Elaphropeza ngi, 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 : 98-100

Elaphropeza ngi sp. nov.

( Figs. 162–165 )

Diagnosis. Occiput and antenna yellow, postpedicel short about 2.0 times longer than wide; scutum with indistinct brownish spot above wing base; tarsomere 5 of all legs brownish, hind tibia bearing 1 anterodorsal bristle.

Description. Male. Body length 2.2–2.5 mm, wing length 1.8–1.9 mm. Occiput yellow, indistinctly darkened in upper part, subshining, with yellow to brownish yellow setation. Eye deeply concave on posterior margin. Anterior ocellars long, proclinate; posterior ocellars minute. Inner verticals long, outer ones short. Antenna ( Fig. 162 ) wholly yellow (postpedicel appearing somewhat darker). Pedicel with circlet of subequally short setulae. Postpedicel about 2.0 times (1.75 in holotype) longer than wide. Style normally pubescent, brownish yellow, about 6.0 times longer than postpedicel and nearly 3.0 times as long as scape, pedicel and postpedicel combined. Proboscis brownish yellow. Palpus yellow, small, rounded.

Thorax almost entirely yellow, shining, with yellow to brownish yellow bristles; scutum with indistinct brownish spot above wing base, metanotum somewhat brownish yellow posteriorly, sutures brownish in varying extent. Prothoracic episterna lacking long upturned bristle just above fore coxa, with 2–3 very short bristles 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 and dorsocentrals multiserial, uniform, the former lacking on prescutellar depression, the latter extending to base of scutellum (1 pair of long prescutellars).

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

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 long, yellow. Costal index: 48/25/38/17. Vein Rs somewhat longer than crossvein bm-cu. Vein R2+3 smoothly arched. Veins R4+5 and M1+2 slightly divergent near wing apex, both straight. Vein CuA1 not quite reaching wing margin. Vein A1 absent. Crossvein bm-cu almost transverse. Crossvein r-m somewhat before middle of cell bm. Halter with dark knob.

Abdomen. Tergite 1 entirely pale yellow. Tergites 2 and 3 brownish, subtriangular and of subequal width viewed laterally, otherwise pale yellow, broadly concave anteriorly, divided along midline; with unmodified setation. Tergite 4 broadest, dark brown, with squamiform setae. Tergite 5 very narrow, dark brown, with squamiform setae. Tergites 6 and 7 of subequal width, yellow, the former with minute, the latter with moderately long posteromarginal bristles. Segment 8 unmodified. Sternites very weakly sclerotised. Gland-like structures between tergites 4 and 5.

Terminalia ( Figs. 163–165 ) large, brownish yellow. Cerci broadly separated, covered with moderately long bristles, lacking spines; left cercus digitiform, long; right cercus short, with less numerous bristles. Epandrium completely divided. Right epandrial lamella ( Fig. 164 ) subtriangular, greatly produced in apical part, covered with numerous bristles of different lengths. Right surstylus hardly prominent. Left epandrial lamella fused to hypandrium, with 1 long bristle apically. Left surstylus with upper lobe large, subglobular, deeply broadly concave on upper margin, with several long bristles. Hypandrium with 1 very long and 1 very short bristles. Phallus very short. Two rod-shaped apodemes.

Female. Unknown.

Material examined: Holotype male labelled: SINGAPORE, Nee Soon , 14 December 2005, swamp forest, Mal 3 (reg. 25448, leg. PG, E-43).

Paratypes: SINGAPORE, 1 ♂, Nee Soon , 3 December 2005, swamp forest, Mal 2 (reg. 25437, leg. PG) .

Derivatio nominis. This species is dedicated to Prof. Dr. Peter Ng, director of the Raffles Museum for Biodiversity Research in Singapore and a driving force in biodiversity studies.

Distribution. Singapore. Forest.

Singapore: This is a very rare species, only known from two males .

Remarks. The relationships of E. ngi sp. nov. are unclear beyond inclusion within the E. ephippiata species group. The main distinguishing features of the new species are indicated in the key. Additionally, E. ngi sp. nov. appears to resemble E. fujianensis Yang and Yang described from China ( Yang and Yang 2003). However, in E. fujianensis the scutellum is yellow (vs. brownish in the new species).

Figures

FIGURES 162–165. Elaphropeza ngi sp. nov. 162. antenna. 163. epandrium with cerci. 164. right epandrial lamella. 165. left surstylus.