﻿Three new fold-winged crane flies of the genus Ptychoptera Meigen, 1803 (Diptera, Ptychopteridae) from southern China

﻿Abstract Three new Ptychoptera Meigen, 1803 species from southern China, P.hekouensissp. nov., P.longasp. nov., and P.xiaohuangshanasp. nov., are described and illustrated. These new species are mainly distinguished from congeners by their body colors and male genitalia. The genus Ptychoptera is recorded from Guangdong, China for the first time. An updated key to all Chinese Ptychoptera species is provided.


Introduction
The family Ptychopteridae, also known as fold-winged crane flies, is a group of slender tipulid-like flies in the lower Diptera. Ptychopteridae are divided into subfamilies Bittacomorphinae and Ptychopterinae. The genus Ptychoptera Meigen, 1803 is the only extant genus in subfamily Ptychopterinae and can be easily distinguished by the antennae in adults with 13 flagellomeres, the wing with M 1+2 forked, and the gonopod with a simple gonocoxite (Alexander 1981;Rozkošný 1997;Nakamura and Saigusa 2009). 9 Sixth and 7 th sterna yellow, tip of surstylus curved up when viewed from the lateral side, retrose basal projection on inner side with tip bilobate, paramere with a pair of hook-shaped projections and a pair of conical projections, subapical sclerite of aedeagus serrated with five teeth ..  Diagnosis. Scutellum mostly brownish black, middle area yellow; wing marked with small brown marks at base of Rs, tip of R 1 , base of R 2+3 , fork of R 4+5 , r-m, and fork of M 1+2 ; epandrial clasper tapering and slightly curved distally to the middle, inner side with two papillary projections; medial lobe of basal lobe of gonostylus ear-shaped. Description. Male. Body length 8.0 mm, wing length 9.0 mm. Vertex and frons black; face and clypeus yellow with brown hairs; gena yellow with a black elliptical spot medially, hairs on gena dark brown; occiput yellow. Compound eyes black without pubescence. Scape, pedicel and basal 1/2 of 1 st flagellomere yellow, remaining flagellomeres dark brown; hairs dark brown. Proboscis yellow with brown hairs. Palpus yellow with last segment gradually darked apically, hairs brown. Thorax ( Fig. 1a, b). Pronotum and propleuron yellow. Prescutum mostly brownish black, anterior margin with lateral area yellow; scutum and paratergite mostly brownish black, posterior margin yellow; scutellum mostly brownish black, middle area yellow with a patch of dense brown hairs; postnotum yellow. Mesopleuron uniformly yellow. Coxae and trochanters yellow. Wing (Fig. 2a) 3.3 times as long as wide, subhyaline, apical 1/2 slightly brown, marked with small brown marks at base of Rs, tip of R 1 , base of R 2+3 , fork of R 4+5 , r-m, and fork of M 1+2 . Veins brown; Sc ending in C exceeding basal 1/3 of R 2+3 ; Rs straight, 4 times the length of r-m; r-m arise from Rs. Wing with setae below fold in cell cua 2 , and over tip 1/3 of wing. Halter and prehaltere pale yellow with brown hairs.
Female Remarks. This new species is similar to P. wangae from China but can be separated from the latter by the scutellum mostly brownish black with middle area yellow, the 2 nd tergum mostly brownish black with middle area yellow, the epandrial clasper with two papillary projections on inner side, and the medial lobe of basal lobe of gonostylus ear-shaped. In P. wangae, the scutellum is uniformly yellow brown, the 2 nd tergum is mostly yellow with posterior margin brown, the epandrial clasper does not have papillary projection on inner side, and the medial lobe of basal lobe of gonostylus is semicircular (Kang et al. 2013). Diagnosis. Mesopleuron mostly brown, except upper 1/2 of anepisternum yellow; wing marked with four brown marks and one brown band; epandrium not bilobed, epandrial lobe rectangle; epandrial clasper finger-shaped, merged basally, basal 1/2 broad and rectangle, apical 1/2 narrowing bilaterally; secondary lobe of apical stylus of gonostylus sickle-shaped; terminal division of hypandrium elliptic.
Description. Male. Body length 7.5 mm, wing length 7.5 mm. Vertex and frons brown; face and clypeus yellow with brown hairs; gena yellow with a black elliptical spot medially, hairs on gena brown; occiput yellow. Compound eyes black without pubescence. Scape and pedicel yellow, flagellomeres light yellow; hairs on antenna brown. Proboscis yellow with brown hairs. Palpus yellow with brown hairs.   Thorax (Fig. 1c, d). Pronotum light brown; propleuron yellow. Prescutum, scutum and paratergite uniformly brown; scutellum mostly brown, middle area yellowish brown; postnotum brown, laterotergite with a patch of dense brown hairs. Mesopleuron mostly brown, except upper ½ of anepisternum yellow. Coxae and trochanters yellow. Wing (Fig. 2b) 3.8 times as long as wide, subhyaline, marked with four brown marks and one brown band as follows: four elliptic brown marks at base of cell R, tip of R 1 , fork of R 4+5 , and fork of M 1+2 ; one brown band extending from anterior margin of wing, covering base of R 2+3 and r-m, to the bend in distal section of CuA 2 . Veins brown; Sc ending in C at level of basal 1/3 of R 2+3 ; Rs straight, 2 times the length of r-m; r-m arise from R 4+5 . Wing with setae over Sc and Rs, at and below fold in cell cua 2 , and over tip 1/2 of wing (sparse before forks of R 4+5 and M 1+2 ). Halter and prehaltere pale yellow with light brown hairs.
Remarks. This new species is similar to P. yankovskiana from China and Korea but can be separated from the latter by first tergum brown with basal 1/3 yellow, the epandrium not bilobed, and the epandrial claspers merged basally. In P. yankovskiana, the first tergum is uniformly dark brown, the epandrium is bilobed and the epandrial claspers is not merged basally (Kang et al. 2019).
Description. Male. Body length 7.0 mm, wing length 7.0 mm. Vertex and frons brown; face and clypeus yellow with light brown hairs; gena yellow with a black elliptical spot medially, hairs on gena brown; occiput yellow. Compound eyes black without pubescence. Scape and pedicel yellow, flagellomeres light yellow; hairs on antenna brown. Proboscis light yellow with light yellow hairs. Palpus light yellow with light yellow hairs.
Thorax (Fig. 1e, f ). Pronotum and propleuron light brown. Prescutum, scutum, and paratergite uniformly brown; scutellum mostly brown, middle area yellowish brown; postnotum brown, laterotergite with a patch of dense brown hairs. Mesopleuron mostly brown, except upper ½ of anepisternum yellow. Coxae and trochanters yellow; femora yellow with brown ring apically; hairs on legs brown. Wing (Fig. 2c) 3.8 times as long as wide, subhyaline, marked with three brown marks and two brown bands as follows: one triangular brown mark at base of M, two elliptic brown marks at base of Rs and at midlength of CuA 1 ; median band extending from anterior margin of wing, covering base of R 2+3 and r-m, to the bend in distal section of CuA 2 ; subapical band extending from anterior margin of wing, covering tip of R 1 , R 2 , and fork of R 4+5 , to fork of M 1+2 .Veins brown; Sc ending in C not at level of basal third of R 2+3 ; Rs slightly curved medially, 4.1 times the length of r-m; r-m arise from Rs. Wing with setae over Sc and Rs, at and below fold in cell cua 2 , and over tip 1/2 of wing (slightly sparse before forks of R 4+5 and M 1+2 ). Halter and prehaltere pale yellow with light brown hairs.
Remarks. This new species is similar to P. bellula from China but can be separated from the latter by the 2 nd tergum light brown with middle 1/3 yellow, the epandrial clasper with a curved finger-shaped projection interiorly, the epiproct with two papillary projections posteriorly, and the medial lobe of basal lobe of gonostylus toothbrush-shaped. In P. bellula, the 2 nd tergum is black with base yellow, the epandrial clasper does not have a curved finger-shaped projection interiorly, the epiproct have a strongly haired papillary projection posteriorly, and the medial lobe of basal lobe of gonostylus is semilunar (Alexander 1937;Krzeminski and Zwick 1993).