Black-spotted longhorn beetle

A black-spotted longhorn beetle resting on a leaf

Black-spotted longhorn beetle © Brian Eversham

A black-spotted longhorn beetle clinging to a leaf

Black-spotted longhorn beetle © Tom Hibbert

A black-spotted longhorn beetle perched on a woman's finger

Black-spotted longhorn beetle © Tom Hibbert

Black-spotted longhorn beetle

Scientific name: Rhagium mordax
These bulky beetles can sometimes be found on flowers in woodland rides or along hedgerows.

Species information

Statistics

Length: 13-23 mm

Conservation status

Common

When to see

April to August

About

The black-spotted longhorn beetle is found throughout most of the UK. They're usually seen in woodlands, or along hedgerows. The adult beetles often visit flowers to feed on nectar and pollen, particularly hawthorns and umbellifers. Female beetles lay their eggs on fallen dead wood, old stumps, or decaying trees. The larvae live beneath the bark, feeding on rotting wood. They can spend two or three years in this stage, before creating a little chamber of wood fibre in which to pupate. They pupate in late summer or early autumn, but the adults stay within their pupal chamber until spring.

How to identify

A mottled yellowish-brown and black beetle. It has two large black spots on its wing cases, with a pale band either side of each spot. The antennae are relatively short for a longhorn beetle.

Distribution

Widespread in England and Wales, though more patchily distributed in East Anglia. Locally distributed across Scotland and in Northern Ireland. Absent from the Isle of Man.

Did you know?

The larvae of this beetle contain antifreeze proteins that help them survive cold winters.