Melanogaster jaroslavensis ( Stackelberg, 1922 )

Popov, Grigory V. & Prokhorov, Alexey V., 2020, Revision of the Melanogaster jaroslavensis group (Diptera: Syrphidae), with description of a new species from Afghanistan, Zootaxa 4743 (4), pp. 536-552 : 538-542

Melanogaster jaroslavensis ( Stackelberg, 1922)

Figs 1 A–F; 2A–C; 3; 4A–C; 5A

Chrysogaster jaroslavensis Stackelberg, 1922: 363 . Type locality: Russia [LT ♂ ZIN]

Chrysogaster jaroslavensis: Stackelberg (1923: 226 ; 1933: 230; 1953: 269; 1958: 194, 221; 1959: 898, 900), Sack (1928: 36), Peck (1988: 134), Richter & Kuztentsov (2007: 10), Pestov et al. (2010: 91)

Melanogaster jaroslavensis: Maibach et al. (1994 a: 230)

Melanogaster jaroslavensis: Maibach et al. (1994 b: 268) , Vujić & Stuke (1998: 346)

Material examined. Lectotype, ♂ [Beditsino (Berditsino), Yaroslav. u. (= uezd, = Region), near puddle, Lupinus flowers, 2.VI.1908, A. I. Yakovlev leg., Yakovlev coll.] ( ZIN) . Paralectotypes (all ZIN): 2♂♂, 2♀♀ [Berdits (ino), Barbarea flowers, 26, 28.V.1907, A. Zhuravsky leg.], ♀ [Berdits (ino), Barbarea flowers, 22.V.1907, A. Zhuravsky leg.], 3♀♀ [Berditsino, Yaroslav. u., 26.V.1907, A. Yakovlev leg.], ♀ [Berditsino, Yaroslav. u., 7.VI.1908, A. Ya- kovlev leg.] . Additional material (all SIZK): ♀ [ Ukraine, Sumy Reg., Matskove env., 51.48N 33.90E, Esman River valley , Ranunculus flowers, 10.V.2018, M. Zaika leg.], 2 ♂♂, ♀ [idem, 15.V.2018, M. Zaika leg.] .

Diagnosis. Body length: 6.4–7.1 mm. Melanogaster jaroslavensis male differs from males of the new species and M. tadzhikorum by: much narrower relative face and frons width; facial tubercle shape (distinctly protruded in M. jaroslavensis , weakly protruded or almost absent in those species); halter colour (entirely yellow in M. jaroslavensis ); surstylus shape (in lateral view the surstyli elongated and narrow in M. jaroslavensis , short and broad in those species). Hypopygium very similar to M. kirgisorum ; hypandrium and epandrium typical for M. hirtella species-group ( Maibach et al., 1994 a; Kassebeer, 1999 a). Melanogaster jaroslavensis male can be separated from M. kirgisorum male by: brightly shining frons and anepisternum without pollinosity; even narrower face and frons; shape of facial tubercle in lateral view (more acute in contrast to M. kirgisorum ); length of both anepisternum and anepimeron pile (both very short pilose in M. jaroslavensis but covered with distinctly long pile in M. kirgisorum ); genitalia structure (in ventral view parameres almost straight apically in M. jaroslavensis but hook-shaped in M. kirgisorum , in dorsal view surstyli emarginated laterally at the base but almost straight in M. kirgisorum ). Female of M. jaroslavensis can be distinguished from females of the new species and M. tadzhikorum by narrower frons, from M. kirgisorum female by: even narrower frons; body with short pile and sternites shiny.

Redescription. MALE ( Figs 1A, C, E ; 2 A–C; 4A–C). Body dark olive greenish, length 6.4–7.1 mm. Head ( Figs 1C, E ; 4A, B ). Eyes bare, holoptic, eye contiguity 0.5 times as long as the height of the ocellar triangle; frons slightly swollen, shiny black, upper half with long whitish pile; face and frons narrow, the ratio of the maximum width of the head to the width of the frons at the level of the antennal base 2.6–3.1, frons shiny, apart from pollinose stripe between eyes from antennal base to facial tubercle; facial tubercle distinctly protruded; upper mouth-edge strongly protruding forward (further than the median facial tubercle); lower part of the face with sparse pale pile; antenna black including bare arista; ocelli nearly equidistant, but the distance between the posterior ocelli slightly greater; vertex with mixed pale and dark pile, occiput pale pilose. Thorax ( Fig. 1A, C ). Scutum and scutellum shiny dark olive greenish, not pollinose, finely punctated, covered with short subadpressed yellowish pile; sides of thorax shiny; proepisternum, posterior anepisternum, anepimeron, katatergite, anterior part of proepimeronand upper part of katepisternum with sparse short whitish pile; anterior anepisternum, meron, metapleuron, posterior part of proepimeron and katepimeron bare. Legs brownish-blackwith light pile, long pile whitish, short pile yellowish on tarsi. Wing ( Fig. 1A, C ). Length: 4.9–5.2 mm. Hyaline, entirely microtrichose, clearly yellowish basally, as well as veins yellow near base but brownish apically; pterostigma yellow; vein M joining vein R 4+5 at right angle; calypter whitish with yellowish edge; halteres yellow. Abdomen ( Fig. 1 A ). Shiny, general colour dark olive greenish. Tergite I slightly rugose, tergites II–IV distinctly transversely rugose. Tergites I–III with distinct pollinosity dorsally, greenish-bronze on the sides, tergite IV shiny greenish-bronze except triangular matt black spot on two-thirds of the tergite length, tergite VIII shiny bronze black. Tergites covered with short adpressed pale pile except tergites I–II with long erect pile on sides. Sternites shiny, greenish-bronze with inconspicuous transverse rugosity, with adpressed pale pile except sternites I–II with more long erect pile. Genitalia ( Figs 2 A–C; 4C). Parameres almost straight apically in ventral view; surstyli elongated with widened base, slightly curved in lateral view, emarginated laterally at the base in dorsal view; cerci kidney-shaped in dorsal view.

FEMALE ( Figs 1B, D, F ; 5A ). Body length: 6.9–7.1 mm. Similar to the male except for sexual dimorphism, and differing by the following characters. Head ( Figs 1D, F ; 5A ). Frons narrow, ratio of the maximum head width to the frons width at the level of the antennal base 2.1–2.3, ratio of the maximum head width at the level of the antennal base to the vertex width 3.6–3.9. Frons and vertex shiny, occiput pollinose, with sparse short pale pile; frons with weak but clearly visible transverse furrows and roughly dotted; face pollinose in upper half, shiny in lower half, with sparse whitish pile. Thorax ( Fig. 1B, D ). Scutum and scutellum shiny greenish or blackish, covered with short whitish-yellowish pile. Wing ( Fig. 1B ). Length 5.6–5.7 mm. Abdomen ( Fig. 1B ). Sternites shiny, sternites III–IV with weak pollinosity at anterior edge, sternite V entirely weakly pollinose, not so shiny.

Distribution. From Central European Russia (Leningrad, Yaroslavl, Perm, Kirov Regions) ( Stackelberg, 1922, 1923, 1953, 1958, 1959; Peck, 1988; Pestov et al., 2010) into northern Ukraine (new record).

Biology. The preferred environments are alluvial forests and wet meadows in the vicinity of rivers. In the Sumy Region ( Ukraine) all specimens were collected on a floodplain near the edge of an Alnus glutinosa forest ( Fig. 3 ). The flowers visited are: Ranunculus , Caltha , Barbarea ( Stackelberg, 1922, 1953, 1958, 1959; this study).Adults fly in May in the southern parts of the range, and June in the northern parts (10.V–20.VI). The larva is unknown.

Figures

FIGURE 1. Melanogaster jaroslavensis. A: Male, dorsal view; B: Female, dorsal view; C: Male, head and thorax, lateral view; D: Female head, lateral view; E: Male head, frontal view; F: Female head, frontal view. Scale line = 1 mm.

FIGURE 2. Melanogaster jaroslavensis, male genitalia. A: Epandrium, ventral view; B: Hypopygium, lateral view; C: Hypandrium, ventral view). Scale line = 0.1 mm.

FIGURE 3. Melanogaster jaroslavensis habitat (Sumy Reg., Ukraine).

FIGURE 4. Male paralectotypes of Melanogaster jaroslavensis (A–C), M. kirgisorum (D–F) and M. tadzhikorum (G–I). A, D, G: Head, frontal view; B, E, H: Head, lateral view; C, F, I: Hypopygium, ventral view.

FIGURE 5. Female paralectotypes of Melanogaster jaroslavensis (A), M. kirgisorum (B) and M. tadzhikorum (C), head, dorsal view.