View source for Ceratophyllum echinatum

{{Treatment/ID
|accepted_name=Ceratophyllum echinatum
|accepted_authority=A. Gray
|publications={{Treatment/Publication
|title=Ann. Lyceum Nat. Hist. New York
|place=4: 49. 1837
|year=1837
}}
|common_names=Hornwort;cornifle échinée
|special_status={{Treatment/ID/Special_status
|code=E
|label=Endemic
}}{{Treatment/ID/Special_status
|code=F
|label=Selected by author to be illustrated
}}{{Treatment/ID/Special_status
|code=W
|label=Weedy
}}
|basionyms=
|synonyms={{Treatment/ID/Synonym
|name=Ceratophyllum demersum var. echinatum
|authority=(A. Gray) A. Gray
}}{{Treatment/ID/Synonym
|name=Ceratophyllum submersum var. echinatum
|authority=(A. Gray) Wilmot-Dear
}}
|hierarchy=Ceratophyllaceae;Ceratophyllum;Ceratophyllum echinatum
|hierarchy_nav=<div class="higher-taxa"><div class="higher-taxon"><small>family</small>[[Ceratophyllaceae]]</div><div class="higher-taxon"><small>genus</small>[[Ceratophyllum]]</div><div class="higher-taxon"><small>species</small>[[Ceratophyllum echinatum]]</div></div>
|volume=Volume 3
|mention_page=
|treatment_page=
}}<!--

--><span class="statement" id="st-undefined" data-properties=""><b>Stems </b>to 1 m; apical leaf whorls not densely crowded. <b>Leaves</b> dark green or olive-green, fine-textured. <b>Leaf</b> blade simple or forked into 2-10 ultimate segments (forking of largest leaves 3d or 4th order), proximal segments often conspicuously inflated, mature leaf whorls 25-55 mm diam., marginal denticles weak and inconspicuous, weakly exserted, not raised on broad base of green tissue; 1st leaves of plumule forked. <b>Achene</b> dark green or brown, body (excluding spines) 4.5-6 × 2.5-4.5 × 1.5-3 mm, basal spines 2 (rarely absent), straight or curved, 1-5 mm, marginal spines 2-13, 0.5-6.5 mm, terminal spine straight, 1.5-7.5 mm, margins winged. <b>2n</b> = 24.</span><!--

-->{{Treatment/Body
|phenology=Flowering spring–summer.
|habitat=Fresh water of lakes, ponds, marshes, swamps
|elevation=0-500 m
|distribution=B.C.;Man.;N.B.;N.S.;Ont.;Que.;Ala.;Ark.;Conn.;Del.;D.C.;Fla.;Ga.;Ill.;Ind.;Iowa;Kans.;Ky.;La.;Maine;Md.;Mass.;Mich.;Minn.;Miss.;Mo.;N.H.;N.J.;N.Y.;N.C.;Ohio;Okla.;Oreg.;Pa.;R.I.;S.C.;Tenn.;Tex.;Vt.;Va.;Wash.;W.Va.;Wis.
|discussion=<p>Principally an eastern North American species–and the only species of its genus endemic to North America–Ceratophyllum echinatum is disjunct in the Pacific Northwest as a result of repeated Pleistocene glaciation. The habitats of C. echinatum are typically more acidic (avg. pH 6.6) than those of C. demersum (avg. pH 7.4). The two species only rarely coexist. Ceratophyllum echinatum also thrives in cooler, clearer, and more oligotrophic water than C. demersum and often is found in more ephemeral sites, such as shrub swamps (e.g., with Cephalanthus occidentalis) and beaver ponds.</p><!--
--><p>This species, relatively uncommon, is fast disappearing from much of its range because of habitat alteration or destruction and the introduction of nonindigenous species; steps should be taken to secure its conservation. Unlike Ceratophyllum demersum, C. echinatum does not attain status as a serious weed.</p>
|tables=
|references=
}}<!--

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-->{{#Taxon:
name=Ceratophyllum echinatum
|author=
|authority=A. Gray
|rank=species
|parent rank=genus
|synonyms=Ceratophyllum demersum var. echinatum;Ceratophyllum submersum var. echinatum
|basionyms=
|family=Ceratophyllaceae
|phenology=Flowering spring–summer.
|habitat=Fresh water of lakes, ponds, marshes, swamps
|elevation=0-500 m
|distribution=B.C.;Man.;N.B.;N.S.;Ont.;Que.;Ala.;Ark.;Conn.;Del.;D.C.;Fla.;Ga.;Ill.;Ind.;Iowa;Kans.;Ky.;La.;Maine;Md.;Mass.;Mich.;Minn.;Miss.;Mo.;N.H.;N.J.;N.Y.;N.C.;Ohio;Okla.;Oreg.;Pa.;R.I.;S.C.;Tenn.;Tex.;Vt.;Va.;Wash.;W.Va.;Wis.
|reference=None
|publication title=Ann. Lyceum Nat. Hist. New York
|publication year=1837
|special status=Endemic;Selected by author to be illustrated;Weedy
|source xml=https://jpend@bitbucket.org/aafc-mbb/fna-data-curation.git/src/9216fc802291cd3df363fd52122300479582ede7/coarse_grained_fna_xml/V3/V3_454.xml
|genus=Ceratophyllum
|species=Ceratophyllum echinatum
}}<!--

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