Poronia punctata (L.: Fr.) Rabenh. (Xylariales, Ascomycota) in Poland: a threatened, rare, or overlooked species?

Poronia punctata is regarded as a threatened, rare coprophilous fungus species, especially in Europe. Lately, the fungus has been noted again in Poland after a century of absence. Micro- and macrotraits of P. punctata have been given on the basis of specimens from two collections: the first, contemporary one, found in the field in 2010, and the second and most probably oldest Polish one dating back to the years 1819–1845, from the collections of prof. Michał Szubert, found by us in the Herbarium of the University of Warsaw. The distribution of P. punctata localities within the present boundaries of Poland is presented. The occurrence conditions of P. punctata in Poland, especially the new locality, are characterized. Possible reasons why the species has not been noted within 1905–2009 in Poland are indicated. The threat status of the species according to the IUCN criteria is assessed and the threat category VU is proposed