Hybos striatellus Villeneuve

Shamshev, Igor, Grootaert, Patrick & Kustov, Semen, 2015, New data on the genus Hybos Meigen (Diptera: Hybotidae) from the Palaearctic Region, Zootaxa 3936 (4), pp. 451-484 : 473-475

Hybos striatellus Villeneuve

( Figs 40–43 , 47 , 57 )

Hybos striatellus Villeneuve, 1913: 111 . Type locality: Oued Zous [ Algeria] (after lectotype designation).

Type material examined: LECTOTYPE (here designated in order to fix identity of the species), ♂ labelled: [ ALGERIA] “Oued Zous / 13 oct. [19]08 [hand-written]; Hybos / striatellus Villen. [hand-written] / det. D r Villeneuve; LECTOTYPE [red-label]” ( RBINS).

Additional material examined. ALGERIA: 1 ♂, 1 ♀, Algéria - El Kala, 29.ix.1993, leg. PG, coll. RBINS.

Recognition. Postpedicel without dorsal setae; scutum entirely brownish grey pollinose; mesonotum with black setae; legs with coxae and trochanters black, otherwise yellow to brownish yellow, with pale to yellow setae, mid tibia with 3–4 long, black anterodorsal bristles, hind basitarsus with black ventral spinules; abdomen with tergites greyish pollinose anteriorly and shining posteriorly, covered with pale yellow setae. Male: terminalia very large, globose; hypandrium narrowed towards apex, with narrow digitiform apical projection on right margin and small subapical excision on left margin.

Re-description. Male. Wing length 4.1 mm. Head black. Occiput densely greyish pollinose; with short black setae on upper part (becoming longer about middle) and yellowish to pale moderately long hair-like setae on lower part. Ocellar tubercle with 2 moderately long fine anterior ocellars and 2 minute posterior ocellars. Antenna black; postpedicel lacking setae. Proboscis dark brown. Palpus black, as long as labrum; with scattered short black setae.

Thorax black in ground-colour; entirely greyish to brownish grey (on scutum) pollinose. Proepisternum with 1 long black fine upturned seta. Antepronotum with several fine setae, black dorsally and yellow laterally. Postpronotal lobe with several short, fine black setae. Mesonotum mainly with black setation; 2 notopleurals (posterior seta longer), 1 postalar and 2 scutellars (with several short pale hair-like setae); supra-alar space with short fine black setae; dorsocentrals uniserial, black, fine and short, 1 pair of prescutellars long; acrostichals arranged in 4–6 irregular rows, as long as dorsocentrals, lacking on prescutellar depression.

Legs with coxae and trochanters black brown, fore and mid tarsomeres 3–5 and hind tarsomere 5 brown, otherwise yellow to brownish-yellow; covered with pale to yellow setae; coxae largely greyish pollinose, otherwise legs shining. Fore femur somewhat thickened, with rows of short fine brownish anteroventral and posteroventral setae. Fore tibia thickened; with 1 moderately long, black dorsal bristle just beyond middle, covered with numerous long, brownish-yellow hair-like setae posteriorly and ventrally; subapical circlet formed by several black setae of different lengths including 1 longest anterodorsal. Fore tarsomeres 1–2 clothed in numerous long outstanding brownish-yellow to yellow hair-like setae. Mid femur slender, with rows of short, fine brownish anteroventral and posteroventral setae and row of stronger (especially closer to apex) anterodorsal bristles. Mid tibia with 3–4 long, black dorsal and 2 thinner anteroventral bristles; subapical circlet formed by several black setae of different lengths including 1 longest anteroventral; otherwise mid tibia covered with rather short hair-like setae. Mid tarsus with similar but somewhat shorter setation to fore tarsus. Hind femur moderately thickened; with 1 complete and 1 incomplete (absent on about apical half) rows of short ventral spines, complete row of longer but sparser anterodorsal black spines, 5–6 moderately long, black strong anterodorsal bristles and several long, yellow closely set posteroventral bristles closer to apex; otherwise clothed in quite long (especially posteriorly) outstanding hairlike setae. Hind tibia thickened; lacking strong bristles; with short, hair-like, outstanding brownish-yellow setae. Hind tarsus clothed in short setulae; tarsomere 1 with several black, short ventral spinules.

Wing almost hyaline, finely infuscate; veins brownish; no costal bristle; stigma distinct, brownish, elongateovate; R1 close to costa subapically; R4+5 and M1+2 parallel closer to wing margin. Squama yellow, with pale setae. Halter yellow.

Abdomen black in ground-colour, tergites greyish pollinose anteriorly and shining posteriorly, covered with pale yellow setae longer laterally and on pregenital segments. Terminalia ( Figs 40–43 ) very large, globose, largely brown, surstyli black, subshining, bearing yellow setae. Right epandrial lamella subglobular (lateral view), with numerous moderately long to long setae; left surstylus saddle-shaped (lateral view), with digitiform ventral projection bearing several moderately long marginal setae and broadly rounded apical dorsal projection bearing several minute setae, with 6 long bristles on basal part. Left epandrial lamella narrow on basal part, broadened towards apex, truncate apically, with narrow apical notch closer to dorsal margin, bearing several long marginal bristles on apical part. Hypandrium narrowed towards apex, somewhat broadened subapically, with narrow digitiform apical projection on right margin and small subapical excision on left margin; bearing numerous, mostly very long bristles before broadened subapical part.

Female. Very similar to male. Fore tibia and fore basitarsus with shorter outstanding hair-like setae. Hind femur lacking incomplete row of ventral spines. Abdominal tergites 7–8 (except small shining path on tergite 7 posteriorly) and sternite 7 entirely pollinose, sternite 8 entirely shining; tergite 7 slightly narrowly concave anteriorly, nearly as large as tergite 6, somewhat produced laterally; sternite 7 considerably broader than sternite 6, stronger sclerotised, with several very long posteromarginal bristles; tergite 8 represented by two separated sclerites; dorsal sclerite with deep subtriangular cleft posteriorly, bearing 4–5 long, strong posteromarginal bristles laterally and 2 short posteromarginal bristles medially; ventral sclerite with median notch and slight median cleft anteriorly and posteriorly, bare; sternite 8 greatly reduced, represented by small narrow subrectangular laying vertically sclerite bearing 2 moderately long closely set bristles anteriorly and posteriorly; tergite 10 membranous, sternite 10 entire; cerci inside cavity formed by segment 8; cercus short, subglobular, brownish ( Fig. 57 ).

Remarks. Villeneuve (1913) described H. striatellus after 2 males and 1 female collected by M. Lesne (MNHN) from Algeria. One male and 1 female are housed in Paris (MNHN) and 1 male is deposited in Brussels (RBINS). The lectotype is in very good condition. In the Palaearctic Catalogue Chvála & Kovalev (1989: 187) placed H. striatellus among doubtful species of Hybos and mistakenly indicated the type locality as “ France ” which was followed by Yang et al. (2007). Villeneuve (1913: 111) notes that M. Lesne collected H. striatellus from “Oued Zous”, Algeria, though a province of France at that time. Hybos striatellus can be readily distinguished from other species of the genus known from Europe and the Mediterranean by features that have been noted in the key.

Distribution. PALAEARCTIC: Algeria ( Fig. 47 ).

Figures

FIGURE 47. Distribution map of Hybos andradei sp. nov., H. striatellus and H. vagans.

FIGURES 40 – 43. Hybos striatellus, male terminalia. 40. tip hypandrium, dorsal view; 41. hypandrium, ventral view; 42. right epandrial lamella, lateral view; 43. left epandrial lamella, lateral view. Scale bar— 0.1 mm.

FIGURES 55 – 59. Hybos, female terminalia. 55, 56. H. mediasiaticus sp. nov.: 55. ventral view, 56. lateral view; 57. H. striatellus, ventral view; 58, 59. H. vagans: 58. ventral view, 59. lateral view. Abbreviations: c—cercus, fr—furca, T 8, T 10 — tergites 8 and 10, S 8, S 10 — sternites 8 and 10, respectively. Scale bar: 0.1 mm.