Orthilia secunda subsp. obtusata (Turcz.) Boecher

Gillespie, Lynn J., Saarela, Jeffery M., Sokoloff, Paul C. & Bull, Roger D., 2015, New vascular plant records for the Canadian Arctic Archipelago, PhytoKeys 52, pp. 23-79 : 47-48

Orthilia secunda subsp. obtusata (Turcz.) Boecher

Pyrola secunda var. obtusata Turcz.

Common names.

One-sided wintergreen, nodding wintergreen

Distribution.

Disjunct circumpolar (excluding Europe)

Comments.

This is the first collection of the species from the eastern CAA; previously it had been collected in the western Arctic Islands at two localities on Victoria Island ( Aiken et al. 2007), where we also collected it from a third locality, and one on Banks Island ( Porsild and Cody 1980; not mapped in Aiken et al. 2007). In the eastern North American Arctic, this species is known from western Greenland ( Böcher et al. 1968) and Ungava Bay, Quebec ( Porsild and Cody 1980), thus our collection fills in a distributional gap in the general area between these sites, extending the range to southern Baffin Island. Our collection on Baffin Island comes from a single population encountered along the Soper River. This small population was found growing abundantly in a wet snowbed community with Cassiope tetragona , Vaccinium uliginosum , and Salix reticulata . On Victoria Island, we found this species growing in a similar habitat: a wet sedge meadow formed by a drainage between two lakes, associated with Carex aquatilis var. minor , Eriophorum angustifolium , Dryas integrifolia , Salix reticulata , Salix glauca , and Pedicularis albolabiata ( Hultén) Kozhevn.

Elven et al. (2011) recognize this taxon at the species level as Orthilia obtusata (Turcz.) H. Hara, a circumpolar plant distinct from the mostly circumboreal Orthilia secunda (L.) House. Freeman (2009) treats North American material as widely variable, and synonymises subsp. obtusata under Orthilia secunda . As there are distinctions between the taxa, most pronounced in Eurasia, we follow Aiken et al. (2007), and treat the Arctic taxon as Orthilia secunda subsp. obtusata , an approach intermediate to those of Elven et al. (2011) and Freeman (2009).

Specimen examined.

Canada. Nunavut: Kitikmeot Region, Victoria Island, Johansen Bay, 18 km ENE of airstrip, Nakoyoktok River at outflow of large unnamed lake, 62°39'25"N, 110°42'30"W, 20-30 m, 18 July 2008, Gillespie, Saarela, Consaul & Bull 8036 (ALA, CAN-592359); Qikiqtaaluk Region, Baffin Island, Katannilik Territorial Park Reserve, Soper River, 18.5 km downstream (S) of its confluence with the Livingstone River, 2 km S of Emergency Cabin #8, W side of river, 62°59'28"N, 69°43'30"W, 67 m, 15 July 2012, Saarela, Gillespie, Sokoloff & Bull 2489 (CAN-601915).