Elaphropeza yeoi, Published, 2007

SHAMSHEV, IGOR V. & GROOTAERT, PATRICK, 2007, Revision of the genus Elaphropeza Macquart (Diptera: Hybotidae) from the Oriental Region, with a special attention to the fauna of Singapore, Zootaxa 1488 (1), pp. 1-164 : 64-66

Elaphropeza yeoi sp. nov.

( Figs. 95–98 )

Diagnosis. Species with black thorax, very similar to E. neesoonensis sp. nov. but tarsomere 5 black and different terminalia.

Description. Male. Body length 1.3–1.4 mm, wing length 1.2–1.3 mm. Head black, occiput subshining, with pale setation. Eye with hind margin slightly concave. Anterior ocellars moderately long, proclinate; posterior ocellars minute. Two pairs of inclinate verticals (inner ones longer). Frons shining. Antenna ( Fig. 95 ) wholly brownish. Pedicel with circlet of equally minute setulae. Postpedicel nearly 5.5 times longer than wide. Style normally pubescent, brown, nearly as long as postpedicel but 1.3–1.5 times shorter than scape, pedicel and postpedicel combined. Proboscis brownish yellow. Palpus yellow, small, rounded; with scattered yellow setulae, including 1 longer subapical one.

Thorax entirely black, shining, with yellow to brownish yellow bristles. Proepisternum lacking long upturned bristle just above fore coxa, with 1 short bristle in upper part. Postpronotal bristle minute. Mesonotum with 1 very short presutural supra-alar, 3 notopleural (posterior one longer), 1 postsutural supra-alar, 1 postalar and 4 scutellar (inner ones very long, cruciate; outer ones very short) bristles. Acrostichals prominent in anterior part of scutum only, 2–3 pairs, rather short. Dorsocentrals prominent in posterior part of scutum only, 3 pairs, prescutellars longest.

Legs almost entirely yellow, tarsomere 5 of all legs black. Coxae and trochanters with unmodified setation. Fore femur somewhat thickened, with hardly prominent rows of antero- and posteroventral bristles and 1 long bristle near base. Fore tibia lacking prominent bristles (except subapicals). Mid femur slender, with 2 rows of brownish yellow, spinule-like, short, ventral bristles, 1 long yellow thin bristle near base and 1 anterior subapical bristle. Mid tibia with 1 row of black ventral spinules, lacking prominent bristles (except subapicals). Hind femur slender, bearing 1 row of short anteroventrals and 2–3 erect dorsal bristles near base. Hind tibia somewhat thickened at apex, with ordinary inconspicuous setation; apical projection small, rounded, clothed in dense brownish setulae. Tarsi of all legs unmodified.

Wing normally developed, uniformly finely infuscate, covered with uniform microtrichia; veins yellowish to brownish yellow. Costal vein with moderately long setulae along anterior margin. Basal costal bristle moderately long, yellow. Costal index: 19/17/28/14. Veins R4+5 and M1+2 divergent near wing apex, both straight. Vein CuA1 not quite reaching wing margin. Crossvein bm-cu transverse. Crossvein r-m near middle of cell bm. Halter yellow.

Abdomen. Tergite 1 narrow, undivided, with few minute setulae laterally. Tergites 2 and 3 of subequal width and about 1.5 times broader than tergite 1, with scattered unmodified setae laterally. Tergite 4 broad, nearly as broad as tergites 2 and 3 combined, darker, with unmodified setae. Tergite 5 very narrow, bearing squamiform setae. Tergites 6 and 7 unmodified, tergite 6 with short while tergite 7 with moderately long posteromarginal bristles. Sternites unmodified. Gland-like structures present between tergites 4 and 5, represented by 2 large ovate sclerites covered with numerous microtrichia.

Terminalia ( Figs. 96–98 ) brown, elongate. Cerci fused forming single digitiform sinuate long lobe covered with several moderately long bristles. Epandrium completely divided. Right epandrial lamella subtriangular, with deep excision at apex, covered with long bristles. Right surstylus not prominent. Left epandrial lamella fused to hypandrium, with 2 short bristles apically. Left surstylus with upper lobe elongate, rather broad and parallel-sided on about basal 2/3, narrowed toward apex on apical 1/3. Hypandrium with 2 subapical bristles. Phallus very short. Two rod-shaped apodemes.

Female. Body length 1.6 mm, wing length 1.5 mm. Mid tibia lacking ventral spinules. Segment 8 elongate, with sclerites separated; sternite 8 folded apically. Cercus brownish yellow. Otherwise as in male.

Material examined: Holotype male labelled: SINGAPORE, Nee Soon , 4 December 2002, swamp forest, sweeping (reg. 22052, leg. PG, E-07).

Paratypes: SINGAPORE: 1 ♀, Chek Jawa , 26 October 2005, mangrove, Mal 2 (reg. 25399, leg. PG) ; 1 ♂, Nee Soon , 3 December 2003, marshland, sweeping (reg. 23100, leg. PG) ; 1 ♂, Nee Soon , 5 August 2005, swamp forest, sweeping (reg. 25286, leg. PG) .

Derivatio nominis. Elaphropeza yeoi sp. nov. is dedicated to Mr. K.L. Yeo who offered a lot of assistance in the field.

Distribution. Singapore. Marshy land in swamp forest and occasionally in mangrove.

Singapore: This is a rare species (only 4 records and 4 specimens). It was collected by sweep netting the grasses in the marshy land at Nee Soon. There is a single record in a Malaise trap in the mangrove at Chek Jawa. The records range from August until December .

Remarks. The relationships of E. yeoi sp. nov. are unclear beyond inclusion within the monophyletic lineage of Elaphropeza sharing completely fused cerci (see “Discussion” for details).

Figures

FIGURES 95–98. Elaphropeza yeoi sp. nov. 95. antenna. 96. epandrium with cerci. 97. apical part of right epandrial lamella and cercus. 98. left surstylus.