Polyommatus coridon is an irregular resident and a vagrant. During the 1950s, there was a population for several years along a stretch of railway near Heerlen, in the province of Limburg. The seeds of its larval foodplant Hippocrepis comosa, which is virtually absent here, had been introduced by using soil from Germany for the construction of the embankment. Furthermore, over three hundred records exist for the species as a vagrant. However, the number of observations has dropped since the mid-sixties, and since 1990, only five individuals have been seen, the last one in 1995.
Wynhoff, I., Groenendijk, D., Swaay, C. van, Bosveld, M., Bos, F.
- Bos, F., M. Bosveld, D. Groenendijk, C. van Swaay & I. Wynhoff 2006. De dagvlinders van Nederland, verspreiding en bescherming. Nederlandse Fauna 7. De Vlinderstichting, Wageningen en Nationaal Natuurhistorisch Museum Naturalis, European Invertebrate Survey, Nederland.