Propsilocerus paradoxus (Lundström)

Makarchenko, Eugenyi A. & Semenchenko, Alexander A., 2023, Review of subfamily Prodiamesinae (Diptera: Chironomidae) from the Russian Far East and bordering territory, Zootaxa 5323 (1), pp. 1-26 : 15-19

Propsilocerus paradoxus (Lundström)

( Figs. 40–48 )

Orthocladius paradoxus Lundstrȍm, 1915: 14 .

Synpropsilocerus paradoxus Kieffer 1923: 3 .

Syndiamesa komensis Zvereva, 1950: 275 ; Pankratova 1970: 75.

Propsilocerus paradoxus (Lundstr̂m); Saether & Wang 1996: 469; Petrova et al. 2003: 36; Saether 2004: 17 ; Makarchenko & Makarchenko 2006: 349; Ashe & O’Connor 2012: 502.

Material examined. Russia: 2 adult males, Eastern Siberia, Trans-Baikal Territory, Chita City , Kenon Lake , 1.V.2003, 52.030147 N, 113.380136 E, leg. О. Klishko ; 4 adult males, Jewish Autonomous Region, Smidovichsky District, Nature Reserve “Bastak”, Zabelovskoye Lake , 48.432583 N, 134.213889 E, 16.IV.2008, leg. V. Lubarets ; 2 adult males, Republic of Buryatia, Selenginsky District, Gusinoe Lake , 20.V.2017, leg. N. Bazova.

Comments. Some variation is added based on the males from the Russian Far East.

Description

Adult male (n = 4, except when otherwise stated). Total length 4.2–6.2 mm (n = 11). Total length/wing length 1.24–1.36.

Coloration (slide-mounted material). Head, thorax, tergites of abdomen dark brown; legs brown ot yellowishbrown; hypopygium brown; wings grayish.

Head. Eyes bare, reniform. Temporal setae including 2–3 verticals and without postorbitals. Clypeus with ca 50–70 setae. Antenna with 13 flagellomeres and developed plume; terminal flagellomere with 3 sensitive setae, 20–36 μm long; AR 2.25–2.33. Palpomeres lengths (in μm): 20–40; 68–73; 152–160; 92–100; 100–108. Palpomeres 1–5 length/head width 1.68–1.74.

Thorax. Antepronotum with 13–21 lateral setae. Acrostichals absent, dorsocentrals 60–84 (in anterior part in 2–3 rows, in posterior in 4–6 rows), prealars 6–11 scutellars 21 – 28 (in 1–2 rows);

Wing. Length 3.4–4.1 mm, width 0.84–1.2 mm. R with 8 setae, R 1 and R 4+5 with 0 setae. Costa extension 120–190 μm long. RM length/MCu length 1.22–1.3. Anal lobe developed, outline rounded. Squama with 27 setae 72–92 μm long. VR 1.0–1.1.

Legs. Spur of fore tibia 84–96 μm long; spurs of mid tibia 56–60 μm and 64–72 μm; of hind tibia 56–62 μm and 72–92 μm long. Lengths and proportions of leg segments as in Table 7 .

Hypopygium ( Figs. 40–48 ). Tergite IX with 102–122 setae and tapering to pointed apex anal point 68–132 μm long; with 5–7 lateral setae, 36–48 μm long ( Figs. 46–48 ). Laterosternite IX with 9–12 setae. Phallapodeme 129–180 μm long; transverse stemapodeme 208–264 μm long, slightly concave, with oral projections ( Fig. 43 ). Gonocoxite 590–804 μm long. Inferior volsella as in Figs. 40–41 ), 400–432 μm long. Median volsella with 2–7 strong setae 64–100 μm long on small tubercle ( Figs. 42, 45 ). Gonostylus with two branches, basal branch 188–246 μm long; megaseta 8 μm long ( Figs. 40, 44 ). HR 3.28 –4.9.

Remarks. Comparison of males from the Russian Far East with males from other populations showed that they are similar in main characters, except for a greater number of dorsocentrals (60–84), a longer anal point (68–132 μm) and a transverse sternapodeme (208–264 μm). Specimens from China have 36–73 dorsocentrals, the length of anal point is 40–79 µm, and length of transverse sternapodeme is 120–184 µm ( Table 8 ).

Distribution. Reliably known from China, Mongolia, East Siberia and Russian Far East.

Figures

FIGURES 40–48. Adult males of Propsilocerus paradoxus (Lundstrṏm). 40, part of hypopygium in dorsal view; 41, part of hypopygium in ventral view; 42, 45, median volsella; 43, transverse sternapodeme, phallapodeme and aedeagal lobe; 44, gonostylus; 46–47, tergite IX; 48, anal point. Scale bar is 50 μm.