Key to the species of the Microserica lineata group

1 Phallobase short, about twice as long as wide in right side lateral view (Figs. 1F, I). Pronotum yellowish with one or two dark spots................................................................................................ 2

- Phallobase long, more than three times longer than wide in right side lateral view (Figs. 1C, M). Pronotum uniformly brown ................................................................................................... 3

2 Pronotum yellowish with one median dark spot. Right paramere long, its apex strongly widened apically (Fig. 1B). Antennal club little longer than the remaining antennomeres combined................................ M. lineata Moser, 1915

- Pronotum yellowish with two symmetric dark spots beside the dark midline. Right paramere short, its apex weakly widened apically (Fig. 1K). Antennal club twice as long as the remaining antennomeres combined..... M. geberbauer Ahrens, 2004

3 Left lateral process of phallobase strongly widened apically but straight (Fig. 1D)................................... 5

- Left lateral process of phallobase narrow and not widened apically...............................................4

4 Left lateral process of phallobase strongly hooked ventrally at apex (Fig. 1G). Body densely covered with small white setae. Body smaller, 6.8–7.1 mm. Anterior margin of metafemur with serrated line.............. M. crenatostriata Ahrens, 2004

- Left lateral process of phallobase evenly narrowed towards apex (Fig. 3I). Serrated line beside anterior margin of metafemur and beside dorsal margin of metatibia lacking...................... M. tenasserimensis Bohacz & Ahrens, new species

5 Ventral lamina of left side of phallobase strongly produced ventrally, phallobase results distally strongly widened (Fig. 2A).................................................................. M. ventrosa Bohacz & Ahrens, new species

- Ventral lamina of left side of phallobase not produced (Fig. 1D), phallobase distally not widened....................... 6

6 Body densely covered with small white scales. Right paramere short and wide............… M. squamulata (Moser, 1915)

- Body sparsely covered with small white scales, only with dense, white minute setae................................. 7

7 Right paramere robust and elongate, width subequal to maximum phallobase width................................. 8

- Right paramere narrow and curved, width much narrower than maximum phallobase width.............................................................................................. M. helferi Bohacz & Ahrens, new species

8 Base of labroclypeus dull. Dorsal margin of right paramere evenly curved (lateral view)................................................................................................ M. ginae Bohacz & Ahrens, new species

- Base of labroclypeus shiny. Dorsal margin of right paramere strongly bent at middle and concave basally (lateral view).................................................................. .. M. banvaneue Bohacz & Ahrens, new species