Lentinellus herbarum, a rediscovered unclamped species

The fungus first described as Lentinus flabelliformis var. herbarum has been found fruiting on dead Epilobium angustifolium stalks at La Chaise-Dieu (France), the first record since its original diagnosis. The basidiospore characters, trama and hymenium structure indicate the species belongs Lentinellus sect. Omphalodei (Hericiales), but the absence of clamps is a remarkable character, new for this genus. The new combination L. herbarum comb. nov. (syn. Lentinus flabelliformis var. herbarum) is made and a neotype designated. A key to the eight European taxa of sect. Omphalodei is included.