Lichens from the Hudson Bay lowlands: Diversity in the southeastern peatlands of Wapusk National Park, Manitoba

Peatlands form an important component of the Northern Hemisphere. They provide substrate for lichen growth and are used by large mammals such as polar bears, caribou, and humans. This study provides the first annotated species list of lichens on the peatlands of Wapusk National Park, Manitoba. It also provides insight into the chemical and genetic diversity of members of Cladonia that dominate the peatlands. Ninety-three species of lichen-forming fungi are reported for the peatlands, fewer than that reported for the coastal beach ridges in Wapusk National Park. This study reports six species of cyanobacterial lichens and two species of Basidiomycete lichens, including two new occurrences for Manitoba, Leptogium intermedium (Arnold) Arnold and Lichenomphalia hudsoniana (H.S. Jenn.) Redhead, Lutzoni, Moncalvo, & Vilgalys. Both chemical diversity in the genus Cladonia and genetic diversity within the species, Cladoniaaarbuscula (Wallr.) Flotow, were lower than those of a comparable study in a more southerly location. The abundance of apothecia produced by crustose species on the peatlands suggests that crustose species were predominantly sexually reproducing. Foliose species showed production of both sexual and vegetative features, and the fruticose species were mainly vegetatively reproducing. The study raises questions on life history strategies, the influence of habitat on lichen chemistry, and genetic variation of lichen algae in northern environments.