Maritime quillwort

Isoëtes beringgensis Komarov; I. echinospora Durieu subsp. maritima (L. Underwood) A. Löve; I. echinospora var. maritima (L. Underwood) A. A. Eaton; I. macounii A. A. Eaton

Plant usually aquatic, occasionally emergent. Rootstock nearly globose, 2-lobed. Leaves ± deciduous, bright green, pale toward base, spirally arranged, to 12 cm, pliant, gradually tapering toward tip. Velum covering less than 1/2 of sporangium. Sporangium wall ± brown-streaked. Megaspores whtie, 380--600 μm diam., echinate to short-cristate with stout blunt spines and crests; girdle densely echinate. Microspores gray to brown in mass, 30--40 μm, papillose. 2 n = 44.

Spores mature late summer. Lakes and streams; B.C.; Alaska, Wash.

Isoëtes maritima hybridizes with I. echinospora and I. occidentalis [ = I. truncata (A. A. Eaton) Clute].