Wingspan c. 10-13mm.
A variable species, which resembles certain other Elachista species, but shows a more incomplete inner fascia and a darker head.
It is distributed throughout much of Britain, although doesn't occur in the south-west and some eastern areas.
Adult moths fly between June and September, and the larvae, which mine the blades of sedges (Carex spp.), can be found from September, and then overwinter, reappearing in spring.