A Plio-Pleistocene moss assemblage from Store Koldewey, NE Greenland

A fossil assemblage from Store Koldewey (75°55^'-76°45'N, 18°27^'-19°10'W), deposited 1.8-2.6 million years ago, includes almost 50 moss taxa. Hamatocautis vernicosus (Mitt.) Hedenäs and possibly Hygrohypnum montanum (Lind.) Broth, have not been previously found in Greenland either as fossils or extant populations. Although many of the recovered fossil mosses are widespread species, there is a significant component of temperate species, or alpine in addition to temperate species, suggesting a considerably milder climate than today. The wetland taxa suggest relatively mineral-poor habitats, indicating an origin in the western part of the island, where the bedrock is acidic gneiss. The occurrence of many arctic or arctic-alpine mosses in North American deposits older than 3 to 4 million years indicates that these species evolved before the start of more intensive glaciations of the present Arctic and before the bulk of the arctic flora supposedly evolved.