Elaphropeza furca, 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 : 90-92

Elaphropeza furca sp. nov.

( Figs. 145–148 )

Diagnosis. Occiput black, postpedicel about 3.0 times longer than wide, style about as long as postpedicel; thorax yellow, acrostichals 2-serial, dorsocentrals 1-serial; legs partly brownish, hind tibia with 1 anterodorsal bristle; abdominal tergites 4 and 5 with squamiform setae.

Description. Male. Body length 1.7–1.9 mm, wing length 1.4–1.5 mm. Occiput wholly black, subshining, with yellow to brownish yellow setation. Anterior ocellars moderately long, proclinate; posterior ocellars shorter. Inner verticals long, outer ones somewhat shorter. Frons subshining. Antenna ( Fig. 145 ) with postpedicel brownish, scape and pedicel yellow. Pedicel with circlet of subequally short setulae. Postpedicel 3.5– 4.0 times longer than wide. Style normally pubescent, brown, somewhat (1.2–1.3 times) longer than post- pedicel and somewhat shorter than scape, pedicel and postpedicel combined. Proboscis brownish yellow. Palpus yellow, small, rounded, with scattered brownish yellow setulae, bearing 1 longer subapical seta.

Thorax almost entirely yellow, shining, with yellow to brownish yellow bristles; metanotum brown in middle, sutures brownish in varying extent. Prothoracic episterna lacking long upturned bristle just above fore coxa, with 1 moderately long bristle in upper part. Postpronotal bristle minute. Mesonotum with 2 notopleural, 1 postsutural supra-alar, 1 postalar and 4 scutellar (inner ones very long, cruciate; outer ones very short) bristles. Acrostichals 2-serial, lacking on prescutellar depression; dorsocentrals 1-serial, extending to base of scutellum, 1 pair of prescutellars longest.

Legs almost entirely yellow, with yellow to brownish yellow setation; fore tibia and tarsus, mid and hind tarsomere 5 brownish. Coxae and trochanters with unmodified setation. Fore and hind femora and tibiae somewhat thickened. Fore femur with rows of short antero- and posteroventral bristles and 2 longer bristles near base. Fore tibia lacking prominent bristles (except subapicals). Mid femur with 2 rows of spinule-like, short, ventral bristles (becoming shorter in apical part of femur), 1 long thin bristle near base and 1 anterior subapical bristle. Mid tibia lacking ventral spinules and prominent bristles (except subapicals). Hind femur bearing 1 row of short anteroventrals and 3–4 erect dorsal bristles near base. Hind tibia with 1 anterodorsal bristle near middle; apical projection small, rounded, clothed in dense brownish setulae. Tarsi of all legs unmodified.

Wing normally developed, finely uniformly infuscate, covered with uniform microtrichia; veins yellowish to brownish yellow. Costal vein with moderately long setulae along anterior margin. Basal costal bristle moderately long, brownish. Costal index: 24/22/24/16. Vein Rs longer than crossvein bm-cu. Veins R4+5 and M1+2 divergent near wing apex, both straight. Vein CuA1 reaching wing margin. Vein A1 absent. Crossvein bm-cu transverse. Crossvein r-m near middle of cell bm. Halter yellow.

Abdomen. Tergites 1–3 and 6–7 brownish, tergites 4 and 5 dark brown. Tergite 1 narrow, subrectangular, divided along midline. Tergites 2 and 3 subtriangular laterally, broadly divided along midline; with unmodified setation. Tergite 4 broadest, with squamiform setae. Tergite 5 very narrow, with squamiform setae. Tergites 6–8 unmodified, tergite 7 with moderately long posteromarginal bristles. Sternites unmodified, weakly sclerotised. Gland-like structures present between tergites 4–5.

Terminalia ( Figs. 146–148 ) large, yellowish brown. Cerci fused forming single, broad, bifurcate lobe bearing long bristles. Epandrium completely divided. Right epandrial lamella subrectangular, covered with numerous long bristles, lacking spines. Right surstylus not prominent. Left epandrial lamella fused to hypandrium, with 2 long bristles apically. Left surstylus with upper lobe large, rather subtriangular, sinuate, with few short bristles. Hypandrium with 1 long and 1 short bristles. Phallus very short. Two rod-shaped apodemes.

Female. Body length 1.7–1.8 mm, wing length 1.5 mm. Segment 8 brownish, elongate, with sclerites separated; sternite 8 folded apically. Cercus brownish. Otherwise as in male.

Material examined: Holotype male labelled: SINGAPORE, Sungei Buloh , 6 July 2005, mangrove, sweeping (reg. 25200, leg. PG, E-20).

Paratypes: 1 ♀, SINGAPORE, Bukit Timah , 16 September 2005, rain forest, Mal 3 (reg. 25348, leg. PG) ; 1 ♀, Bukit Timah , 23 September 2005, rain forest, Mal 3 (reg. 25359, leg. PG) ; 2 ♂♂, 1 ♀, Kranji , 27 July 2005, beach forest, sweeping (reg. 25254, leg. PG) ; 1 ♂, Semakau Island , 26 June 2005, beach, sweeping (reg. 25185, leg. PG) ; 1 ♀, Sungei Buloh , 16 September 2005, mangrove, Mal 2 (reg. 25355, leg. PG) .

Derivatio nominis. The name furca alludes to the bifurcate cerci in the male.

Distribution. Singapore. Forest.

Singapore: This is a rare species (6 records only; 8 individuals). On several occasions it was found in anthropogenic conditions: the park at Kranji, the beach forest at the landfill of Semakau island and a patch of secondary forest at Bukit Timah. The species was only twice recorded in more natural conditions at Sungei Buloh: once by sweep netting and once in a Malaise trap. Future studies might show if it is a colonizer and possibly much more widespread. The sex ratio is 1/1.

Remarks. The relationships of E. furca 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 145–148. Elaphropeza furca sp. nov. 145. antenna. 146. epandrium with cerci. 147. right epandrial lamella. 148. left surstylus.