''Isoetes maritima'', the maritime quillwort, is a quillwort in the

Isoetaceae Isoetaceae is a family including living quillworts ('' Isoetes'') and comparable extinct herbaceous lycopsids ('' Tomiostrobus''). References External links * * Lycophytes Plant families {{Lycophyte-stub ...

family. It is native to

Alaska Alaska ( ) is a non-contiguous U.S. state on the northwest extremity of North America. Part of the Western United States region, it is one of the two non-contiguous U.S. states, alongside Hawaii. Alaska is also considered to be the north ...

British Columbia British Columbia is the westernmost Provinces and territories of Canada, province of Canada. Situated in the Pacific Northwest between the Pacific Ocean and the Rocky Mountains, the province has a diverse geography, with rugged landscapes that ...

, and

Washington state Washington, officially the State of Washington, is a state in the Pacific Northwest region of the United States. It is often referred to as Washington State to distinguish it from the national capital, both named after George Washington ...

.L. Underwood, Botanical Gazette 13: 94. 1888. It bears eight to fifteen dark green, erect, rigid leaves that are each two to five centimeters long and 1.5 millimeters wide. The oval sporangia are small and inconspicuous, measuring at four millimeters long. The velum covers a third to a half of the sporangia. The white microspores are kidney-shaped and 30-36 micrometers long. The white megaspores are spherical and 490-670 micrometers in diameter. It is similar to '' I. echinospora'', but with blunt spines and crests on the megaspores. ''I. echinospora'' has sharp, thin spines, though most of the other species in the genus have no megasporal spines.Flora of North America vol 2.
/ref> The epithet "''maritima''" and the common name "maritime quillwort", meaning "of the sea or ocean", are misnomers. Because it was first discovered by Macoun near tidal flats in British Columbia, it was treated as a coastal species. Since that time, however, it has been found in fresh-water lakes and streams.

References

maritima Flora of Alberta Flora of Alaska Flora of British Columbia Flora of Washington (state) Plants described in 1888 Flora of Yukon Flora without expected TNC conservation status Taxa named by Lucien Marcus Underwood {{Lycophyte-stub