Antipodal mosses: VI. Stegonia latifolia (Musci, Pottiaceae) in the Antarctic

Stegonia latifolia (Schwaegr. in Schult.) Vent. ex Broth. is recorded from the Antarctic on the basis of the specimens collected from Signy Island, South Orkney Island and King George Island, South Shetland Islands. The Antarctic material is briefly described and illustrated and the world geographical distribution of this species is briefly reviewed and mapped. This is also the first well documented record of the genus Stegonia Vent. outside the Holarctic. It is suggested that S. lorentzii (C. Muell.) I. Hag. in I. Hag. & Printz from the Andes of Argentina, another species included in this genus, is conspecific with Saitoella peruviana (R. S. Williams) Menzel. A list of strictly bipolar moss species in the western hemisphere is reassessed and two species, Ditrichum heteromallum (Hedw.) Britt. and Tortella torluosa (Hedw.) Limpr., are excluded from it.