View source for Cyperus cephalanthus

{{Treatment/ID
|accepted_name=Cyperus cephalanthus
|accepted_authority=Torrey & Hooker
|publications={{Treatment/Publication
|title=Ann. Lyceum Nat. Hist. New York.
|place=3: 431. 1836
|year=1836
}}
|basionyms=
|synonyms={{Treatment/ID/Synonym
|name=Cyperus laetus var. cephalanthus
|authority=(Torrey & Hooker) Kükenthal
}}
|hierarchy=Cyperaceae;Cyperus;Cyperus subg. Cyperus;Cyperus cephalanthus
|hierarchy_nav=<div class="higher-taxa"><div class="higher-taxon"><small>family</small>[[Cyperaceae]]</div><div class="higher-taxon"><small>genus</small>[[Cyperus]]</div><div class="higher-taxon"><small>subgenus</small>[[Cyperus subg. Cyperus]]</div><div class="higher-taxon"><small>species</small>[[Cyperus cephalanthus]]</div></div>
|volume=Volume 23
|mention_page=page 180
|treatment_page=
}}<!--

--><span class="statement" id="st-undefined" data-properties=""><b>Herbs,</b> perennial, rhizomatous. <b>Culms</b> trigonous, 40–70(–100) cm × 2–3 mm, scabrid or hirtellate, either immediately proximal to apex or over distal 1/2 of culm. <b>Leaves</b> flat, 30–80 cm × 4–10 mm, scabrid on margins, ribs on abaxial surface. <b>Inflorescences</b>: spikes ovoid, 12–20 × 13–18 mm; rays 3–6, 4–10(–16) cm, glabrous; bracts 3–5, ± horizontal to reflexed, 3–12(–36) cm × 0.4–3(–5) mm, scabrid like leaves; rachilla deciduous, essentially wingless or wings inconspicuous, hyaline, 0.1(–0.2) mm wide. <b>Spikelets</b> 25–50(–80), oblong, quadrangular-compressed, 5–10 × 2.5–3.5 mm; floral scales deciduous, 4–10(–14), marginally clear, laterally brownish to clear distally, or light brown or reddish brown, blunt, laterally 3(–4)-ribbed, ovate-lanceolate, 2.5–3 × (1.2–)1.4–2 mm, often erose apically, apex acute to obtuse, entire or emarginate. <b>Flowers</b>: anthers 0.4–0.6 mm; styles 0.8–1.2 mm; stigmas 2 mm. <b>Achenes</b> brown to reddish brown, ± stipitate, ellipsoid, 1.2 × 0.5–0.6 mm, apex obtuse, scarcely to distinctly apiculate, surfaces puncticulate.</span><!--

-->{{Treatment/Body
|phenology=Fruiting summer.
|habitat=Wet prairies
|elevation=0–50 m
|distribution=La.;Okla.;Tex.;South America (Argentina;Brazil;Paraguay;Uruguay).
|discussion=<p>The combination of spreading floral scales and scabrid culms separates this rather uncommon species from any others occurring in its range. The scarcity of <i>Cyperus cephalanthus</i> in the United States and its disjunct distribution suggest it might be naturalized rather than native. It was collected early in the nineteenth century in Louisiana, and the amphitropical distribution is not without parallel in the genus (cf. 12. <i>C. eragrostis</i>).</p><!--
--><p><i>Cyperus cephalanthus</i> has been treated as a variety of the widespread, polymorphic South American C. laetus (G. Kükenthal 1935–1936). Recognition of <i>C. cephalanthus</i> as a species follows recent American floristic practice.</p>
|tables=
|references=
}}<!--

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-->{{#Taxon:
name=Cyperus cephalanthus
|author=
|authority=Torrey & Hooker
|rank=species
|parent rank=subgenus
|synonyms=Cyperus laetus var. cephalanthus
|basionyms=
|family=Cyperaceae
|phenology=Fruiting summer.
|habitat=Wet prairies
|elevation=0–50 m
|distribution=La.;Okla.;Tex.;South America (Argentina;Brazil;Paraguay;Uruguay).
|reference=None
|publication title=Ann. Lyceum Nat. Hist. New York.
|publication year=1836
|special status=
|source xml=https://jpend@bitbucket.org/aafc-mbb/fna-data-curation.git/src/f6b125a955440c0872999024f038d74684f65921/coarse_grained_fna_xml/V23/V23_306.xml
|genus=Cyperus
|subgenus=Cyperus subg. Cyperus
|species=Cyperus cephalanthus
}}<!--

-->[[Category:Treatment]][[Category:Cyperus subg. Cyperus]]