Strongylophthalmyia elongata sp. nov.

(Figs 3–8, 26, 30)

Type material. Holotype. CHINA: ♂, Yunnan, Yulong, Mingyin, Jiazi, 2818 m, 17 Jun. 2020, Zhuo Chen leg. (CAU) . Paratypes. CHINA: 1♂ 2♀♀, Yunnan, Yulong, Baisha, Wenhai, 3099 m, 16 Jun. 2020, Zhuo Chen leg. (CAU) . 1♂, Yunnan, Yulong, Baisha, Geleba, 3005 m, 16 Jun. 2020, Weidong Huang leg. (CAU) . 1♂ 1♀, Yunnan, Shangri-la, Hongshan Forest Farm, 3279 m, 11 Jun. 2012, Yuyu Wang leg. (CAU) .

Diagnosis. Generally shining blackish brown (Figs 3, 4); face yellowish brown, parafacial yellow; antennal arista blackish brown (Fig. 26); wing slightly infumate, with large dark patch at apex and broad median transverse band, both much darkened in cell r 2+3 (Fig. 30); legs mostly yellow, with mid and hind femora dark brown apically, basal third of mid and hind tibiae dark brown; phallapodeme curved inwardly in apical half (Fig. 8); distiphallus about 1.73 times as long as phallapodeme, with hook-like sclerotized apical “glans” (Figs 7, 8).

Description. Male (Fig. 3) and female (Fig. 4). Body length 4.5–5.6 mm, wing length 4.1–4.6 mm.

Generally shining blackish brown (Figs 3, 4). Face yellowish brown; parafacial yellow. Antenna yellow with arista blackish brown (Fig. 26). Clypeus whitish in male, dark brown in female; proboscis and palpus blackish brown. Basisternum dark brown. Wing slightly infumate, with large dark patch at apex and broad median transverse band at level of dm-m, both much darkened in cell r 2+3 (Fig. 30); wing veins brown to dark brown. Halter white. Legs mostly yellow; mid and hind femora dark brown apically (indistinct on fore femur); basal third of mid and hind tibiae dark brown; tarsomeres 1–3 dark yellow, tarsomeres 4 and 5 dark brown (Figs 3, 4).

Head with frons slightly inflated; parafacial with dense silvery tomentose stripe; gena with silvery tomentose stripe along eye margin; postgena bulging, with several long black setulae. Head chaetotaxy: 1 inner vertical seta, 1 outer vertical seta, 2 fronto-orbital setae, 1 ocellar seta, 1 postocellar seta. Clypeus band-like in male, thick and anteriorly protruding in female; palpus elongate, with dense, short and long, dark setulae. Antennal scape with scattered marginal setae and 1 dominant dorsal seta; pedicel with single strong seta dorsally; first flagellomere ovate, wider than long, densely covered with short white setulae (Fig. 26).

Thorax elongate; mesonotum covered with scattered short golden setulae, in dorsal view with distinct transverse suture. Anepisternum with short setulae on posterior half. Scutellum subtriangular, slightly inflated. Thoracic chaetotaxy: 1 postpronotal seta, 1 anepisternal seta, 1 notopleural seta, 1 dorsocentral seta, 1 posterior supra-alar seta, 1 scutellar seta. Wing (Fig. 30) with R 4+5 and M 1+2 almost parallel apically; apical section of M 1+2 slightly arched; M 4 and CuA+CuP not reaching but closely approaching wing margin; r-m located about basal 0.41 of cell dm; apical section of M 4 much shorter than dm-m; alula small; anal lobe slightly narrowed. Legs with dense dark setulae; fore coxa with several short and long setulae anterodorsally.

Abdomen covered with dense long setae. Tergite 1 weakly sclerotized. Pregenital sclerites relatively weakly sclerotized.

Male genitalia: Epandrium (Figs 5, 6) relatively long and narrow, with dense long setae. Surstylus (Figs 5, 6) broadly expanded apically, with dense short stout setae on inner distal surface. Cerci (Figs 5, 6) narrow basally, rounded apically, with one long seta and several short setae in apical half. Hypandrium (Figs 7, 8) narrow, with one pair of bifid anterior lobes. Phallapodeme (Fig. 8) long, curved inwardly in apical half. Pregonite (Figs 7, 8) long, narrow, band-like, basally fused to inner surface of hypandrium. Phallic plate (Figs 7, 8) thickened, divided into two articulating sclerites. Distiphallus (Figs 7, 8) extremely long, about 1.73 times as long as phallapodeme, with sclerotized hook-like apical “glans”, membrane microtrichose. Ejaculatory apodeme long, thickened in basal half and slender in apical half.

Etymology. The specific epithet is derived from Latin elongata, referring to the relatively elongate body shape of this new species.

Distribution. China (Yunnan).

Comparative notes. Strongylophthalmyia elongata sp. nov. is similar to S. angusticollis Frey, 1956 (Myanmar, Vietnam) in the elongate body shape. The syntypes of the latter species deposited in MZH, including a male and two females, were examined during the present study. The new species can be distinguished from S. angusticollis by the following character states: frons uniformly blackish brown (yellow in anterior quarter or third in S. angusticollis); antennal arista blackish brown (yellowish brown in S. angusticollis); basisternum dark brown (vs. yellow or with paired yellow spots in S. angusticollis); apical spot and median transverse band on wing much darkened in cell r 2+3 (such patterns uniform in color in S. angusticollis). The male genitalia of S. angusticollis have not been studied in detail. The difference in male genital characters between these two species needs to be checked in the future.