Key to the Malagasy species of Anthobosca

1 Ten flagellomeres; six metasomal segments; females .................................................................................................. 2

- Eleven flagellomeres; seven metasomal segments; males............................................................................................ 4

2 Head, mesosoma and metasoma brown; wing membrane amber-tinted; body length over 25 mm ... insularis F. Smith

- Head, mesosoma and metasoma blackish or blackish and red, often with whitish spots; body length less than 15 mm ...................................................................................................................................................................................... 3

3 Metasoma red, terga II and III without whitish lateral spots. ....................................................... dimidiata Bartalucci

- Metasoma black to dark brown, with whitish lateral spots on terga II and III. .......................... madecassa Krombein

4 Metasomal sterna II and III with large spoon-like ventral projections (Fig. 4); flagellomeres with ovoid tyloids on VI–XI (Fig. 4) and large ovoid flat patch on V–X; metasoma with extensive yellow markings ................................... ................................................................................................................................ hallucigenia Kimsey, new species

- Metasomal sterna II and III unmodified, without projections; flagellomeres absent or present on VI–X or VII–XI; metasoma without yellow markings ............................................................................................................................. 5

5 Body length 17–20 mm; wings dark amber-tinted; flagellomeres without tyloids; tegula brown ..... insularis F. Smith

- Body length 11 mm or less; wings untinted; three or more flagellomeres with tyloids; tegula white ......................... 7

6 Flagellomere XI less than 2.2x as long as broad .......................................................................................................... 7

- Flagellomere XI more than 2.4x as long as broad ...................................................................................................... 10

7 Flagellomere VIII without tyloid; clypeus entirely white, evenly convex with narrow ventrally facing flattened sur- face.............................................................................................................................................. micromeria Bartalucci

- Flagellomere VIII with tyloid; clypeus variously colored, without ventrally facing flattened surface........................8

8 Flagellomere VII with small, ovoid tyloid............................................................... nigrimacula Kimsey, new species

- Flagellomere VII without tyloid ...................................................................................................................................9

9 Volsella broadest dorsally, dorsal lobe oriented horizontally (Fig. 34); paramere apex whitish .................................... .................................................................................................................................. toliaraensis Kimsey, new species

- Volsella broadest submedially, dorsal lobe oriented diagonally (Fig. 25); paramere apex brown ................................. ....................................................................................................................................... castanea Kimsey, new species

10 Paramere apex white; flagellum strongly bicolored brown to black dorsally and yellow ventrally; digitus extending diagonally to horizontally toward paramere in lateral view ....................................................................................... 11

- Paramere apex brown; flagellum brown to black, may be slightly paler ventrally; digitus extending diagonally toward paramere in lateral view.................................................................................................................................. 12

11 Volsella broadest dorsally, digitus horizontally oriented in lateral view (Fig. 20); clypeus gently convex medially, entirely white or less commonly bicolored, black and white............................. mahajangaensis Kimsey, new species

- Volsella narrowed dorsally, digitus oriented obliquely in lateral view (Fig. 22); clypeus flattened medially, entirely brown or bicolored brown and black ................................................................... namorokaensis Kimsey, new species

12 Flagellomere XI 2.3–2.4x as long as broad; digitus horizontally oriented in lateral view (Fig. 16) .............................. ........................................................................................................................................... fisheri Kimsey, new species

- Flagellomere XI 2.6–3.0x as long as broad; digitus diagonally to vertically oriented in lateral view (Fig. 18). ........... .................................................................................................................................... harinhalai Kimsey, new species