Oenanthe pimpinelloides L. (Beverneltorkruid): indigeniteit en onderscheidbaarheid

Oenanthe pimpinelloides is a Mediterranean-Atlantic species, outside of the Mediterranean regio known from W. and C. France, the South of England and Wales, W.-Ireland, as well as some scattered localities in W. Flanders and the Southern half of the Netherlands. Hitherto, the localities in the Netherlands have been considered adventitious occurrence. Thanks to a critical reappraisal it is likely, however, that the specimens collected in 1914-1917 on grassland along the small river Linge near Gorinchem belonged to an indigeneous population. In 1998-’99, a population of the species was observed and studied near the river Meuse in North-Brabant, in a pasture to be assigned to the community Arrhenatheretum elatioris. In Belgium and France O. pimpinelloides occurs in the same or a similar community. It seems likely, therefore, that in the Netherlands O. pimpinelloides is an indigenous species, reaching here the Northern limit of its area, and perhaps gradually enlarging it.