Bregmosina

Marshall, Stephen A., 2013, Bregmosina, a new Neotropical genus of Limosininae (Diptera: Sphaeroceridae), Zootaxa 3641 (3), pp. 260-270 : 262

Key to the species of Bregmosina

1) Lower orbital bristle conspicuously finer and less than half as long as upper orbital bristle. Male sternite 5 made up mostly of two strikingly stout, long posterolateral processes ( Fig. 20 ). Length (antennal base to wing tip) less than 2.3 mm .......... 2

- Both orbital bristles well developed, lower bristle at least half as long as upper ( Fig. 8 ). Male sternite 5 without long posterolateral processes. Length (antennal base to wing tip) over 2.5 mm ................................................. 3

2) Sternite 4 of male with two short posteromedial lobes ( Fig. 20 ). Surstylus strongly recurved, apex long and pointed, much longer than width of surstylus ( Fig. 21 ).............................................. B. obunca . Costa Rica, Guyana

- Sternite 4 of male without posteromedial lobes. Surstylus club-like, apex swollen with a short pointed process shorter than width of surstylus ( Fig. 22 )............................................................. B. howdeni . Ecuador

3) Male cercus with ventral point ( Figs. 12 , 23 ). Postgonite either very broad at middle or swollen at apex ( Figs. 14 , 26 ). Either second costal sector longer than third or R2+3 slightly sinuate ( Fig. 10 ). Fore tarsomeres 2–4 and sometimes apex of tarsomere 1 flattened and wider than base of tarsomere 1. Known females with tergite 8 not shortened dorsally, longer than cercus ( Fig. 16 )..................................................................................................... 4

- Male cercus subquadrate, without ventral point ( Fig. 5 ). Postgonite narrow, simple ( Fig. 6 ). R2+3 not distinctly sinuate and second costal sector shorter than third ( Fig. 3 ). Fore tarsomeres 3–4 short and slightly swollen but not distinctly wider than tarsomere 1. Female tergite 8 short dorsally, no longer than cercus ( Fig. 1 ).......................... B. bucki Costa Rica

4) Fore tarsomeres 2–5 short and flat, tarsomere 1 almost parallel sided, not distally swollen ( Fig. 7 ). R2+3 slightly sinuate, curved up at apex ( Fig. 10 ). Eye relatively small, less than 2.5X genal height. Male abdominal sternites 2 and 3 entire................................................................................ B. ephydriformia . Costa Rica, Venezuela

- Fore tarsomeres 1–4 strikingly swollen and flattened, tarsus strongly spindle-shaped. R2+3 straight, slightly curved only at apex. Eye larger, over 2.5X genal height. Male with all abdominal sternites medially divided ( Fig. 24 )... B. schizosterna . Ecuador.

Figures

FIGURES 18 – 22. Bregmosina obunca and B. howdeni. 18, B. obunca female terminalia; 19, B. obunca aedeagus and associated structures left lateral; 20, B. obunca male terminalia ventral; 21, B. obunca epandrium and associated structures left lateral; 22, B. howdeni epandrium and associated structures left lateral. Abbreviations: SP, spermatheca; T 7, T 8, S 5, S 7, S 8, sternites and tergites; P, phallapodeme; PG, postgonite; H, hypandrium; C, cercus; B, basiphallus; D, distiphallus; SU, surstylus.

FIGURES 7 – 9. Bregmosina ephydriformia. 7, female, entire dorsolateral; 8, head and anterior scutum; 9, male, entire ventral.

FIGURES 10 – 17. Bregmosina ephydriformia. 10, male wing; 11, head; 12, male terminalia ventral; 13, epandrium and associated structures left lateral; 14, aedeagus and associated structures left lateral; 15, spermathecae; 16, female terminalia lateral; 17, female terminalia dorsal.

FIGURES 23 – 26. Bregmosina schizosterna. 23, male terminalia posterior; 24, male terminalia ventral / lateroventral (detail given for only left side of sternite 5); 25, epandrium and associated structures left lateral; 26, aedeagus and associated structures left lateral. Abbreviations: D, distiphallus; PG, postgonite; SU, surstylus; S 4 – 7, sternites 4 – 7.

FIGURES 1 – 6. Bregmosina bucki. 1, female terminalia lateral; 2, spermathecae; 3, male wing; 4, male terminalia ventral; 5, epandrium and associated structures left lateral; 6, aedeagus and associated structures left lateral. Abbreviations: T 7, T 8, S 5, S 7, S 8, sternites and tergites; P, phallapodeme; PG, postgonite; H, hypandrium; C, cercus; D, distiphallus; SU, surstylus.