Xylosandrus (Reitter)

Garonna, Antonio P., Dole, Stephanie A., Saracino, Antonio, Mazzoleni, Stefano & Cristinzio, Gennaro, 2012, First record of the black twig borer Xylosandrus compactus (Eichhoff) (Coleoptera: Curculionidae, Scolytinae) from Europe, Zootaxa 3251, pp. 64-68 : 64

The genus Xylosandrus (Reitter)

The genus Xylosandrus belongs to the Xyleborini , a large and complex tribe containing more than 1,200 species of the weevil subfamily Scolytinae ( Coleoptera : Curculionidae ), which is comprised of 26 tribes containing approximately 225 genera and 6000 species worldwide ( Wood 2007). The genus has a widespread distribution primarily in tropical, but also in temperate regions of the world. In their catalogue of the Scolytinae , Bright & Skidmore (1997) listed 54 species of Xylosandrus . Phylogenetic analyses of the species formerly included in Xylosandrus carried out by Dole et al. (2010) and Dole & Cognato (2010), provided new species descriptions, as well as new generic and specific combinations, reducing the number of species ascribed to the genus to 39. In these main revisions, species that are morphologically consistent with the strict definition of the genus ( Xylosandrus spp. are easily recognized by the widely separated procoxae), were included in the Xylosandrus “ sensu stricto ” clade. This clade included three economically important species: X. compactus (Eichhoff) , X. germanus (Blandford) and X. morigerus (Blandford) , the type species of the genus.

Several species from the tribe Xyleborini are important pests of ornamentals and forest species worldwide. In the few past decades, establishment of exotic species has steadily increased in Europe and the trend is expected to be further enhanced by global trade ( Roques et al. 2009; Kirkendall & Faccoli 2010; Sauvard et al. 2010). As recently discovered, certain symbiotic fungi may be very pathogenic on novel hosts in non-native ranges with dramatic consequences at the landscape level ( Fraedrich et al. 2008). Invasive fungus-associated woodborers increasingly emerge as a new and currently uncontrollable threat to forest and ornamental species in temperate regions ( Hulcr & Dunn 2011). Xylosandrus compactus represents the third species of this genus established in Italy in recent years, after X. germanus ( Zandigiacomo et al. 1998) and X. crassiusculus (Motschulsky) ( Pennacchio et al. 2004) ; the fourth species in Europe, X. morigerus , regularly occurs in European greenhouses (Kirkendall & Faccoli 2010).