Alkaline wing-nerved moss (Pterygoneurum kozlovii) assessment and status report: chapter 2


Executive Summary

Alkaline Wing-nerved Moss
Pterygoneurum Kozlovii

Species Information

Pterygoneurum kozlovii is one of four species of Pterygoneurum in North America. It is a rather inconspicuous moss that forms small to medium sized patches on soil along alkaline wetlands in dry environments. Its most distinctive features are the small flaps that are found on the upper mid-ribs of the leaves and the immersed spore sacs that do not have a lid for spore release. 



Globally, this moss is found in western North America, Europe, and western Asia. In Canada, it has been found in Saskatchewan and British Columbia. It is relatively widespread, but relatively uncommon, in south-central British Columbia.



This species is restricted to seasonally wet, alkaline soils in open, and dry areas of British Columbia. Eight of the known sites are undisturbed to relatively undisturbed, and eight are moderately to heavily disturbed. Most of the extant populations appear to be on provincially owned lands, in particular Crown lands, although ownership needs to be confirmed for some sites.



Pterygoneurum kozlovii is a small, acrocarpous moss that usually grows in small to medium sized patches or turfs along the edges of seasonally wet, alkaline areas. Sporophytes and spores are common in Canadian populations, and are probably important in maintaining local populations.


Population Sizes and Trends

Pterygoneurum kozlovii is uncommon to rare in most sites, and common and widespread in only three locations. Population trends are uncertain, although four may be declining. 


Limiting Factors and Threats

Impacts of grazing animals, urban development, road building, and human use of the habitat appear to be the main limiting factors and threats to Pterygoneurum kozlovii. Recent drought may also be a limiting factor.


Special Significance of the Species

Pterygoneurum kozlovii is restricted to Canada in North America. Although it is relatively widespread in southern British Columbia, it is usually not common. It is found in the endangered Purshia tridentata ecosystem in the south Okanagan Valley. The author has investigated the edges of more than 70% of the alkaline wetlands that have potential habitat for this species in British Columbia, and has confirmed the presence of this species at only 13 sites.


Existing Protection or Other Status Designations

No legislation, regulations, customs, or conditions protect Canadian populations of Pterygoneurum kozlovii. Globally this species is considered imperiled or rare, and it is Red-listed in British Columbia. It is considered endangered or rare in Mongolia.


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