Xylosandrus crassiusculus: new detections in Liguria (Northern Italy)
In Italy, Xylosandrus crassiusculus (Coleoptera: Scolytidae – EPPO Alert List) was first trapped in Toscana (near Pisa) in a mixed forest dominated by Pinus pinaster and Quercus cerris (Pennacchio et al., 2003). In 2007 and 2008, damage caused by X. crassiusculus was observed on Ceratonia siliqua (carob tree) in private and public gardens in Alassio municipality, Liguria region (see also EPPO RS 2009/054, 2010/031). Other observations were reported by local technical advisors in 2009, but concerned the same area. In June 2012, X. crassiusculus was still found in same province, but it was also detected in the Pietra Ligure municipality, 20 km away from the first observation site. The pest was again observed on C. siliqua in private gardens where it bores into branches and twigs causing foliage wilt and a general decline of plants. Frass, pushed out of galleries by the insect and forming compact cylinders, was observed on all infested trees. Some infested branches were collected and studied at the laboratory of CeRSAA. The adult insects found were then sent for determination to the University of Torino (DiVaPRA – Entomology) which confirmed the presence of X. crassiusculus. Since the initial report in Alassio in 2007, this is the first time that X. crassiusculus is reported from other areas in Liguria. The pest was only found on C. siliqua despite the presence of several other potential hosts growing in the same area, such as Diospyros kaki, Ficus carica, Malus domestica (apple), Prunus avium (cherry), P. domestica (plum), P. persica (peach). Nevertheless this report appears to confirm the establishment of X. crassiusculus, at least along the Ligurian coastal area.
Personal communication with Federico Tinivella, Andrea Minuto, CeRSAA, Italy, 2012.
Pennacchio F, Roversi PF, Francardi V, Gatti E (2003) Xylosandrus crassiusculus (Motschulsky) a bark beetle new to Europe (Coleoptera Scolytidae) Redia 86, 77-80 (abst.).