View source for Stuckenia filiformis

{{Treatment/ID
|accepted_name=Stuckenia filiformis
|accepted_authority=(Persoon) Börner
|publications={{Treatment/Publication
|title=Flora fur das deutsche Volk
|place=713. 1912
|year=1912
}}
|common_names=Threadleaf-pondweed
|basionyms={{Treatment/ID/Basionym
|name=Potamogeton filiformis
|authority=Persoon
|rank=species
|publication_title=Syn. Pl.
|publication_place=1: 152. 1805
}}
|synonyms=
|hierarchy=Potamogetonaceae;Stuckenia;Stuckenia filiformis
|hierarchy_nav=<div class="higher-taxa"><div class="higher-taxon"><small>family</small>[[Potamogetonaceae]]</div><div class="higher-taxon"><small>genus</small>[[Stuckenia]]</div><div class="higher-taxon"><small>species</small>[[Stuckenia filiformis]]</div></div>
|volume=Volume 22
|mention_page=
|treatment_page=
}}<!--

--><span class="statement" id="st-undefined" data-properties=""><b>Stems </b>freely branching proximally, sparsely branching distally, subterete, (10–)20–60(–100) cm. <b>Leaves</b>: length and width of those on main stem only slightly larger than those on branches; stipules with stipular sheaths often inflated on proximal portion of stem, 1–4(–9.5) cm, summit of midstem stipules tight to stem, ca. ± same width as stem, ligule 2–20 mm, distinct, especially on distal stipules; blade filiform or slenderly linear, 1–15 cm × 0.2–2(–3.7) mm, apex notched, blunt, or short-apiculate; veins 1–3. <b>Inflorescences</b>: peduncles terminal, erect, filiform to slender, 2–10(–15) cm; spikes cylindric to moniliform, 5–55 mm; verticels 2–6(–9). <b>Fruits</b> dark brown, obovoid, 2–3 × 1.5–2.4 mm; beak inconspicuous.</span><!--

-->{{Treatment/Body
|distribution=Alta.;B.C.;Man.;N.B.;N.S.;N.W.T.;Nunavut;Ont.;P.E.I.;Que.;Sask.;Yukon;Alaska;Ariz.;Calif.;Colo.;Idaho;Iowa;Maine;Mich.;Minn.;Mont.;N.Dak.;N.H.;N.J.;N.Mex.;N.Y.;Nebr.;Nev.;Ohio;Oreg.;Pa.;S.Dak.;Utah;Vt.;Wash.;Wis.;Wyo.;nearly worldwide.
|discussion=<p>Three distinct subspecies seemingly apparently occur in North America. They are separated mainly by the size of the plants and the peduncle characteristics. <i>Stuckenia filiformis </i>subsp.<i> occidentalis</i> typically grows in cold deep water, standing or with a strong current. This variety tends to become robust and is easily confused with <i>Stuckenia vaginata</i> and <i>S. striata</i>. <i>Stuckenia filiformis </i>subsp.<i> alpina</i> is a much smaller plant typically growing in standing waters. <i>Stuckenia filiformis </i>subsp.<i> filiformis</i> is restricted to the far north. In the intermountain region of western United States is a more robust form that is quite similar to <i>S. filiformis </i>subsp.<i> alpina</i> but although it has previously been recognized as <i>Potamogeton</i> [<i>Stuckenia</i>] filiformis <i></i>var.<i> macounii</i> Morong (J. L. Reveal 1977b).</p><!--
--><p>Subspecies ca. 5 (3 in the flora).</p>
|tables=
|references=
}}<!--

--><div class="treatment-key">
==Key==
<div class="treatment-key-group">
  
{| class="wikitable fna-keytable"
|-id=key-0-1
|1
|Plants 20–100 cm; stipules on proximal portion of stem inflated, disintegrating with age; fruits often absent.
|[[Stuckenia filiformis subsp. occidentalis|Stuckenia filiformis subsp. occidentalis]]
|-id=key-0-1
|1
|Plants 10–30 cm; stipules on proximal portion of stem tightly clasping or slightly enlarged, persistent; fruits common.
|[[#key-0-2| > 2]]
|-id=key-0-2
|2
|Peduncles Peduncles with flowers and/or fruits 4 cm or more apart; leaves 0.2–0.5 mm wide.
|[[Stuckenia filiformis subsp. Filiformis|Stuckenia filiformis subsp. Filiformis]]
|-id=key-0-2
|2
|Peduncles with flowers and/or fruits less than 4 cm apart; leaves to 1 mm widee.
|[[Stuckenia filiformis subsp. alpina|Stuckenia filiformis subsp. alpina]]
|}
</div></div><!--

-->{{#Taxon:
name=Stuckenia filiformis
|authority=(Persoon) Börner
|rank=species
|parent rank=genus
|synonyms=
|basionyms=Potamogeton filiformis
|family=Potamogetonaceae
|distribution=Alta.;B.C.;Man.;N.B.;N.S.;N.W.T.;Nunavut;Ont.;P.E.I.;Que.;Sask.;Yukon;Alaska;Ariz.;Calif.;Colo.;Idaho;Iowa;Maine;Mich.;Minn.;Mont.;N.Dak.;N.H.;N.J.;N.Mex.;N.Y.;Nebr.;Nev.;Ohio;Oreg.;Pa.;S.Dak.;Utah;Vt.;Wash.;Wis.;Wyo.;nearly worldwide.
|reference=None
|publication title=Flora fur das deutsche Volk
|publication year=1912
|special status=
|source xml=https://bitbucket.org/aafc-mbb/fna-data-curation/src/2e0870ddd59836b60bcf96646a41e87ea5a5943a/coarse_grained_fna_xml/V22/V22_233.xml
|genus=Stuckenia
|species=Stuckenia filiformis
}}<!--

-->

[[Category:Treatment]]
[[Category:Stuckenia]]
[[Category:Revised Since Print]]