Opalimosina, Rohacek, 1983

Cao, Wenqiang, Yang, Ding & Dong, Hui, 2024, A review of Opalimosina Roháček, 1983 (Diptera, Sphaeroceridae) from China with new records and two new species, Zootaxa 5551 (2), pp. 353-368 : 354

Key to the species of China Opalimosina (males)

1. An additional small inclinate setula present between inner occipital bristles and outer occipital bristles; mid femur basally with a group of setae ( Roháček, 1985, Fig. 983); hind tibia without ventral preapical spur; S5 posteromedially with a large oval area, densely covered by small blunt cuticular projections ( Roháček, 1985, Fig. 1001)...................... O. czernyi (Duda)

-. No additional setula between inner occipital bristles and outer occipital bristles; mid femur simply finely setulose; hind tibia with distinct ventral preapical spur; S5 with paired posteromedial processes or spinose region or small patches........... 2

2. Sternite 5 with pair of long and ventrally curved posteromedial processes ( Figs. 2D , 6D )............................. 3

-. Sternite 5 with paired short and straight posteromedial processes or spiny region or small patches ( Deng et al., 2019, Fig. 5 ; Figs. 4B , 8D ; Hayashi, 1989, Fig. 4 ; Roháček, 1985, Fig. 1034; Su et al., 2013, Figs. 1g , 2f ).......................... 4

3. Sternite 5 with two clusters of robust spines between bases of posteromedial processes ( Fig. 2D ); hind tibia with a long curved long ventral preapical spur ( Fig. 1C ); posterior corner of surstylus with 1 long and robust bristle and 2 thinner setae ( Fig. 2C ); cercus with a long seta at posterodorsal margin( Fig. 2A )....................................... O. aculeata sp. nov.

-. Sternite 5 with a series of short setae between bases of processes ( Fig. 6D ); hind tibia with a very short, straight ventral preapical spur ( Fig. 5D ); posterior corner of surstylus with 2 robust (1 dorsal and 1 ventral) bristles ( Figs. 6B, 6C ); cercus with a short, stout and blunt medioventral spine ( Fig. 6A )........................................... O. setifera sp. nov.

4. C ending at R4+5..................................................................................... 5

-. C continuing distinctly beyond apex of R4+5............................................................... 8

5. Sternite 5 entirely sclerotized, posteromedially with two comb-like processes with setulae above, with two warts at base of processes and a row of small setae around warts anteriorly ( Deng et al., 2019, Fig. 5 )..................... O. verruca Su

-. Sternite 5 with membranous region, posteromedially with processes or small patches or dense small spines, without warts ( Figs. 4B , 8D ; Hayashi, 1989, Fig. 4 )........................................................................... 6

6. Sternite 5 with a longitudinally membranous region separating left and right halves; posterior margin of each part densely covered with small spines ( Hayashi, 1989, Fig. 4 )....................................... O. pseudomirabilis Hayashi

-. Sternite 5 with two characteristic processes or small patches posteriorly and a weakly sclerotized area centrally, never longitudinally divided ( Figs. 4B , 8D )...................................................................... 7

7. Sternite 5 posteromedially incised distinctly, with a pair of posterior processes at sides of incision and a weakly sclerotized, irregular area centrally ( Fig. 4B ), otherwise very densely and shortly setulose; epandrium with short sparse setulae ( Fig. 4A ); postgonite relatively straight ( Fig. 4D )................................................. O. calcarifera (Roháček)

-. Sternite 5 posteromedially incised weakly, with two small patches posteriorly and a weakly sclerotized, semicircular area centrally ( Fig. 8D ); postgonite sinuate ( Fig. 8E )............................................ O. spathulata Hayashi

8. Sternite 5 with an arc-shaped membranous stripe separating posteromedial part from anterior part, posteromedial part with densely long setose patches laterally and with a pair of cuticular structures on posterior margin ( Roháček, 1985, Fig. 1034); surstylus with 2 robust long setae and 1 smaller one at posterior corner ( Roháček, 1985, Fig. 1031)..... O. mirabilis (Collin)

-. Sternite 5 with a deep and narrow incision or intact posteromedially ( Su et al., 2013, Figs. 1g , 2f ); surstylus with 2 robust long setae at posterior corner ( Su et al., 2013, Figs. 1f , 2d )......................................................... 9

9. Sternite 5 with a deep and narrow incision posteromedially, a narrow membranous region centrally with a posterior row of robust setae, a dense row of spines at each side of incision and a setulose projection lateral to the row of spines ( Su et al., 2013, Fig. 1g ); postgonite sinuate and apex pointed................................................. O. differentialis Su

-. Sternite 5 posteromedially simple, with two small comb-like processes with setulae above, a dark arc-shaped stripe between processes and a row of long setae around stripe anteriorly ( Su et al., 2013, Fig. 2f ); postgonite with narrow and digitiform apex ( Su et al., 2013, Fig. 2c ).................................................................. O. prominentia Su

Figures

FIGURES 2. 2A–E. Opalimosina aculeata sp. nov. male habitus. 2A, lateral; 2B, dorsal; 2C, hind tibia anterior; 2D, mid tibia anterior; 2E, wing; 2F–G. female habitus. 2F, lateral; 2G, dorsal. Scale bars: (A–B, E–G) = 1 mm; (C) = 0.2 mm; (D) = 0.2 mm.

FIGURES 6. 6A–B. O. mirabilis (Collin, 1902) female habitus. 6A, dorsal; 6B, lateral; 6C–D. male habitus. 6C, dorsal; 6D, lateral. Scale bar:1 mm.

FIGURES 5. 5A–E. O. calcarifera (Roháček, 1975) structures of male postabdomen. 5A, terminalia posterior; 5B, S5 ventral; 5C, surstylus lateral; 5D, phallus and associated structures lateral; 5E, terminalia lateral. Scale bar: 0.1 mm.

FIGURES 4. 4A–B. O. calcarifera (Roháček, 1975) male habitus. 4A, dorsal; 4B, lateral. Scale bar: 1 mm.

FIGURES 8. 8A–B. O. prominentia Su, 2013 female postabdomen. 8A, dorsal; 8B, ventral. Scale bar: 0.1 mm.

FIGURES 1. 1A–B. O. czernyi (Duda, 1918) male habitus. 1A, dorsal; 1B, lateral. Scale bar:1 mm.