''Isoetes maritima'', the maritime quillwort, is a
quillwort
''Isoetes'', commonly known as the quillworts, is the only extant genus of plants in the family Isoetaceae, which is in the class of lycopods. There are currently 192 recognized species, with a cosmopolitan distribution but with the individual s ...
in the
Isoetaceae
Isoetaceae is a family including living quillworts (''Isoetes'') and comparable extinct herbaceous lycopsids (''Tomiostrobus
''Tomiostrobus'' is an extinct quillwort genus from the Early Triassic of Australia, China and Russia, which was espe ...
family. It is native to
Alaska
Alaska ( ; russian: Аляска, Alyaska; ale, Alax̂sxax̂; ; ems, Alas'kaaq; Yup'ik: ''Alaskaq''; tli, Anáaski) is a state located in the Western United States on the northwest extremity of North America. A semi-exclave of the U.S. ...
,
British Columbia
British Columbia (commonly abbreviated as BC) is the westernmost province of Canada, situated between the Pacific Ocean and the Rocky Mountains. It has a diverse geography, with rugged landscapes that include rocky coastlines, sandy beaches, ...
, and
Washington state
Washington (), officially the State of Washington, is a state in the Pacific Northwest region of the Western United States. Named for George Washington—the first U.S. president—the state was formed from the western part of the 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
megaspore
Megaspores, also called macrospores, are a type of spore that is present in heterosporous plants. These plants have two spore types, megaspores and microspores. Generally speaking, the megaspore, or large spore, germinates into a female gamet ...
s. ''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.](_blank)
/ref> The epithet "''maritima''" and the common name "maritime quillwort
''Isoetes'', commonly known as the quillworts, is the only extant genus of plants in the family Isoetaceae, which is in the class of lycopods. There are currently 192 recognized species, with a cosmopolitan distribution but with the individual s ...
", 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