Drapetis yangambensis, Grootaert & Shamshev, 2014

Grootaert, Patrick & Shamshev, Igor, 2014, New Tachydromiinae (Diptera: Empidoidea: Hybotidae) from different types of forests along the Congo river (D. R. of the Congo), Belgian Journal of Entomology 18, pp. 1-34 : 1-34

Drapetis yangambensis sp. nov.

( Figs 7–11 )

ETYMOLOGY. The specific epithet refers to the type locality Yangambi.

TYPE MATERIAL. Holotype, ♂: D. R. CONGO, Yangambi , 7 June 2012 (reg. 32004, leg. P. Grootaert, MS reference Drap 6) ( RBINS). Mid leg in tray Congo 2 at C1 was extracted for DNA and a COI barcode is available at GenBank.

Paratypes: 1♀ same provenance as holotype; 1♂, Yangambi, 13 June 2012 (reg. 32036, leg. P. Grootaert) ( RBINS) .

DIAGNOSIS. Small species with brown antenna and palpus; legs almost entirely yellow only tarsomere 5 of all legs brownish; halter yellow.

DESCRIPTION.

Male. Occiput black, pollinose, viewed laterally rather subshining; with longer setae brownish; inner verticals long, inclinate. Anterior ocellars short, inclinate and cruciate; posterior ocellars slightly shorter, lateroclinate. Frons narrow, above antennae narrower than anterior ocellus, widened toward ocellar tubercle, subshining. Antenna brown; postpedicel conical, with lower margin convex; nearly 2.0 times as long as wide; stylus apical, darker basally and paler apically, long, nearly 3.0–3.5 times as long as postpedicel. Proboscis brown. Palpus brown, small, rounded, bearing scattered setulae, subapical seta short, thin.

Thorax black, shining, larger bristles yellow to brownish yellow. Prothoracic episterna without long upturned seta just above fore coxa, with several setulae on upper part. Postpronotal seta not prominent. Anepisternum (= mesopleuron) with numerous setulae on upper posterior corner. Mesonotum with 2 notopleurals, 1 postsutural supra­alar, 1 postalar and 4 scutellars (apical pair very long, cruciate; lateral pair minute); acrostichals and dorsocentrals undifferentiated, scutum evenly covered with numerous setulae, 1 pair of prescutellars long.

Legs robust, almost entirely yellow, only tarsomere 5 of all legs brownish (more distinctly on fore and mid legs). Coxae and trochanters with unmodified setation. Fore femur with rows of minute anteroventral and posteroventral setulae, 1 long thin seta near base. Fore tibia lacking prominent setae (except subapicals). Mid femur with rows of anteroventral and posteroventral setulae (the latter dark and spinule­like on about basal half), 1 short subapical seta anteriorly. Mid tibia with double row of dark, ventral, spinule­like setulae, lacking long setae (except subapicals). Hind femur with 2 moderately long anteroventrals subapically and some short erect dorsal setae near base. Hind tibia lacking prominent setae; apical projection small, rounded. Tarsi of all legs unmodified, with unmodified setation.

Wing normally developed, almost uniformly finely infuscate (slightly darker on central part), paler near base, veins brownish on darkened part, otherwise pale yellow. Costal bristle moderately long, brownish. Costal index: 34/20/20. Vein R 2+3 rather evenly curved. Veins R 4+5 and M 1+2 divergent near wing apex, both slightly bowed. Crossvein bm­cu perpendicular. Crossvein r­m before middle of cell bm. Halter yellow.

Abdomen. Tergite 1 pale, otherwise tergites brown; tergites 2–3 of subequal width (viewed laterally), with ordinary setae; tergite 4 broadest, with squamiform setae laterally; tergite 5 very narrow dorsally, with ordinary setae; tergites 6–7 of subequal width, with ordinary setae, tergite 7 with moderately long posteromarginal setae laterally. Sternites well sclerotised, sternites 4–5 divided medially, sternite 3 broadly convex posteriorly, bearing scattered setulae. Gland­like structure present between tergites 4–5. Terminalia ( Figs 7–11 ) moderately large, brown. Cerci separated; right cercus short, digitiform, with ordinary setae; left cercus longer than right cercus, digitiform, with ordinary setae. Epandrium completely divided. Right epandrial lamella covered with numerous ordinary setae; right surstylus divided into 2 sclerites; dorsal sclerite rather falciform, broadened on middle part, narrowed and pointed apically (dorsal view), with some short ordinary setae; ventral sclerite digitiform, pointed on apex (dorsal view), with several short ordinary setae. Left epandrial lamella fused to hypandrium, with several short setae apically; left surstylus large, subglobular, with ordinary setae. Phallus short. Two rod­shaped apodemes.

Length (mm). Body 2.1, wing 1.7.

Female. Mid tibia without dark ventral spinule­like setulae; tergites 3–5 with squamiform setae laterally; tergite 7 with subglobular excisions leaving furcate median part posteriorly; sternites 4–5 undivided; segment 8 rather narrow; cercus small, rounded, brownish. Otherwise as in male.

COMPARISON. The new species is similar to D. zamba Grootaert & Shamshev, 2013 described from D. R. Congo ( GROOTAERT & SHAMSHEV, 2013). However, D. yangambensis sp. nov. has a yellow halter (cf. brown in D. zamba ) and brownish tarsomere 5 of all legs (cf. yellow in D. zamba ).

DISTRIBUTION. D. R. Congo.

Figures

Figs 7–11. Drapetis yangambensis sp. nov., 7. Right epandrial lamella, lateral view; 8. Ventral sclerite of right surstylus, dorsal view; 9. Dorsal sclerite of right surstylus, dorsal view. 10. Terminalia, dorsal view; 11. Left surstylus, lateral view.