Bryophytes of the Red River Gorge of Kentucky: floristics and phytogeography

The bryoflora of the Red River Gorge region, on the western escarpment of the Cumberland Plateau, is rich and geographically diverse. The 264 taxa include 179 mosses (174 species and 5 varieties) and 85 hepatic species. Most Red River taxa (about 80%) are more or less widely distributed in the northern hemisphere and about half range south to the Gulf Coast in North America. These remarkably broad distributions (compared to those of vascular plants) are similar to those for the North America bryoflora as a whole. At Red River, northern species, rare species, and hepatics are favored by the numerous caves and ravines carved from the hard Pennsylvanian sandstone-conglomerate and from Mississippian limestone. Rare species include Gymnostomum angustifolium, Hygrohypnum closteri, and Scopelophila cataractae. Examples of relict or disjunctive taxa found in caves are Bryoxiphium norvegicum, Hookeria acutifolia, Brothera leana, Diphyscium cumberlandianum, Rhabdoweisia crispata, Syrrhopodon texanus, Trichostomum tenuirostre, and Plagiochila sullivantii.