Pohlia wahlenbergii A. L. Andrews

Pohlia wahlenbergii (F.Weber & D.Mohr) A.L.Andrews

SPECIMENS EXAMINED. — Antarctica. West Antarctic Peninsula, Graham Coast, Wilhelm Archipelago, Argentine Islands, Galindez Island, Dongon Tower, 65°14’50.14”S, 64°14’40.24”W, in the tall moss turf subformation, 15.III.2014, Parnikoza 172/14 (KRAM [B-257790]); same locality, in the tall moss turf subformation, 24.II.2016, Parnikoza 281/16 (KRAM [B-257899]).

Sparse material of Pohlia wahlenbergii was collected twice from the same locality in 2014 and 2016 in a site occupied by the tall moss turf subformation in which it was associated with Polytrichum strictum, Polytrichastrum alpinum, Chorisodontium aciphyllum, Andreaea regularis, Pohlia nutans, Barbilophozia hatcheri, Cephaloziella varians (Gottsche) Steph. and Lophozia cf. groenlandica (Nees) Macoun.

Pohlia wahlenbergii is one of the rarest species of moss in the Antarctic and, interestingly, it has not yet been recorded from the mainland of the Antarctic. It was found only on the two islands in the South Shetland Islands archipelago (Ochyra et al. 2008a) (Fig. 7). The rarity of this species in the maritime Antarctic is surprising given its frequent occurrence on subantarctic South Georgia (Clarke 1973). It is very rare on King George Island (Ochyra 1998a), although in recent decades it appears to have spread on the island and in 2018 the species was found at some additional stations on newly formed moraines on recently deglaciated terrain (Wierzgoń, personal observations). It is more frequent on the volcanic Deception Island but it usually grows as an admixture in tufts of other moss species in geothermal habitats (Lewis Smith 2005a, b). The present discovery of P.wahlenbergii on Galindez Island in the Argentine Islands represents a significant exten-sion of its geographical range to the Graham Coast region and the shifting of the southern limit of its range to latitude 65°14’50.14”S approximately 250 kilometres south of the population recorded on Deception Island (Fig. 7).

Pohlia wahlenbergii is a bipolar species with some intermediate altimontane stations in the American Cordillera from southern Mexico to Bolivia. Interestingly, it is unknown from the Palaeotropics except for one unspecified record from Mauritius in the South Indian Ocean(O’Shea2003).In the south-temperate zone in the Southern Hemisphere is has a panholantarctic geographical range from Patagonia through the Southern Ocean islands to southern Australia and New Zealand (Ochyra et al. 2008a).