Zamia weevil

The Zamia weevil (Rhopalotria slossoni) belongs to the order Coleoptera and the family Curculionidae. It is a specialized pest known for infesting plants within the order Cycadales, specifically focusing on the genus Zamia.

These insects primarily target the reproductive structures of their host plants. In agricultural and ornamental settings, such as nurseries and conservatories, they pose a significant threat to the production and health of various cycad species, causing economic losses for growers of exotic plants.

The biology of Rhopalotria slossoni is strictly tied to the life cycle of the host plant. Female weevils lay their eggs within the female cones (strobili). Upon hatching, the larvae bore into the cone, feeding on the developing seeds and internal tissues, which is essential for their development and maturation.

The damage caused by these weevils is often internal and can be difficult to detect in the early stages. As larvae feed, they destroy the seeds, rendering them non-viable. This leads to a decline in plant propagation success and can severely deform or kill the strobili prematurely.

Management strategies for this pest include:

• Regular inspection of female cones for signs of entry holes.
• Physical removal and destruction of infested cones to interrupt the life cycle.
• Application of appropriate insecticides during the mating and egg-laying phases.
• Implementation of strict quarantine protocols for new plants entering a collection or nursery.