Cerodontha (Cerodontha) flavicornis (Egger, 1862)

Figs 2 A – N, 3 A – L

Ceratomyza flavicornis Egger, 1862: 782; Schiner 1864: 311.

Cerodontha flavicornis: Hendel 1920: 169; Hering 1927: 160; Stackelberg 1933: 465.

Cerodontha (Cerodontha) flavicornis: Nowakowski 1967: 656; 1972: 738; 1973: 51; Rohdendorf 1970: 270; Zlobin 1979: 874; Soós and Papp 1984: 286; Spasić 1996: 114; Černý 2018: 125; Černý and Bächli 2018: 134.

Specimens examined.

China, Qinghai Province: • 4 ♂♂ 15 ♀♀ (IMAU), Delingha City, entrance of Cypress Mountain Forest Park, 3296 m, 37°26'58.01"N, 97°20'13.54"E, 09. VIII. 2021, leg. Li Shi ; • 3 ♀♀ (IMAU), Haidong City, Huzhu County, Bazha Town, Baimuxia Village, 3070 m, 37°00'09.38"N, 102°07'36.04"E, 24. VII. 2021, leg. Li Shi ; • 2 ♂♂ 20 ♀♀ (IMAU), Tianjun County, grassland near Guanjiaoshan Highway, 3626.6 m, 37°9'32.09"N, 98°51'34.81"E, 08. VIII. 2021, leg. Li Shi ; • 2 ♀♀ (IMAU), Menyuan County, Xianmi Town, Meihua Village, 3148 m, 37°17'12.17"N, 102°08'45.34"E, 30. VII. 2021, leg. Li Shi ; • 8 ♂♂ 7 ♀♀ (IMAU), Menyuan County, Xianmi Town, Qiaotan Village, Qihankaigou, 2715 m, 37°09'33.51"N, 102°02'05.13"E, 30. VII. 2021, leg. Li Shi ; • 10 ♂♂ 5 ♀♀ (IMAU), Menyuan County, Zhugu Town, Dezong Village, 2894 m, 37°13'02.69"N, 102°11'58.20"E, 26. VII. 2021, leg. Li Shi ; • 38 ♂♂ 63 ♀♀ (IMAU), Menyuan County, Zhugu Town, Sigou, 2616 m, 37°07'56.19"N, 102°24'03.91"E, 24. VII. 2021, leg. Li Shi ; • 8 ♂♂ 12 ♀♀ (IMAU), Qilian County, Zhamashi Town, Xigou, 3196 m, 38°08'32.91"N, 99°58'12.59"E, 03. VIII. 2021, leg. Li Shi ; • 6 ♂♂ 14 ♀♀ (IMAU), Qilian County, Yeniugou Town, Yanglong Town, near Xiage’er Snow Mountains, 3313.3 m, 38°48'30.32"N, 98°23'48.35"E, 04. VIII. 2021, leg. Li Shi ; • 5 ♂♂ 17 ♀♀ (IMAU), Qilian County, Babao Town, Binggou Village, Xiaxigou, 3170 m, 38°07'50.17"N, 100°09'57.18"E, 05. VIII. 2021, leg. Li Shi ; • 3 ♂♂ 1 ♀♀ (IMAU), Qilian County, Zhamashi Town, Donggou, 3106 m, 38°09'10.99"N, 100°01'26.85"E, 03. VIII. 2021, leg. Li Shi ; • 27 ♂♂ 27 ♀♀ (IMAU), Qilian County, Lujiaogou, 3417 m, 38°06'31.22"N, 100°28'42.33"E, 01. VIII. 2021, leg. Li Shi . DNA sequence number PX 103170 from GenBank.

Diagnosis.

Frons with three ori inclinate and two ors reclinate surrounded by faint brown at base. Antenna with yellow scape and pedicel, first flagellomere mostly brown with anterodistal corner like a short spine. Mesonotum mostly black except for rectangular part yellow above notopleuron, postpronotum black on anterior half and yellow on posterior half; 1 + 2 dc. Legs mostly black except for fore coxae yellow at apex and all femora yellow on apical 5 / 6. Distiphallus gourd-shaped with enlarged apex and complete ventral opening.

Redescription.

Male (Fig. 2 A – N). Body length 2.3–3.0 mm; wing length 2.7–3.2 mm. Female (Fig. 3 A – L). Body length 2.5–3.6 mm; wing length 2.8–3.4 mm.

Head (Fig. 2 B, C) light yellow. Frons wider than high, conspicuously projecting above eye in lateral view, ~ 1.1 × width of eye in dorsal view; three ori inclinate and two ors reclinate surrounded by faint brown coloration at base; orbital setulae slender in one inclinate row near ori; inner vertical setae surrounded by yellowish brown coloration at base; outer vertical setae on black background. Ocellar triangle dark brown, ocellar setae longer distinctly than ors. Lunule 2.3 × wider than high and upper margin brown near level of posterior ori. Antenna mostly yellow, first flagellomere mostly brown with anterodistal corner like a short spine, arista brown with microscopic pubescence. Gena ~ 2 / 5 height of eye. Clypeus and palpus light yellow.

Thorax (Fig. 2 D, E) mostly black. Mesonotum mostly black except for rectangular part yellow above notopleuron, postpronotum black on anterior half and yellow on posterior half; 1 + 2 dc; acr in 2–4 irregular rows, one postsutural intra-alar seta, one presutural and two postsutural supra-alar setae. Notopleuron yellow. Anepisternum black except dorsal and posterior margin yellow, with one strong anepisternal seta, four long setulae and two short setulae. Katepisternum black with one strong katepisternal seta and six short setulae. Scutellum yellow but dark brown at lateral corner. Legs mostly black, fore coxae yellow at apex and all femora yellow on apical 5 / 6. Wing: Costa with 2 nd (between R 1 and R 2 + 3), 3 rd (between R 2 + 3 and R 4 + 5) and 4 th (between R 4 + 5 and M 1) sections in proportion of 4.4: 1.3: 1; ultimate and penultimate sections of M 1 in proportion of 2.3: 1; ultimate and penultimate sections of M 4 in proportion of 1.3: 1; r-m at apical 1 / 3 of discal cell. Calypter yellow with margin and fringe dark brown. Halter pale yellow.

Abdomen (Fig. 2 G) mostly yellow with wide black stripes in the middle, tergite 6 entirely black. Male genitalia (Fig. 2 H – N): epandrium rounded with strong dorsal and lateral setae; surstylus with sparse and short spines; mesophallus twice length of distiphallus, with ventral opening at distal 1 / 4; distiphallus gourd-shaped with enlarged apex and complete ventral opening; ejaculatory apodeme asymmetrical, blade clear and broad; sperm pump with conspicuously brown bottom connected with base of duct. Cercus lightly sclerotized.

Female. Tergite 6–7 entirely black. Other external characteristics (Fig. 3 A – G) same as the male except for the female terminalia. Terminalia (Fig. 3 H – L): two spermathecae equal in size, circular and truncated at basal 1 / 6; duct long, with helical texture and a short hyaline segment near base of spermathecae; ventral receptacle (Fig. 3 L) circular in lateral view, and butterfly-shaped in ventral view; proctiger constricted on apical 1 / 3 (Fig. 3 K). Cercus setose, relatively long and well-sclerotized.

Distribution.

Palaearctic: Albania, Andorra, Austria, Belgium, China (Qinghai) #, Croatia (Černý 2018), France, Germany, Hungary, Italy, Montenegro (Spasić 1996), Poland, Russia, Spain, Switzerland (Černý and Bächli 2018).

Remarks.

Among the Palaearctic species of subgenus Cerodontha, this species is distinctly characterized by its antennal shape and coloration, the black mesonotum, the stripes on the abdominal tergites, and the distinctive shape of the distiphallus. The species is similar to C. (C.) affinis (Fallén, 1823) from the Palaearctic region in the following characters: mesonotum black; notopleuron, apical half of postpronotum, dorsal margin of anepisternum and the middle of scutellum yellow; acr in two rows; calypter yellow with margin and fringe dark brown; femora of yellow. But it can be differentiated from the latter by the first flagellomere being yellowish with a spine at upper corner; mesonotum having 1 + 2 dc; legs having black tibiae and tarsi; abdomen being mostly yellow with wide black stripes in the middle, and the tergite 6 being entirely black. In C. (C.) affinis, the first flagellomere is black with blunt projection at dorsal corner (Spencer 1976: fig. 316); the mesonotum has 1 + 3 dc; the fore tibiae are yellowish brown; the abdomen is shining black but all tergites yellow-bordered and also laterally yellow in male.