The feeding habits and infestation of the bitterleaf weevil, Lixus camerunus Kolbe, were investigated in Rivers State, Nigeria. Vernonia amygdalina was the only species preferred for feeding and oviposition by adult L. camerunus, among the species (Talinum triangulare (Jacq.) Wild, Telfairia occidenlalis Hooker fil, Amaranthus hybridus L., Solanum melongena, Capsicum sp., Chromalaena odorata (Eupatorium odoralum) L., Emilia praetermissa L.) associated with V. amygdalina in farms, that were offered. There was a significant correlation between dry weight of foliage consumed and weight of males and females.
Initial tunnelling direction by larvae was upwards, but on the death of shoots, larvae reversed direction and moved downwards along old tunnels. However, newly-emerged larvae in leaf petioles, tunnelled downwards to the main branch, before pursuing an upward course. In addition to main tunnels, there were also branch tunnels. There was a significant negative correlation between length of tunnel and stem diameter. There was a significant negative correlation between gall/stem diameter ratio and stem diameter.
L. camerunus is widely distributed in the State.