View source for Eleocharis fallax

{{Treatment/ID
|accepted_name=Eleocharis fallax
|accepted_authority=Weatherby
|publications={{Treatment/Publication
|title=Rhodora
|place=24: 23. 1922
|year=1922
}}
|special_status={{Treatment/ID/Special_status
|code=F
|label=Illustrated
}}{{Treatment/ID/Special_status
|code=E
|label=Endemic
}}{{Treatment/ID/Special_status
|code=C
|label=Conservation concern
}}
|basionyms=
|synonyms=
|hierarchy=Cyperaceae;Eleocharis;Eleocharis subg. Eleocharis;Eleocharis sect. Eleocharis;Eleocharis (sect. Eleocharis) ser. Eleocharis;Eleocharis fallax
|hierarchy_nav=<div class="higher-taxa"><div class="higher-taxon"><small>family</small>[[Cyperaceae]]</div><div class="higher-taxon"><small>genus</small>[[Eleocharis]]</div><div class="higher-taxon"><small>subgenus</small>[[Eleocharis subg. Eleocharis]]</div><div class="higher-taxon"><small>section</small>[[Eleocharis sect. Eleocharis]]</div><div class="higher-taxon"><small>series</small>[[Eleocharis (sect. Eleocharis) ser. Eleocharis]]</div><div class="higher-taxon"><small>species</small>[[Eleocharis fallax]]</div></div>
|volume=Volume 23
|mention_page=page 66, 68, 77, 79
|treatment_page=page 78
}}<!--

--><span class="statement" id="st-undefined" data-properties=""><b>Plants </b>perennial, mat-forming; rhizomes evident, long, 1–2 mm thick, firm, cortex persistent, longer internodes 5–10(–20) mm, scales sometimes fugaceous, 5–7 mm, papery (to membranous), sometimes fibrous. <b>Culms</b> terete, often with to 12 blunt ridges when dry, 30–75 cm × 0.5–1.5 mm, firm, internally spongy. <b>Leaves</b>: distal leaf sheaths persistent, not splitting, proximally dark red, distally stramineous or green, papery to membranous, apex dark redbrown, obtuse, not callose, tooth rarely present on some culms, 0.2 mm. <b>Spikelets</b> ovoid or subspheric, 5–12 × 2–3(–4) mm, apex acute to obtuse; proximal scale amplexicaulous, entire; subproximal scale with flower; floral scales deciduous, often spreading in fruit, 10–35, 3 per mm of rachilla, red-brown to blackish brown, midrib regions sometimes green, ovate, 2.5–3 × 1.7 mm, apex entire, obtuse to acute, often carinate in distal part of spikelet. <b>Flowers</b>: perianth bristles 1–5, brown, stout, very unequal, rudimentary to equaling achene; stamens unknown [absent from specimens]; styles 3-fid or some 2-fid. <b>Achenes</b> not persistent, dark yellow or medium brown, obovoid to obpyriform, compressed trigonous, or some thickly biconvex, angles evident, 1.1–1.5 × 0.95–1.25 mm, apex rounded, neck very short (to absent), finely rugulose at 10–20X, 20 or more horizontal ridges in vertical series, finely cancellate at 20–30X. <b>Tubercles</b> whitish to brown, pyramidal, not depressed, as high as wide, 0.3–0.5 × 0.4–0.6 mm. <b>2n</b> = 42.</span><!--

-->{{Treatment/Body
|phenology=Fruiting late summer.
|habitat=Coastal, fresh to brackish pond and lakeshores, marsh
|elevation=0–10 m
|distribution=N.S.;Mass.;N.J.
|discussion=<p>Of conservation concern.</p><!--
--><p>The taxonomic status of <i>Eleocharis fallax</i> is problematic. I have seen only the type, from 1919 from a pond on Cape Cod, Massachusetts; a specimen from 1955 from Inverness County, Nova Scotia; and a specimen from the Passaic River marshes in New Jersey. It is reportedly extirpated from the type locality (M. L. Fernald 1950). Another specimen from Cape Cod is typical of <i>E. fallax</i> except for some lenticular achenes. I have not seen a voucher for the material, reportedly collected by H. K. Svenson from a brackish marsh on Plum Island, Essex County, Massachusetts, from which S.-O. Strandhede (1967) counted the chromosome number. It seems possible that these collections are of hybrid origin from <i>E. elliptica</i> and either <i>E. erythropoda</i> or <i>E. uniglumis</i> var. halophila (M. L. Fernald 1950). The plants are similar to <i>E. erythropoda</i> except for their trigonous, rougher achenes and sometimes fibrous rhizome scales, which suggests introgression from <i>E. elliptica</i>. Because some specimens of <i>E. ambigens</i>, including the type, have mixtures of lenticular and trigonous achenes, <i>E. fallax</i> is often treated as conspecific with <i>E. ambigens</i>, from which it differs only in its 3-fid styles, trigonous, more rugulose achenes, and higher tubercles. It seems best to recognize <i>E. fallax</i> as a species pending further research because the plants bear many, apparently normal achenes and are not exactly intermediate between their putative parents, and to avoid using a name for the widespread <i>E. ambigens</i> that may apply only to rare hybrids.</p>
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|references=
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-->{{#Taxon:
name=Eleocharis fallax
|authority=Weatherby
|rank=species
|parent rank=series
|synonyms=
|basionyms=
|family=Cyperaceae
|phenology=Fruiting late summer.
|habitat=Coastal, fresh to brackish pond and lakeshores, marsh
|elevation=0–10 m
|distribution=N.S.;Mass.;N.J.
|reference=None
|publication title=Rhodora
|publication year=1922
|special status=Illustrated;Endemic;Conservation concern
|source xml=https://bitbucket.org/aafc-mbb/fna-data-curation/src/2e0870ddd59836b60bcf96646a41e87ea5a5943a/coarse_grained_fna_xml/V23/V23_104.xml
|genus=Eleocharis
|subgenus=Eleocharis subg. Eleocharis
|section=Eleocharis sect. Eleocharis
|series=Eleocharis (sect. Eleocharis) ser. Eleocharis
|species=Eleocharis fallax
}}<!--

-->[[Category:Treatment]][[Category:Eleocharis (sect. Eleocharis) ser. Eleocharis]]