Homoneura laticosta (Thomson, 1869)

Zhang, Mengjing, Gao, Xuefeng & Shi, Li, 2019, Three new species of genus Homoneura from Qinling Mountains, China (Diptera: Lauxaniidae), Zoological Systematics 44 (2), pp. 146-157 : 150

laticosta -group

Diagnosis. The species group is different from other species groups by following: wing with narrow brown or broad deep brown area which extends from costal margin to R 4+5 or M 1 or CuA 1, and a brown stripe-like spot is present on crossvein r-m and/or dm-cu or absent. Male genitalia are different by: surstylus with 1–3 processes; hypandrium H or U-shaped or narrow transverse bar-like.

Key to the nine species in laticosta -group (modified from Shen et al., 2018).

1. Wing sapromyziform, with small costal black spines extending slightly before apex of R 4+5; male genitalia: surstylus long and hooked with a sharp apex (see Shewell, 1971: plate II, fig. 9) ..................................................................................... H. (H.) kaszabi Shewell Wing homoneuriform, with small costal black spines extending to apex of R 4+5; male genitalia not as above.................................... 2

2. Wing with broad deep brown area extending from costal margin to M 1 and a dark stripe on CuA 1 (see Kertész, 1915: fig. 9); mesonotum with a broad grayish brown medial stripe and a pair of postsutural lateral spots and short lateral stripes .......................... ................................................................................................................................................................ H. (H.) discoidalis (Kertész) Wing with brown area extending from costal margin to tip of R 4+5 or M 1, but no dark stripes on CuA 1; mesonotum without pattern as above.................................................................................................................................................................................................... 3

3. Mesonotum with a blackish gray area between postpronotum on anterior margin, a pair of blackish gray postsutural lateral stripes extending to postsutural third dorsocentral seta; acrostichal setae in 4 rows; katepisternum blackish gray on lower part..................... .................................................................................................................................................................... H. (H.) czernyi Shatalkin Mesonotum yellow or yellowish brown, without pattern as above; acrostichal setae in 6–8 rows; katepisternum yellow ..................4

4. Mesonotum with a pair of brown medial stripes between dorsocentral setae rows; abdominal tergites 1–4 blackish brown except for yellow lateral margin and tergites 5–6 blackish brown; surstylus bifurcated apically in lateral view (see Sasakawa, 2002: fig. 14)..... ............................................................................................................................................................. H. (H.) yehliuensis Sasakawa Mesonotum without brown stripes; abdomen yellow; surstylus not as above...................................................................................... 5

5. Arista pubescent, with longest ray about 1/4 height of 1st flagellomere; surstylus hooked apically in lateral and posterior views (see Shi & Yang, 2014: figs 123−125).................................................................................................................. H. (H.) grahami Malloch Arista plumose, with longest ray longer than 1/3 height of 1st flagellomere; surstylus not as above ..................................................6

6. Wing with brown spots on crossvein r-m and dm-cu ........................................................................................................................... 7 Wing without brown spots on crossvein r-m and dm-cu or only brown spot on dm-cu ....................................................................... 8

7. Antennal 1st flagellomere yellowish brown on apical half; abdominal tergites 3–4 or 3–6 with a small brown medial spot; surstylus consisting of an anterior ventral process and a short apical process in lateral view (see Yang et al, 2002: figs 17–18)......................... ......................................................................................................................................................... H. (H.) obtusa Yang, Hu & Zhu Antennal 1st flagellomere entirely yellow; abdominal tergites without brown spots; surstylus with two sharp processes in lateral view ( Fig. 17 ) ............................................................................................................................. H. (H.) xunyangensis Gao & Shi sp. nov.

8. Wing only with brown spot on dm-cu; surstylus short, slightly curved and acute apically in lateral view (see Shi & Yang, 2014: fig. 147) .......................................................................................................................................................... H. (H.) laticosta (Thomson) Wing without brown spot on crossvein r-m and dm-cu; surstylus long and curled upward in lateral view (see Gao & Yang, 2002: figs 7−8)............................................................................................................................................................ H. (H.) longa Gao & Yang

Figures

Figures 17–21. Homoneura (Homoneura) xunyangensis Gao & Shi sp. nov., paratype, male genitalia. 17. Syntergosternite and epandrial complex, lateral view. 18. Epandrial complex, posterior view. 19. Syntergosternite, anterior view. 20. Phallus complex, ventral view. 21. Phallus complex, lateral view. Scale bar=0.1mm.