Holotype male (QAU), China, Zhejiang Province, Lin’an District, Mount Tianmushan, 2019.V.15, Xiao Zhang.

Wing marked with two brown bands. Epandrium bilobed, each lobe strongly elongated and forming a long surstylus, surstylus broadest at base, tapering and curved downward distally to middle, curving up at tip. Gonostylus with four projections and lobes. Hypandrium rectangular, posterior margin with a V-shaped projection bearing dense long hairs posteriorly, a triangular projection bearing dense short hairs laterally and a pair of elliptic projections bearing dense long hairs posteriorly.

Male. Body length 7.0 mm, wing length 8.0 mm.

Head mostly dark brown, except gena yellow with a black elliptical spot intermediately; clypeus yellow; hairs on head dark brown. Compound eyes black without pubescence. Antenna with scape, pedicel and basal half of 1^st flagellomere yellow, other flagellomeres light brown, hairs on antenna brown. Proboscis yellow with brown hairs. Palpus yellow with last segment light brown, hairs brown.

Thorax (Fig. 2b). Pronotum yellow. Propleuron yellow. Mesonotum mostly dark brown with middle area of scutellum yellow and lower half of laterotergite yellow. Mesopleuron uniformly yellow. Coxae and trochanters yellow; fore femur yellow and gradually darkened apically; mid and hind femora yellow with brown ring apically; tibiae yellow with brown ring apically; 1^st tarsomere yellow brown and gradually darkened apically, 2^nd to 5^th tarsomeres uniformly dark brown. Hairs on legs brown. Relative length of 1^st to 5^th tarsomeres in hind leg as 11.2 : 2.8 : 1.6 : 1 : 1. Wing (Fig. 2c) 3.4 times as long as wide, subhyaline, marked with two brown bands as follows: median band broad and distinct, extending from basal part of cell r₂₊₃ to fork of CuA; subapical band extending from anterior margin of wing, covering tip of R₁ and R₂, fork of R₄₊₅, and extending to fork of M₁₊₂, slightly separated into three marks. Veins brown; Sc ending in C not at level of basal third of R₂₊₃; Rs straight, as long as r-m. Haltere and prehaltere pale yellow with brown hairs.

Figure 2. 

Ptychoptera tianmushana sp. nov. a habitus of male, lateral view b thorax, dorsal view c wing. Scale bars: 2.0 mm (a); 0.5 mm (b); 1.0 mm (c).

Abdomen. First tergum brown, 2^nd tergum brown with middle quarter area yellow, 3^rd and 4^th terga pale yellow with caudal third brown, 5^th to 7^th terga uniformly brown. Sterna pale yellow. Hairs on abdomen brown.

Male genitalia yellow. Epandrium (Fig. 3b) bilobed, each lobe strongly elongated and forming a long surstylus, surstylus broadest at base, tapering and curved downward distally to middle, curving up at tip, with brown hairs; proctiger with short hairs. Gonocoxite (Fig. 3c) long and stout, 3 times as long as wide, basal apodeme two-thirds as long as gonocoxite; paramere with a pair of hook-shaped projections and a pair of conical projections. Gonostylus (Fig. 3c) with four projections and lobes: a strong retrose basal projection on inner side with tip bilobate; a broad tongue-shaped lobe on middle area with several long hairs apically; a dumbbell-shaped apical lobe broad basally with uniformly short hairs, apical with dense short setae; an apical hooked projection with several long hairs. Hypandrium (Fig. 3d) rectangular, anterior margin concaved medially, posterior margin with a V-shaped projection bearing dense long hairs posteriorly, a triangular projection bearing dense short hairs laterally and a pair of elliptic projections bearing dense long hairs posteriorly. Aedeagus (Fig. 3e, f): subapical sclerite tongue-shaped, slightly caved bilaterally, apex of subapical sclerite round; subapical sclerite serrated with five teeth when viewed from lateral side.

Figure 3. 

Ptychoptera tianmushana sp. nov. a male genitalia, lateral view b epandrium, dorsal view c gonocoxite and gonostylus, dorsal view d hypandrium, ventral view e aedeagus, anterior view f aedeagus, lateral view. Scale bars: 0.2 mm.

Female. Unknown.

China (Zhejiang).

The species is named after the type locality Mount Tianmushan.

This new species is very similar to P. emeica from China but can be separated from it by the 6^th and 7^th sterna of abdomen being yellow, the tip of the surstylus being curved up when viewed from the lateral side, the tip of the retrose basal projection on inner side being bilobate, the paramere having a pair of hook-shaped projections and a pair of conical projections, and the subapical sclerite of aedeagus being serrated with five teeth. In P. emeica, the 6^th and 7^th sterna of abdomen are mostly brown, the tip of the surstylus is not curved up when viewed from the lateral side, the tip of the retrose basal projection on inner side is not bilobate, the paramere have a pair of slender L-shaped projections, and the subapical sclerite of aedeagus is serrated with two teeth (Kang et al. 2019). In ecology, they live together with similar habitat. The adult of P. tianmushana was collected on the plants in close to streams and adults of P. emeica often found at the margins of streams or in wet forests. This new species is also similar to P. formosensis from China and Japan but can be separated from it by the 5^th and 6^th terga of abdomen being dark brown, the tip of the surstylus being curved up, the tip of the retrose basal projection on inner side being bilobate, the tip of gonostylus having a hook-shaped ventral lobe. In P. formosensis, the 5^th and 6^th terga of abdomen are mostly yellow, the tip of the surstylus is not curved up, the tip of the retrose basal projection on inner side is not bilobate, the tip of gonostylus have a digitiform ventral lobe (Alexander 1924; Nakamura and Saigusa 2009).

Paratypes: 2 females (USNM), China: Jiangxi Province, Xunwu District, Hong San (1000–1053 m), 1936.VI.27–28, Judson Linsley Gressitt. Other material: 1 female (USNM), China: Zhejiang Province, Deqing District, Mount Moganshan, 1936.V.29, Père Octave Piel.

General coloration black. Haltere black with base of stem yellow. Wing with heavily brown bands and marks as follows: a large triangular brown mark in base of cells R and M; a irregular quadrate brown mark at origin of Rs; an elliptic brown mark at midlength of CuA₁; a small oval brown mark at tip of A; median band extending from R to the bend in distal section of CuA₂; subapical band extending from anterior margin of wing, covering tip of R₁ and R₂, to tip of M₂; Rs about three-fifths the length of R₄₊₅, 4 times the length of r-m.

China (Jiangxi, Zhejiang).

The determined specimen of this species collected from Zhejiang was identified by Alexander in 1939, but was not officially published to record. We re-determined it during the study and now record this species from Zhejiang for the first time. For descriptions and illustrations of this species, see Alexander (1937) and Krzeminski and Zwick (1993).

Figure 4. 

Ptychoptera bellula Alexander, 1937 a habitus of one paratype, lateral view b habitus of the other paratype, lateral view c–f one female identified by Alexander (c habitus of female, lateral view d one leg e wing f collection and identification labels). Scale bars: 2.0 mm (a–d); 1.0 mm (e).

Holotype male (CAU), China: Zhejiang Province, Anji District, Mount Longwangshan, 1996.VI.12, Chikun Yang.

Thorax mostly black. Wing marked with two brown marks and two brown bands. Surstylus of epandrium tapering and curved downward distally, curving up at tip. Gonocoxite wide and gonostylus short and small. Apical part of hypandrium with a pair of curved up and trough-shaped projections.

Wing length 8.0 mm. Wing (Fig. 5a) 3.2 times as long as wide, subhyaline, marked with two brown marks and two brown bands as follows: an oval brown mark at base of R, a triangular brown mark at base of Rs; median band extending from anterior margin of wing, covering base of R₂₊₃ and r-m, to middle section of CuA; subapical band extending from anterior margin of wing, covering tip of R₁ and R₂, to M₁₊₂ fork, slightly separated into two marks. Veins brown; Sc ending in C at level of basal third of R₂₊₃; Rs straight, 3 times the length of r-m.

Figure 5. 

Ptychoptera longwangshana Yang & Chen, 1998 and Ptychoptera gutianshana Yang & Chen, 1995 a wing of P. longwangshana b–f P. gutianshana (b wing c male genitalia, lateral view d epandrium, dorsal view e gonocoxite and gonostylus, dorsal view f hypandrium, ventral view). Scale bars: 1.0 mm (a, b); 0.2 mm (c–f).

China (Zhejiang).

Only one wing of the holotype was available during the study, while the rest of the holotype was not found in CAU. For a description and illustration of this species, also see Yang and Chen (1998).

Holotype male (CAU), China: Zhejiang Province, Kaihua District, Mount Gutianshan (350 m), 1993.IV.15, Hong Wu (light trap).

Wing marked with three brown marks and two brown bands. Surstylus of epandrium broadest at base, tapering and curved downward distally, forked at tip. Paramere with a pair of flaky projections and a vase-shaped projection. Gonostylus irregular rectangular with an elliptic basal projection on inner side with short hairs. Hypandrium trapeziform, anterior margin with a pair of C-shaped projections, middle area with a pair of digitiform projections, posterior margin with a pair of digitiform projections and a papillary projection.

Wing length 7.5 mm. Wing (Fig. 5b) 3.6 times as long as wide, subhyaline, marked with three brown marks and two brown bands as follows: three elliptic brown marks at base of Rs, at base of M and at midlength of CuA₁; median band extending from anterior margin of wing, covering base of R₂₊₃ and r-m, to the bend in distal section of CuA₂; subapical band extending from anterior margin of wing, covering tip of R₁, R₂ and fork of R₄₊₅, to fork of M₁₊₂. Veins brown; Sc ending in C at level of basal half of R₂₊₃; Rs straight, 3 times the length of r-m.

Male genitalia black. Epandrium (Fig. 5d) bilobed, each lobe strongly elongated and forming a long surstylus, surstylus broadest at base, tapering and curved downward distally, forked at tip, with brown hairs; proctiger with short hairs. Gonocoxite (Fig. 5e) short and swollen, 2 times as long as wide, basal apodeme three-eighths as long as gonocoxite; paramere with a pairs of flaky projections and a vase-shaped projection. Gonostylus (Fig. 5e) irregular rectangular with an elliptic basal projection on inner side with dense short hairs. Hypandrium (Fig. 5f) trapeziform, anterior margin with a pair of C-shaped projections, middle area with a pair of digitiform projections, posterior margin with a pair of digitiform projections and a papillary projection, papillary projection with dense short hairs.

China (Zhejiang).

Only two wings and male genitalia of the holotype were available during the study, while the paratype and the rest of the holotype were not found in CAU. For description and illustration of this species, also see Yang and Chen (1995).