Key to the known larvae of Neuroleon

1 Dorsal side of the head capsule mostly covered by large contiguous black markings (Fig. 16)......................... 2

- Dorsal side of the head capsule without extended black markings (Fig. 13–15, 17)..................................3

2 Ventral side of the head capsule pale; general colour of the body whitish................................. N. ochreatus

- Ventral side of the head capsule infuscated; general colour of the body ochre (Fig. 16).................... N. microstenus

3 Ventral portion of the head capsule with a pair of median markings (except those on the gular area); general colour of the body brown (Figs. 14, 15)................................................................................... 4

- Ventral portion of the head capsule without a pair of median markings (except those on the gular area); general colour of the body ochre (Figs. 13, 17)............................................................................... 5

4 Mandibles relatively thin, distance between base and the basal tooth equal to that between the basal and apical teeth; ventral side of the head capsule with a median pair of separated spots; labial palpi dark (Fig. 14).................... N. assimilis

- Mandibles relatively robust, distance between base and basal tooth smaller than that between the basal and apical teeth; ventral side of the head capsule with a median pair of contiguous parallel stripes; labial palpi pale (Fig. 15)............. N. egenus

5 Dorsal side of the head with an anterior pair of brown markings disposed from the antennal pit to the posterior V-shaped markings (Fig. 13)................................................................................ N. arenarius

- Dorsal side of the head without an anterior pair of dark markings (Fig. 17)............................ N. nemausiensis