Genus Glabellula Bezzi

Platygaster Zetterstedt, 1837: 54. Nomen nudum.

Platygaster Zetterstedt, 1838: 574. Type species: Platygaster arcticus Zetterstedt, 1838, by monotypy. [Preoccupied by Latreille, 1809.]

Sphaerogaster Zetterstedt, 1842: 232 (new replacement name for Platygaster Zetterstedt, 1838). Type species: Platygaster arcticus Zetterstedt, 1838, automatic. [Not preoccupied by Sturm, 1826.]

Glabella Loew, 1873: 210. Type species: Glabella femorata Loew, 1873, by monotypy. [Preoccupied by Swainson, 1840.]

Glabellula Bezzi, 1902: 191 (new replacement name for “ Platygaster ... und Sphaerogaster ... und Glabella ”). Type species: Platygaster arcticus Zetterstedt, 1838, by subsequent designation (I.C.Z.N., 1989: 148). [Name valid by I.C.Z.N. Code Article 23.9.2.]

Pachyneres Greene, 1924: 62. Type species: Pachyneres crassicornis Greene, 1924, by monotypy.

Proglabellula † Hennig, 1966: 15. Type species: Proglabellula electrica Hennig, 1966, by monotypy.

Diagnosis. Glabellula consists of minute flies, 1−2 mm in length; usually shiny black, with or without yellow markings; pubescence sparse, minute. The genus is distinguished from all other mythicomyiids based on the medial interruption of sclerotization on abdominal tergite 2 and in the wing by the tiny marginal cell of the wing formed by vein R 2+3 joining R 1 well before the costa, combined with cell bm united with cell dm (Fig. 4) (reformulated after the versions presented by Hall & Evenhuis (1984) and Evenhuis (2019)).

Identification key to South American species of Glabellula Bezzi

1 Mesonotum and scutellum entirely dark brown to black, without yellow areas (Figs 3, 14); tergites dark brown to black without yellow markings (Figs 2, 13)............................................................................ 2

- Mesonotum with submedian fine stripe formed by dense yellowish gray pruinosity and scutellum dark brown with yellow areas on posterior half and on anterior corners (Fig. 8); tergites dark brown to black with yellow markings (Fig. 7).................................................................................................. G. rafaelae sp. nov.

2 Femora dark brown to black; frons slightly depressed medially; female sternite 7 with lateral digitiform projections and medial shallow concave depression on posterior margin (Fig. 17)................................... G. catiapatiuae sp. nov.

- Femora dark brown to black with distal extremity dark yellow; frons not medially depressed; female sternite 7 without lateral digitiform projections and with medial deep concave depression on posterior margin (Fig. 19)......... G. sarahae sp. nov.