Xylosandrus compactus (Eichhoff)

Barnouin, Thomas, Soldati, Fabien, Roques, Alain, Faccoli, Massimo, Kirkendall, Lawrence R., Mouttet, Raphaëlle, Daubree, Jean-Baptiste & Noblecourt, Thierry, 2020, Bark beetlesand pinhole borers recently ornewly introduced toFrance (Coleoptera Curculionidae, Scolytinae and Platypodinae), Zootaxa 4877 (1), pp. 51-74 : 61-64

- Xylosandrus compactus (Eichhoff)

( Figs. 3C, 3D )

Distribution. Native to Asia, X. compactus is today a sub-cosmopolitan species distributed in Southeast Asia, Africa, Oceania, the Americas and Europe ( Wood & Bright 1992). In Europe it was detected for the first time in 2011 in Italy ( Garonna et al. 2012) where it quickly spread in almost all Tyrrhenian regions and Sicily; in 2015 reached southern France where established in parks and gardens ( Chapin et al. 2016). To date, its distribution in France extends on a fringe of the Mediterranean coast from Nice to Bormes-les-Mimosas, and an expansion toward West is highly probable in the next future.

Literature records: ALPES-MARITIMES – Antibes, Cap d’Antibes, 2015 ( Chapin et al. 2016); Saint-JeanCap-Ferrat, 2015 ( Chapin et al. 2016); VAR – Saint-Tropez, 2015 ( Chapin et al. 2016).

New records: ALPES-MARITIMES – Antibes , Garoupe Forest, traps baited with ethanol 100%, (-) α-pinene, and a pheromonal blend for longhorn beetles, from 25.VI. to 19.IX.2018, 37 ind., URZF leg.; Antibes, Villa Thuret, traps baited with ethanol 100%, (-) α-pinene, and a pheromonal blend for longhorn beetles, 10 ind. from 06.VIII. to 30.X.2017 & 27 ind. from 25.VI. to 19.IX.2018, URZF leg.; Cannes, Sainte- Marguerite island, interception traps baited with ethanol 100%, (-) α-pinene, and a pheromone blend for longhorn beetles, from 24.V. to 27.IX.2019, 13 ind., URZF leg.; Cap d’Ail, traps baited with ethanol 100%, (-) α-pinene, and a pheromonal blend for long-horn beetles, from 06.VIII. to 27.VIII.2018, 1 ind., URZF leg.; Nice, Mont Boron, bottle traps, from 06.VIII. to 30.X.2018, 12 ind., DSF leg.; ibidem, interception traps baited with ethanol 100%, (-) α-pinene, and a pheromone blend for longhorn beetles, from 06.VIII. to 17.IX.2018, 32 ind., URZF leg.; Théoule-sur-Mer, caught on Carob tree, 02.XII.2016, 120 ind., S. Pionnat leg.; Villeneuve-Loubet, traps baited with ethanol 100%, (-) α-pinene, and a pheromone blend for longhorn beetles, from 16.VII. to 27.VIII.2018, 3 ind., URZF leg.; ibidem, caught on Laurel, 24.IV.2018, 6 ind., DSF leg.; VAR – Bormes-les-Mimosas, caught on Laurel, 21.XI.2018, 3 ind., DSF leg.; Bormes-les-Mimosas, Chateau-Léoube, interception traps baited with ethanol 100%, (-) α-pinene, and a pheromone blend for longhorn beetles, from 24.V. to 27.IX.2019, 14 ind., URZF leg.; Saint-Raphaël, interception traps baited with ethanol 100%, (-) α-pinene, and a pheromone blend for longhorn beetles, from 30.VII. to 30.VIII.2019, 1 ind., URZF leg.; Saint-Tropez, the Salins, traps baited with ethanol 20%, from 27.IX. to 19.X.2017, 1 ind., DSF leg .

Biology and ecology. X. compactus is a highly polyphagous species recorded from more than 220 host plants ( Chapin et al. 2016). In France, it is already reported to breed on more than a dozen species, mainly ornamental shrubs, with a clear preference, as in Italy, for laurel ( Laurus nobilis L.). X. compactus is an ambrosia beetle infesting twigs and small-diameter branches (<2 cm) where females bore into the pith, although infestations of large trees may also occur. It is one of the few ambrosia beetles that infests healthy plants.

Damage and infestation risk. In tropical regions and in areas of recent introduction this species causes damage to host plants of major economic interest such as avocado ( Persea americana Mill. ) or coffee ( Coffea ) ( Garonna et al. 2012). Many other species of economic, ecological and ornamental importance can also be infested. Damage caused by this ambrosia beetle is mainly due to the female activity when boring egg tunnels inside the wood ( Garonna et al. 2012; Chapin et al. 2016). However, X. compactus is also associated with phytopathogenic fungi that could play a major role in tree dieback ( Vannini et al. 2017). In France, this species causes a quick leaf desiccation associated to a progressive drying of the affected stems of the infested laurel ( Chapin et al. 2016). Repeated attacks reduce the crown volume leading to physiologically weakened plants. In France, X. compactus mainly affects ornamental trees, but it could eventually become problematic in scrubland areas, as already recorded in Italy (Vanini et al. 2017).

Figures

FIGURE 3. Cryphalus dilutus Eichhoff (1.8 mm).A. dorsal view; B. lateral view. Xylosandrus compactus (Eichhoff) (1.7 mm). C. dorsal view; D. lateral view. Xylosandrus crassiusculus (Motschulsky) (2.6 mm). E. dorsal view; F. lateral view. Length of specimens in brackets. (Photos: Fabien Soldati & Thomas Barnouin).