Addition of Paysandisia archon to the EPPO Alert List
The EPPO Secretariat tried to find more data on Paysandisia archon but with little success: the only data it could find came from the Internet. Surprisingly, the same unusual insect has been found in Spain, also in one nursery importing palm trees from South America. Therefore, the EPPO Secretariat decided to add it to the EPPO Alert List, despite the lack of information.
Paysandisia archon (Lepidoptera: Castniidae) – a palm borer
Why: Paysandisia archon came to our attention because it has recently been introduced into France (near Hyères) and Spain (near Girona), where it caused damage to ornamental palm trees.
Where: P. archon originates from South America: Argentina and Uruguay. Found in France, in summer 2001 near Hyères. According to a French association of palm amateurs, numerous dead palm trees were observed in several nurseries. Adults were observed flying near Hyères, Six Fours and Ollioules. It is felt that the insect was introduced 4 years ago by various importers on Butia yatay and Trithrinax campestris from Argentina. In Spain, P. archon has been found in one nursery in Girona, Cataluña in 2000/2001 on Trachycarpus fortunei, Phoenix canariensis and Chamaerops humilis. It is felt that P. archon was introduced between 1985 and 1995 on palm trees from Argentina. In Girona, Trachycarpus fortunei was the most severely affected palm species.
On which plants: Many palm species, e.g.: Butia yatay, Chamaerops humulis, Latania, Phoenix canariensis, Trachycarpus fortunei, Trithrinax campestris, Washingtonia.
Damage: Larvae bore galleries within palm stipes, leading to serious damage, including plant death. In Girona, it has been observed that females lay eggs on palm stipe near the growing point. Young larvae bore into the stipe and make large galleries. Pupation takes place inside a cocoon made of plant fibres between palm petioles. Adults are beautiful butterflies, with a wingspan of 10 to 11 cm. Posterior wings are red with black and white maculas. It is probable that this species has a biannual life cycle, but more data is needed on the biology of this insect.
Dissemination: Natural dispersal can be ensured by flying adults. Over long distances, the pest has already showed its potential for spread, being introduced into two countries in Europe. Movements of infested plants can ensure long distance dissemination. Larvae are obviously very difficult to detect in palm trees due to their hidden mode of life.
Pathway: Plants for planting of Palmae from Argentina and Uruguay.
Possible risks: Palm trees are grown around the Mediterranean Basin. Apparently, only ornamental trees are concerned by P. archon, but more data is needed on the susceptibility of date palm trees (Phoenix dactylifera) to this insect as it is an important crop in certain parts of the EPPO region. Serious damage and plant mortality are reported in nurseries. Detection and control are difficult, as larvae cannot be seen nor reached easily within the stipe. Although more data is needed on the biology of P. archon and on its potential of establishment under Mediterranean climate, present experience shows that it can survive there for at least a few years.
EPPO RS 2002/012
Panel review date - Entry date 2002-01
Sources
INTERNET
ACER Jardines. Presencia en España de una nueva especie de lepidoptero que afecta a las palmeras. http://www.acer-jardines.com
Association des Amateurs de Palmiers. ‘Fous de Palmiers’ (Hyères) Palm warning. http://www.chez.com/palmiers/alertecastnia.php
Vivers Ter, S.A. (Nursery near Girona) Nueva plaga en palmáceas. http://www.v-ter.com/set2001.htm