Palms infested with palmetto weevil (Rhynchophorus cruentatus) may show a number of collapsed leaves hanging along the trunk. In severe infestations, the entire crown of a palm may fall over or drop off due to extensive burrowing by the larvae (Figs. 1 and 2). Older leaves can easily be pulled out, revealing damaged petioles and leaf bases (Fig. 3).
Silky sugar cane weevil (Metamasius hemipterus) cause similar damage to leaf bases and petioles, but holes are much smaller. Banana moth (Opogona sacchari) larvae cause similar damage within palm trunks.
Damage to leaf petioles and bases is caused by the burrowing of early instar larvae of several species of Rhynchophorus. Later instar larvae can burrow into the trunk tissue and potentially destroy the meristem.
Rhynchophorus cruentatus is a serious problem on Phoenix canariensis, Bismarckia nobilis, and other species in Florida, while R. palmarum is a pest of Elaeis guineensis, Cocos nucifera, and other species in Central and South America, R. ferrugineus is a problem on Phoenix dactylifera in the Arabian Gulf area and on Cocos nucifera in the Philippines and Southeast Asia but has been found in California, and R. phoenicis is a pest on Elaeis guineensis, Phoenix spp., and Borassus sp. in Central and Southern Africa.