Adult black vine weevils are approximately 9 mm long and dull black with dirty yellow marks on the wing covers. The wing covers are grooved and fused with the body; therefore, they cannot fly but can walk very well. The larvae of black vine weevil, commonly known as grubs are up to 10 mm long, white in colour, plump c-shaped, and legless with a light brown head.
Outdoors there is a single generation each year. Black vine weevil develops through four life stages:Â egg, larva, pupa, and adult. Each female is capable of laying 1000 or more eggs in the ground. The eggs hatch in the soil and larvae live in the root zone where they feed on the roots. Overwintering occurs in the late larval stage. In spring, they change to pupae and begin emerging as adults. Black vine weevils are generally parthenogenetic, meaning the female reproduces asexually, and a single female is enough to start a new population. As they cannot fly, their dispersal ability is limited compared to many other insects. Vine weevils usually spread over longer distances with infested plant material.
Black vine weevil is a widespread pest of pot plants as well as plants growing in the ground. The most serious damage is caused by feeding the larvae on the roots, weakening growth, and often killing plants. Adult black vine weevils feed on plant foliage and leave distinctive bite marks on vegetation, with irregular-shaped notches of leaf margins.
