Biatora britannica sp nov and the occurrence of Biatora efflorescens in the British Isles

Biatora britannica sp. nov. is described from Wales. The species is the sor ediate sister taxon of the Madeiran Biatora hertelii. The close relationshi p is supported by the presence of the hymenial pigment Hertelii-green, whic h is hitherto known only from these two species. Molecular data from the nu clear ITS-region of 14 Biatora-species renders further support for the dose relationship of both species. Sterile, sorediate material from the British Isles earlier referred to B. efflorescens may in fact belong to B. britann ica. (C) 2001 Thr British Lichen Society.