b). Eyes contiguous for 3 facets. Antenna with SCo on flagellomeres 1, (9, 10), 11–13. Third palpal segment long, slender tapering beyond the mid point with numerous capitate sensilla and without sensory pit; fifth segment with 4 apical sensilla. Mandible with basal 4 broad, outwardly directed teeth.

Thorax. Scutum brownish with distinct dark brown anterior and posterior margin; 3 longitudinally dark linear streaks; postscutellum dark.

Legs (Figs. 8c and 8d). Brownish; fore and mid femora with pale basal, apical bands, hind femora with pale basal band, fore and mid tibiae with basal pale band, hind tibia with distinct basal and apical bands; hind tibial comb with 6–7 spines, second one long; spur tip frayed; claws equal.

Wing (Fig. 8e). Pale area covering wing base, base of veins and proximal half of anal cell extending to posterior wing margin; pale spot over r-m crossvein reaching vein M, continuous to cell m, above Cu fork; poststigmatic pale spot covering almost entire 2 nd radial cell and extending broadly to wing margin, sometimes reaching vein M 1 posteriorly, confluent with proximal pale spots of cells m 1 and m 2; cell r 3 distal pale spot distant from wing margin, near to vein M 1; vein M 1 bordered by pale streak; cell m 1 with a distal small oval spot not reaching wing margin; cell m 2 with two spots, one anterior to Cu fork, the distal one large meeting with wing margin; cell cua 1 with a pale spot extending to posterior wing margin, touching vein CuA 1; proximal portion of dark spot over vein CuA 2 broad, narrowing posteriorly; anal cell with broad, medially constricted distal pale spot, some with two separated spots.

Abdomen (Fig. 8g). Brownish with dark streaks; two well developed, ovoid, subequal spermatheca well sclerotized with short oblique necks; tubular rudimentary spermatheca small; small sclerotized ring present.

Male. Similar to female with usual sexual differences.

Genitalia (Figs. 8h and 8i). Sternum IX broad with depressed caudal margin. Tergum IX without apicolateral process; posterior margin of tergum IX terminating before apex of gonocoxite. Gonocoxite broad basally, narrowing apically with distinct dorsal root. Gonostylus dilated at base, curved medially, terminating with a blunt tip. Aedeagus weakly sclerotized with short, bent basal arms, stem ending with tubular round tip. Parameres broad basally with basal arms, stem dilated, gradually tapering.

Immatures. Unknown

Larval habitat. Unknown

Distribution. India (Darjeeling, Tindharia, Kurseong, Neora Valley National Park, West Bengal)

Remarks. This widespread species resembles C. isoregalis but differs in having a broad pale spot at base of wing extending to posterior wing margin in anal cell and presence of a constricted bilobed distal pale spot in anal cell. This species shows similarity with C. neoregalis but varies in antennal ratio, palpal ratio (Table 1), presence of many pale areas in wings, pale spot over cell 2 nd radial cell straddling over vein M 1, aedeagus terminating in more bulbous tip in C. neoregalis. C. regalis looks alike C. pararegalis have overlapping morphometric data but differs from this in having a larger pale spot in cell r 3 and a single, constricted distal pale spot in anal cell. These characters may be variable therefore C. pararegalis so may in fact be a single, variable species but this requires further validation to confirm. Majumdar (1972) mentioned variability of SCo on segments 5-8 in C. regalis and also absent on flagellomeres 9 and 10 in specimens collected from NVNP.