Diamesa nivoriunda (Fitch)

Makarchenko, Eugenyi A., 2023, Correction of mistakes. I. New synonyms of two species Diamesa Meigen (Diptera: Chironomidae, Diamesinae) from the Russian Far East, with redescription of D. tsutsuii Tokunaga and D. nivoriunda (Fitch), Zootaxa 5297 (1), pp. 144-150 : 148-149

Diamesa nivoriunda (Fitch)

( Figs. 5–6 )

Chironomus nivoriundus Fitch, 1847: 282–283 .

Diamesa nivoriunda (Fitch) . Johannsen, 1903: 439–441, 1934: 348, 1937: 34–35; Roback, 1957: 51–53; [non] D. nivoriunda (Fitch) . Sublette, 1964: 130, 132 (misdetermination of a western species with hairy eyes).

Diamesa bogatovi Makarchenko, 2012: 86 . Syn. nov.

Material examined. Russia: 1 adult male, Chukotka Peninsula, Kresta Bay, Seutakan Lake , 11.IX.1984, leg. V. Bogatov .

Adult male (n = 1).

Total length 4 mm. Wing length 3.12 mm. Total length/wing length 1.3.

Coloration. Thorax, legs, and abdomen dark brown, wings greyish.

Head destroyed.

Thorax. Antepronotum with 5 ventrolateral setae. Acrostichals absent, dorsocentrals 11, prealars 4, scutellars 17.

Wing. Length 3.12 mm; width 1.0 mm. R and R 1 with 13 setae; R 4+5 with 5 setae in distal part. Costal extension 80 µm long. RM length/MCu length 3.3. Anal lobe developed, rounded-angular. Squama with 33 setae.

Legs. Spur of front tibia 60 µm long. Both spurs of mid tibia 44 µm long. Spurs of hind tibia 68 µm and 52 µm long.

Apex of ta 1 –ta 3 of all legs with 2 pseudospurs. About 7 pseudospurs sit along the entire length of the ta 1 of the mid leg, and on the hind leg pseudospurs cover surface of ta 1 and ta 2. Hind tibial comb with 15–19 setae. Length (μm) and proportions of leg segments are as in Table 2.

Hypopygium ( Figs. 5–6 ). Tergite IX with 14–17 setae and anal point 156 μm long. Anal point with rod-shaped setae apically. Laterosternite IX with 9–11 setae. Gonocoxite 308 μm long, with wide and flat inferior volsella; basimedial cluster with 6–7 setae, 48–52 μm long. Gonostylus 156 μm long, greatly widens distally, with angular heel, in apical part with megaseta 8 μm long and tooth. HR 1.34–1.57.

Pupa and larva unknown.

Remark. I have synonymized D. bogatovi with D. nivoriunda with some hesitation due to the small amount of material. In the future, after getting of additional material, it will be necessary one more time to compare North American specimens with Chukotka population.

Distribution. Before finding in Chukotka Peninsula was known only from North America ( Hansen & Cook 1976).

Figures

FIGURES 1–6. Adult males of Diamesa tsutsuii Tokunaga (1–4) and D. nivoriunda (Fitch) (5–6). 1, antenna; 2, total view of hypopygium from above; 3, 5, part of hypopygium from above; 4, 6, part of hypopygium from below.