Lichenen op de Portugees Israelietische Begraafplaats te Ouderkerk a/d Amstel

The ancient (since 1614) jewish cemetery at Ouderkerk a/d Amstel (serving Amsterdam) was visited upon request to assess the value of the lichen vegetation. It proved to be rather species-poor, but the vegetation was very well developed with Aspicilia calcarea, A. contorta, Caloplaca coronata, C. flavescens, Catillaria lenticularis, Lecanora albescens and Verrucaria nigrescens together completely covering most (hard limestone) graves. Lecanora horiza was common on vertical surfaces. The rarest species was Rinodina bischoffii, for which it is the second record from the country.