Rhamphomyia (Holoclera) vikhrevi, Shamshev & Barták, 2024

Shamshev, Igor V. & Barták, Miroslav, 2024, New species and records of the Rhamphomyia subgenus Holoclera (Diptera, Empididae) from the Palaearctic Region, Zootaxa 5512 (4), pp. 512-530 : 524-526

Rhamphomyia (Holoclera) vikhrevi sp. nov.

( Fig. 4 )

Type material. HOLOTYPE ♂, labelled: MOROCCO, Oukaimeden 2000 m, 31.227N, 7.812W, N. Vikhrev 17.v.2012 ( ZMMU) . PARATYPES. MOROCCO. Aguelmouss 2050 m, 31.260N, 7.411W, N. Vikhrev 12.v.2012 (1 ♂, CULSP) , same data as holotype (1 ♀ CULSP; 1 ♂, 2 ♀ ZMMU; 1 ♂ ZISP); Imlil [31.135°N, 7.919°W], High Atlas, 1740 m, 8.v.1993, G. Shewell (1 ♂ CNC) .

Diagnosis. Black species of the R. (H.) nigripennis group with black palpus, uniserial dorsocentrals, fore coxa paler than pleura, supra-alar seta absent, cercus almost straight dorsally (not deeply concave), short phallus, and hypandrium with two strong and long setae.

Description. Male ( Fig. 4A ). Body 4.0– 4.1 mm, wing 4.4–4.8 mm. Head brown, entirely pruinose, black setose, eyes holoptic. Frons confined to small triangle above antennae, without setulae. Dorsal half of eye with greatly enlarged ommatidia. Ocellar triangle prominent, pruinose; ocellar setae fine and approx. 0.20 mm long. Occiput sparsely covered with black setae as long as ocellars or shorter, postocular row incomplete. Face nearly 0.15 mm wide, bare. Clypeus pruinose, gena very narrow. Antenna black, both basal segments short setose; postpedicel nearly 3X longer than basal width; stylus nearly 1.5X shorter than postpedicel. Labrum black, shiny, slightly longer than head height; labellum narrow with rather long setae. Palpus black, short, with several very short setae.

Thorax brown in ground-colour. Mesoscutum faintly pruinose; in anterodorsal view brownish grey and with two narrow dark vittae between dorsocentrals and virtual acrostichals; in dorsal view uniformly brownish. All thoracic setae black. Antepronotum with several short setae on each side. Proepisternum with several short and fine setulae. Prosternum and upper part of proepisternum bare; postpronotal lobe with 1 long, strong and several much shorter setulae. Mesonotal chaetotaxy: acrostichals absent; dorsocentrals uniserial, 3–4 anterior pairs approx. 0.20 mm long and oriented posteriorly as usually, posterior 2–3 pairs oriented anteriorly; 1 long presutural supra-alar; notopleuron with 3 long setae and 1–2 smaller setae in anterior part; postsutural supra-alar (including prealar) region without setae; 1 long and 1 short postalar; 2 pairs of scutellars. Laterotergite black setose.

Legs colour: fore coxa and trochanter yellow to light brownish yellow, much lighter than pleura; mid and hind coxae and trochanters brown; femora and tibiae yellowish brown, hind tibia at apex and tarsi brown. All legs sparsely pruinose, black setose. Fore femur with anterior row of spine-like setae (approx. 0.03 mm long). All femora and fore tibiae without prominent setae except preapicals. Mid tibia with 0–1 scarcely distinguishable setae both dorsally and ventrally. Hind tibia with several setae ventrally shorter than tibia depth and with several setae dorsally somewhat longer than tibia depth. Tarsi of all legs slender and long; short setose. Seta in comb at tip of hind tibia very short, not longer than setae forming comb.

Wing brownish tinged, veins brown, axillary angle right to slightly obtuse; costal seta short. Measurements: M2/d ratio = 1.3–1.9, CuA1 ratio = 3.9–4.7, lw:ww ratio = 2.6–2.8. Halter brow, calypter brown with dark fringes.

Abdomen brown, subshiny, black setose. Lateral marginal setae on tergites 2–3 as long as corresponding segments, remaining tergites with somewhat shorter setae; sternites with long setae, those on segments 3–7 with long pair of median setae.

Hypopygium as in Fig. 4B, C . Hypandrium with two long and strong setae; epandrium elongate and without apical spines; cercus slightly concave dorsally, phallus rather short.

Female. Body 4.5 mm, wing 4.9 mm. Dichoptic, all ommatidia almost equal in size, frons pruinose, approx. 0.10 mm broad with 3–4 black setae subequally long as frons width. Otherwise very similar to male, only hind femur with prominent subapical anteroventral seta.

Etymology. The species epithet, vikhrevi , is a Latin genitive patronym to honour of Russian dipterist Nikita Vikhrev (Moscow), who kindly provided his very interesting specimens used in this study.

Remarks. Rhamphomyia (H.) vikhrevi sp. nov. is similar to R. (H.) helvetica Barták & Kubík. However , the new species differs from the latter species in the shape of genitalia (compare fig. 3 in Barták & Kubík (2012) with Fig. 4C ). In R. (H.) helvetica , the hypandrium is differently setose and the phallus is much narrower than in R. (H.) vikhrevi sp. nov. In addition, the shape of the cercus in the new species is different, being slightly concave dorsally rather than straight in R. (H.) helvetica . Similarly as in R. (H.) nigripennis , the male cerci of the new species have a distinct basal swelling (absent in R. (H.) helvetica ). Also, the female is similar to R. (H.) helvetica , however, it has a subapical anteroventral seta on the hind femur similar to R. (H.) tenuipes. Moreover, the above described species is markedly larger than the remaining species of the R. (H.) nigripennis group (wing length of all other species of this group is less than 4 mm).

Prior to our study, only one species of R. ( Holoclera ) was reported from Morocco, namely R. (H.) tenuipes Becker ( Kettani et al. 2022). Currently, the subgenus includes two species from Morocco.

Distribution. Morocco, High Atlas Mountains.

Figures

FIGURE 4. Rhamphomyia (Holoclera) vikhrevi sp. nov., male. A. Habitus, lateral view. B, C. postabdomen, lateral view. Abbreviations: cerc—cercus; epand—epandrium; hypd—hypandrium; ph—phallus. Scale bars: A—1 mm, C—0.1 mm.