Isoetes
Isoetes riparia
EOL Text
Degree of Threat: Medium
| License | http://creativecommons.org/licenses/by-nc/3.0/ |
| Rights holder/Author | NatureServe |
| Source | http://explorer.natureserve.org/servlet/NatureServe?searchName=Isoetes+riparia |
Megaspore morphology, electrophoretic profiles of leaf enzymes, and chromosome number provide evidence that Isoëtes riparia is an allotetraploid, formed by chromosome doubling in I. x eatonii, the primary diploid hybrid between I. echinospora and I. engelmanii. The considerable variation in leaf and spore morphology possibly results from multiple allotetraploid origins.
Isoëtes riparia hybridizes with I. echinospora [ = I. x dodgei A. A. Eaton]; I. engelmannii [ = I. x brittonii Brunton & W. C. Taylor]; I. lacustris [ = I. x jeffreyi D. M. Britton & Brunton); and I. tuckermanii.
| License | http://creativecommons.org/licenses/by-nc-sa/3.0/ |
| Rights holder/Author | eFloras.org Copyright © Missouri Botanical Garden |
| Source | http://www.efloras.org/florataxon.aspx?flora_id=1&taxon_id=250076855 |
Comments: Allotetraploid of multiple origins from chromosome doubling of Isoetes x eatonii, the diploid hybrid of Isoetes echinospora and I. engelmannii (FNA, 1993).
| License | http://creativecommons.org/licenses/by-nc/3.0/ |
| Rights holder/Author | NatureServe |
| Source | http://explorer.natureserve.org/servlet/NatureServe?searchName=Isoetes+riparia |
Type collection for Isoetes saccharata var. amesii A.A. Eaton
Catalog Number: US 510832
Collection: Smithsonian Institution, National Museum of Natural History, Department of Botany
Preparation: Pressed specimen
Collector(s): A. A. Eaton
Year Collected: 1903
Locality: Massachusetts, United States, North America
- Type collection: Eaton, A. A. 1903. Rhodora. 5: 5.
| License | http://creativecommons.org/licenses/by/3.0/ |
| Rights holder/Author | This image was obtained from the Smithsonian Institution. Unless otherwise noted, this image or its contents may be protected by international copyright laws. |
| Source | http://collections.mnh.si.edu/search/botany/?irn=2140976 |
Canada
Origin: Native
Regularity: Regularly occurring
Currently: Present
Confidence: Confident
United States
Origin: Native
Regularity: Regularly occurring
Currently: Present
Confidence: Confident
| License | http://creativecommons.org/licenses/by-nc/3.0/ |
| Rights holder/Author | NatureServe |
| Source | http://explorer.natureserve.org/servlet/NatureServe?searchName=Isoetes+riparia |
Global Range: This aquatic plant ranges from southern Quebec and Ontario, south through eastern New York and western New England, down to the coastal plain of North Carolina.
| License | http://creativecommons.org/licenses/by-nc/3.0/ |
| Rights holder/Author | NatureServe |
| Source | http://explorer.natureserve.org/servlet/NatureServe?searchName=Isoetes+riparia |
Plants usually aquatic, occasionally emergent. Rootstock nearly globose, 2-lobed. Leaves evergreen, bright green, pale toward base, spirally arranged, often twisted, to 35(--50) cm, pliant, gradually tapering to tip. Velum covering less than 1/2 of sporangium. Sporangium wall brown-streaked to completely brown. Megaspores white, 450-650 μm diam., cristate with isolated and branching, lamellate ridges; girdle obscure. Microspores gray to light brown in mass, 30--40 μm, tuberculate. 2n = 44.
| License | http://creativecommons.org/licenses/by-nc-sa/3.0/ |
| Rights holder/Author | eFloras.org Copyright © Missouri Botanical Garden |
| Source | http://www.efloras.org/florataxon.aspx?flora_id=1&taxon_id=250076855 |
Isoëtes canadensis (Engelmann) A. A. Eaton; I. saccharata Engelmann
| License | http://creativecommons.org/licenses/by-nc-sa/3.0/ |
| Rights holder/Author | eFloras.org Copyright © Missouri Botanical Garden |
| Source | http://www.efloras.org/florataxon.aspx?flora_id=1&taxon_id=250076855 |
Spores mature late summer. Margins of lakes, ponds, and streams; tidal shores and estuaries; calcareous to slightly acidic substrates in fresh, usually oligotrophic, water; Ont., Que.; Conn., Del., Fla., Maine, Md., Mass., N.H., N.J., N.Y., N.C., Pa., R.I., S.C., Vt., Va., W. Va.
| License | http://creativecommons.org/licenses/by-nc-sa/3.0/ |
| Rights holder/Author | eFloras.org Copyright © Missouri Botanical Garden |
| Source | http://www.efloras.org/florataxon.aspx?flora_id=1&taxon_id=250076855 |
Note: For many non-migratory species, occurrences are roughly equivalent to populations.
Estimated Number of Occurrences: 81 to >300
| License | http://creativecommons.org/licenses/by-nc/3.0/ |
| Rights holder/Author | NatureServe |
| Source | http://explorer.natureserve.org/servlet/NatureServe?searchName=Isoetes+riparia |