Old House Borer

Old House Borer - Hylotrupes bajulus

Alternative names
House Longhorn
Description

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.

Habitat

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.

Leicestershire & Rutland Map

MAP KEY:

Yellow squares = NBN records (all known data)
Coloured circles = NatureSpot records: 2025+ | 2020-2024 | pre-2020

UK Map

Additional images

No additional images available for this species.

All NatureSpot records