A small beetle (2.5 to 3.3 mm) it is dark blue, sometimes greenish, and very occasionally bronze.

Associated with plants of the Brassicaceae family, the adults are found on the leaves, but the larvae are leaf- and stem-miners.

All year round.

Overwinters as an adult in moss and grass tussocks.

Widespread and fairly frequent in Britain.

Occasional in Leicestershire and Rutland. There were a total of 18 VC55 records for this species up to March 2015.

Very similar to Psylliodes laticollis.