Key to species groups of Melolontha known from India (adopted and modified from Li et al. 2010)

1. Elytral disc glabrous or setiferous; colour of elytra light olive to dark green........................................ 2

– Elytral disc with dense setae; colour of elytra dark brown to yellowish-brown...................................... 3

2. Pronotum shining dorsally, lacking metallic reflection; elytron with one post-humeral and 2 to 3 basal setiferous patches (Fig. 1); apex of interval one deeply depressed along elytral disc; parameres with ventroapical process, distinctly elongate and gradually acuminate in lateral view (Fig. 53), lateral convexity completely absent (Fig. 41)............... guttigera group

– Pronotum with dorsal metallic with green reflection; elytra without patches of setae at base (Fig. 2); apex of interval one weakly depressed along elytral disc; parameres without a ventroapical process (Fig. 54), lateral convexity weakly developed (Fig. 42) ........................................................................................ virescens group

3. Basal segment of antenna swollen at apex, with antennomeres 2 and 3 compressed (see Li et al. 2010, fig. 1) (Figs. 26, 34, 66); antennal club strongly to moderately curved outwardly (Figs 25, 33, 66); length of dense setae more on vertex than those of clypeus (Figs. 25, 33, 66); setae on inner surface of meso- and metatibiae stout and long (Figs. 31, 37)................ … 4

– Basal segment of antennae moderately swollen apically, antennomeres 2 and 3 elongate (see Li et al. 2010, fig. 2); antennal club weakly to moderately curved outwardly (see Li et al. 2010, figs. 4, 5, 6); length of setae on vertex same as those on clypeus; setae on inner surface of meso- and metatibiae stout and short.................................................. 5

4. Antennal club strongly curved outwardly, 3.5 times as length of basal segments (see Li et al. 2010, fig. 3) (Figs. 25, 33, 66); outer metatibial spur subequal in length to length of metatarsomeres 1 and 2 combined (Figs. 31, 37); apical portion of pygidium not narrowed, more or less rounded (Figs. 15, 16); parameres symmetrical, apical process of left paramere not raised (Figs. 43, 44, 70)....................................................................... phupanensis group

– Antennal club moderately curved outwardly, three times as length of basal segments; outer metatibial spur subequal to length of metatarsomere 1; apical portion of pygidium narrowed to form an elongate process (Figs 17, 18); parameres asymmetrical, apical process of left paramere relatively raised (Figs 45, 46)...................................... aeneicollis group

5. Antennal club relatively shorter, weakly curved (see Li et al. 2010, fig. 6) (Fig. 7); pronotum with irregular serrations laterally; parameres with sharply developed pointed process at outer margin in dorsal view (Fig. 47).............. .. chinensis group

– Antennal club usually longer and moderately curved (see Li et al. 2010, figs. 4, 5) (Figs. 8–12); pronotum with serrations developed anteriorly with basal one–half to one–third of margin smooth (see Li et al. 2010, fig. 8); parameres without pointed process (Figs. 48–52).................................................................................. 6

6. Central disc of pronotum evenly and densely punctate; midline of pygidium ridged completely or incompletely (Figs. 20–22); apical and dorsal process (Figs. 48–50) and lateral convexity of paramere well developed (Figs. 60–62)..... .. carinata group

– Central disc of pronotum unevenly punctured; midline of pygidium smooth (Figs 23–24); apical process of paramere distinctly enlarged posteriorly, fusing with dorsal process (Figs. 51–52), lateral convexity broadly swollen laterally (Figs. 63–64)............................................................................................... incana group