Stempellinella tamaseptima ( Sasa, 1980 )

Orel, Oksana V., 2023, Stempellinella Brundin, 1947 (Diptera: Chironomidae) from Eastern Siberia and the Russian Far East, with the description of new species, Zootaxa 5380 (4), pp. 341-360 : 356-358

Stempellinella tamaseptima ( Sasa, 1980)

Figs 47–51 .

Tanytarsus tamaseptimus Sasa, 1980: 22 , Figs 20–22 .

Stempellinella tamaseptima ( Sasa, 1980) , Kobayashi 1990: 5; Ekrem 2007: 1443 , Fig. 28 ; Orel 2016: 194; Makarchenko & Orel 2023: 145.

M aterial examined. RUSSIA: KHABAROVSK TERRITORY, Amur river basin, Yai River near the bridge, 30.vii.2005, 1 male, leg. E. Makarchenko ; SAKHALIN REGION, Sakhalin Island, Tymovsky district, the Tym River in the region of the mushroom cooker, 27.vii.2003, 1 male, leg. E. Makarchenko.

Diagnosis. Male: yellowish coloured species, with wing 0.80–1.33 mm long. AR 0.56–0.96; ultimate flagellomere 312–328 μm; length of 2–4 flagellomeres of maxillary palpomeres 294–315 μm; frontal tubercles conical, 9–18 μm long; LR PI 1.42–1.77; combs of mid and hind tibiae with 1 long spur. Anal tergite with transverse anal tergite band; 4–5 strong median setae; lateral setae absent; anal point with strong spinulae at base; superior volsella rectangular; median volsella elongated, with 7–10 lamellae and microtrichia.

Redescription. Adult male (n=2). General colour yellowish. Total length 1.6 mm; total length/wing length 1.33.

Head ( Fig. 47 ). Frontal tubercles conical, 12–18 μm long. Temporal setae 7–8. Clypeus with 10–11 setae. Maxillary palp yellow, 294–315 μm long; lengths of last 4 palpal segments (μm): 30, 63–72, 87–90, 114–123. Scapus yellowish brown, flagellomeres (1–10) dark-brown, 640–688 μm long. AR 0.91–0.95. Ultimate flagellomere 312–328 μm long. Antenna length/palp length 2.18.

Thorax. Ground colour of scutum yellowish, mesonotal strips yellowish brown or brown. Ac 8–11, Dc 5–8, Pa 1. Scutellum brownish, with 5–6 setae. Postnotum brown.

Wing ( Fig. 48 ) length 1.20 mm. R, R 1 with 37 setae, R 4+5 with 24 setae, Cu 1 with 12 setae, M 3+4 with 15 setae, Cu with 13 setae, An with 15 setae. VR 1.34.

Legs ( Table 7 ). Legs yellow. Fore tibia with 12 mm long spur; terminal combs of Ti 2 and Ti 3 with 1 spur, 18 μm long. BR 1 3.6, BR 2 6.3, BR 3 6.4. Sensilla chaetica on Ta 1 P 2 absent.

Abdomen. Yellowish.

Hypopygium ( Figs 49–51 ). Anal tergite with transverse anal tergite band; 4–5 strong median setae; lateral setae absent; small microtrichia-free areas present on each side of anal point base.

Anal point 24–30 μm long, wide at about apical 1/3, apically thin and pointed; 8–13 strong spinulae between well-developed anal crests; 7–8 lateral setae at anal point base. Gonocoxite 63–69 μm long; with 4 setae along inner margin. Width of transverse sternapodeme 42–45 μm. Phallapodeme 54 μm long. Superior volsella rectangular, 30–33 μm long, with 3–4 dorsal and 3 median setae, without microtrichia. Digitus absent. Median volsella elongated (39–45 μm long), with 7–10 lamellae and microtrichia. Inferior volsella 54–60 mm long, apically slightly club-shaped, with 4–5 setae. Gonostylus 45 μm long, with 2–4 setae in apical part and 1 apical seta. HR 1.40–1.53.

Female described by Ekrem 2007: 1446, Fig. 28 F, G .

Pupa described by Sasa 1980: 22, Fig. 22 , Ekrem 2007: 1446.

Larva unknown.

Remarks. When comparing the morphometric data of males described in Sasa (1980), Ekrem (2007) and our data, no significant differences were found (see Table 8 ).

Distribution. Canada, Japan and Russian Far East ( Ekrem 2007; Makarchenko & Orel 2023).

Figures

FIGURES 47–51. Details of the structure of the male of Stempellinella tamaseptima (Sasa, 1980). 47—head; 48—wing; 49– 50—hypopygium; 51—superior and median volsellae, dorsal view. Scale bar 20 µm (47–49), 50 µm (50–51).

FIGURES 17–20. Details of the structure of the pupa of Stempellinella chirka sp. nov. 17—frontal apotome; 18—thorax, lateral view; 19—tergites I–V; 20—tergites VI–IX. Scale bar 20 µm.

FIGURES 21–25. Details of the structure of the pupa of Stempellinella chirka sp. nov. 21—frontal tubercles; 22—thorax, lateral view; 23—tergites II–III; 24—tergites VI–VII; 25—tergite VIII. Scale bar 50 µm.

FIGURES 26–34. Details of the structure of the larva of Stempellinella chirka sp. nov. 26, 31A—antenna; 31B—antennal pedestal with spur; 27–28—labrum; 29, 33—mandible; 30, 34—mentum and ventromental plates; 32—premandible. Scale bar 20 µm (26–30), 50 µm (31–34).

Tables

TABLE 7. Length (μm) and proportions of legs of the male Stempellinella tamaseptima (Sasa, 1980) (n=1)

P	Fe	Ti	Ta1	Ta2	Ta3	Ta4	Ta 5
P 1	464	304	480	280	224	168	80
P2	544	416	248	104	88	64	56
P3	584	456	344	176	152	88	64
P	LR	SV	BV
P1	1.58	1.60	1.66
P 2	0.59	3.87	3.87
P3	0.75	3.02	2.88