GENUS PHASCUM (POTTIACEAE) ON THE IBERIAN PENINSULA

A taxonomic study of the genus Phascum (Pottiaceae) in the Iberian Peninsula has been made. Specimens from European herbaria have been studied for the Phascum cuspidatum Hedw.-group, and those from Spanish herbaria for the other taxa. Two subspecies of P. cuspidatum are considered: the subspecies cuspidatum, which seems not to have a soil preference, and includes four varieties (var. cuspidatum, var. piliferum (Schreb. ex Hedw.) Hook. & Tayl., var. schreberianum (Dicks.) Brid. and var. retortifolium var. nova) and the subspecies papillosum (Lindb.) stat. nov. growing largely on acidic soils. Phascum vlassovii Laz. has been discovered in some Spanish localities; until now it was only known from Asia and Canada. Phascum piptocarpum Dur. & Mont., another new species for the European continent, is also found in the southeast of Spain. It has previously been known only from the type locality in Algeria (northern Africa). A recently described species, P. longipes Guerra, Martinez & Ros is also included, as well as P. cuynetii Biz. & Pierr., restricted to the southeast and east of Spain, and P. curvicolle Ehrh. ex Hedw. and P. floerkeanum Web. & Mohr, frequent in the studied area.