In the type area of the Maastrichtian Stage (northeast Belgium, southeast Netherlands), two species of the rare hemiasterid echinoid genus Leymeriaster were known to date. Here we describe a third, L. campestris sp. nov., from the so-called ‘Laagje van Müller’ (Gemmenich Member, Vaals Formation) at Vaals-Eschberg, southern Limburg (the Netherlands), which is of early Campanian age. It differs from its late Maastrichtian congeners in the area, L. maestrichtensis and L. eluvialis, in that the pore pairs in the frontal groove of ambulacrum III are not in small depressions and the adjacent interambulacral margins are not thickened, raised and/or overhanging. It differs from L. maestrichtensis by the lack of a clear notch in the ambitus in ambulacrum III, and from L. eluvialis in the presence of a distinctly longer groove in ambulacrum III. Leymeriaster campestris sp. nov. is the first undoubted species of Campanian Leymeriaster known from northwest Europe.
