Key to Thailand species of Agromyza

1. Calypter with fringe yellow to ochreous.................................................................... 2

- Calypter with fringe dark brown to black.................................................................. 4

2. Costa terminating at R4+5; mesoscutum matt black, with only posteriormost dc distinct; tarsi black; distiphallus tubular (Spencer 1990: fig. 1361)(India, Thaialnd; host plant: Pennisetum typhoideum).......... Agromyza pennisetivora Spencer (1961)

- Costa extending to M1; mesoscutum shining black, more than one distinct dc; tarsi brownish yellow to brown; distiphallus tubular or globular..................................................................................... 3

3. Mesoscutum with second and third postsutural dc distinct, presutural and first postsutural dc extremely short; distiphallus tubular (Sasakawa 1961: fig. 10d)(Europe; India, Laos, Thailand, Malaysia, Taiwan; host plant: Phragmites communis)..................................................................................... A. phragmitidis Hendel (1922)

- Mesoscutum with 1+4 or 0+3 dc (presutural and first postsutural dc distinct); distiphallus globular (Taiwan, Thailand).................................................................................. A. flavisquama Malloch (1914)

4. Ocellar triangle with oc short; ori four (3–5); distiphallus tubular, spinulose distally (Sasakawa 1961: fig. 8A) (Japan; Taiwan, Thailand; host plants: Oryza sativa, Zizania latifolia).................................... A. oryzae (Munakata, 1910)

- oc long; ori 2–3....................................................................................... 5

5. Fore tibia with an external pd; distiphallus with tubules distally (Spencer 1962a: fig. 2b)(Myanmar, Thailand, Taiwan)...................................................................................... A. comosa Spencer (1962)

- Fore tibia without pd; distiphallus without tubules........................................................... 6

6. Distiphallus with basal part distinctly longer than distal part (Spencer 1986: figs 1, 2)(Indonesia, Thailand; host plant; Panicum palmifolium)...................................................................... A. panici Meijere (1934)

- Distiphallus with basal part subequal to distal subglobular lobe (Sasakawa 1972: fig.2)(Taiwan, Thailand; host plant: Digitaria spp.).......................................................................... A. latipennis Malloch (1914)