Euphorbia epithymoides L. (syn.: E. polychroma A. Kerner) (S and E-Eur.) – A very rare escape from cultivation, sometimes temporarily persisting. Discovered near a military cemetery in Thuin in 1937 and still present in 1943. In 1964 also observed in Rochefort, without further details. Most recently seen from discarded garden waste in Lommel in 2012.