Elaphropeza excavata Grootaert et Shamshev

Grootaert, Patrick & Shamshev, Igor, 2013, The flies of the family Hybotidae (Diptera, Empidoidea) collected during the Boyekoli Ebale Congo 2010 Expedition in Democratic Republic of Congo, Zootaxa 3603 (1), pp. 1-61 : 25-27

Elaphropeza excavata Grootaert et Shamshev sp. nov.

( Figs. 29–32 )

Material examined. HOLOTYPE, 3 labelled: D.R. CONGO, Kona , 13 May 2010, primary swamp forest (reg. 30038, leg. P. Grootaert, MS reference EC7); Holotype / Elaphropeza excavata / Grootaert et Shamshev sp. nov. ( RBINS). PARATYPES: D.R. CONGO: 1 Ƥ, Yaekela , 2 May 2010, floating reeds on Congo river (reg. 30010, leg. P. Grootaert) ( RBINS).

Diagnosis. Species of E. biuncinata -group; recognised by thorax blackish brown, hind femur brown on apical half; wing with vein R2+3 evenly bowed, pale about middle.

Description. Length: body 1.6 mm, wing 1.5 mm. Male. Occiput entirely black, pollinose (including vertex). Setae brownish yellow to yellow; inner verticals long inclinate, outer verticals short; anterior ocellars long proclinate and cruciate, posterior ocellars short. Frons shining, above antennae about 2.0 times as broad as anterior ocellus. Antenna yellowish brown; pedicel with circlet of subequally short setulae; postpedicel subtriangular, short, 2.0 times longer than wide; stylus with short pubescence, long, 3.5 times longer than postpedicel, 1.8 times as long as scape, pedicel and postpedicel combined. Proboscis brownish yellow. Palpus brownish yellow, small, rounded, bearing scattered setulae, subapical seta hardly prominent.

Thorax entirely blackish brown, largely shining, with yellowish setation. Prothoracic episterna with long upturned seta just above fore coxa. Postpronotal seta hardly prominent. Mesonotum with 2 notopleurals, 1 short postsutural supra-alar, 1 minute postalar and 4 scutellars (apical pair very long, cruciate; lateral pair minute); acrostichals and dorsocentrals undifferentiated, scutum evenly covered with short setae, 1 pair of long prescutellars (nearly as long as notopleurals).

Legs quite robust, almost entirely yellow, hind femur brown on apical half, tarsomere 5 of all legs brownish yellow. Coxae and trochanters with unmodified setation. Fore femur thickened, with rows of short anteroventral and similar posteroventral setae, 2 long setae near base, and short subapical seta anteriorly. Fore tibia lacking prominent bristles (except subapicals). Mid femur slender, with row of short brownish yellow anteroventral and row of similar posteroventral spinules, 1 long pale seta near base and 1 long subapical seta anteriorly. Mid tibia with black ventral spinules, lacking prominent setae (except subapicals). Hind femur and tibia thickened. Hind femur with short anteroventrals and 3 short erect dorsal setae near base. Hind tibia lacking prominent setae; apical projection small, rounded, brownish yellow. Tarsi of all legs unmodified, with unmodified setation.

Wing normally developed, finely infuscate, covered with uniform microtrichia; veins mostly yellowish brown but pale on basal section of M1+2 (including short area beyond crossvein bm-cu), crossvein r-m and middle part of vein R2+3; basal section of vein CuA1 thicker than basal section of vein M1+2. Costal vein with moderately long setulae along anterior margin. Costal bristle moderately long, brownish. Costal index: 22/29/21. Vein Rs somewhat longer than crossvein bm-cu. Vein R2+3 evenly bowed. Veins R4+5 and M1+2 divergent near wing apex, both slightly bowed. Vein CuA1 reaching wing margin. Vein A1 lacking. Crossvein bm-cu slightly oblique. Crossvein r-m somewhat beyond middle of cell bm. Halter blackish.

Abdomen. Tergite 1 represented by very narrow undivided brownish stripe; tergite 2 rather narrow, broadly concave dorsally, with unmodified short setae; tergite 3 broadest, with row of squamiform setae posteriorly; tergites 4 and 5 of similar shape, both narrow, subtriangular viewed laterally, bearing row of squamiform setae posteriorly; tergite 6 broad, subrectangular viewed laterally, with unmodified setation; tergite 7 with basal margin deeply concave, bearing minute posteromarginal setae; tergite 8 unmodified. Sternites 3–5 broadly divided medially, sternites 6 and 7 subrectangular, both with longer setae. Gland-like structure present between tergites 3–4 and 4–5, of complicated structure. Terminalia ( Figs. 29–32 ) rather large, brownish. Cerci separated; right cercus very narrow and short, weakly sclerotised, digitiform, considerably shorter than left cercus, with several unmodified setae of different lengths; left cercus unbranched, long, digitiform in dorsal view, with 2 strong setae subapically ( Fig. 31 ) and numerous unmodified setae of different lengths; hypoproct not prominent. Epandrium completely divided. Right epandrial lamella viewed laterally subrectangular, narrowly attenuated apically, covered with numerous unmodified setae of different lengths. Right surstylus not prominent. Left epandrial lamella fused to hypandrium, with several short setae apically. Left surstylus broadened basally and narrow apically, with 1 strong seta near base and some short unmodified setae ( Fig. 32 ). Phallus long. One rod-shaped apodeme.

Female. Similar to male but mid tibia with hardly prominent ventral spinules; segment 8 rather elongate, dark brown; cercus small, rounded, yellowish brown.

Etymology. The specific epithet refers to the basal excavation of tergite 7.

Distribution. D.R. Congo.

Remarks. In having an entirely black thorax the new species could be compared with E. oribiensis and E. sinikorensis as is been discussed in Remarks to E. angulata sp. nov. The main differences between E. excavata sp. nov. and E. angulata sp. nov. have been given in the key.

Figures

FIGURES 29 – 32. Elaphropeza excavata sp. nov. 29. Right epandrial lamella; 30. Epandrium with cerci; 31. Left cercus; 32. Left surstylus.