Myiocephalus niger Fischer, 1957

Figs 17–35

Myiocephalus niger Fischer, 1957: 14–16; Shenefelt 1969: 116; Belokobylskij 2000: 372; Lozan et al. 2011: 6 [examined]. Loxocephalus niger; Tobias, 1986: 247 (transl. p. 432); Bergamesco et al. 1995: 17.

Material. 3 ♀ + 1 ♂ (NWUX, RMNH), “ NW China: Shaanxi, Liangfengya, Foping, N33.09° E107.90°, 20.vii.– 26.xi.2017, 1729 m, Y[ellow] Mal. trap, Tan JL & Tan QQ, NWUX” ; 1 ♀ (RMNH), “ I [taly], Abruzzo, AO, Campo di Giove, Tavola Rotanda, 1400 m, 20.vi. [1]988, P.L. Scaramozinno ” ; 1 ♀ (RMNH), “ Netherlands: Gld., Nunspeet, Mal. trap, 19.vii.2003, B. v. Aartsen, RMNH’04” ; 1 ♂ (RMNH), “ Bulgaria, Rila Mts ”, “k. Maloviza, 23.vii.1982, A. Zaykov”; 1 1 ♂ (RMNH), “BG: Rhodopi, Selishte, 26.vi.1978, A. Zaykov ” .

Short diagnosis. Length of malar space of ♀ about equal to basal width of mandible (Fig. 28; of ♂ approx. 1.2 ×); occipital carina dorsally distinctly below upper level of eye and straight laterally (Fig. 28); basal half of first metasomal tergite straight laterally and nearly parallel-sided in dorsal view, without laterope visible (Fig. 24); hypopygium of ♀ largely membranous ventrally, unsclerotized, protruding latero-posteriorly and comparatively short bristly setae (Fig. 25); only apical third of exserted ovipositor slender in lateral view (Figs 17, 20); mesosoma laterally and legs mainly dark brown (Figs 17, 31).

Redescription. Specimen from China (Shaanxi), ♀, length of fore wing 3.8 mm, and of body 5.5 mm.

Head. Antenna with 28 segments and 1.2 × as long as fore wing, length of third segment 1.2 × fourth segment, third, fourth and penultimate segments 5.5, 4.5 and 2.1 × as long as wide, respectively (Figs 29, 30); length of max- illary palp equal to height of head, segments slender (Fig. 28); eye 4.1 × as long as temple in dorsal view; temples directly and linearly narrowed behind eyes (Fig. 27); OOL:diameter of posterior ocellus:POL = 10:3:10; vertex and frons largely smooth and shiny, in front of ocelli and vertex medio-posteriorly partly coriaceous; in front of anterior ocellus with depression (Figs 26, 27); occipital carina complete and dorsally remaining far below upper level of eyes (Fig. 28); combined length of clypeus and face (measured from ventral rim of antennal socket to ventral border of clypeus) 1.1 × minimum width of face; face mainly very finely coriaceous, with some rugulae and pale yellowish setae, and with satin sheen (Fig. 26); clypeus convex, medio-ventrally lobe-shaped protruding over slightly concave and thin ventral rim (Figs 26, 28), medially remotely and finely punctate and laterally with some rugulae; anterior tentorial pits large (Fig. 26); malar suture deep, narrow and straight; length of malar space 0.9 × basal width of man- dible, malar space concave in anterior view (Fig. 26); mandible slender, strongly twisted (Figs 26, 28), outer side convex and with deep basal depression (Fig. 28), its second tooth medium-sized and acute (Fig. 26).

Mesosoma . Length of mesosoma 1.4 × its height; side of pronotum largely smooth, but oblique groove crenulate anteriorly, ventrally with some rugulae and posteriorly with some crenulae (Fig. 23); mesopleuron antero-dorsally densely striate and partly costate (Fig. 23), posteriorly partly superficially striate, remainder shiny and largely smooth; prepectal carina absent postero-laterally; precoxal sulcus absent except for shallow depression posteriorly; episternal scrobe linear, long and posteriorly deep (Fig. 23); mesosternum sparsely setose, convex and shiny; mesosternal suture shallow, narrow and smooth; notauli absent except for indistinct impression and mainly smooth anteriorly (Figs 22, 23), mesoscutum very sparsely setose, flattened, moderately shiny and its posterior half aciculate (Fig. 22); scutellar sulcus smooth and deep (Fig. 22); scutellum convex, smooth (except some aciculae antero-laterally) and shiny, medio-posteriorly convex, smooth and no depression; metapleuron coriaceous-rugulose (Fig. 23); propodeum triangularly depressed medially, anteriorly smooth and shiny, remainder rugulose or finely rugose, and anterior face hardly separated from posterior face (Fig. 22).

Wings. Fore wing: 2-M unsclerotized; 1-R1 1.1 × longer than pterostigma; marginal cell slender Fig. 21); r:3- SR+SR1:2-SR = 5:67:15; vein r issued submedially from pterostigma; vein SR1 slightly curved basally (Fig. 21); 1-CU1 hardly widened and oblique; cu-a vertical; 1-CU1:2-CU1 = 3:11; basal and subbasal cells of fore wing similarly setose as other cells. Hind wing: M+CU:1-M:1r-m = 40:3:10; basal half of M+CU unsclerotized.

Legs. Middle and hind legs very slender (tibia and tarsus about 2.5 × longer than femur, tibia approx. 4 × longer than coxa; Figs 17, 20); fore leg normal, tibia nearly 3 × as long as coxa; length of femur, tibia and basitarsus of hind leg 7.0, 18.8 and 15.6 × as long as their maximum width; hind tibial spurs 0.2 × as long as basitarsus.

Metasoma. First tergite 3.6 × longer than its maximum width, basal half subpetiolate, laterope invisible, slightly widened basally, flat (except minute depression near adductor) and smooth; posterior half convex, subparallelsided but gradually narrowed posteriorly (Fig. 24); first tergite open ventrally (Fig. 18) and laterope deep and large; following segments smooth, compressed and shiny, third–eighth tergites concave medio-apically (Figs 17, 20); sternites folded medially (Fig. 19), fifth sternite aciculate, medio-posteriorly with long setae and strongly protruding (Figs 19, 20, 25) and hypopygium membranous medially, protruding posteriorly and with apical fringe of comparatively short bristly setae (Fig. 25); second metasomal suture obsolescent; ovipositor sheath rather robust, parallel-sided and narrowed apically, setose part 0.15 × as long as fore wing (but dorso-basally glabrous); ovipositor compressed, widened in lateral view, except its slender apical third (Figs 20, 25).

Colour. Black; palpi, mandible, pedicellus, ventrally scapus, fore tibia and fore basitarsus mainly pale yellowish; face, tegulae, remainder of legs and of antenna, pterostigma, most veins of fore wing, and metasoma (except first tergite and ovipositor sheath) mainly brown to dark brown (Fig. 17); wing membrane weakly infuscated.

Variation. Length of fore wing 3.8–4.0 mm, and of body 5.5–5.8 mm; antenna with 28(1) or 29(1) segments; first tergite 3.6–3.9 × as long as its maximum width.

Male. Length of fore wing 3.3 mm, and of body 4.5 mm; antenna with 28 segments; length of malar space 1.2 × basal width of mandible; only sternites of basal half of metasoma folded medially and third–eighth tergites weakly concave posteriorly.

Biology. Unknown.

Distribution. West Palaearctic (Austria, Belarus, * Bulgaria, Czech Republic, Italy, Netherlands, NW Russia), and East Palaearctic (* China (Shaanxi), Far East Russia) regions. Collected near forested peatbog at less than 100 m above sea level (Netherlands) up to 1730 m (China; montane forest).

Notes. The specimens from China have the first metasomal tergite slenderer (3.6–3.9 × as long as its maximum width; 3.0–3.5 × in European M. niger) and are partly darker (tegulae, middle and hind femora (largely), tibiae (except narrowly basally and apically) and tarsi (except darkened telotarsus) dark brown; brown or brownish yellow in European M. niger), but the differences are relatively minor and considered to be intraspecific.