Red-necked Longhorn Beetle

The red-necked longhorn beetle is native to Asia and is a pest of the Prunus genus.

The red-necked longhorn beetle is not known to be in the UK but has been accidentally introduced to Germany and Italy. In 2008 a few individuals were found in wooden pallets in the UK but were caught before an outbreak could occur. The Prunus genus contains a lot of fruiting species such as plum, cherry, apricot and peach, meaning this pest is not only economically important but is also a threat to our native hedgerows.      

The beetle causes damage during its larval stage as it spends most of its life inside the wood of living prunus trees, making infestations difficult to spot. Imported products created from the host wood could also harbour living larvae if legal phytosanitary requirements have not been fully met. Female beetles prefer older trees as they have rougher bark with more crevices for egg laying. Hatched larvae tunnel into the tree where they disrupt and damage its nutrient transportation systems. Signs of the larvae and beetles include early leaf drop as well as discoloured, wilting and dying foliage together with dieback. Piles of frass (a mix of sawdust and excrement) around the base of the tree together with oval exit holes in the bark of 6-12mm are also indicative. The adult beetles are elongate, shiny, blue-black and typically 20mm-40mm in length, with long black antennae and a bright red pronotum (the area behind the head).  

For more information on the Red-necked longhorn beetle, see the resources below.