Silene stricta L. (W-Medit.) – A rare and ephemeral alien. First recorded on waste land in Ensival in 1908. Discovered on an unloading quay for cereals in Turnhout in 1978. Seen on various occasions in 1997: waste ground near a paste mill in the port of Roeselare and unloading quays for cereals in the port of Gent and in Turnhout (Verloove & Vandenberghe 1998, as Silene muscipula). Perhaps most recently seen at the Samga grain mill in the port of Antwerpen in 2012.
Most Belgian records of Silene stricta have initially been confused with S. muscipula. Both species are, indeed, exceedingly alike. Silene stricta has a calyx with five wings but these are (especially in the herbarium!) closely appressed to the calyx and not very obvious.
Selected literature:
Henrard J.Th. (1918) Bijdrage tot de kennis der Nederlandsche adventiefflora. Nederl. Kruidk. Arch. 1918: 181-205.
Verloove F. & Vandenberghe C. (1998) Nieuwe en interessante voederadventieven voor de Belgische flora, hoofdzakelijk in 1997. Dumortiera 72: 18-36.