Species Scolia dubia - Blue-winged Wasp

Digger Wasp

Scolia dubia Say, 1837

Latin dubia means "doubtful" (Internet searches).

20-25 mm (U. of Florida)

Black with reddish orange abdomen, two large yellow spots.

The larva is a legless, white grub with a brown head. It appears hairless and has no eyes. The antennae, maxillary and labial palps are one-segmented. There is a slit-like silk gland on the labium.

Males have longer antennae than females, and a pronglike pseudostinger on the abdomen.

Massachusetts to Florida, west to Colorado, Arizona, California.

Summer, early fall. June-October (North Carolina).

Adults take nectar, may also feed on juices from beetle prey.

Larvae are parasites of green June beetles and Japanese beetles.

Males and females have a courtship dance, flying close to the ground in a figure-8 or S pattern. Females burrow into ground in search of grubs, especially those of the Green June Beetle, Cotinis, and the Japanese Beetle Popillia japonica. She stings it and often burrows farther down, then constructs a cell and lays an egg on the host. Larva pupates and overwinters in a cocoon within the body of the host. One generation per year in North, more in South.

Males have a three pronged "pseudostinger," which is part of their external genitalia.