Immature or larval stage is a white to creamy-white, soft bodied curl grub up to 25mm long. Similar to African Black Beetle with three sets of legs and a hard, light brown head capsule, but appears in larger numbers and is more active. When mature the adult beetle is olive in colour with distinct brown markings on the wing casing and a soft shell, up to 15mm long.
Biology and Lifecycle
The Argentine Scarab has a one year lifecycle comprising of 2-4 weeks as an eggs, 10-11 months as larvae, 4-5 days as pupae and 1-4 weeks as adults. Adults emerge from the pupal stage at the beginning of summer when soil temperatures begin to warm. After mating, females burrow into soft, moist soils and deposit eggs in the upper soil profile. The eggs hatch 2-4 weeks later and larvae begin to feed on turf roots. Larvae grow quickly and reach 3rd instar within several weeks. In about May or June the 3rd instar larvae begin to move underground to overwinter within the soil.