1. Rhaponticum repens (L.) Hidalgo (syn.: Centaurea repens L., Acroptilon repens (L.) DC. ) (Russia, C-As.) – A very rare and usually ephemeral alien. First recorded in 1956 in the port of Antwerpen on a talus slope of a railway track (several specimens but locality destroyed in 1957; De Langhe 1976). Furthermore recorded in small number near a grain storage at the Amerikadok in the port of Antwerpen between 2000 and 2004; now gone.
Belgian collections of Rhaponticum repens are rather characteristic by their creeping habit (strongly rhizomatous perennial), pale pinkish to almost white corollas and very leafy, more or less whitish stems.
Rhaponticum repens was originally restricted to eastern Europe and Central-Asia. It is now widely naturalised and invasive beyond its native distribution range, for instance in North America and Australia. It was recently also discovered in Spain where it was overlooked for and confused with Centaurea jacea for many decades (López-Alvarado & al. (2011).
De Langhe J.E. (1976) Adventices nouvelles pour la flore belge. Bull. Soc. Roy. Bot. Belg. 109: 25-27.
López-Alvarado J. Crespo M.B., Garcia-Jacas N., Alonso M.A., Vilar L., Cristóbal J.C., Susanna A., Martínez-Flores F., Juan A. & Sáez L. (2011) First record of the alien pest Rhaponticum repens (Compositae) in the Iberian Peninsula. Collect. Bot. 30: 59-62. [available online at: http://collectaneabotanica.revistas.csic.es/index.php/collectaneabotanica/article/viewFile/185/187]
Weinert E. (1967) Acroptilon repens (L.) DC., ein Neophyt in Mitteldeutschland. Hercynia N. F. 4: 146-151.