View source for Heteranthera dubia

{{Treatment/ID
|accepted_name=Heteranthera dubia
|accepted_authority=(Jacquin) MacMillan
|publications={{Treatment/Publication
|title=Metasp. Minnesota Valley,
|place=138. 1892
|year=1892
}}
|common_names=Hétéranthère litigieuse
|special_status={{Treatment/ID/Special_status
|code=W2
|label=
}}{{Treatment/ID/Special_status
|code=W1
|label=
}}{{Treatment/ID/Special_status
|code=F
|label=Illustrated
}}
|basionyms={{Treatment/ID/Basionym
|name=Commelina dubia
|authority=Jacquin
|rank=species
|publication_title=Observ. Bot.
|publication_place=3: 9. 1768
}}
|synonyms={{Treatment/ID/Synonym
|name=Heteranthera graminea
|authority=(Michaux) Vahl
|rank=species
}} {{Treatment/ID/Synonym
|name=Heteranthera liebmannii
|authority=(Buchneau) Shinners
|rank=species
}} {{Treatment/ID/Synonym
|name=Schollera graminea
|authority=(Michaux) Rafinesque
|rank=species
}} {{Treatment/ID/Synonym
|name=Zosterella dubia
|authority=(Jacquin) Small
|rank=species
}} {{Treatment/ID/Synonym
|name=Zosterella longituba
|authority=E. J. Alexander
|rank=species
}}
|hierarchy=Pontederiaceae;Heteranthera;Heteranthera dubia
|hierarchy_nav=<div class="higher-taxa"><div class="higher-taxon"><small>family</small>[[Pontederiaceae]]</div><div class="higher-taxon"><small>genus</small>[[Heteranthera]]</div><div class="higher-taxon"><small>species</small>[[Heteranthera dubia]]</div></div>
|volume=Volume 26
|mention_page=page 39, 41, 43
|treatment_page=page 42
}}<!--

--><span class="statement" id="st-d0_s0" data-properties="whole_organism duration;whole_organism growth form"><b>Plants </b>perennial.</span> <span class="statement" id="st-d0_s1" data-properties="stem reproduction;stem location;stem location;stem condition or size;stem growth form"><b>Vegetative </b>stems submersed and growing to surface, or emersed and contracted, procumbent.</span> <span class="statement" id="st-d0_s2" data-properties="flowering-stem some measurement;distal internode quantity;distal internode prominence"><b>Flowering-</b>stems less than 5 mm, no visible distal internode.</span> <span class="statement" id="st-d0_s3" data-properties="leaf architecture;leaf arrangement;leaf arrangement;blade arrangement or course or shape;blade width"><b>Sessile </b>leaves alternate or appearing opposite at nodes with inflorescences, blade linear, thin;</span> <span class="statement" id="st-d0_s4" data-properties="leaf location;leaf length;leaf width;leaf location;leaf length;leaf width">submersed leaves 3–10 cm × 1–5 mm, emersed leaves 2–4 cm × 1–3 mm.</span> <span class="statement" id="st-d0_s5" data-properties="leaf architecture;stipule architecture"><b>Petiolate </b>leaves and stipules not produced.</span> <span class="statement" id="st-d0_s6" data-properties="inflorescence architecture"><b>Inflorescences </b>1-flowered;</span> <span class="statement" id="st-d0_s7" data-properties="spathe some measurement;spathe pubescence">spathes 12–45 mm, glabrous;</span> <span class="statement" id="st-d0_s8" data-properties="peduncle presence">peduncle absent.</span> <span class="statement" id="st-d0_s9" data-properties="hour life cycle;hour quantity"><b>Flowers </b>opening within 2 hours after dawn, wilting by dusk;</span> <span class="statement" id="st-d0_s10" data-properties="perianth coloration;perianth shape;tube some measurement;limb lobe variability;limb lobe arrangement or course or shape;limb lobe some measurement">perianth yellow, salverform, tube 1.5–11 cm, limb lobes equal, of uniform color, linear, 4–11 mm;</span> <span class="statement" id="st-d0_s11" data-properties="stamen variability;stamen some measurement">stamens equal, 2–10 mm;</span> <span class="statement" id="st-d0_s12" data-properties="filament shape;filament pubescence">filaments centrally inflated, glabrous;</span> <span class="statement" id="st-d0_s13" data-properties="anther shape">anthers coiling after anthesis, by early afternoon;</span> <span class="statement" id="st-d0_s14" data-properties="style pubescence;style pubescence">style glabrous or scarcely pubescent.</span> <span class="statement" id="st-d0_s15" data-properties="seed architecture;seed length;seed width;2n chromosome quantity"><b>Seeds </b>7–30, 12–22-winged, 1–1.6 × 0.5–1.3 mm. <b>2n</b> = 30.</span><!--

-->{{Treatment/Body
|phenology=Flowering Apr–Nov.
|habitat=Streams, rivers, ponds, lakes
|elevation=0–1500 m
|distribution=B.C.;Man.;N.B.;Ont.;Que.;Ala.;Ariz.;Ark.;Calif.;Conn.;Del.;D.C.;Fla.;Ill.;Ind.;Iowa;Kans.;Ky.;La.;Md.;Mass.;Mich.;Minn.;Mo.;Nebr.;N.H.;N.J.;N.Y.;N.C.;N.Dak.;Ohio;Okla.;Oreg.;Pa.;S.Dak.;Tenn.;Tex.;Vt.;Va.;Wash.;W.Va.;Wis.;Mexico;West Indies (Cuba)
|discussion=<p>Extensive vegetative variation has been noted in the leaf morphology of Heteranthera dubia (C. N. Horn 1983). Plants in ponds and lakes tend to have longer, narrower leaves than plants from streams and rivers with a unidirectional current. Laboratory growth experiments revealed at least some genetic component to the differences (C. N. Horn 1981).</p><!--
--><p>Plants are most extensive in their growth in alkaline waters (J. B. Moyle 1945), and, if plants are in a great enough density, they can cause an increase in water pH (E. B. Hollingsworth 1966). Growth in some lakes, streams, and canals has resulted in the species being considered a weed (E. B. Hollingsworth 1966).</p><!--
--><p>Some authors (J. K. Small and J. J. Carter 1913; E. J. Alexander 1937) have transferred this species to the segregate genus Zosterella, based on the equal stamens (vs. nonequal in Heteranthera s.s.) and narrow, erect anthers (vs. broad and versatile). Small and Carter first described Zosterella citing only the above differences. Alexander later reported several more distinguishing characteristics: anthers coiling after anthesis, spathes sessile, and seeds relatively few. Recent molecular work by S. W. Graham et al. (1998) using chloroplast DNA suggests that Heteranthera dubia is clearly nested within the genus Heteranthera and is most closely related to H. seubertiana Solms, a tropical species.</p><!--
--><p>Variation in perianth size has been a basis for separate recognition of Heteranthera liebmannii, or its equivalent, Zosterella longituba (E. J. Alexander 1937; D. S. Correll and H. B. Correll 1972). Alexander used differences in the lengths of perianth tube and lobes, and length of the perianth tube relative to that of the spathe to distinguish that segregate species. Study has revealed three causes of variation in perianth tube length: plants from populations farther north have a shorter perianth tube (herbarium study); flowers that develop under water have minimal perianth tube elongation, and the perianth remains completely within the spathe (J. W. Thieret 1972b; R. B. Wylie 1917); and lower overnight air temperatures result in less perianth tube elongation (controlled experiments). The specific epithet liebmannii was first applied to this entity by F. Buchneau (1872), under Potamogeton, and the type material consists of a series of specimens from Pital, Mexico, having only cleistogamous flowers. Later, the true generic identity of the specimens was realized. E. J. Alexander (1937), convinced that they represent a species distinct from those in Texas and Mexico, proposed the name Zosterella longituba for that entity, and placed Potamogeton liebmannii in synonomy. Since Alexander should have used the epithet liebmannii, which was not blocked in Zosterella, the name Z. longituba is illegitimate. An additional complication is that the types of P. liebmannii are morphologically ambiguous, since they include only cleistogamous flowers. Hence it is impossible, with current knowledge, to determine conclusively which of the two forms of Heteranthera dubia (as I recognize them) is represented by those types.</p><!--
--><p>Populations are known to be infected by the fungal parasite Membranosorus heterantherae Ostenfeld & Peterson (H. S. Forest et al. 1986). The subsequent growths may be of two forms depending on whether they develop above the substrate on stems (nodal galls) or underground on roots (root galls).</p>
|tables=
|references=
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-->{{#Taxon:
name=Heteranthera dubia
|authority=(Jacquin) MacMillan
|rank=species
|parent rank=genus
|synonyms=Heteranthera graminea;Heteranthera liebmannii;Schollera graminea;Zosterella dubia;Zosterella longituba
|basionyms=Commelina dubia
|family=Pontederiaceae
|phenology=Flowering Apr–Nov.
|habitat=Streams, rivers, ponds, lakes
|elevation=0–1500 m
|distribution=B.C.;Man.;N.B.;Ont.;Que.;Ala.;Ariz.;Ark.;Calif.;Conn.;Del.;D.C.;Fla.;Ill.;Ind.;Iowa;Kans.;Ky.;La.;Md.;Mass.;Mich.;Minn.;Mo.;Nebr.;N.H.;N.J.;N.Y.;N.C.;N.Dak.;Ohio;Okla.;Oreg.;Pa.;S.Dak.;Tenn.;Tex.;Vt.;Va.;Wash.;W.Va.;Wis.;Mexico;West Indies (Cuba)
|reference=None
|publication title=Metasp. Minnesota Valley,
|publication year=1892
|special status=W2;W1;Illustrated
|source xml=https://bibilujan@bitbucket.org/aafc-mbb/fna-fine-grained-xml.git/src/84153f6d59a0a91d69695978a64cee7560374f8e/V26/V26_8.xml
|genus=Heteranthera
|species=Heteranthera dubia
|2n chromosome quantity=30
|anther shape=coiling
|blade arrangement or course or shape=linear
|blade width=thin
|distal internode prominence=visible
|distal internode quantity=no
|filament pubescence=glabrous
|filament shape=inflated
|flowering-stem some measurement=0mm;5mm
|hour life cycle=wilting
|hour quantity=2
|inflorescence architecture=1-flowered
|leaf architecture=petiolate;sessile
|leaf arrangement=opposite;alternate
|leaf length=2cm;4cm
|leaf location=emersed;submersed
|leaf width=1mm;3mm
|limb lobe arrangement or course or shape=linear
|limb lobe some measurement=4mm;11mm
|limb lobe variability=equal
|peduncle presence=absent
|perianth coloration=yellow
|perianth shape=salverform
|seed architecture=7-30,12-22-winged
|seed length=1mm;1.6mm
|seed width=0.5mm;1.3mm
|spathe pubescence=glabrous
|spathe some measurement=12mm;45mm
|stamen some measurement=2mm;10mm
|stamen variability=equal
|stem condition or size=contracted
|stem growth form=procumbent
|stem location=emersed;submersed
|stem reproduction=vegetative
|stipule architecture=petiolate
|style pubescence=pubescent;glabrous
|tube some measurement=1.5cm;11cm
|whole_organism duration=perennial
|whole_organism growth form=plant
}}<!--

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