030102-03 The Isoëtes echinospora aggregate I. echinospora, I. muricata
Geography: Disjunct circumboreal.
Notes: Taylor et al. (1993) included both Eurasian and North American plants in one species under the European name Isoëtes echinospora, and they referred only one differential character: absence vs. presence of stomata. Other authors have accepted two species, the Eurasian I. echinospora and the American I. muricata, and have reported additional differential characters. We accept two species.
Löve (1970a) assigned the Icelandic plants to I. muricata. This was probably done, in this case and several others, to strengthen the impression of a significant American element in the Icelandic flora, mostly without sufficient support in the material (see notes to Cakile maritima and Leymus mollis for two of the more striking cases). Löve's opinion has been followed by some other authors, but Snogerup and Snogerup (2000) with confidence assigned the Icelandic plants to I. echinospora.
Higher Taxa
- Isoëtes [0301,genus]