Diamesa tsutsuii Tokunaga

Diamesa tsutsuii Tokunaga View in CoL

( Figs 6 View FIGURES 1–7 , 14 View FIGURES 8–14 , 33–34 View FIGURES 31–34 )

Diamesa tsutsuii Tokunaga, 1936: 546 View in CoL ; 1964: 22; Makarchenko 1977: 113, 1985: 82; 2006: 261, 477, 614; 2023: 144; Linevich & Makarchenko 1989: 32; Ashe & O’Connor 2009: 287; Makarchenko & Makarchenko 2017: 130.

Diamesa coquilletti Sublette, 1966: 584 View in CoL ; Hansen & Cook 1976: 78.

Diamesa matuimpedita Sasa, 1989: 149–150 View in CoL .

Material examined. JAPAN: 1 adult male ( holotype), Nagano Prefecture, Hosono , from snow, alt. 600 m above sea level, 17.III.1935, leg. K. Tsutsui. 15 adult males, 5 pupae, 11 larvae, RUSSIA: Primorye Territory, Khasansk District, Kedrovaya Pad Nature Reserve , Kedrovaya River , 15–17.II.1975, leg. E. Makarchenko ; 1 adult male, Ternei District, Sikhote-Alin Nature Reserve, Spornyi Stream ( Serebrianka River basin), leg. O. Zorina ; 12 adult males, 6 pupae, 14 larvae, Jewish Autonomous Region, Obluchie District, Bidzhan River , ( Amur River basin), from snow, 27.III.2013, 48.640150 N, 131.620283 E, leg. E. Makarchenko GoogleMaps ; 5 adult males, Khabarovsk Territory, Nanaisky District, Anyuisky National Park , Pihtsa River (tributary of Gassi Lake ), Amur River basin, 25. V 2019, leg. N. Yavorskaya ; 2 adult males, Magadan Region, Olskyi District, Ola River , 29.IV.2014, leg. E. Khamenkova , 2 adult males, the same data except 3. V.2019, leg. E. Khamenkova ; 3 adult males, 3 pupae, Sakhalin Island, Yuzhno- Sakhalinsk City, Bereznjaki River , 17.IV.2015, leg. E. Zhivogliadova.

Description

Adult male (n = 7). Total length 4.3–6.2 mm. Total length/wing length 1.33–1.35.

Antenna with 8 flagellomeres and reduced plume of setae ( Fig. 1 View FIGURES 1–7 ); number and length of these setae on 1–7 flagellomeres respectively (n=2): 2–3 (36–40 μm), 1 (40–42 μm), 3–4 (56–60 μm), 3–4 (48–56 μm), 3–4 (48–56 μm), 2–3 (80–82 μm), 2–3 (80–82 μm); terminal flagellomere with 3–4 setae, 72–80 μm long in basal part and with 1 subapical setae, 20–22 μm long. Length of 1–8 flagellomeres (μm) (n=4): 76–84, 52–56, 60–64, 48–56, 52–56, 42–44, 38–44, 156–164; AR 0.40–0.50. Palpomere length (μm): 46–48, 55–100, 134–140, 143–152, 212–220. Head width/palpal length 1.05–1.06. Antennal length/palpal length 0.80–0.84. Thorax. Antepronotum with 9–11 ventrolateral setae. Dorsocentrals 10–13, prealars 6–10. Scutellum with 20–42 setae. Wing 3.2–4.0 mm long. Anal lobe rounded-angular. LR 1 0.54–0.62, BV 1 3.48–4.04, SV 1 3.0–3.48.

Hypopygium ( Figs 33–34 View FIGURES 31–34 ). Tergite IX with 12–24 setae and anal point, 124–164 μm long, ca 40 μm wide, which slender apically, broadening basally, usually does not go beyond top of proctiger or only slightly goes. Laterosternite IX with 10–11 setae. Transverse sternapodeme trapezoidal, without antero-lateral projections, 204–280 μm long, 44–52 μm wide. Gonocoxite 400–508 μm long; inferior volsella ca 260 μm long, basal half widened, narrow distal, with setae along inner margin, which are longest in basal part; basimedial setal cluster absent. Gonostylus 280–360 μm long, curved, widened and rounded in basal third, narrow in distal two-thirds, with megaseta 32–36 μm long. HR 1.40–1.43.

Pupa and larva. Described by Makarchenko (1985, 2023).

Distribution. East Palaearctic species. The western border of the range is the basin of Baikal Lake.