Stempellinella coronata Inoue, Kawai et Imabayashi, 2004

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 : 351-354

Stempellinella coronata Inoue, Kawai et Imabayashi, 2004

Figs 35–40 .

Stempellinella coronata Inoue, Kawai et Imabayashi, 2004: 141 , Fig. 2–5 ; Ekrem 2007: 1401 , Fig. 11 ; Makarchenko & Orel 2023: 145.

Stempellinella ministylus Ree, 2015: 240 , Fig. 11 . syn. nov.

Material examined. RUSSIA: PRIMORYE TERRITORY, Kirovsky district, Ussuri river basin, Sungacha River near the mouth of the Belaya River , 16.v.2004, 1 male, leg. E. Barabanschikov ; KHABAROVSK TERRITORY, the Kiya River below the village of Ekaterinovka , 09.vi.2004, 11 males, leg. T. Tiunova; Bolshekhekhtsirsky nature reserve, Golovin Stream , 13.vi.2015, 1 male, leg. N. Yavorskaya.

Diagnosis. Male: yellowish coloured species, with wing 0.68–1.02 mm long and AR 0.48–0.73; ultimate flagellomere 208 μm; length of 2–4 flagellomeres of maxillary palpomeres 219–225 μm. LR PI 1.93–2.22. Combs of mid and hind tibiae with 2 spurs. Anal tergite with transverse anal tergite band; lateral seta absent; anal point with numerous small spinulae between anal crests; small median tergite setae at anal point base 0–2; superior volsella oval, with 3–5 dorsal and 2–3 median setae; median volsella strongly curved, apically widened with 10 setae, without microtrichia, stem of median volsella 39–45 μm long; inferior volsella reaches to apex of gonostylus.

Redescription. Adult male (n=3). General colour yellowish. Total length 1.2–1.3 mm; total length/wing length 1.13–1.30.

Head ( Fig. 35 ). Frontal tubercles minute or absent. Temporal setae 4. Clypeus with 10–13 setae. Maxillary palp yellow, 219–225 μm long, lengths of last 4 palpal segments (μm): 18–21, 45–51, 69–75, 84. Palp length/head width 1.33–1,57. Scapus yellowish brown, flagellomeres (1–10) brown, 552–576 μm long. AR 0.59–0.60. Ultimate flagellomere 208 μm long. Antenna length/palp length 2.52–2.56.

Thorax. Ground colour of scutum yellow, mesonotal strips yellowish brown.Ac 10–12, Dc 5–7, Pa 1. Scutellum yellowish brown, with 4–6 setae. Postnotum brown.

Wings ( Fig. 36 ) length 1.00– 1.02 mm. R, R 1 with 27–30 setae, R 4+5 with 20–24 setae, Cu 1 with 11–19 setae, M 3+4 with 7–14 setae, Cu with 14–19 setae, An with 15–20 setae. VR 1.45–1.55.

Legs ( Table 4 ). Legs yellowish. Fore tibia with 12–15 mm long spur; terminal combs of Ti 2 and Ti 3 with spurs, 15 μm long. BR 1 3.0, BR 2 4.2–4.6, BR 3 4.7–5.0. Sensilla chaetica on Ta 1 P 2 absent.

Abdomen. Pale yellow.

Hypopygium ( Figs 37–40 ). Anal tergite with transverse anal tergite band; 0–2 small median setae present at anal point base; lateral setae absent; small microtrichia-free areas present on each side of anal point base. Anal point strong and long (33–39 μm), wide at about apical 1/3, apically thin and pointed; with numerous small spinulae between anal crests; 7–8 lateral setae at anal point base. Gonocoxite 60–63 μm long; with 2–3 setae along inner margin. Width of transverse sternapodeme 36–39 μm. Phallapodeme 45 μm long. Superior volsella oval 24–27 μm long, with 3–5 dorsal and 2–3 median setae, without microtrichia. Digitus absent. Median volsella 54–60 μm long strongly curved posteriorly, apically expanded (in lateral view) with 8–10 simple setae; stem of median volsella 39–45 μm long, without microtrichia. Inferior volsella 42–45 mm long, slightly curved inward, extending to apex of gonostylus, with 5–6 setae. Gonostylus short, 30–39 μm long, with 2–3 setae in apical part and 1 apical seta. HR 1.6–2.0.

Female described by Ekrem 2007: 1402, Fig. 11 B, C .

Pupa and larva unknown.

Remarks. The males of Stempellinella ministylus Ree, 2015 described from South Korea ( Ree 2015: 240, Fig. 11 ) have identical hypopygium structure with Stempellinella coronata Inoue, Kawai et Imabayashi, 2004 from Japan. After a comparative morphometric analysis (according to the literature data) of these two species, we came to the conclusion that Stempellinella ministylus Ree is a junior synonym of Stempellinella coronata Inoue, Kawai et Imabayashi (see Table 5 ).

Distribution. Japan, Korea and Russian Far East ( Inoue, Kawai & Imabayashi 2004; Ree 2015; Makarchenko & Orel 2023).

Figures

FIGURES 35–40. Details of the structure of the male of Stempellinella coronata Inoue, Kawai et Imabayashi, 2004. 35—head and antenna; 36—wing; 37–38, 40—hypopygium; 39—superior and inferior volsellae, dorsal view. Scale bar 20 µm (35–38), 50 µm (39–40).

FIGURES 1–7. Details of the structure of the male of Stempellinella bazovae sp. nov. 1—head and antenna; 2—wing; 3–5— hypopygium; 6—superior volsella, dorsal view; 7—superior, median and inferior volsellae, dorsal view. Scale bar 20 µm (1–4), 50 µm (5–7).

FIGURES 8–16. Details of the structure of the male of Stempellinella chirka sp. nov. 8—head; 9—antenna; 10—wing; 11, 15—hypopygium, dorsal view; 12, 14—hypopygium, ventral view; 13—hypopygium, lateral view; 16—superior, median and inferior volsellae, dorsal view. Scale bar 20 µm (8–14), 50 µm (15–16).

Tables

TABLE 4. Length (μm) and proportions of legs of the male Stempellinella coronata Inoue, Kawai et Imabayashi (n=3)

P	Fe	Ti	Ta 1	Ta 2	Ta 3	Ta 4	Ta 5
P1	360–376	208–216	432	184	144	104	64
P2	440–472	328–336	192	72	56	48	48
P 3	480–488	360–384	264–256	112–120	112–120	72	56–64
P	LR	SV	BV
P 1	2.08	1.31	2.02
P2	0.57–0.59	4.00–4.21	4.29–4.46
P3	0.67–0.73	3.18–3.41	2.96–3.07

TABLE 5. Comparative morphological characteristics of the males of Stempellinella coronata Inoue, Kawai et Imabayashi and Stempellinella ministylus Ree.

Characters	Stempellinella coronata Inoue, Kawai et Imabayashi (from Inoue, Kawai & Imabayashi 2004; Ekrem 2007)	Stempellinella ministylus Ree ( Ree 2015)	Stempellinella coronata Inoue, Kawai et Imabayashi (our data)
Total length, mm	1.10–1.30	-	1.2–1.3
Wing length, mm	0.68–0.84	0.93	1.00–1.02
Frontal tubercles length, µm	minute	absent	minute
AR	0.48–0.73	0.59	0.59–0.60
Ac	9–12	10	10–12
Dc	6–7	7–9	5–7
Scts	4–6	3	4–6
LR PI	1.93–2.22	2.17	2.08
Median setae on tergite IX	0–2	0	0–2