Since publication of the distribution map of Mibora minima in the Atlas of the Netherlands Flora¹, several new localities of this rare species have been added to the ones previously known. Some of them are from the coastal dunes, where M. minima is growing in (semi-)natural environments, and one is from a former railroad-yard in the south of the province of Limburg. Thusfar the main localities appeared to be associated with tree nurseries. The opinion that the species was introduced into the Netherlands from nurseries abroad, seems to be incorrect, also, because the first record in the Netherlands, from 1825, is from a dune area. On account of ecological and distributional data of M. mibora from other Western European countries, it is concluded that the species is spreading naturally along the Atlantic seacoasts in dunal habitats, so that M. minima may well have reached the Netherlands without human interference.