Taxonomic revision of the Pinus mugo complex and P. rhaetica (P. mugo sylvestris) (Pinaceae)

The Pinus mugo complex is revised, and a new infraspecific classification of the species is proposed. The species is divided into two subspecies and an intermediate nothossp., viz. ssp. mugo , ssp. uncinata and nothossp. rotundata. P. mugo ssp. mugo is divided into f. mugo and f. applanata comb, et stat. nov. ( P. pumilio ) and P. mugo nothossp. rotundata into f. rotundata and f, mughioides comb. nov. The putative hybrid P. mugo × sylvestris found in mixed stands of the parents is named P. × rhaetica . A description of P. sylvestris and a key to P. mugo, P. sylvestris and P. × rhaetica is given.