Homalotheciella subcapillata (Hedw.) Broth., a new moss species to Canada from old broadleaved forests of Nova Scotia

We report Homalotheciella subcapillata (Hedw.) Broth. for the first time in Nova Scotia, found in the western-most part of the province. Upon examination of a previously reported collection of this species from Saskatchewan, we determined that the previous collection was misidentified and conclude that our collections represent the first records of this species for Canada. The moss was found to grow only on old beech (Fagus grandifolia Ehrh.) trees in mature to old growth mixed broadleaved forests. The species has likely been present in Nova Scotia for many decades but was not previously detected due to low search effort. Given the apparent rarity and substrate specificity, the decline of its host tree, and the fact that it is threatened or vulnerable in the USA, we recommend that steps be taken to conserve this species and its habitats in Nova Scotia. Keywords: arboreal, Brachytheciaceae, bryophyte, epiphyte, moss