Diamesa arctica (Boheman), 1869

Krasheninnikov, Andrey B., Makarchenko, Eugenyi A., Semenchenko, Alexander A., Gavrilo, Maria V. & Vshivkova, Kristina A., 2020, Morphological description and DNA barcoding of some Diamesinae (Diptera Chironomidae) from the Severnaya Zemlya Archipelago and the Vaigach Island (Russian Arctic), Zootaxa 4802 (3), pp. 587-600 : 590-592

Diamesa arctica (Boheman)

( Figs. 5–7 )

Chironomus arctica Boheman, 1865: 574 .

Diamesa arctica (Boheman) Holmgren 1869: 8 , 48; Edwards 1924: 173; Goetghebuer 1939: 18; Kureck 1966: 276; Serra-Tosio 1967: 205; Hansen & Cook 1976: 60; Makarchenko 1980: 89, 1985: 87, 2006: 266, 476, 614; Ashe & O’Connor 2009: 270.

Diamesa poultoni Edwards 1922: 197 , 213.

Diamesa flavipila Edwards 1922: 214 .

Material examined. 2 adult males, RUSSIA: Vaigach Island , Lyamchin Peninsula, stream in the vicinity of Bolshoy Lyamchin Nos Cape, N 69.860028 E 59.133417, 07.VIII.2015, leg. A. Krasheninnikov ; 1 adult male, same location except, N 69.857806 E 59.147222, 07.VIII.2015, leg. A. Krasheninnikov.

Adult male (n=3). Total length 5.1–5.6 mm. Wing length 3.4–3.6 mm. Total length/wing length 1.53–1.59.

Сoloration. Total color dark brown, wings greyish.

Head. Eyes pubescent. Temporal setae including 18–24 verticals and postorbitals in one group and 4–6 orbitals. Clypeus with 15–18 setae. Antenna with 13 flagellomeres and well-developed plume; terminal flagellomere with 1 subapical seta 47 μm long; AR 1.59. Palpomeres lengths (in μm): 62; 78–109; 140–172; 140–156; 203–234. Pal- pomere 3 in distal part with sensilla capitata with diameter 18–20 μm.

Thorax. Antepronotum with 7–13 ventrolateral setae. Dorsocentrals 10–20, prealars 11–14. scutellars 34–36 setae.

Wing. R with 11–15 setae, R 1 with 9–14 setae, R 2+3 with 1–2 pores, R 4+5 with 10–11 setae. Costa extension 78 μm. Anal lobe well developed. Squama with 40–49 setae. VR 0.87–0.91.

Legs. Spur of fore tibia 93 μm long; both spurs of mid tibia 62 μm long; of hind tibia 93 μm and 78 μm long. Hind tibial comb with 21setae. Lengths (in μm) and proportions of legs in Table 2.

Hypopygium ( Figs. 5–7 ). Tergite IX with 11–15 setae (from one side) and anal point 160–235 μm long. Lat- erosternite IX with 4–7 setae. Phallapodeme 156 μm long. Transverse sternapodeme 125 μm long. Basal plate fairly developed, obtuse to right-angle distomedially. Gonocoxite 310 μm long; medial field well developed, with numer- ous microtrichia and setae; distal end of medial field free. Basimedial setal cluster absent. Gonostylus 190 μm long, slender, broadest at about 0.2 its length; megaseta 12 μm long. HR 1.61–1.73.

Comments. Morphological descriptions of the D. arctica from different regions of the Arctic are similar ( Hansen & Cook 1976; Makarchenko 1985) but the data obtained after comparing the sequences of populations from Svalbard, Greenland, Northern Canada, Ellesmere and Baffin Islands are different (see below) which indicates the heterogeneity of this species. Therefore, in our opinion, an additional comprehensive revision of the populations of this species from different areas of the range is necessary.

Distribution. Holarctic Arctic species, known from Arctic regions of Eurasia and Alaska ( Ashe & O’Connor 2009).

Figures

FIGURES 1–7. Diamesa urvantsevi sp. nov. (1–4) and D. arctica (Boheman) (5–7), males. 1, 6, hypopygium in dorsal view; 2, gonostylus; 3–4, “anal point”; 5, inner structures of hypopygium; 6, distal part of gonostylus. Scale bar 20 μm.