Vascular plant biodiversity of the lower Coppermine River valley and vicinity (Nunavut, Canada): an annotated checklist of an Arctic flora

Abstract

The Coppermine River in western Nunavut is one of Canada’s great Arctic rivers, yet its vascular plant flora is poorly known. Here, we report the results of a floristic inventory of the lower Coppermine River valley and vicinity, including Kugluk (Bloody Falls) Territorial Park and the hamlet of Kugluktuk. The study area is approximately 1,200 km2, extending from the forest-tundra south of the treeline to the Arctic coast. Vascular plant floristic data are based on a review of all previous collections from the area and more than 1,200 new collections made in 2014. Results are presented in an annotated checklist, including citation of all specimens examined, comments on taxonomy and distribution, and photographs for a subset of taxa. The vascular plant flora comprises 300 species (311 taxa), a 36.6% increase from the 190 species documented by previous collections made in the area over the last century, and is considerably more diverse than other local floras on mainland Nunavut. We document 207 taxa for Kugluk (Bloody Falls) Territorial Park, an important protected area for plants on mainland Nunavut. A total of 190 taxa are newly recorded for the study area. Of these, 14 taxa (13 species and one additional variety) are newly recorded for Nunavut (Allium schoenoprasum,Carex capitata,Draba lonchocarpa,Eremogone capillarissubsp.capillaris,Sabulina elegans,Eleocharis quinqueflora,Epilobiumcf.anagallidifolium,Botrychium neolunaria,Botrychium tunux,Festuca altaica,Polygonum aviculare,Salix ovalifoliavar.arctolitoralis,Salix ovalifoliavar.ovalifoliaandStuckenia pectinata), seven species are newly recorded for mainland Nunavut (Carex gynocrates,Carex livida,Cryptogramma stelleri,Draba simmonsii,Festuca viviparoideasubsp.viviparoidea,Juncus alpinoarticulatussubsp.americanusandSalix pseudomyrsinites) and 56 range extensions are reported. ThepsbA-trnHandrbcLDNA sequence data were used to help identify the threeBotrychiumtaxa recorded in the study area. Three new combinations are proposed:Petasites frigidussubsp.sagittatus(Banks ex Pursh) Saarela,Carex petricosasubsp.misandroides(Fernald) Saarela andCarex simpliciusculasubsp.subholarctica(T. V. Egorova) Saarela.