Elaphropeza meieri, 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 : 76-78

Elaphropeza meieri sp. nov.

( Figs. 117–120 )

Diagnosis. Species with entirely black thorax; postpedicel long, about 4.0 times longer than wide; acrostichal and dorsocentral bristles few in number; fore tarsomeres 2–5 distinctly dark brown annulated; hind tibia with 1 anterodorsal bristle.

Description. Male. Body length 1.8–2.1 mm, wing length 1.5–1.6 mm. Head black, occiput subshining, with pale setation. Eye with hind margin slightly concave. Anterior ocellars long, proclinate; posterior ocellars minute. Two pairs of inclinate verticals (inner ones longer). Frons shining. Antenna ( Fig. 117 ) wholly brownish. Pedicel with circlet of equally minute setulae. Postpedicel about 4.0 times (3.8 in holotype) longer than wide. Style normally pubescent, brown, nearly 1.5 times longer than postpedicel and about as long as scape, pedicel and postpedicel combined. Proboscis brownish yellow. Palpus yellow, small, rounded; with scattered yellow setulae.

Thorax entirely black, shining, with yellowish brown 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 (2 equally long), 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, 3–4 pairs, rather short. Dorsocentrals 1-serial, 5 per row, anterior ones nearly as long as acrostichals, 2 prescutellar pairs longer.

Legs largely yellow, fore tibia and fore tarsomere 1 yellowish brown, tarsomeres 2–5 distinctly dark brown annulated leaving only extreme base yellow, mid and hind tarsus with tarsomeres 2–5 brownish yellow. 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 in basal 2/3 (posteroventrals somewhat longer), 1 long yellow thin bristle near base and 1 anterior subapical bristle. Mid tibia with 1 row of black ventral spinules (apical one longer), lacking prominent bristles (except subapicals). Hind femur rather slender, bearing 1 row of short anteroventrals and 2–3 erect dorsal bristles near base. Hind tibia somewhat thickened at apex, bearing 1 long anterodorsal bristle near middle; apical projection small, rounded, clothed in dense brown setulae. Tarsi of all legs unmodified.

Wing normally developed, 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, yellowish brown. Costal index: 26/26/29/14. Veins R4+5 and M1+2 somewhat 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, brownish, with scattered setulae laterally. Tergites 2 and 3 nearly 1.5 times broader than tergite 1, of subequal width, with unmodified setation. Tergite 4 nearly 2.5 times broader than tergite 3, covered with unmodified setae. Tergite 5 very narrow, bearing squamiform setae. Tergites 6 and 7 ordinary, tergite 6 with short while tergite 7 rather with long posteromarginal bristles. Sternites unmodified, with scattered minute setulae. Gland-like structures present between tergites 4 and 5, including 2 narrow anterior sclerites and 2 large, densely covered with short microtrichia posterior sclerites.

Terminalia ( Figs. 118–120 ) dark brown, elongate, rather small. Cerci fused forming digitiform, narrow, long lobe covered with several moderately long bristles. Epandrium completely divided. Right epandrial lamella subtriangular, truncate at apex, with numerous long bristles. Right surstylus not prominent. Left epandrial lamella fused to hypandrium, with 2 short bristles apically. Left surstylus with upper lobe long, digitiform, with deep narrow excision on apex and scattered very short bristles. Hypandrium with 1 long and 1 short bristles apically. Phallus very short. Two rod-shaped apodemes.

Female. Body length 1.8–1.9 mm, wing length 1.5–1.6 mm. Mid tibia lacking ventral spinules. Otherwise as in male. Segment 8 elongate, with sclerites separated; sternite 8 folded apically. Cercus brownish.

Material examined: Holotype male labelled: SINGAPORE, Nee Soon , 19 April 2005, swamp forest, sweeping (reg. 25070, leg. PG, E-05).

Paratypes: SINGAPORE: 1 ♂, Chek Jawa , 2 December 2003, mangrove, Mal 1 (reg. 23097, leg. PG) ; 1 ♂, 1 ♀, Nee Soon , 4 December 2002, swamp forest, sweeping (reg. 22054, leg. PG) ; 2 ♂♂, 1 ♀, Nee Soon , 25 November 2003, swamp forest, sweeping (reg. 23086, leg. PG) ; 2 ♂♂, Nee Soon , 3 December 2003, marshland, sweeping (reg. 23100, leg. PG) ; 1 ♂, Nee Soon , 9 March 2005, swamp forest, sweeping (reg. 25005, leg. PG) .

Derivatio nominis. The species is dedicated to A/Prof. Dr. Rudolf Meier, head of the Evolutionary Biology lab at National University of Singapore.

Distribution. Singapore. Open marshy land in forest. Occasionally in mangrove.

Singapore: This is a rare species with only six records. It is observed in open marshy areas in the swamp forest where it was collected by sweeping only. It was not recorded in the Malaise traps. There is a single record of a male in the Malaise trap in the mangrove at Chek Jawa. A sex ratio of 0.25/ 1 females to males indicates a different activity pattern for females and males. The activity period is from the end of November until March .

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

Figures

FIGURES 117–120. Elaphropeza meieri sp. nov. 117. antenna. 118. epandrium with cerci. 119. right epandrial lamella. 120. left surstylus.