 Tricholoma pardinum , commonly known as spotted tricholoma , tiger tricholoma , tigertop , leopard knight , or dirty trich , is a gilled mushroom widely distributed across North America and Europe , as well as parts of Asia . It is generally found in beech woodland in summer and autumn . Two subspecies have been described from southern Europe . First officially described by Christiaan Hendrik Persoon in 1801 , Tricholoma pardinum has had a confusing taxonomic history that extends over two centuries . In 1762 , German naturalist Jacob Christian Schäffer described the species Agaricus tigrinus with an illustration corresponding to what is thought to be T. pardinum , and consequently , the name Tricholoma tigrinum has been used erroneously in some European field guides . 
