An endangered Red Data Book species, until recently known only from a single site in Dorset, where it was discovered in 1996; also recorded occasionally as a migrant in south-eastern England, with six individuals between 1966 and 2006, from Kent, Sussex, Essex and Suffolk. On the Isle of Wight, the species was discovered new to Britain in Freshwater Marsh in 1945, but was lost to the county when the marsh was drained and burnt in 1952. Two individuals, thought at the time to be possible migrants, were recorded on the Isle of Wight at Totland in 2007 and Afton Marsh in 2011; but three subsequent records in the same area from 2012 to 2015 raise the very strong possibility that the island has been re-colonised, either from migration from the continent or from the Dorset site. Not recorded from Hampshire to date. Wingspan 31-34 mm. Differs from small examples of Large Wainscot Rhizedra lutosa
by the dark fuscous hindwing. Larva feeds on Lesser Pond-sedge, over-wintering as an egg.