In 2006, a parasitoid wasp (Microctonus aethiopoides) was released in New Zealand to help suppress clover root weevil populations. This wasp is smaller than a sandfly and prefers to attack clover root weevil (CRW) over other weevil species.
To complete its life cycle, the wasp lays an egg inside a CRW adult. This immediately stops the weevil from being reproductive. Wasps will parasitise many CRW in their lifetime. The wasp egg develops inside the sterile weevil and eventually a parasitoid larva emerges, killing the weevil. This larva forms a cocoon in the pasture litter from which a new adult wasp will emerge.
