Selachops flavocinctus Wahlberg, 1844

(Figs 35–44)

Selachops flavocinctus Wahlberg, 1844: 68; Zetterstedt, 1848: 2792; 1860: 6463; Hendel, 1920: 115; 1936: 514; Frick, 1952: 386; Spencer, 1969: 12; 1976: 146; Zlobin, 1983: 49.

Encoelocera bicolor Loew, 1844: 321.

Material examined (deposited in ZISP). Estonia: 1 male, Tartu, “21/5 [18]83.”, “ Dorpat ”, “sec. typ. Loewii ”, “849”, “ bicolor Lw / flavocincta Whlb ”; 2 males, Tartu County, Kabina, 3.VI.1973 (Elberg). Finland: 1 female, Uusimaa, Nurmijärvi, 7.VI.1989 (M. Koponen). Moldova: 1 male, “ Purcary [= Purcari], Akkerman. u. Bessarab. Tchernavin 14 IV 911”. Russia: 2 females, Leningradskaya Province, Luga District, Yashchera, 13.VI.1957 (A. Stackelberg); 2 females, 1 male, same locality, 21.VI.1960, 13.VI.1964 and 26.VI.1966 (A. Stackelberg); 1 male, Leningradskaya Province, Tosno District, Ulianovka (= Sablino), 3.VI.1921 (V. Fridolin); 1 female, Sverdlovskaya Province, Yekaterinburg City, Verkh-Isetsk pond, Baran Island, 11.V.2008 (T. Kostromina); 1 female, 1 male, same locality, sweeping, 7.V.2013, (T. Kostromina); 1 male, Sverdlovskaya Province, Yekaterinburg City, Verkh-Isetsk pond, Baran Island, emerged 10.V.2015 ex puparium [7–1] collected 5.V.2015; 1 male, same locality, emerged 12.V.2015 ex puparium [9–5] collected 7.V.2015; 1 female, same locality, emerged 12.V.2015 ex puparium [11–2] collected 8.V.2015 (T. Kostromina, A. Timokhov); 2 females, 1 male, same locality, sweeping, 11.V.2008 and 7.V.2013 (T. Kostromina); 1 male, Primorskiy Territory, Khasan, 26.V.1979 (A. Zinoviev).

Distribution (Fig. 45). Austria, Czech Republic, Estonia, Finland, France, Germany, Hungary, Italy (Fauna Europea, 2016), Moldova (new record), Russia (Leningradskaya (Zlobin, 1983) and Sverdlovskaya Provinces, Primorskiy Territory (new records )), Sweden, Switzerland (Kahanpää, 2014, Fauna Europea, 2016), Ukraine (Korneyev, 2002).

Host plant. Carex acuta Linnaeus, 1753 (Poales: Cyperaceae).

Remarks. There is very little information on the immature stages of the genus Selachops. Dempewolf (2001) gave the description of the S. flavocinctus puparium in an unpublished PhD dissertation. Herein a redescription of the puparium providing additional characteristics and new data on life history of S. flavocinctus are published for the first time.

Description. Puparium (Fig. 37, 40–44). Length 5.4–6.1 mm, width 2.2–2.3 mm. Black, mat. Integument corrugated with conspicuous intersegmental constrictions. Cephalic end (segments I–III) (Figs 42, 43) dorsoventrally flattened, tapering gradually to anterior end (lateral view), with lateral flanges. Caudal end (Fig. 44) slightly broadened, almost evenly rounded, twelfth segment with small depression mediodorsally. Anterior and posterior spiracles rather similar, with numerous distinct papillae. Anterior spiracles retained as conspicuous projections at anterolateral margin of dorsal cephalic cap. Distance between anterior spiracles 2.4–2.8 × their diameters. Posterior spiracles slightly projected dorsolaterally, distance between posterior spiracles 1.2–1.5 × their diameters. Anal plate almost round; anal opening conspicuous, slit-shaped, surrounded with numerous minute spines.

Cephalopharyngeal skeleton (extracted from puparium). Length 0.65 mm. Paired mouthhooks (mandibular sclerites) notably separate from each other, stout, about 1.5 × as high as maximum length. Each mouthhook bifurcated anteriorly in its upper third into two teeth which are notably downturned, lower teeth slightly smaller, laterad to upper teeth. Mouthhooks joined ventrally by two sclerites forming V-like structure, and articulated posteriorly with front of hypostomal sclerite. Hypostomal sclerite elongate, 3.0 × longer than height, 1.9 × longer than its maximum width, distinctly narrowed medially (dorsal view). Pharyngeal sclerite appearing continuous with hypostomal sclerite, enlarged, with two dorsal and two ventral cornua. Dorsal cornu wide, elongate, almost twice as long as ventral cornu, its apical part sharply tapering, with elongate slit-like open fenestra. Ventral cornu distinctly widened, with closed fenestra.

Life history. Late instar larvae feed as stem miners in culms of Carex acuta. Most of the burrows produced in the culm lie below the level of the soil surface. The burrow always extends as far downward as the culm base. Pupation is within a culm (no puparia were found outside sedge culms) on height 1.5–4.0 cm above the culm base; pupa vertical, always orientating head up (Fig. 37). Flies overwinter in pupal stage. In the Central Urals, adults begin to emerge about middle of May.