Diamesa soktoshensis Makarchenko, Semenchenko et Palatov, 2025

Diamesa soktoshensis Makarchenko, Semenchenko et Palatov , sp. nov.

http://zoobank.org/NomenclaturalActs/ C1741C34-32D5-417E-B459-31D7C030CCFC

( Figs 2 View FIGURES 1–7 , 12 View FIGURES 8–14 , 27–28 View FIGURES 27–30 )

Type material. Holotype, adult male, TAJIKISTAN: Gorno-Badakhshan Autonomous Region, Roshtkalinskiy District, Soktosh River , about 2.3 km to West from Deruzh Stronghold , alt. 3343 m a. s. l., 02.VII.2016, 37.3786 N 72.3493 E, leg. D. Palatov. GoogleMaps Paratypes: 3 adult males, the same data as holotype GoogleMaps .

Derivatio nominis. The species is named as soktoshensis after the type locality in the Soktosh River in Pamir.

Description

Adult male (n = 2, except when otherwise stated). Total length 3.0– 3.5 mm. Total length/wing length 0.93– 1.15.

Coloration. Dark brown to black. Head, thorax and abdomen dark brown to black. Legs black. Wings greyish, with brownish veins.

Head. Eyes hairy, reniform. Temporal setae including 5 frontals, 11 verticals. Clypeus with 10 setae. Antenna with 13 flagellomeres and reduced plume of setae ( Fig. 2 View FIGURES 1–7 ); number and length of these setae on 1–12 flagellomeres respectively: 1 (68 μm), 3 (112 μm), 3 (128–164 μm), 5 (200 μm), 5 (96–200 μm), 5 (84–96 μm), 5 (90–200 μm), 5 (120–160 μm), 5 (100–200 μm), 5 (160–200 μm), 5 (96–164 μm), 5 (100–200 μm); terminal flagellomere with 9 setae, 88–112 μm long in basal part and with 1 subapical setae, 32–40 μm long. Length of 1–13 flagellomeres (μm): 84–92, 48, 48–52, 52–60, 52, 52, 52–56, 52–60, 48, 52–56, 52–56, 52–56, 236–272; AR 0.37–0.40. Palpomere length (μm): 44, 92, 148, 156, 208. Palpomere 3 in distal part with sensilla capitata with diameter 20 μm. Head width/palpal length 1.04. Antennal length/palpal length 1.38.

Thorax. Antepronotum with 4–6 ventrolateral setae, 44–52 μm long. Dorsocentrals 9–11, 56–72 μm long; prealars 5–7, 48–60 μm long. Scutellum with ca 30 setae.

Wing ( Fig. 12 View FIGURES 8–14 ). Length 3.0– 3.2 mm, width 0.92–0.96 mm. Costal extension 49–66 µm long. Anal lobe rounded-angular. Squama with 20–23 setae, 104–124 μm long. R and R 1 with 33 setae, R 4+5 with 13 setae. RM/MCu 2.6.

Legs. Spur of front tibia 60–68 µm long. Spurs of mid tibia 52–56 µm and 40–48 µm long. Spurs of hind tibia 84–88 µm and 48 µm long. Hind tibial comb with 17–19 setae. Length (μm) and proportions of leg segments are as in Table 6.

Hypopygium ( Figs 27–28 View FIGURES 27–30 ). Tergite IX with 16–19 setae, 80–100 µm long and with narrow naked anal point, 80–88 µm long. Laterosternite IX with 8–10 setae, 88–100 µm long. Transverse sternapodeme 124 µm long, 52 µm wide. Gonocoxite 476 µm long; inferior volsellae 200 µm long, expanded basally and finger-shaped distally, with numerous medium-length setae along the inner edge; basimedial setal cluster with 26–28 setae, 188–200 µm long. Gonostylus 312 µm long, slightly curved, widened in basal two-thirds and narrow in distal third, megaseta 8 μm long, next to it there is tooth. HR 1.53.

Pupa and larva unknown.

Diagnosis. Total length 3.0– 3.5 mm, wing length 3.0– 3.2 mm. Eyes hairy, reniform. Clypeus with 10 setae. Antenna with 13 flagellomeres and reduced plume of setae ( Fig. 2 View FIGURES 1–7 ); AR 0.37–0.40. Head width/palpal length 1.04. Antennal length/palpal length 1.38. Anal lobe rounded-angular. Dorsocentrals of mesonotum 9–11, prealars 5–7, scutellars ca 30. Squama with 20–23 setae. Hind tibial comb with 17–19 setae. Tergite IX with 16–19 setae, 80–100 µm long and with narrow naked anal point, 80–88 µm long. Transverse sternapodeme 124 µm long, 52 µm wide. Inferior volsella 200 µm long, expanded basally and finger-shaped distally, with numerous medium-length setae along the inner edge; basimedial setal cluster with 26–28 setae, 188–200 µm long. Gonostylus slightly curved, widened in basal two-thirds and narrow in distal third, megaseta 8 μm long, next to it there is tooth. HR 1.53.

Ecology. Adult males were collected from the Soktosh River, which flows through a shallow, semi-desert mountainous valley at an altitude of 3343 m above sea level. The width of the river is 3.5–4 m, the substrate consists of stones, boulders, with scattered pebbles and sand. At the time of collection in July, the flow rate of the river was 0.3–1 m /s, and the water temperature 7°C.

Distribution. Known only from the type locality in the Pamir Mountains ( Figs 35–36 View FIGURES 35–36 ).