Tipula (Vestiplex) maoershanensis Men & Young

Men, Qiu-Lei, Young, Chen W., Starkevich, Pavel, Yu, Yong-Fu & Lei, Xiao-Ping, 2017, Two new species of Tipula (Vestiplex) from Southern China based on morphological and molecular data, with redescription of Tipula (Vestiplex) bicalcarata (Diptera, Tipulidae, Tipulinae), ZooKeys 658, pp. 63-80 : 68-71

Tipula (Vestiplex) maoershanensis Men & Young sp. n.

Diagnosis.

Whole body generally brownish in coloration (Figs 26-29). Prescutum with median stripe brighter than lateral stripes (Fig. 27). Hypopygium dark brown (Fig. 30). Gonocoxite produced into a long arm, basally broad and gradually narrowed to the apex (Figs 30-31).

Description.

Male. Length: Body: 12.0-12.3 mm (excluding antenna, n = 2); Wing: 16.2-16.5 mm (n = 2); Antenna: 3.5-3.7 mm (n = 2).

Head. Rostrum light brown with brownish nasus (Fig. 26). Antenna 13-segmented, bent backward extending to root of wing; scape reddish brown, cylindrical, expanded apically; pedicel reddish-brown, short; flagellum brown, flagellomere subequal in length, basal enlargement black with abundant black verticils, longest ones subequal to length of corresponding flagellomeres. Palpi entirely reddish brown. Vertex without marking (Fig. 28).

Thorax. Generally brown except as noted. Pronotum brown, changed to black medially. Prescutum with three brown stripes, median one darker than laterals (Fig. 27). Scutum with two dark brown markings (Fig. 27). Scutellum with dark median stripe. Postnotum wholly brown. Pleura entirely reddish-brown (Fig. 26). Legs slender, coxae and trochanters brown, femora brown with tip black, tibiae brown with tip black, tarsi black. Halteres with stem brown, knob darker. Wings reddish-brown, cells c and sc darker than ground color; stigma dark brown; Rs suffused with dark brown at origin point; discal cell transparent; several large hyaline areas at cells r, m and a (Fig. 29). Venation: R1+2 entire, discal cell narrow, elongated, petiole of cell m1 distinctly shorter than discal cell (Fig. 29).

Abdomen. Abdominal tergites reddish-brown with brown lateral stripes, sternites entirely reddish brown. Hypopygium dark brown (Fig. 30). Tergite nine entirely divided into two parts, produced into horn-shaped process in the lateral angle, ventral side of tergite nine with a pair of ear-shaped processes (Figs 32, 34). Gonocoxite extended into long arm, directed caudally, widened at base and narrowed to apex; ventrally, with central band of long black setae (Figs 30-31, 33). Outer gonostylus elongated, thin, generally curled as a tube (Fig. 35). Inner gonostylus produced into black beak, with a finger-shaped, rounded, expanded apically process on dorsal side.

Sperm pump. with compressor apodeme fan-shaped, shallowly emarginated in middle, deeper coloration in median region, suffused by several dark stripes, forming a 65° angle with posterior immovable apodeme (Fig. 37). Posterior immovable apodeme distinctly shorter than compressor apodeme, gradually narrowed to apex (Fig. 36). Anterior immovable apodeme short, gradually narrowed to apex (Fig. 36). Aedeagus tubular, almost 2.5 times longer than sperm pump, acute apically (Fig. 36).

Type material.

Holotype male. CHINA: Guangxi Zhuang Autonomous Region, Maoershan Mountain, 25°48'N, 110°25'E, 21 May 2015, Guoxi Xue leg. Paratype. 1 male, same data as holotype.

Distribution.

China (Maoershan Mountain, Guangxi Zhuang Autonomous Region, Fig. 40).

Remarks.

The new species is placed in subgenus Tipula (Vestiplex) because of its male hypopygium with elongated gonocoxite, which is also supported by the molecular analysis (Fig. 39). The new species is similar to Tipula (Vestiplex) coxitalis Alexander, 1935, in the body color and the structure of gonostylus, it can be easily distinguished from the latter by the gonocoxite not expanded distally (distal end of gonocoxite expanded in Tipula (Vestiplex) coxitalis figs 30, 31 in Alexander, 1935b), by the sternite without a band of long setae on each lateral sides (with such long hair in Tipula (Vestiplex) coxitalis fig. 30 in Alexander, 1935b), by the inner gonostylus with dorsal process distinctly larger than that of Tipula (Vestiplex) coxitalis . Pairwise genetic distance between Tipula (Vestiplex) maoershanensis sp. n. and Tipula (Vestiplex) coxitalis is 0.048 based on the Kimura-2-parameter model, suggesting distinct genetic variation between these two species. Six lower values of pairwise genetic distance were observed in comparisons to known species (Table 2), which could be taken as indirect evidence. The new species is also similar to Tipula (Vestiplex) bicalcarata by the body color and the structure of gonocoxite. It can be easily distinguished from the latter by the tergite nine produced into a horn-like process in lateral angle (the tergite nine produced into an ear-shaped process in Tipula (Vestiplex) bicalcarata , Fig. 8), the dorsal angle of inner gonostylus rounded and expanded apically (the dorsal angle of inner gonostylus gradually narrowed to apex in Tipula (Vestiplex) bicalcarata , Fig. 11). Pairwise genetic distance between these two species is 0.028 based on the Kimura-2-parameter model. Although the value is relatively low, it is equal to the comparison value of Tipula (Pterelachisus) wahlgreni and Tipula (Pterelachisus) mutila , while higher than the comparison value of Tipula (Pterelachisus) pseudovariipennis and Tipula (Pterelachisus) varipennis (0.019).

Etymology.

The specific epithet is a noun ‘maoershan’ with Latin suffix ‘ensis’, referring to the distribution of the new species.