Cyphomella cana ( Strobl, 1910 )

Orel, Oksana V., 2025, Redescription of Cyphomella cana (Strobl, 1910) (Diptera, Chironomidae) from the Russian Far East, Zootaxa 5661 (1), pp. 142-150 : 143-145

Cyphomella cana ( Strobl, 1910)

Figs 1–28 .

Chironomus canus Strobl, 1910: 266

Cyphomella cana ( Strobl, 1910) , Vallenduuk 2019: 167, Fig. 136

Cyphomella cornea Saether, 1977: 105 , Fig. 37 E–F; Langton & Visser 2003; Zorina 2006: 386; Moller Pillot 2009: 95 Material examined. 2 males, RUSSIA, SAKHALIN ISLAND, Poronaisky District, Leonidovka River 8 km below the village, 9–10.vii. 2001 (Makarchenko E.A.) ; 1 male, same data, Nogliki district, Rybnoe Lake , 27.vii.2002 (Makarchenko E.A.) ; 1 male, same data, Tym River 2 km from the automobile bridge over the Parkata River , 02.viii.2003 (Makarchenko E.A.) ; 6 males, same data, Dolinsky district, “Sokol” biological station, Belaya River , 19–20.viii.2003 (Makarchenko E.A.) ; 1 male, AMUR REGION, Selemdzha river basin, Aldikon River near the of Norsk Town , 16.vi.2004 (Tiunova T.M.); 1 mature pupa with larval exuviae, Zeya river basin, Bolshaya Pera River , 14.ix.2021 (Yavorskaya N.M.) ; 2 male, JEWISH AUTONOMOUS REGION, Amur River, Petrovskaya channel, 123rd km, 01.vii.2006 (Yavorskaya N.M.) ; 1 male, KHABAROVCK TERRITORY, Verkhnebureinsky district, Bureya river basin, Urgal River 4 km from the mouth, 21.ix.2006 (Tiunova T.M.); 1 mature pupa, Amur River , lower course, 05.vi.2018 (Yavorskaya N.M.) ; 1 immature pupa, Amur River basin, Tunguska River , 05.vi.2018 (Yavorskaya N.M.) ; 5 males, Anyuisky National Park, Amur River basin, Troitskoye village , unnamed stream near the ANP office, 26.v.2019 (Yavorskaya N.M.) ; 1 male Komsomolsky Nature Reserve, Beach-Khauni Lake , 21.v.2020 (Yavorskaya N.M.) .

Diagnosis. Male: dark brown coloured species, with wing 1.91–2.40 mm long and AR 1.63–1.94; LRPI 1.40–1.51; anal point narrow, apically widened and rounded; superior volsella with 4–7 setae and microtrichia on ventromedian margin; membranous apical part of the superior volsella may be curved dorsally; inferior volsella without setae. Pupa: total body length 3.0– 4.4 mm; cephalic tubercles 75–84 μm long; Pedes spurii B on segment II present, hook rows with 59–71 hooks, sometimes narrowly interrupted medially and with a group of hooks medially. Larva: AR 1.36; antenna blade length 42 µm; mandible with light apical and three inner teeth; the first lateral teeth of the mentum are light.

Description. Adult male (n = 6)

Body size and proportions. Total length 3.2–3.8 mm. Wing length 2.12–2.40 mm. Total length/wing length ratio 1.45–1.58.

Colouration. Antenna and palps brown. Scutal vittae, scutellum and postnotum brown, ground colour of thorax and haltere yellow brown, legs and abdomen brown.

Head. Antenna 1020–1060 μm long; ultimate flagellomere 660–700 μm long; AR 1.65–1.94. Frontal tubercles subcylindrical/conical with round apex, 15–21 μm long, 9–15 μm wide ( Fig. 1 ). Temporal setae 12–16 on each side. Clypeus with 8–14 setae. Lengths of 2–4 palpomeres (in μm): 48–54, 144–152, 136–160, 200–240.

Thorax. Aps 5–9, Ac absent, Dc 5–9 on each side, uniserial; Pa 2–4 on each side; Scts 8–12.

Wing 0.58–0.68 μm wide. R with 6–10 setae, R 4+5 with 2–7 setae (of which 2 are apical). Brachiolum with 2 setae; squama with 6–11 setae. VR 1.0–1.2.

Legs. Tibial combs of mid and hind legs fused, with straight spur: 18–24 (mid leg) and 24–30 μm long (hind leg). Basitarsus of mid leg with 2–6 sensillum chaeticum (n=6).

Lengths and proportions of legs as in Table 1.

Hypopygium ( Figs 2–8 ). Tergite IX reticulated; with 8–12 setae on each side of anal point (2–4 setae may be located at the base of the anal point), tergite bands weakly expressed; laterosternites with 2–5 setae on each side. Anal point narrow, apically widened and rounded (69–81 μm long, 15 μm wide apically). Gonocoxite 105–135 μm long, with 3–4 setae along the inner margin. Phallapodeme 84–114 μm long; transverse sternapodeme 60–81 μm long. Superior volsella 42–60 μm long, with 4–7 setae and microtrichia on ventromedian margin; membranous apical part of the superior volsella may be curved dorsally. Inferior volsella without setae. Gonostylus 141–165 μm long, widened in the proximal part and gradually narrows apically. HR 0.7–0.9.

Pupa (n = 3) 3.0– 3.3 mm long.

Cephalothorax. Frontal tubercles well-developed, conical, 75–84 μm long, 36–45 μm wide at base ( Fig. 9 ). Frontal setae short (18–24 μm long) located subapically. Thorax granulose along median suture ( Fig. 10 ). Antepronotals 2 (median (105 μm long and lateral (120 μm long), taeniate). Precorneals 2 (60–75 μm long, taeniate). Dc 1–4 simple, 30–45 μm long. Distance between Dc 1 and Dc 2 27–30 μm, Dc 3 and Dc 4 12–24 μm, Dc 2 and Dc 3 141–144 μm. Wing sheath 1000–1100 μm long. Prealar tubercle well-developed.

Abdomen ( Figs 11–16 ) 2.7 mm long. Hook rows with 59–68 hooks, 336 μm wide, narrowly interrupted medially and with group of hooks medially. Tergite I bare; II–VI with median shagreen: weak anteromedian spines grading over into stronger posterior spines; VII in proximal part with transverse stripe of shagreen; VIII with anterolateral patches of shagreen. Sternite II–III with a medial longitudinal strip of shagreen; IV with a medial triangular strip of shagreen; V without of shagreen; VI–VIII with anterolateral patches of shagreen. Segment VIII with 5–12 strong dark spurs (6–30 μm long) ( Figs 15–16 ). Segment II–IV with 3 L setae, V with 3 LS setae, VI–VII with 4 LS setae, and VIII with 4 (rarely 5) LS setae. Anal lobe well developed with two patches of shagreen and complete fringe of 38–50 taeniate setae. Anal segment 168–210 μm long and 195–270 μm wide, with shagreen.

Figures

FIGURES 1–8. Details of the structure of the male imago Cyphomella cana (Strobl, 1910). 1—frontal tubercles; 2–3, 5— hypopygium, dorsal view; 3, 6–8—superior volsella. Scale bar 50 μm.

FIGURES 9–16. Details of the structure of the pupa Cyphomella cana (Strobl, 1910). 9—frontal tubercles; 10—thorax, lateral view; 11—tergite II; 12—tergites III; 13—tergite V; 14—tergites VIII–IX; 15–16—anal comb. Scale bar 20 μm (10–14) and 50 μm (9, 15–16).

FIGURES 17–22. Details of the structure of the larva Cyphomella cana (Strobl, 1910). 17—setae S 3; 18—labrum; 19— antenna; 20—mandible; 21—mentum and ventromental plates; 22—posterior parapods and procerci; Scale bar 20 μm (22) and 50 μm (17–21).

FIGURES 23–28. Details of the structure of the larva Cyphomella cana (Strobl, 1910). 23—labrum; 24—sclerite 1, clypeus and frontal apotome; 25—antenna; 26—mandible; 27—maxillary palp; 28—mentum and ventromental plates. Scale bar 50 μm.