Cryptogramma stelleri (S.G. Gmel.) Prantl

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 : 28

Cryptogramma stelleri (S.G. Gmel.) Prantl Fig. 2

Common name.

Steller’s rockbrake

Distribution.

Disjunct circumboreal (absent from Greenland and Europe)

Comments.

This is the first record of the species, genus and family from the CAA and for Nunavut. The genus is easily distinguished from other fern genera in the Arctic Islands by its dimorphic fronds. We discovered one small population on a southeast facing cliff by Fundo Lake on the outskirts of Kimmirut. Plants were small with sterile fronds 3-5(7) cm long and fertile fronds 4-8 cm long, and were growing with moss in horizontal fractures in grey marble.

Uncommon and with a scattered and disjunct distribution, Cryptogramma stelleri is found in North America primarily in the western montane boreal and eastern boreal zones ( Alverson 1993). It is listed in North America as apparently secure only in Ontario and Quebec, vulnerable to critically imperilled in all other provinces, and vulnerable to possibly extirpated in all states where it occurs and is ranked ( NatureServe 2014). Typical habitat in North America is considered to be crevices and rock ledges on calcareous cliffs in boreal habitats ( Alverson 1993). Absent from most of the Northwest Territories, Porsild and Cody (1980) recorded it as rare on moist shale slopes in the Richardson and Mackenzie mountains. In northern Quebec it occurs in several small isolated populations mostly in coastal areas near treeline, in cracks on moist shady calcareous cliffs or sometimes on granitic rock in moist, low acid soils on ledges and overhangs ( Dignard 2013). Three nearby sites on rocky escarpments near Kangiqsujuaq on the northern Quebec coast occur well within the Arctic (ca. 61°36'N). Our collection from 62°50'44"N on nearby Baffin Island represents a new northern limit for eastern North America. Low spore production, limited dispersal ability, and restricted habitat preference are thought to contribute to its rarity and scattered distribution ( Peck et al. 1990, Dignard 2013), and also suggests that this diminutive fern may simply have been overlooked in the past, rather than representing a recent introduction.

Specimens examined.

Canada. Nunavut: Qikiqtaaluk Region, Baffin Island, Kimmirut, W end of Fundo Lake, ca. 2 km W of hamlet, 62°50'44"N, 69°54'6"W, 40 m, 22 July 2012, Saarela, Gillespie, Sokoloff & Bull 2774 (ALA, CAN-601315).