Diostracus (Diostracus) campsicnemoides, Grichanov, I. Ya., 2015

Grichanov, I. Ya., 2015, A New Species Of Diostracus Loew (Diptera: Dolichopodidae) From The Yunnan Province Of China, Far Eastern Entomologist 300, pp. 12-16 : 13-15

Diostracus (Diostracus) campsicnemoides sp. n.

Figs 1–5

MATERIAL. Holotype. Male , China: Yunnan, mountains between Shangri-La and Habaxue Shan, E slope, NW Bengla, 27°37’53”N, 99°57’50”E, 3570 m, fir forest, 25.V 2015, leg. G. Davidian [ ZIN].

DIAGNOSIS. According to Grichanov (2013), the new species belongs to the nominotypical subgenus Diostracus Loew, 1861 , differing from other subgenera in the presence of several dorsal setae on antennal scape. Following the key to Chinese species ( Yang et al., 2011), the new species is close to D. nishiyamai Saigusa, 1995 , which has glabrous scape, mostly black tibiae and tarsi, short cercus, etc. Following the key to Himalayan and Tibetan species ( Wang et al., 2015), the new species keys to D. (Diostracus) tangalensis Saigusa, 1984 , which has also setose antennal scape, but differing from D. (D.) campsicnemoides in blackish legs, short setose four leg, short fore basitarsus, and small triangular cercus.

DESCRIPTION. Male. Head ( Fig. 1 ): black, pollinose; clypeus 1/5 as wide as head, slightly wider than high; face nearly half as wide as clypeus, not wider than height of postpedicel; ocellar bristles strong, vertical and postvertical bristles about 1/2 as long as ocellar bristle; postocular ciliation black, strong, nearly as long as postvertical on upper 1/2, finer and yellowish below; ventral 1/2 of postcranium clothed with many long dirty yellow hairs, some of which as thick as vertical bristle; antenna black, with setose vase-like scape; pedicel with ring of short setae; postpedicel nearly 2 times as long as high, subtriangular, rounded distally, with short hairs, with middorsal simple arista-like stylus; basal segment of stylus thickened; length (mm) of scape to pedicel to postpedicel to stylus (1st and 2nd segments), 42/22/48/13/215; palpus ovate, 1.6 times as long as wide, 1/5 as long as eye height, slightly dilated at middle; palpus dark yellow, pollinose, bearing black hairs and one seta; proboscis moderately large, brown.

Thorax: violet-black, with washed pollinosity; mesonotum with pair of blackish longitudinal stripes; acrostichals absent; 5 pairs of dorsocentrals; 1 humeral with 1-2 short setae in front, 1 posthumeral, 2 notopleurals, 1 sutural, 1 postsutural, 1 supra-alar, 1 postalar; scutellum with 1 pair of strong scutellars; proepisternum with about 3 yellow setae on its lower portion; scutellum about 3 times wider than long; postscutellum about 3 times as long as scutellum.

Legs: rather long, mostly yellow; tibiae brown at distal apex; tarsi brown-black from apex of basitarsus; fore coxa on anterior surface clothed with short black setae, stronger and denser on distal half; fore femur ( Fig. 2 ) simple, moderately thick in basal half, with ventral row of 5-7 erect bristles, longer than diameter of femur; fore tibia slightly thickened, narrowed at apices, bearing 3-4 short dorsal bristles, anteroventral row of 7-8 strong bristles, posteroventral row of elongate hairs, denser at distal apex; fore basitarsus long, with ventral and dorsal rows of numerous setae, longer than diameter of basitarsus; 2nd to 5th tarsomeres simple, bearing simple setulae; 5th segment slightly flattened dorsoventrally; pulvilli not reduced, but small, empodium well developed and ventrally ciliated, claws small, about one third as long as 5th segment; mid coxa bearing some apical black setae; mid femur simple, with ventral row of 3-4 with short anterior

bristles at middle, longer than diameter of femur, Diostracus ) campsicnemoides sp. n. hypopygium, left lateral view.

preapical seta; mid tibia straight, with 2-3 anterodorsal bristles and few short ventral and posterior setae; mid tarsus slender, simple and short setose, with small claws, pulvilli and empodium; hind coxa bearing short black seta at apex; hind femur long and simple, with short anterior preapical bristle; hind tibia slender, bearing short setae on anterodorsal, posterodorsal and ventral surfaces; hind basitarsus with strong posteroventral seta at base; next tarsomeres slender and simple; claws, pulvilli and empodium small. Fore podomere length (from femur to tarsomere 5, mm): 1.28/1.35/0.91/0.63/0.34/0.23/0.19, mid leg: 1.65/ 2.00/1.17/0.59/0.32/0.21/0.19, hind leg: 1.98/2.49/1.03/0.60/0.36/0.25/0.21.

Wing ( Fig. 3 ): simple, almost hyaline, with simple veins; Sc developed; R 2+3 and R 4+5 weakly convex anteriorly; R 4+5 and M 1+2 almost parallel behind level of dm-cu; M 1+2 distinctly convex anteriorly; ratio of part of costa between R 2+3 and R 4+5 to this between R 4+5 and M 1+2, 50/40; ratio of cross-vein dm-cu to distal part of CuA 1, 40/31; dm-cu almost perpendicular to longitudinal wing axis; calypter yellow, with white cilia; halter yellow.

Abdomen ( Fig. 4 ): black, with washed pollinosity, with short black setae; 1st tergum with yellow hairs and ciliated with black bristles at posterior margin; 2nd tergum normal; 2nd and 3rd sterna with microscopic hairs; 3rd and 5th terga narrowed on dorsal side; 4th tergum strongly swollen, as long as 1st–3rd terga combined; 4th sternum large, subquadrate, with 2 lateral groups of short erect setae, with posterior projection; 5th tergum with 2 ventral groups of short erect setae; 5th sternum reduced to pair of small plates covered with short setae; 6th tergum small, hardly visible, shortly setose; 7th tergum reduced to semicircular arc, with some short setae; 8th segment large, with few pale hairs; hypopygium ( Figs. 4 , 5 ) black, moderately large, with mostly dark yellow appendages; hypandrium elongated and bifurcated from base, expanded distally at apex; phallus simple; epandrial lobe broad, with pointed process and setose as figured; surstylus brown, glabrous; dorsal and vental lobes of surstylus fused at base; dorsal lobe of surstylus small, oval; vental lobe of surstylus strongly enlarged, with 2 leaf-like arms; cercus yellow basally, black in distal half; cercus twice longer than epandrium, filiform, with long sparse yellow setae.

Female: unknown.

MEASUREMENTS. Body length without antennae 3.7 mm, antenna length 1.0 mm, wing length 4.7 mm, wing width 1.5 mm.

DISTRIBUTION. China (Yunnan).

ETYMOLOGY. The species is named for his similarity with species of the genus Campsicnemus Haliday, 1851 .

Figures

Figs. 1–4. Diostracus (Diostracus) campsicnemoides sp. n. 1 – head, lateral view; 2 – fore leg, with inset showing tarsomeres 2-5 of fore tarsus; 3 – wing; 4 – abdominal segments 4-8 and hypopygium, left lateral view.

Fig. 5. Diostracus (