Twobanded Japanese Weevil – Callirhopalis bifasciatus
Twobanded Japanese Weevil (Callirhopalis bifasciatus)
Common Name: Twobanded Japanese Weevil
Latin Name: Callirhopalis bifasciatus
Appearance:
Adults:
This flightless beetle has a pear-shaped snout and elytra that are substantially wider than the pronotum. It measures around 14 inches long and has brown and grey scales that create bands over the elytra. This bug lacks flight because its elytra are glued together.
Larvae:
White, legless larvae size 7.5-8.5 mm. The pupa is 6.25mm long and white with yellow-brown setae.
Host plant:
The twobanded Japanese weevil attacks cherry laurel, evergreens, pyracantha, privet, barberry, and euonymus. Florida specimens came from a soybean field.
Territory:
Twobanded Japanese Weevils are native to China, Japan, Korea, Mongolia, and eastern Siberia.
Damages caused by Twobanded Japanese Weevil:
When in large numbers, adult twobanded Japanese weevils can seriously harm landscape plantings in particular because they feed on the leaves of a wide variety of host plants.
Life history and habits:
The twobanded Japanese weevils reproduce parthenogenically (no males) and overwinter as adults, eggs, or larvae. The overwintering adults become active when the temperature warms up, and they resume eating. From May through October, eggs are placed on leaf folds, with the peak oviposition period occurring from September to early October. By November, oviposition had ceased. The eggs hatch in 14-18 days and the freshly formed larvae drown and burrow into the earth to feed on the roots. Larvae have been discovered at depths ranging from 1 to 9 inches below the surface. After pupating, the larvae emerge as adults and return to the upper surface to feed on the host plant.