Panarctic Flora


342003 Calamagrostis purpurascens R. Br.

Geography: Asian (NE) - amphi-Beringian - North American - amphi-Atlantic (W).

Notes: Elven and Murray: Greene (1980, 1984) studied the variation in morphology and cytology in Calamagrostis in North America. He did not include C. sesquiflora or C. arctica in his treatment and he did not consider tetraploids vs. more high-ploids taxonomically. He found reasons to divide C. purpurascens into two varieties: a predominantly western var. purpurascens (including C. maltei and C. yukonensis) and an eastern var. laricina (including C. poluninii). The two taxa are distinguished by few characters: tufts without rhizomes in var. purpurascens vs. rhizomatous in var. laricina, and awns distinctly exserted 1-3 mm beyond tip of glumes vs. not or only slightly exserted up to 2 mm beyond tip of glumes. We have confirmed these differences when comparing northwestern North American with eastern Canadian and Greenlandic material. As they are major and parapatric geographical races, we prefer rank of subspecies in spite of the small morphological differences (Marr et al. 2007 did not recognize these races). The eastern race is known as octoploid from one report, whereas the predominantly western race is known with a range from tetraploid (also one from eastern North America) to dodecaploid. We follow Greene in not accepting C. maltei, C. yukonensis, or C. poluninii as recognizable taxa.

Higher Taxa