Old House Borer - Hylotrupes bajulus

    Alternative names
    House Longhorn

    This beetle is around 15 mm long and brown to black, sometimes appearing greyer because of a fine grey furriness on most of the upper surface. On the pronotum two conspicuously hairless tubercles are characteristic of the species.

    Identification difficulty
    Recording advice

    Unless identified by a recognised expert, a photo is required and the specimen should be examined with a microscope. In the comments box, state the key or ID method used and describe the size and identifying characters.


    Despite the common name Old House Borer, this wood boring species is most likely to attack more recently felled timber, maybe because the beetles are attracted to the higher resin content of wood harvested more recently than 10 years earlier.

    When to see it

    Adults are most active in the summer.

    Life History

    The life cycle from egg to egg typically takes two to ten years, depending on the type of wood, its age and quality, its moisture content, and also depending on environmental conditions such as temperature. Only the larvae feed on the wood. Larvae usually pupate just beneath the wood surface and emerge as an adult from the pupa in mid to late summer. Once the exoskeleton of the newly emerged adult beetle has hardened sufficiently the adults cut oval exit holes 6 to 10 mm in diameter, typically leaving coarse, powdery frass in the vicinity of the hole.

    UK Status

    Mainly recorded in the southeast of England with just a few scattered records from elsewhere in Britain.

    VC55 Status

    Rare in Leicestershire and Rutland, The Magna Park record of 2019 is thought to be the first for VC55.

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    Leicestershire & Rutland Map

    MAP KEY:

    Yellow squares = NBN records (all known data)
    Coloured circles = NatureSpot records: 2020+ | 2015-2019 | pre-2015

    UK Map