Further details on the finding of Paysandisia archon in France
As reported in EPPO RS 2002/011, Paysandisia archon (Lepidoptera: Castniidae) has recently been reported on palm trees in the south of France (Var département). Infestations were detected in several ‘communes’ (Six-Fours, Carqueiranne, La Londe, La Crau …). It is suspected that the pest was introduced from Argentina on imported Trithrinax campestris and Butia yatay plants. It can also be recalled that the same pest has also been recently introduced into Spain. It is now considered as widespread in the Province of Girona, and it was observed near Barcelona. Data is generally lacking on P. archon. Its geographical distribution is not known, but it includes at least parts of Argentina and Uruguay. Its life cycle is currently under study in France. Eggs are laid on the plant and it is thought that young larvae penetrate directly into the plant through the rachis or stipe. Larvae bore galleries inside the stipe, which may cross young developing leaflets (making holes in leaflets of the palm later) or completely cut the base of young palms. The last larval stage exits the plant and makes a cocoon. Adults are strong and rapid flyers. Damage caused by P. archon includes: leaf perforations, presence of sawdust on the stipes, presence of galleries, abnormal drying of palms, dieback of the tree. In order to help palm growers in France, a special coordination group was created to gather more information on the pest and try to find control methods. P. archon has been added onto a list of pests against which control is mandatory in the region concerned. Phytosanitary measures are still being discussed but the following ones could be envisaged: declaration of all palm imports (thus implying phytosanitary checks), implementation of a special system to trace palm tree material moving in France, compulsory notification of any suspect symptoms to the authorities, destruction or treatments of infested plants.
Note: during surveys done on P. archon, another Lepidopteran was found on Phoenix canariensis trees showing holes at the basis of rachis. It was identified as Pseudarenipses insularum (Lepidoptera: Pyralidae). This species is also reported as present in Spain (Almería, Alicante and Islas Canarias). However, the potential damage it may cause to palm trees remains to be evaluated.
Reynaud, P.; Chapin, E.; Hostachy, B.; Drescher, J.; Blanchon; F.; Vidal, C. (2002) Deux nouveaux papillons à l’assaut des palmiers de la Côte d’Azur. Paysandisia archon et Pseudarenipses insularum.
Phytoma – La Défense des Végétaux, no. 550, 18-21.