Xenoplatyura sichuanensis Cao et Xu, n. sp.

Xenoplatyura sichuanensis Cao et Xu, n. sp.

(Figs. 1, 4–7)

Diagnosis. This species is similar to X. autumna Chandler, 1994 in having a faint dark shade at apex of wing and the shape of tergite IX. However, it is easily distinguished by the distance between tips of R1 and R4 being 1.6–1.8 times as long as R4 (0.3 times in X. autumna). The shape of gonocoxites and gonostyli are also good characters to distinguish it from the other three Chinese species of the genus.

Description. MALE. Lengths: Body: 5.9 mm; wing: 4.4 mm.

Head. Vertex and occiput yellowish brown with fairly dense small black recumbent hairs. Frons obscurely yellow. Antennae: scape and pedicel cup-shaped, obscurely yellow. Flagellum: segment I obscurely yellow; remaining segments dark brown. Face yellow. Palpi: segments I–II yellowish brown, segments III–IV pale brown; segment IV long and slender. Labellum yellowish brown, fleshy.

Thorax. Mesonotum yellowish brown with yellow on humeral area and side margins; long dark setae on side margins. Scutellum yellowish brown with long setae on posterior margin. Prothorax yellow with some long setae. Anepisternum pale brown, bare; katepisternum anteroventrally yellowish brown, remainder of katepisternum yellow. Laterotergite and mediotergite yellowish brown, bare. Halter yellow, knob yellow with brown dorsally.

Legs. Yellow. Fore coxa, apex of mid and hind coxae with long recumbent black hairs. Femora with recumbent black hairs. Fore and mid tibiae with setulae in rows on apical half, hind tibia with setulae in rows on apical third. All tibiae with some setae. Fore tibia without comb, mid tibia with posterior comb and hind tibia with anterior and posterior combs. Tibial spurs dark brown. Fore and mid basitarsi subequal in length to lengths of their respective tibiae, hind basitarsus 0.7x length of hind tibia. Claws minute.

Wing (Fig. 1). Hyaline with faint infuscation discernible below tip of R5. Veins dark brown. Costa almost reaching one-third distance from vein R5 to vein M1+2; Sc ends slightly beyond base of Rs; Sc-R situated at level of basal 0.2–0.3 of distance between h and tip of Sc. Distance between tips of R1 and R4 1.6–1.8 times as long as R4. Ratio of radiomedial fusion / petiole of M: 0.5–0.6. Petiole of M one-fifth as long as length of M1+2. Veins M2 and CuA1 not reaching wing margin, vein A reaches wing margin.

Abdomen. Tergites I–VI obscurely yellow, tergites VII–VIII yellowish brown; all of the tergites with dense recumbent black hairs. Sternum patterned as on tergites.

Hypopygium (Figs. 4–7). Tergite IX (Figs. 5, 6) brown, broad and slightly elongated; cercus visible in dorsal view. Genitalia as in Figs. 4, 5, 7.

FEMALE. Unknown.

Types. Holotype ɗ (ZJFC 060245) and paratype ɗ from: China: Sichuan Province: Wolong National Natural Reserve, 21 July 2006, Jian Cao; Other paratypes: 1ɗ, Sichuan Province: Emei Mountain, 2 August 2006, Jian Cao.

Etymology. The species epithet derives from the place name Sichuan, referring to the type locality of the species.