Anatomical structure of pores in European species of genera Boletus s.str. and Butyriboletus (Boletaceae).

One of the characteristic features of European species of genera Boletus s.str. and Butyriboletus is a conspicuous development of their cheilocystidia covering their pores in youth. The development of this type of cheilocystidia is partly supported by the growth of hyphae of the hymenophoral trama under the cheilocystidia. This special arrangement of cheilocystidia is an important diagnostic character distinguishing European species of the above-mentioned genera from other groups of boletes in Boletaceae. The microscopical structure of this type of pores is described in detail. [ABSTRACT FROM AUTHOR]