Platypalpus nuadkhao, Grootaert & Shamshev, 2006

Grootaert, Patrick & Shamshev, Igor, 2006, The genus Platypalpus Macquart (Diptera: Hybotidae) from Northeast Thailand with comments on the species groups in the Oriental region, Journal of Natural History 39 (47), pp. 4031-4065 : 4032-4035

Platypalpus nuadkhao sp. nov. (male and female)

( Figures 1–3 )

Etymology

The name ‘‘nuadkhao’’ refers to the white arista (in Thai language ‘‘nuad’’ means ‘‘arista’’, ‘‘khao’’ means ‘‘white’’).

Diagnosis

Mostly yellow (including legs) species; one pair of short verticals; antenna brownish, arista white, postpedicel nearly 5.0 times longer than wide; mesonotum with two triangular brown spots, sternopleuron, hypopleuron and metapleuron largely brown; tarsomeres 3–5 of all legs darkened, mid femur twice broader than fore femur.

Material examined

Holotype: male, Thailand, Loei province, Na Haeo , FIRS, 5–11 June 2003, Malaise trap (2), leg. P. Grootaert and Siriluck (in RBINS) . Paratypes: one female, Thailand, Loei province, Na Haeo , 5–11 June 2003, Malaise trap (2), leg. P. Grootaert and Siriluck Intarasri ; one female, 30 April to 7 May 2000, Malaise trap, leg. P. Grootaert.

Male

Body length 2.9 mm; wing length 2.9 mm.

Head. Black in ground-colour. Occiput finely greyish pollinose, subshining, with scattered black bristles in upper part, including two hardly prominent verticals, and some pale bristly hairs in lower part. Ocellar tubercle with two very short thin bristles. Frons shining, mostly very narrow, narrower than anterior ocellus, somewhat widened above. Face concolorous with frons. Antenna almost wholly brownish, postpedicel paler at apex; arista missing (2.5 times longer than postpedicel in female). Postpedicel narrow, elongate conical, nearly 5.0 times longer than wide. Palpus wholly yellow, mostly with scattered, short, yellow bristly hairs, bearing one longer brownish subapical bristle.

Thorax. Largely yellow; mesonotum with two triangular brown spots on supra-alar space near scutellum; almost wholly (except for yellowish upper posterior corner) dark brown, hypopleuron largely brown (yellowish to yellowish brown in upper part), metapleuron brown; postnotum with metanotum brownish yellow and metapleuron brown. Mesonotum and sternopleuron shining, otherwise thorax finely pollinose, subshining. Anterior and posterior spiracles brown. Humerus with few minute setulae. Mesonotum with brownish yellow, short, inconspicuous setation including two notopleural (anterior one shorter and thinner), one postalar, and four scutellar (inner ones longer and stronger) bristles; some scattered setulae present behind humerus, on notopleural depression, supra-alar space and postalar callus. Acrostichals lacking. Dorsocentrals arranged in one row, few in number, mostly of subequal length (except for one longer prescutellar pair).

Legs. Almost wholly yellow, only tarsomeres 3–5 somewhat darkened (more distinct on fore leg). Coxae and trochanters with ordinary yellow to brownish yellow setae. Fore femur slender, with a row of brownish yellow, thin, posteroventral bristles (one longest one near middle of femur longer than femur is deep) and a row of yellowish, short (nearly half as long as femur is deep), thin, anteroventral bristles. Fore tibia mostly slender, swollen near tibial gland; mostly clothed with ordinary setulae, with few more prominent, dorsal, brownish setae. Fore tarsus slender, unmodified. Mid femur incrassate, nearly 2.0 times broader than fore femur; with rows of ventral spinules and a row of rather long (nearly as long as femur is deep), brown, posteroventral bristles. Mid tibia with black ventral spinules throughout and hardly prominent flattened apical spur. Hind leg long and slender; hind femur somewhat swollen in apical part anteriorly, bearing a row of short, brownish to brownish yellow, erect, antero- and a row of short, pale, posteroventral bristles.

Wing. Slightly infuscate; basicostal bristle missing. Vein M1+2 somewhat bowed in apical part but parallel to vein R4+5 near wing-apex. Crossveins m-cu and r-m contiguous. Cell br broader than cell bm. Vein CuA2 somewhat sinuate, recurrent. Vein A1 long. Squama brownish yellow and with long brownish yellow fringes. Halter pale yellow.

Abdomen. Shining, mostly with scattered setulae; pregenital segments with long bristles. Tergites brown; sternites mostly yellowish, sternite two brownish along posterior margin, sternites of pregenital segments brownish yellow.

Terminalia. Brown, small, subglobular. Left epandrial lamella ( Figure 2 ) pointed toward apex, clothed with numerous long bristles. Right epandrial lamella ( Figure 3 ) subrectangular, with several long bristles in upper part and ventrally. Right surstylus small, subtriangular. Cerci ( Figure 1 ) digitiform, slender, clothed with scattered short bristles, pubescent; left cercus about 1.5 times longer than right cercus, somewhat broadened in basal part. Hypoproct ( Figure 1 ) somewhat enlarged, not extending beyond apices of cerci, lacking spine-like extensions.

Female

Body length 2.8–3.1 mm; wing length 2.7–3.0 mm.

Arista thick, white pubescent, nearly 2.5 times longer than postpedicel. One long, brownish, basicostal bristle. Otherwise as in male except for sexual differences. Cerci brownish yellow.

Distribution

Thailand.

Remarks

In having the yellow mesonotum with two relatively small brownish spots P. nuadkhao sp. nov. should be compared with P. thaicus sp. nov., P. siamensis sp. nov., and P. isaanensis sp. nov. described in the present paper. P. thaicus sp. nov. and P. siamensis sp. nov. differ from the new species primarily by more slender mid femur (1.5 times broader than fore femur and 2.0 times broader than fore femur, respectively). P. isaanensis sp. nov. appears to be the closest ally to the new species. However, it has shorter postpedicel, a wholly brown sternopleuron and different male terminalia. P. candidiseta (Bezzi) (known from a female taken in Taiwan only) differs from P. nuadkhao sp. nov. by wholly yellow mesonotum and wholly black thoracic pleura ( Bezzi 1912). P. nepalensis (Brunetti) (known from Nepal also has mesonotum with two small spots) possesses pale yellowish grey pubescence on the occiput, wholly grey thoracic pleura, uniformly pale brownish yellow legs and rather large male terminalia ( Brunetti 1913, 1920). P. sanguinolentus Melander (known after a female taken from Java only) can be readily distinguished from the new species by the wholly yellow mesonotum and black scutellum ( de Meijere 1914).

Figures

Figures 1–3. Platypalpus nuadkhao sp. nov., male. (1) Epandrium with cerci and hypoproct. (2) Left epandrial lamella (lateral view). (3) Right epandrial lamella (lateral view). Scale bar: 0.1 mm.