Last modified: Feb. 22, 2021, 11:55 a.m.
A rare species in Belgium. It was first observed in 1986 at Niel (AN).
This moth has a wingspan of 9–12 mm and is well recognisable due to the large white eye-caps and the white wings. Also with the dark brown spot halfway the inner margin of the forewings, which merge into one large dot when the moth is at rest. The related species O. salaciella lacks this spot.
The biology of this species is insufficiently known. The larva makes a long (ca. 20 cm) but inconspicuous mine in the bark of the stem of Lycopus europeus. In literature, this species was often erroneus associated with Caltha palustris.
The adults have been observed from early June till mid August.
The caterpillar of this species lives in Lycopus europeus. The mentions in literature of Caltha palustris are incorrect.
Occurs in swampy areas where the host plant can be found.