Isoëtes echinospora


Bull. Soc. Bot. France 8:164. 1861.

Common names: Spiny-spored quillwort isoète à spores épineuses
Synonyms: Isoëtes braunii Durieu Isoëtes echinospospora subsp. muricata (Durieu) A. Löve & D. Löve Isoëtes echinospora var. boottii Engelmann Isoëtes echinospora var. braunii (Durieu) Engelmann Isoëtes echinospora var. muricata (Durieu) Engelmann Isoëtes muricata Isoëtes setacea subsp. muricata (Durieu) Holub
Treatment appears in FNA Volume 2.

Plants usually aquatic, occasionally emergent. Rootstock nearly globose, 2-lobed. Leaves ± deciduous, bright green to reddish green, pale toward base, spirally arranged, to 25(–40) cm, pliant, gradually tapering toward tip. Velum covering less than 1/2 of sporangium. Sporangium wall ± brown-streaked. Megaspores white, 400–550 μm diam., echinate with thin, sharp spines; girdle obscure. Microspores gray to light brown in mass, 20–30 μm, smooth to spinulose. 2n = 22.

Phenology: Spores mature in late summer.
Habitat: Emergent or in shallow, cool, oligotrophic water of slightly acidic lakes, ponds, and streams


V2 152-distribution-map.gif

Greenland, Alta., B.C., Man., N.B., Nfld. and Labr. (Nfld.), N.W.T., N.S., Nunavut, Ont., P.E.I., Que., Sask., Yukon, Alaska, Calif., Colo., Conn., Idaho, Maine, Mass., Mich., Minn., Mont., N.H., N.J., N.Y., Ohio, Oreg., Pa., R.I., Utah, Vt., Wash., Wis., circumboreal.


North American plants of Isoëtes echinospora, which bear stomata, have been called I. muricata or I. echinospora var. braunii to distinguish them from European plants of I. echinospora, which do not have stomata.

Isoëtes echinospora is a distinct species but has considerable variation, especially in size, color, and form of leaves. It is the most commonly encountered quillwort in oligotrophic, noncalcareous lakes and ponds of northeastern North America.

Isoëtes echinospora hybridizes with I. bolanderi; I. engelmannii [ = I. x eatonii Dodge (later synonym = I. x gravesii A. A. Eaton)]; I. lacustris [ = I. x hickeyi Taylor & Luebke]; I. maritima; I. riparia [ = I. x dodgei A. A. Eaton]; and I. tuckermanii.

Selected References


Lower Taxa

... more about "Isoëtes echinospora"
W. Carl Taylor +, Neil T. Luebke +, Donald M. Britton +, R. James Hickey +  and Daniel F. Brunton +
Durieu +
Spiny-spored quillwort +  and isoète à spores épineuses +
Greenland +, Alta. +, B.C. +, Man. +, N.B. +, Nfld. and Labr. (Nfld.) +, N.W.T. +, N.S. +, Nunavut +, Ont. +, P.E.I. +, Que. +, Sask. +, Yukon +, Alaska +, Calif. +, Colo. +, Conn. +, Idaho +, Maine +, Mass. +, Mich. +, Minn. +, Mont. +, N.H. +, N.J. +, N.Y. +, Ohio +, Oreg. +, Pa. +, R.I. +, Utah +, Vt. +, Wash. +, Wis. +  and circumboreal. +
Emergent or in shallow, cool, oligotrophic water of slightly acidic lakes, ponds, and streams +
Spores mature in late summer. +
Bull. Soc. Bot. France +
Isoëtes braunii +, Isoëtes echinospospora subsp. muricata +, Isoëtes echinospora var. boottii +, Isoëtes echinospora var. braunii +, Isoëtes echinospora var. muricata +, Isoëtes muricata +  and Isoëtes setacea subsp. muricata +
Isoëtes echinospora +
Isoëtes +
species +