Iris pumila L. (SE-Eur., SW-As.) – A very rare and decreasing escape from cultivation. Formerly naturalized on old walls, especially in Wallonia (e.g. Olloy, Dourbes, Verviers) and still rarer in Flanders (e.g. Brugge). Much less cultivated nowadays and long believed to be extinct in Belgium (e.g. Lambinon 2005). It was last seen in 1960 in Olloy where it was known at least since 1888. However, Iris pumila was rediscovered in 2012 on top of an old wall at the castle of Waulsort in the valley of river Meuse. In this area it is apparently still firmly established and known from several localities.
Selected literature:
Koca F. (2003) Morpho-anatomical and karyological studies on Iris pumila (Iridaceae). Bocconea 16(2): 625-639. [available online at: http://147.163.105.223/bocconea/16-0625.pdf]
Kohlein F. (1979) Iris pumila L. Staudengarten 3: 16-18.
Lambinon J. (2005) La cinquième édition de la « Nouvelle Flore » de la Belgique et des régions voisines: commentaires taxonomiques, nomenclaturaux et chorologiques. Dumortiera 85-87: 1-94.
Luscombe E.G.B. (1973) Iris pumila Linnaeus: descriptive notes of its botanical characteristics including morphology, variability, the geographical range of its natural distribution and the like: a resume of available data: part 1. Iris Year Book 1972: 149-157.
Luscombe E.G.B. (1973) Iris pumila Linnaeus: descriptive notes of its botanical characteristics including morphology, variability, the geographical range of its natural distribution and the like: a resume of available data. Part 2. Iris Year Book 1973: 71-79.
Melko E. (1977) Numerical taxonomic studies on Iris pumila L. by cluster analysis. Acta Bot. Acad. Sci. Hung. 22(3-4): 403-414.
Melko E. (1977) Morphologische Untersuchungen an der Art Iris pumila L. (in Hungarian). Bot. Kozlem. 64(3): 155-164.
Melko E. (1978) Angaben zur Systematik und Verbreitung von Iris pumila L. in Hungarian). Bot. Kozlem. 65(1): 15-26.
Melko E. (1981) Iris classification on the basis of generative characteristics. Acta Bot. Acad. Sci. Hung. 27(1-2): 105-119.