Sybistroma occidasiatica, Grichanov, Igor Ya. & Kazerani, Farzaneh, 2014

Grichanov, Igor Ya. & Kazerani, Farzaneh, 2014, A new species of Sybistroma Meigen (Diptera: Dolichopodidae) from the Middle East with a key to West-Palaearctic species of the genus, Zootaxa 3866 (4), pp. 572-582 : 575-577

Sybistroma occidasiatica sp. nov.

( Figs 1–7 )

Type material. HOLOTYPE ♂ “ Turkey: [Antalya reg.,] near Manavgat, uncultivated plot, 26.II.2008, N. Vikhrev” [ MZUM]. PARATYPES (pinned): 1♂, same data as holotype [ ZIN]. Iran. 1♂ (in 75% ethanol in glass vial), East Azerbaijan province, Shabestar region, 38°41.05' N; 45°31.85' E, 1790 m a.s.l., 29.VII.2013, Roia Namaki [ IMTU]. Israel. 1♂, Kadoorie, 6.III.1985, A. Freidberg [ TAU]; 2♂, Nafech [H. Nappah], 15, 18.III.1985, M. Kaplan [ TAU]; 2♂, Jagur, 21.II.1976, A. Freidberg [ TAU]; 2♂, 1♀, [Golan Heights] Qusbiya, 31.I.1978, D. Furth [ TAU]. Turkey. 2♂, 3♀, Antalya reg., near Manavgat, sweeping on ruderal Cruciferae, 26.II.2008, K. Tomkovich leg. [ MZUM].

Diagnosis. Antenna entirely black, stylus longer than postpedicel; postocular setae black; legs black except brownish knees; all tarsi simple. This species seems related to S. inornata (for differences, see the identification key above). It superficially resembles some species of the genus Hercostomus , e.g. H. fugax Loew and H. vivax Loew ( Grichanov 2007; Negrobov & Nechay 2009), differing in the reduced antennal pedicel, enlarged postpedicel, tripartite arrangement of basiventral epandrial lobes and hypandrium in ventral view, enlarged setulose apicoventral epandrial lobe of hypopygium and many fine morphological characters.

Etymology. The species name originates from Latin “Asia occidentalis” (West Asia).

Description. Male ( Fig. 1 ): Head: antenna entirely black; scape with dorsal setae and about 2 times as long as pedicel; pedicel reduced (from outer view), slightly protruded into postpedicel (from inner view), postpedicel, slightly variable in shape, about 2 times as long as high, with distinct apicodorsal apex and more or less distinct apicoventral apex; stylus shortly haired, about 1.5 times longer than postpedicel, located at about 3/4 of its dorsal surface; 1st and 2nd articles of stylus variable in length: 2nd article nearly 2 times longer than 1st article (holotype and part of paratypes: phenotype A, Fig. 3 ) or 2nd article only slightly longer than 1st article (phenotype B, Fig. 4 ); frons black, grey pollinose; eyes finely haired; face black, weakly grey-brown pollinose; ratio of height to width under antennae to width at clypeus, 0.38/0.29/0.17; clypeus black; proboscis dark brown; all postocular setae black. Thorax: all setae black; pronotum pubescent, with black hairs; mesonotum grey pollinose; 6 dorsocentral setae, 7 acrostichals, short, biserial; pleura dark, with weak grey pruinosity; scutellum with 2 strong setae, 2 fine lateral setae. Legs: entirely black with brownish knees, hairs and setae black; all tarsi simple; fore leg with coxa bearing numerous black hairs laterally and 2 strong setae apically, femur without subapical posterior seta, tibia with 2 anterodorsal, 3 posterodorsal setae, no long apicoventral seta; midleg with coxa bearing some black hairs laterally and 1 strong setaeapically, femur with 1 anterior subapical seta, tibia with 3 posterodorsal, 2 posteroventral and 6 apical setae; hindleg with coxa bearing 1 strong seta, femur with 1 anterior subapical seta and some posterodorsal cilia, tibia with 7 posterodorsal and 4 ventral setae. Femur, tibia and tarsomere (from first to fifth) length ratio: fore leg: 1.02/0.98/0.50/0.26/0.20/0.12/0.15, mid leg: 1.22/1.41/0.67/0.39/0.28/0.18/0.20, hind leg: 1.36/1.62/0.49/0.60/ 0.38/0.24/0.23. Wing ( Fig. 2 ): membrane greyish, brownish anteriorly, veins brown; R1 thickened; costa thickened, with short brown setae dorsally; R2+3 almost straight, R4+5 curved towards M1+ 2 in apical fourth, M and R4+5 slightly convergent distally, becoming parallel at apex; M joining costa right before wing apex; ratio of costal section between R2+3 and R4+5 to that between R4+5 and M1+2: 0.45/0.13, distal part of CuA1 about 2 times longer than dm-cu; anal vein distinct; lower calypter dark brown, light basally, with black cilia; halter dark brown to black. Abdomen: greenish-black and shiny, with black hairs and marginal setae; 8th segment dark brown, with black cilia. Male genitalia ( Fig. 5 ): epandrium black, elongate-oval, as long as tergites 5–6 combined; hypandrium flanked laterally by basiventral epandrial lobes forming tripartite arrangement in ventral view; basiventral epandrial lobes symmetrical, each lobe spear-shaped with pointed setose apical knob; apicoventral epandrial lobe well-developed, prominent, thin in ventral view, with more or less distinct apical extension, setulose apically; aedeagus thin and long, with large dorsal furcate projection; surstylus dark brown, bilobed, ventral lobe digitiform and slightly curved, with dorsal hump, with short apical setae and 2 strong spines, dorsal lobe thin, expanded at middle, curved ventrally, with short apical setae and 1 strong spine at middle; cercus dark brown; elongate-ovate with preapical dorsal projection, with light and dark simple setae basally and strong black setae along margin distally. Measurements: Body length 3.3–3.5 mm, antenna length 1.0- 1.1 mm, wing length 3.6 mm, wing width 1.3 mm, hypopygium length 1.0 mm. Female: Similar to male except lacking male secondary sexual characters, otherwise as follows. Body length 4.1 mm, antenna length 1.0 mm, wing length 3.8 mm. Face black, weakly grey pollinose, nearly parallel-sided; ratio of its height to width at clypeus, 0.51/0.27; postpedicel slightly variable in shape, about 1.5 times as long as high; stylus about 2 times longer than postpedicel; 2nd article of stylus 2.1 (phenotype A, fig. 6) or 1.5 (phenotype B, fig. 7) times longer than 1st article.

Figures

FIGURE 1. Habitus of Sybistroma occidasiatica sp. nov., male.

FIGURE 2. Wing of Sybistroma occidasiatica sp. nov., male.

FIGURE 3. Antenna of Sybistroma occidasiatica sp. nov., male, phenotype A (Turkey)

FIGURE 4. Antenna of Sybistroma occidasiatica sp. nov., male, phenotype B (Israel).

FIGURE 5. Hypopygium of Sybistroma occidasiatica sp. nov., left lateral view (ventral setae of cercus not shown). Abbreviations: aepl—apicoventral epandrial lobe, bepl—basiventral epandrial lobe, cer—cercus, ep—epandrium, hyp—hypandrium, pgt—postgonite, ph—phallus, dsur, vsur—surstylus (dorsal and ventral lobes).

FIGURE 6. Head of Sybistroma occidasiatica sp. nov., female, phenotype A (Israel)

FIGURE 7. Antenna of Sybistroma occidasiatica sp. nov., female, phenotype B (Israel).