Constempellina brevicosta Edwards 1937

Constempellina brevicosta (Edwards, 1937)

(Figs 31–43)

Tanytarsus (Phaenopelma) brevicosta Edwards, 1937: 146, fig. 2.

Lauterbornia (Phaenopelma) brevicosta Edwards; Goetghebuer (1940: 57).

Stempellina septentrionalis Tshernovskii, 1949: 47 (synonymized by Shilova 1976).

Stempellina ranota Webb, 1969: 91, figs 15–26 (according to Saether & Spies 2004).

Phaenopelma brevicosta Edwards; Thienemann (1941: 236, figs 45–47); Goetghebuer (1954: 137).

Constempellina brevicosta Edwards; Brundin (1947: 82, fig. 122); Brundin (1948: 19, figs 2, 7, 10, 15, 17); Shilova (1976: 18); Grimås & Wiederholm (1979: 119); Pankratova (1983: 27, fig. 8); Pinder & Reiss (1983: 306, fig. 10.9 A–E); Pinder & Reiss (1986: 313, fig. 10.10 A, B, D); Cranston et al. (1989: 369, fig. 10.11); Langton (1991: 314, figs 129 h–j); Gilka (2011: 33, figs 86–88).

Material. Three males, Sakhalin Island, Leonodovka River ca. 8 km of Leonidovka Village, 08.viii.2001, V. Teslenko; 15 males, same data, basin of Belaya River, stream at about 100 m of fish factory, 27.vi.1985, E. Makarchenko; 4 males, same data, Manuy River, 08.viii.2002, V. Teslenko; 1 male, Kamchatka Peninsula, Azabach’e Lake, 13–14.vii.1996, S. Belyanina; 3 males, same data, 14.vii.1996, R. Kuranishi; 7 males, Magadan Territory, Tauy River, 11.vi.2002, S. Kocharina; 2 males, same data, 16.vii.2002, S. Kocharina; 1 P-female, Kamchatka Peninsula, Bol’shaya River, 16.viii.2006, T. Travina; 5 males, Khabarovsk Territory, Nilan River, 23.vii.2006, E. Makarchenko; 1 male, Khabarovsk Territory, basin of Amur River, Kady River, upper reach, 2.vii.2005, E. Makarchenko; 3 males, Khabarovsk Territory, Chertovka River in 6 km of Lazarevo Village, 22.vi.2005, T. Tiunova; 1 male, Primorye Territory, Barabachevka River, 6.v.2003, T. Tiunova; 1 male, Primorye Territory, Sikhote-Alin Nature Reserve, Kolumbe River, 3.x.2005, O. Zorina.

Diagnostic characters. Wing length 1.5–2.0 mm; AR 1.0–1.26; anal point with short and conical apical part; basal part of superior volsella oval or triangular form, sometimes with a small tubercle. Pupa with bulb-shaped thoracic horn; tergite IV with posterolateral patches of spines; segment VIII with 4 strong anal spurs approximately equal length. Larva with setae SIII simple; pedestal with one apical tubercle; blade of antenna extending far beyond apex of 5th segment; AR 1.3 (according to Brundin 1948 and Pankratova 1983).

Male (n=12). Total length 2.3–3.1 mm; wing length 1.5–2.0 mm. Total length / wing length 1.31–1.63.

Colouration. Dark brown midges. Legs dark brown except for yellowish brown proximal half of the femur.

Head. Frontal tubercles well developed 15 µm long, 12 µm wide. Antenna 800–960 µm long; ultimate flagellomere 400–520 µm long; AR 1.0–1.26. Verticals 5–10. Clypeus with 11–17 setae. Maxillary palp 416–472 µm long; length of palpomeres 2–5 (in µm): 72, 104–120, 96–112, 144–184. Palp length / head width 0.96–1.04; antenna length / palp length 2.10–2.22.

Thorax chaetotaxy. Acrostichals 0–3, dorsocentrals 6–12, prealars 1. Scutellum with 2 setae.

Wing 0.4–0.5 mm wide (Fig. 31). Veins R+R1 with 24–57 setae, R4+5 with 4–34, M1+2 with 17–85, M3+4 with 24– 65, Cu1 with 7–18, Cu with 0–4 and An with 0–64 setae. Cells r4+5, m1+5, m3+4 with setae. VR 1.31–1.38.

Legs. Lengths and proportions of legs as in Table 2.

Hypopygium (Figs 32–37). Laterosternite IX with 1–5 strong setae. Apical part of anal point triangular (length 42–72 µm, width 12–15 µm at base), and with broad triangular base bearing 20–32 lateral setae (Figs 33–34). Gonocoxite 120–144 µm long, with 4–5 setae on inner margin. Superior volsella 30–39 µm long, apical part 9–18 µm long and with 3–4 setae, basal part oval (Fig. 37) or triangular form (Fig. 35), sometimes with a small tubercle (Fig. 36), bearing 1–7 setae and densely covered with microtrichia (rarely microtrichia absent Fig. 37). Median volsella 48–60 µm long with a dense clump of subulate setae. Inferior volsella 72–90 µm long, with 17–25 setae. Gonostylus 105–129 µm long, 30–39 µm wide at about middle, apically rounded.. HR 1.05–1.14.

Pupa (n=1, female). Cephalothorax (Figs 38–40). Cephalic tubercle conical, 36 µm long. Spine-like frontal setae 84 µm long. Thoracic horn 216 µm long, bulb-shaped, broadest basally (maximum width 69 µm), tapering to pointed apex, covered with small spines. Precorneals 3 (1st 126–144 µm long, 2nd 150–165 µm long, 3rd 144–156 µm long), antepronotals 2 (1 median 168 µm long and 1 lateral 105–120 µm long), dorsocentrals 4 (Dc1 84 µm long, Dc2 60 µm long, Dc3 144–150 µm long, Dc4 180–204 µm long); distance between Dc2 and Dc3 66 µm. Wing sheath with a well-developed “nose”.

Abdomen (Figs 21–43) 2.0 mm long. Tergites II–VI with pair of longitudinal bands of shagreen, broadened posterolaterally. Tergite IV in distal part with a pair of lateral patches each consisting of 18 spines. Tergite VII without shagreen. Tergite VIII medially with paired patches of very fine shagreen. Hook row 228 µm long with 90 spines. Pleura of segments V with shagreen. Pedes spurii B absent on segment II. Sternites IV laterally with paired longitudinal bands of pale spines connected medially. Lateral margin of segment VIII with 4 strong anal spurs approximately equal in length. Segments II–IV with a weak L seta, V–VII with 4 LS, and VIII with 2 LS setae. Anal lobe with 12–13 taeniate setae.

Fourth instar larva is absent in our materials. The brief description and illustrations of larva are given in articles of Brundin (1948), Pinder & Reiss (1983) and Pankratova (1983). Unfortunately, there are still no detailed morphometric descriptions of larvae of this species.

Remarks. The males of C. brevicosta are characterized by variability of morphological features such as chaetotaxy of the wing, AR, LR and structure of some parts of the hypopygium. Some variations are related to features of ecology of the species (Grimås & Wiederholm 1979), the other—with the incorrect identification of the species. Gilka (2011) gives a figure of the hypopygium of C. brevicosta which possibly most similar to C. arcticola sp. n. (Lindeberg unpublished data) in the form of anal point and gonostylus. Chaetotaxy of the wing was the most variable feature among the examined far eastern specimens of C. brevicosta (see redescription).

The male of C. brevicosta is similar to C. tokunagai sp. n., but can be separated by having an AR>0.9, anal point with short and conical apical part, basal part of superior volsella oval or triangular, sometimes with a small tubercle. The male of C. brevicosta is also similar to C. monticola (Lindeberg unpublished data), but it differs in the form of anal point and gonostylus. The pupa of C. brevicosta also closely resembles that of C. tokunagai sp. n., but may be separated by a bulb-shaped thoracic horn and by the presence of posterolateral patches of spines on tergite IV.

Morphological characteristics of the examined adult males and larvae of C. brevicosta agree with previous descriptions (Edwards 1937; Brundin 1947; Brundin 1948; Grimås & Wiederholm 1979; Pankratova 1983; Pinder & Riess 1983; Cranston et al. 1989; Lindeberg unpublished data). The far eastern pupae of C. brevicosta have two median patches of shagreen on tergite VIII, while pupae described by Thienemann (1941) and Webb (1969) are characterized by the presence of one median patch of shagreen.

Distribution and ecology. Constempellina brevicosta (Edwards) is distributed across the Holarctic Region (Saether & Spies 2004). This species was so far reported from various localities of the Northern part of European Russia (Zvereva 1969; Kuzmina 2001), Karelia (Zabolotsky 1965; Kulikova et al. 2009), Western Siberia (Stepanova 2007; Pozdeev 2010; Palatov & Chertoprud 2012), Eastern Siberia—Zabaikalye and Yakutia Region (Linevich 1981; Kravtsova 2000, 2010; our data), Kazakhstan (Minsarinova & Kiseleva 2007). All the above records are based on larval captures. Adults captures were recorded by Zelentsov (2013) and by Zelentsov & Shilova (1996) from Northern Karelia, by Shilova & Zelentsov (2000) from the North of Eastern Siberia. This species is widely distributed in Russian Far East: Primorye and Khabarovsk Territory, Magadan and Sakhalin Region, Kamchatka Peninsula (Makarchenko et al. 2005). It occurs also in China (Wang 2000) and Mongolia (Hayford 2005). The larvae live in the littoral zone of lakes, as well as in streams and rivers, building sand conical houses.