A Range Extension for Carex sartwellii in Interior Alaska

Résumé

Our documentation of Sartwell’s Sedge, Carex sartwellii, on nine shrinking lakes during fieldwork in the central Yukon Flats, Alaska, represents a range extension for this species. Previously, its range extended as far northwest as Yukon, Canada, with a reported, but lost collection, from Alaska in 1895. Two earlier collections from the Yukon Flats have been verified; one was misidentified as Carex praegracilis until 2007. Carex sartwellii’s assumed absence from Alaska and Yukon flora, misidentification of an earlier collection, and the remoteness of the Yukon Flats may have contributed to the rarity of its collection. In Alaska this species is morphologically similar to C. praegracilis, but can be distinguished using traits of the perigynia, leaf sheaths, and the production of true vegetative culms.