Olbiogaster Osten Sacken, 1886

Huerta, Heron, Dzul-Manzanilla, Felipe, Navarrete-Carballo, Juan C., Manrique-Saide, Pablo & Hancock, E. Geoffrey, 2019, Olbiogaster Osten Sacken (Diptera: Anisopodidae) from Mexico, with the description of three new species, Zootaxa 4565 (4), pp. 475-492 : 476-477

Key to the Mexican species of Olbiogaster Osten Sacken

Olbiogaster mexicana Lane & d'Andretta is only known from females. Regarding Olbiogaster sackeni Edwards and O. taeniata (Bellardi) the description of females included some characteristics indicated in the key of Lane & d'Andretta (1958: 514). Peterson (1981) added some illustrations of the wing, thorax, tarsomere and claw of Olbiogaster sackeni Edwards.

1. Male................................................................................................ 2 - Female.............................................................................................. 6 2(1). Front coxa yellow...................................................................... O. sackeni Edwards

- Front coxa dark brown................................................................................. 3

3(2). Hind femur dark brown with basal or distal yellow ring....................................................... 4

- Hind femur completely dark brown ( Fig. 9C ).................................................... O. puuc sp. nov.

4(3). Mesonotum with a dark brown central stripe, surrounded U-shaped black stripe ( Fig. 2C ); sternite 10 with elongated slender arms, apically with a long spine, curved ( Fig. 6J )................................................ O. nuxco sp. nov.

- Mesonotum with different pattern; sternite 10 with elongated slender arms, apically with spine, slightly curved or a few setae5

5(4). Hind femur basal and apical 1/3 dark, middle 1/3 yellow; sternite 10 with elongated slender arms, apically not widened ( Fig. 6D).................................................................................. O. halffteri sp. nov.

- Hind femur dark, except for yellow apex; sternite 10 with elongated slender arms, apically enlarged.... O. taeniata (Bellardi)

6(1). Coxae mostly blackish brown; hind femur entirely yellowish.......................... O. mexicana Lane & d´Andretta

- Fore and midcoxae yellow, with dark brown tinge; hind coxae dark brown; hind femur dark, except for basal 2/3 yellow ring ( Fig. 7C )............................................................................... O. nuxco sp. nov.

Figures

FIGURE 2. Olbiogaster nuxco sp. nov. Male paratype, A. Antenna; B. Head, frontal view; C. Thorax, dorsal view. Scale bar: A-B=0.5 mm, C=1.0 mm.

FIGURE 6. Male genitalia, ventral view. A–D. Olbiogaster halffteri sp. nov.; E–G. Olbiogaster nuxco sp. nov.; H–J. Olbiogaster puuc sp. nov. Aedeagal guide: A, B, E, H; gonostylus: C, F, I; sternite X: D, G, J. Scale bar: A, C, D= 0.1 mm; E– J= 0.16 mm.

FIGURE 7. Olbiogaster nuxco sp. nov. Female paratype, A. head, thorax and first and second segment abdominal, dorsal view; B. head and thorax, lateral view; C. Legs, top: hind leg, middle: midleg, lower: foreleg, lateral view; D. Abdomen, dorsal view; E. genitalia, ventral view. Scale bar: A, B, D=1.0 mm; C=0.1 mm, E=0.05 mm.

FIGURE 9. Olbiogaster puuc sp. nov. Male holotype, Legs, lateral view. A. foreleg, B. midleg, C. hind leg. Abbreviations. cx= coxa; fe= femur; tb= tibia; tr= trochanter; tsm= tarsomere 1 to 5. Scale bar= 0.1 mm.