Forest Pest Insects in North America: a Photographic Guide

Red palm weevil

Rhynchophorus ferrugineus (Olivier) (Coleoptera: Dryophthoridae)

Orientation to pest

The red palm weevil, Rhynchophorus ferrugineus (Olivier), is native to south Asia and Melanesia, where it is a serious pest of palms. Since the 1980s, this weevil has spread rapidly throughout many other parts of the world, reaching the United States (southern California) in 2010. The adult is 2-5 cm long and usually rusty red, but color variants are common. Larvae feed by tunneling in the trunks of palm trees, weakening and eventually killing trees. Red palm weevil is a major pest of date palms (Phoenix dactylifera L.) and coconut palms (Cocos nucifera L.). Palms damaged by red palm weevil show (1) foliage injuries that include straight edges instead of pointed tips, notching of lateral pinnae, and sometimes a linear series of "windows" across pinnae, (2) tunnels in the trunk or at the base of fronds, (3) oozing of viscous fluids from tunnels; (4) frass at entrance of feeding tunnels, (5) empty pupal cases and the bodies of dead adults around heavily infested palms, and (6) breaking of the trunk, or toppling of the palm crown. This weevil is a pest of both cultivation (agricultural or landscaping palms) and native palms in wildlands.

Hosts commonly attacked

The red palm weevil is especially damaging economically to date palms (P. dactylifera) and coconut palms (C. nucifera). Other hosts that have been recorded include palms in the genera Areca, Arenga, Borassus, Caryota, Corypha, Livistona, Metroxylon, Oreodoxa, Sabal, Trachycarpus, and Washingtonia. Of potential concern in the United States is the risk to native palms in the genera Washingtonia and Sabal.

Distribution

Red palm weevil is from south Asia and Melanesia, but since the 1980s, it has spread to Africa, Mediterranean Europe, the Caribbean, and southern California (USA).

Images of red palm weevil

Adult red palm weevil (dark form found in California) John Kabashima, UC Cooperative Extension, Bugwood.org 768x512 / 1536x1024
Larva and pupa of red palm weevil (red form of adult, from France) Christina Hoddle, University of California - Riverside, Bugwood.org 768x512 / 1536x1024
Red palm weevil lava in open pupal cell Mike Lewis, Center for Invasive Species Research, Bugwood.org 768x512 / 1536x1024
Figure 1. Adult red palm weevil (dark form found in California), Rhynchophorus ferrugineus Figure 2. Larva and pupa of red palm weevil (red form of adult, from France) Figure 3. Red palm weevil lava in open pupal cell
Palm frond with typical damage from red palm weevil Mike Lewis, Center for Invasive Species Research, Bugwood.org 768x512 / 1536x1024
Landscape palm damaged by invasive red palm weevils Christina Hoddle, University of California - Riverside, Bugwood.org 768x512 / 1536x1024
Native California fan palms at Mountain Palm Springs in Anza Borrego State Park in southern California may be hosts for red palm weevil. Bill Sullivan for ABDNHA, Bugwood.org 768x512
Figure 4. Palm frond with typical damage from red palm weevil Figure 5. Landscape palm damaged by invasive red palm weevils Figure 6. Native California fan palms, Washingtonia filifera (Lindl.) H.Wendl., at Mountain Palm Springs in Anza Borrego State Park in southern California may be hosts for red palm weevil.

Important biological control agents related to this pest species

Biological control of the red palm weevil has so far been focused on control methods that can be applied to agricultural palm plantations or landscape palms in urban areas. Should native palms in wildlands be affected, classical biological control (based on importation of parasitoids of the weevil from its native range) should be investigated.

Web links for information on red palm weevil

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