View source for Elodea

{{Treatment/ID
|accepted_name=Elodea
|accepted_authority=Michaux
|publications={{Treatment/Publication
|title=Flora Boreali-Americana
|place=1: 20. 1803
|year=1803
}}
|common_names=Water-weed
|basionyms=
|synonyms=
|hierarchy=Hydrocharitaceae;Elodea
|hierarchy_nav=<div class="higher-taxa"><div class="higher-taxon"><small>family</small>[[Hydrocharitaceae]]</div><div class="higher-taxon"><small>genus</small>[[Elodea]]</div></div>
|etymology=Greek helodes, marshy
|volume=Volume 22
|mention_page=
|treatment_page=
}}<!--

--><span class="statement" id="st-undefined" data-properties=""><b>Plants </b>perennial, of fresh waters. <b>Rhizomes</b> and stolons absent. <b>Erect</b> stems rooted in substrate, branched or unbranched, elongate. <b>Leaves</b> cauline, whorled, 3–7 at each node, or leaves opposite at 4+ proximalmost nodes, submersed, sessile; blade linear to linear-lanceolate, apex acute; midvein without lacunae along side(s), blade uniform in color throughout;; abaxial surfacely without prickles or aerenchyma; intravaginal squamules entire. <b>Inflorescences</b> solitary, sessile; spathes not winged. <b>Flowers</b> unisexual, staminate and pistillate on different plants, or rarely bisexual, usually projected to surface of water by elongate floral tube base, sessile; petals white. <b>Staminate</b> flowers: filaments distinct or 3 inner connate ½ their length; anthers oval; pollen in monads or tetrads. <b>Pistillate</b> flowers: ovary 1-locular; styles 3, not 2-fid. <b>Fruits</b> ovoid to lance-ellipsoid, smooth, dehiscing irregularly. <b>Seeds</b> cylindric to fusiform, glabrous to hirsute.</span><!--

-->{{Treatment/Body
|distribution=North America;Central America;South America;Europe.
|discussion=<p>An additional name, <i>Elodea</i> schweinitzii (G. Planchon) Caspary, has appeared in North American literature. Although it was accepted by some (H. St. John 1965), others stated, "<i>Elodea</i> schweinitzii is something of a taxonomist's nightmare" (C. D. K. Cook and K. Urmi-K&ouml;nig 1985). The few collections referable to the name are exceedingly variable, so variable in fact that the authors added, "the main character is variability itself." I am following Cook and Urmi-K&ouml;nig in not accepting the taxon.</p><!--
--><p>Species 5 (3 in the flora).</p>
|tables=
|references={{Treatment/Reference
|id=cook1985b
|text=Cook, C. D. K. and K. Urmi-König. 1985. A revision of the genus Elodea (Hydrocharitaceae). Aquatic Bot. 21: 111--156. St.
}}{{Treatment/Reference
|id=john1920a
|text=John, H. 1920. The genus Elodea in New England. Rhodora 22: 17--29. St.
}}{{Treatment/Reference
|id=john1962a
|text=John, H. 1962. Monograph of the genus Elodea (Hydrocharitaceae): Part I. The species found in the Great Plains, the Rocky Mountains, and the Pacific states and provinces of North America. Res. Stud. State Coll. Wash. 30(2): 19--44. St.
}}{{Treatment/Reference
|id=john1965a
|text=John, H. 1965. Monograph of the genus Elodea: Part 4 and summary: The species of eastern and central North America. Rhodora 67: 1--—35, 155--180.
}}{{Treatment/Reference
|id=shinners1956a
|text=Shinners, L. H. 1956. Elodea correct without being conserved. Rhodora 58: 162.
}}
}}<!--

--><div class="treatment-key">
==Key==
<div class="treatment-key-group">
  
{| class="wikitable fna-keytable"
|-id=key-0-1
|1
|Staminate spathes 4 mm or less; styles usually 2 mm or less; leaves usually less than 1.7 mm wide.
|[[Elodea nuttallii|Elodea nuttallii]]
|-id=key-0-1
|1
|Staminate spathes 6 mm or more; styles usually more than 2 mm; leaves usually more than 1.8 mm wide.
|[[#key-0-2| > 2]]
|-id=key-0-2
|2
|Pollen in tetrads; staminate pedicels detaching before or during anthesis; anthers 3 mm or less; leaves mostly in 3s; seeds 4.5–5.7 mm or more.
|[[Elodea canadensis|Elodea canadensis]]
|-id=key-0-2
|2
|Pollen in monads; staminate pedicels remaining briefly following anthesis; anthers 3–4.5 mm; some leaves in 2s; seeds 4 mm or less.
|[[Elodea bifoliata|Elodea bifoliata]]
|}
</div></div><!--

-->{{#Taxon:
name=Elodea
|author=
|authority=Michaux
|rank=genus
|parent rank=family
|synonyms=
|basionyms=
|family=Hydrocharitaceae
|distribution=North America;Central America;South America;Europe.
|reference=cook1985b;john1920a;john1962a;john1965a;shinners1956a
|publication title=Flora Boreali-Americana
|publication year=1803
|special status=
|source xml=https://jpend@bitbucket.org/aafc-mbb/fna-data-curation.git/src/f6b125a955440c0872999024f038d74684f65921/coarse_grained_fna_xml/V22/V22_602.xml
|genus=Elodea
}}<!--

-->[[Category:Treatment]][[Category:Hydrocharitaceae]]