Scolia nobilitata tricincta

Distinguished from Scolia dubia by having four yellow or off-white spots on the abdomen (two pairs) rather than one pair of bright yellow spots. Wings are smoky brown rather than iridescent blue-black. From other Scolia species, the specific spot pattern and wing coloration are diagnostic, though precise distinguishing features from all congeners are not documented in available sources.

Lawns, landscape beds, and other areas with soil-dwelling scarab beetle grubs. Requires access to flowering plants for adult nectar feeding and suitable soil conditions for grub hunting.

Documented in the DMV region (Washington D.C., Maryland, Virginia); broader distribution of the species complex extends through eastern North America.

Adults active in August; larvae develop through summer and autumn; overwinters as pupa in cocoon within grub burrow.

Adults feed on nectar from flowers in Lamiaceae (mint family, including mountain mint) and Asteraceae (aster family, including goldenrod and spotted horse mint). Larvae are parasitoids that consume living scarab beetle grubs.

• Scarabaeidae - parasitoidLarval stages (white grubs) of green June beetles, Japanese beetles, Oriental beetles, Asiatic garden beetles, and other scarabs that dwell in soil

Adult wasps emerge in August. Female locates grub beneath soil surface, tunnels through dirt, delivers paralyzing sting, and deposits egg on grub's skin. Egg hatches; larva slowly consumes living grub. After completing development during summer and autumn, larva spins silken cocoon, pupates, and overwinters in the burrow. Fresh adults emerge the following August.

Adults fly in tight figure-eight patterns approximately one foot above turf, presumably searching for prey. Not aggressive toward humans. Females dig through soil to locate and parasitize grubs. Adults nectar on flowers before hunting.

Biological control agent of scarab beetle pests; functions as a parasitoid that suppresses populations of root-feeding grubs in lawns and gardens.

Beneficial insect that reduces populations of destructive lawn and garden pests including Japanese beetles and other scarab grubs. Can be encouraged by planting nectar sources such as mints and goldenrods. Not aggressive toward humans.

• Scolia dubiaSimilar size, shape, and ecology; distinguished by having two yellow spots (one pair) on abdomen versus four in S. nobilitata, and iridescent blue-black wings versus smoky brown wings

• parasitoid
• digger wasp
• biological control
• scarab pest
• beneficial insect

• BugGuide
• GBIF taxonomy match
• iNaturalist taxon
• Befriend wasps and they will befriend you: Digger wasps, Scolia dubia and Scolia nobilitata — Bug of the Week