Tipula (Vestiplex) dechangensis sp. nov.

Men, Qiu-Lei, Starkevich, Pavel & Saldaitis, Aidas, 2021, Two new crane fly species of the subgenus Vestiplex Bezzi, 1924 (Diptera, Tipulidae, Tipula) from Yunnan and Sichuan, China, with a key to species in the immota species group, ZooKeys 1040, pp. 33-48 : 33

Tipula (Vestiplex) dechangensis sp. nov. Figs 1-2 , 3-9 , 10-15 , 16-20 , 21 , 36

Type material.

Holotype: male, China, Sichuan, road Dechang/Miyi, 27°05.34'N, 102°01.40'E, alt. 2100 m, 10 May 2018, R. Butvila & A. Saldaitis (NRC); preserved in ethanol.

Paratypes: 3 males, 2 females, male genitalia slide No. PS0421m, wing slide No. PS0440m, female genitalia slide No. PS0422f, same data as holotype (NRC); preserved in ethanol.

Comparative material examined.

Tipula (V.) bicornuta Alexander, 1920: Holotype, male, China, Taiwan, Funkiko , 21 April 1917, pinned, T. Shiraki (USNM); antenna, wing and genitalia on slide (USNM). Tipula (V.) immota Alexander, 1935: Holotype, male, China, Sichuan, Kwanhsien, alt. 2000-4000 ft, 15-31 May 1933, Graham (USNM); pinned; paratype, male, topotypic (USNM), antenna, leg, wing and genitalia on slide (USNM) .

Diagnosis.

Tipula (V.) dechangensis sp. nov. can be recognized by the following combination of characters: body yellow, abdomen with basal segments yellow, tergites trivittate, distal segments, including hypopygium, dark brown; male antenna reaching base of abdomen if bent backward. Hypopygium with gonocoxite apically with a black spine that is curved at tip; tergite 9 divided at midline by a pale membrane, posterior margin with U-shaped notch, dorsal surface with pair of brown, inconspicuously protruded, rounded lobes, posterior margin terminating with a pair of black and short, wedge-shaped processes; adminiculum with a rounded preapical incision in lateral view. Female with cercus nearly straight, outer margin smooth, without visible serration, hypogynial valve in the shape of short brown plates, obtuse at apex.

Description

(Figs 1 - 20 ). Adult male (Fig. 1 ) (n = 4). Lengths: body 11.3-13.2 mm, wing 14.3-15.5 mm, antenna 5.1-6.6 mm.

Head. Yellowish, vertex and occiput yellowish with dark brown median line. Rostrum yellowish, with short nasus. Antenna 13-segmented, elongate, if bent backward reaching base of abdomen. Scape, pedicel and first flagellomere yellow; following flagellomeres basally brown, apically light brown. Each flagellomere except first slightly enlarged at base (Fig. 1 ). Apical flagellomere small, reduced. Verticils shorter than their corresponding segments. Palpus brownish-yellow.

Thorax. Pronotum light brown, with darker median line. Prescutum and presutural scutum brownish, with four brown longitudinal stripes. Interspaces grey, median pair fused anteriorly, with anterior margins inconspicuously bordered by darker brown. Scutum grey, scutal lobes each with two brown spots. Scutellum and mediotergite grey, with dark brown median line. Pleura yellowish, thinly grey-dusted (Fig. 1 ). Leg with coxa and trochanter yellow; femur yellow, with darkened tip; tibia and tarsal segments dark brown; tarsal claw with tooth (Fig. 1 ). Wing light brown (Fig. 2 ), cell sc not darker than ground colour, stigma dark brown, variegated by light areas including apical area of cell c and medial area of first cell of cell r1, a light band across apical area of cell r1, base of cells r3, r4 and r5, and median area of discal cell; remaining light area including base and apical areas of bm. Wing venation: R1 complete, R2+3+4 subequal in length to R3, R4 as long as Rs, R5 curved in apical half, r-m as long as base of R5, discal cell narrow, at least 3 times as long as petiole of cell m1, cell m1 more than 4 × longer than its petiole. Halter pale yellow, knob brown basally, pale yellow apically.

Abdomen. Abdominal segments 1-6 yellow, tergites trivittate, rest of segments, including hypopygium, brown (Fig. 1 ).

Hypopygium (Figs 3 - 15 ). Tergite 9 and sternite 9 totally separated. Tergite 9 completely divided at midline by a pale membrane (Fig. 5 ). Dorsal portion of tergite 9 laterally pale yellow, medially with a pair of brown, inconspicuously protruded, rounded lobes located on either side of midline; posterior margin covered with setae, medially with a U-shaped notch and a pair of black and short, wedge-shaped processes; posterolateral margin rounded (Figs 4 , 5 ). Ventral portion membranous, brown, each half triangular at margin (Fig. 5 ). Gonocoxite not fused with sternite 9, posterior part produced into a dorsally-directed spine (Figs 3 , 6 , 10 ). Lobe of gonostylus narrowed, slightly curved, finger-shaped (Fig. 7 ). Clasper of gonostylus yellow, terminating in an extended upper beak; dorsal crest nearly rectangular with short, blackened ridge generated from the dorsal corner; a suffused black rim along dorsal surface; lower beak absent; base with short lobe and covered with setae (Figs 3 , 6 , 8 ). Sternite 9 with ventral lobe of A9S dark brown, nearly triangular, covered with setae (Fig. 11 ). Dorsal lobe of A9S yellow, densely covered with setae, short, finger-shaped, fused with ventral lobe at base (Fig. 11 ). Adminiculum triangular in ventral view, basally flattened and dilated (Fig. 12 ); median portion, before apex, distinctly protruded with margin raised at base; with a rounded preapical incision in lateral view, apex narrowed (Fig. 13 ). Sperm pump with ejaculatory apodeme fan-shaped, with a small V-shaped notch medially (Fig. 14 ). Posterior immovable apodeme of same length as ejaculatory apodeme, with paired arms curved dorsally, terminating in an acute apex in lateral view (Fig. 15 ). Anterior immovable apodeme broad, flattened, obtuse in dorsal view. Aedeagus more than 3.5 times as long as sperm pump (Fig. 15 ).

Female. Adult (n = 2). Lengths: body 18.4-20.1 mm, wing 15.1-16.8 mm, antenna 2.9-3.1 mm.

Generally similar to male. Antenna yellow, if bent backward reaching presutural scutum. Flagellar segments, except first, slightly enlarged at base. Abdomen yellow, tergites trivittate, with distinct dorsal stripe.

Ovipositor (Figs 16-20 ). Tergite 10 shiny yellow. Cercus yellow, nearly straight, with tip obtuse and outer margin smooth (Fig. 16 ). Sternite 8 yellow, with hypogynial valve brown (Figs 16 , 17 ).

Hypogynial valve in the shape of short plate, brown (Fig. 17 ). Posterior margin of hypogynial valve medially incised, terminating in an obtuse apex in ventral view. Posterior part of sternite 9 covered with short filaments, shovel-shaped, medially with a groove, posterior margin rounded (Fig. 18 ). Anterior part of sternite 9 narrow, nearly straight (Fig. 18 ). Furca long, posteriorly flattened, anteriorly narrow (Fig. 19 ). Three spermathecae, spherical (Fig. 20 ).

Biology and distribution.

The new species is known from the Dechang, located at the eastern edge of the Tibetan plateau in Sichuan Province, China (Fig. 36 ). Two males and three females were collected at ultraviolet light at the beginning of May, at an altitude of around 2100 m. The new species was collected in the dry valley of a small river, with slopes covered by mixed forest dominated by various broad-leaved trees such as oaks ( Quercus dentata Thunberg, Q. glauca Thunberg), poplars ( Populus cathayana Rehder, P. simonii Carrière), elm ( Ulmus parvifolia Jacquin), rhododendrons ( Rhododendron brachycarpum G. Don, R. dauricum Linnaeus), and bamboos ( Phyllostachys ssp., Borinda ssp., Fargesia spp.) (Fig. 21 ).

Etymology.

The new species name is derived from the type locality, Dechang, in Sichuan, China.

Disscussion.

Tipula (V.) dechangensis sp. nov. is most similar to T. (V.) gongdangensis sp. nov. in body and antenna colouration, and in the shape of the gonocoxite, the clasper of the gonostylus and the dorsal lobe of A9S. These two species can be separated by following details of tergite 9: posterior margin with U-shaped notch, black processes wedge-shaped, and posterolateral corner without extension in T. (V.) dechangensis sp. nov.; posterior margin broadly emarginated, without U-shaped notch, black processes nearly triangular, and posterolateral corner extended in T. (V.) gongdangensis sp. nov. Both species can be also separated by differences in the adminiculum, which has a preapical incision in T. (V.) dechangensis sp. nov. that is absent in T. (V.) gongdangensis sp. nov., and by the ventral lobe of A9S, which is well developed in T. (V.) dechangensis sp. nov. and indistinct in T. (V.) gongdangensis sp. nov.

Figures

Figure 21. Type locality of Tipula (Vestiplex) dechangensis sp. nov. China, Sichuan, road Dechang / Miyi, alt. 2100 m.

Figure 36. Collecting sites of Tipula (Vestiplex) in China: Sichuan, Tipula (V.) dechangensis sp. nov. (triangle); Yunnan, Tipula (V.) gongdangensis sp. nov. (circle).

Figures 1, 2. Tipula (Vestiplex) dechangensis sp. nov. 1 holotype male, lateral view 2 wing. Scale bar: 2.0 mm.

Figures 3 - 9. Male terminalia of Tipula (Vestiplex) dechangensis sp. nov., holotype 3 hypopygium, lateral view 4 tergite 9, caudal view 5 tergite 9, dorsal view 6 hypopygium, caudal view 7 lobe of gonostylus (left) 8 clasper of gonostylus (left), lateral view 9 hypopygium, caudal view. Scale bars: 0.5 mm (10 - 13); 1.0 mm (14, 15).

Figures 10 - 15. Male terminalia of Tipula (Vestiplex) dechangensis sp. nov., holotype 10 right gonocoxite, lateral view 11 lobes of appendage of sternite 9 12 adminiculum, lateral view 13 adminiculum, ventral view 14 sperm pump, dorsal view 15 sperm pump, lateral view.

Figures 16 - 20. Female terminalia of Tipula (Vestiplex) dechangensis sp. nov. (paratype) 16 ovipositor, left lateral view 17 eighth sternite with hypogynial valves, ventral view 18 sternite 9 with bursa 19 furca 20 spermatheca with spermathecal duct. Scale bars: 1.0 mm (16, 17); 0.5 mm (18 - 20).