Endangered (proposed as a future Red Data Book species) in marshes and on river-banks in the Norfolk Broads and in marshes near the sea in Suffolk; recently also recorded from Co. Durham (MBGBI Vol 3), a priority species under the UK Biodiversity Action Plan. Unlikely to be recorded in Hampshire or on the Isle of Wight. Wingspan 12-13.5 mm. Like many of the Coleophora, imagines are virtually impossible to identify without recourse to dissection, and the larvae, which live in cases of characteristic form and which can sometimes be found on the foodplant, may be easier to identify by comparison against a reference collection. Larva feeds within seedpods of Water Dock, living within a movable case.