Homoneura (Homoneura) biconica Chen & Li, 2024

Chen, Xulong, You, Pengyan, Li, Wenliang & Zhang, Zhisheng, 2024, Seven new species of the subgenus Homoneura Malloch (Diptera, Lauxaniidae, Homoneura) from Jiangjin District, southwestern Chongqing, China, ZooKeys 1206, pp. 45-80 : 45-80

Homoneura (Homoneura) biconica Chen & Li sp. nov.

Figs 1–5 , 6–10 Chinese name: 双锥同脉缟蝇

Type material.

Holotype: ♂, China, Chongqing City, Jiangjin District, Simianshan Natural Reserve , Zhengqiangou , 28 ° 36 ' 59.54 " N, 106 ° 26 ' 25.88 " E, 1273 m, 14. VI. 2022, leg. Xulong Chen. Paratypes: 6 ♂♂, same data as holotype; 1 ♂, China, Chongqing City, Jiangjin District, Simianshan Natural Reserve, Dahonghai, 28 ° 35 ' 34.27 " N, 106 ° 26 ' 34.93 " E, 1144 m, 15. VII. 2022, leg. Xulong Chen.

Etymology.

The specific name comes from the combination of the prefix bi - (meaning two) and the Latin word, conica (meaning cone-shaped), referring to the surstylus consisting of two subuliform processes in lateral view.

Diagnosis.

Mesonotum with acrostichal setulae in ten irregular rows. Basal margin of brown apical spot on R 2 + 3 behind vertical level as crossvein dm-cu; brown apical spots on R 2 + 3, R 4 + 5, and M 1 slightly confluent; subcostal cell hyaline. Male tergites 2–5 with blackish brown posterior margin. Surstylus consisting of two subuliform processes in lateral view. Pregonite and postgonite inwardly curved, pregonite with one long setula. Phallus long and knife-like with an acute subapical tooth in lateral view.

Description.

Male. Body length 8.4–8.6 mm, wing length 8.3–8.4 mm.

Head (Fig. 1 ) yellow. Frons as long as wide and parallel-sided; ocellar triangle yellow, ocellar seta developed, longer than anterior fronto-orbital seta, anterior fronto-orbital seta shorter than posterior fronto-orbital seta. Gena ~ 1 / 7 height of eye. Antenna yellow, first flagellomere ~ 2.0 × longer than high; arista black except pale brown at base, long plumose, with longest ray as long as height of first flagellomere. Proboscis and palpus yellow.

Thorax (Fig. 4 ) yellow, with gray pruinosity. 0 + 3 dorsocentral setae, anteriormost postsutural dorsocentral seta far from scutal suture, acrostichal setulae in ten irregular rows. Legs yellow. Fore femur with eight posterior dorsal setae, five posterior ventral setae and ctenidium with 16 short setae; fore tibia with one dorsal preapical seta and one short apical ventral seta. Mid femur with five or six anterior setae and one apical posterior seta; mid tibia with one dorsal preapical seta and three strong apical ventral setae. Hind femur with several weak anterior ventral setae and one preapical anterior dorsal seta; hind tibia with one weak dorsal preapical seta and one short apical ventral seta. Wing (Fig. 2 ) slightly yellow, basal margin of brown apical spot on R 2 + 3 behind vertical level as crossvein dm-cu; brown apical spots on R 2 + 3, R 4 + 5, and M 1 slightly confluent and forming pale brown connecting area between apical spots on R 2 + 3, R 4 + 5, and M 1; brown median spot on R 4 + 5 separated from brown cloud-like spot on crossvein dm-cu; subcostal cell hyaline; eight short hairs present at base of R 4 + 5; 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: 1: 0.8; r-m before middle of discal cell; ultimate and penultimate sections of M 1 in proportion of 3.5: 3.3; ultimate section of CuA 1 ~ 1 / 8 of penultimate. Haltere yellow.

Abdomen (Fig. 5 ) yellow, tergites 2–5 with blackish brown posterior margin. Male genitalia (Figs 6–10 ): syntergosternite circular, with a triangular ventral process and with several dorsal setulae. Epandrium broad in lateral view; surstylus consisting of a longer subuliform process and a shorter subuliform process in lateral view. Hypandrium H-shaped. Pregonite and postgonite curved inwards, pregonite with one long setula. Phallus long, knife-like, and with an acute subapical tooth in lateral view. Phallapodeme shorter than phallus.

Female. Unknown.

Distribution.

China (Chongqing).

Remarks.

The new species resembles Homoneura (Homoneura) apiconcava in the habitus and abdominal tergites 2–5 with blackish brown posterior margin [see You et al. 2023: figs 3, 5], but it can be distinguished from the latter by the following: mesonotum with acrostichal setulae in ten irregular rows; fore femur with eight posterior dorsal setae and ctenidium with 16 short setae; subcostal cell hyaline; surstylus consisting of a longer subuliform process and a shorter subuliform process in lateral view. In H. (H.) apiconcava , mesonotum with acrostichal setulae in eight irregular rows; fore femur with ten posterior dorsal setae and ctenidium with 12 short setae; subcostal cell pale brown apically; surstylus with concavity apically in lateral view [see You et al. 2023: figs 2–6].

Figures

Figures 1–5. Homoneura (Homoneura) biconica sp. nov. male 1 head, anterior view 2 wing 3 habitus, lateral view 4 thorax, dorsal view 5 abdomen, dorsal view.

Figures 6–10. Homoneura (Homoneura) biconica sp. nov. male 6 syntergosternite and epandrium, lateral view 7 epandrial complex, posterior view 8 syntergosternite, anterior view 9 phallic complex, ventral view 10 phallic complex, lateral view. Scale bar: 0.5 mm.