Abstract
A new species of Ulota D. Mohr, U. larrainii, is described from the Aysén Region, southern Chile. The characters that discriminate the new moss are the prostrate habit, leaves not crisped, marginal cells of the leaf base differentiated in 1(2) rows, vaginula hairy, exostome of 8 pairs of orange, recurved teeth, endostome of 16 broad and hyaline segments, and large, multicellular spores. The new moss is illustrated and compared with similar taxa. In addition, the presence of multicellular spores in the genus Ulota is summarized and evaluated from an updated list of currently accepted species. Finally, the distribution, species richness and levels of endemism in the different regions where Ulota taxa occur are summarised and discussed with the help of a world map.