View source for Tetragonotheca

{{Treatment/ID
|accepted_name=Tetragonotheca
|accepted_authority=Linnaeus
|publications={{Treatment/Publication
|title=Sp. Pl.
|place=2: 903. 1753
|year=1753
}}{{Treatment/Publication
|title=Gen. Pl. ed.
|place=5, 384. 1754
|year=1754
}}
|basionyms=
|synonyms=
|hierarchy=Asteraceae;Asteraceae tribe Heliantheae;Asteraceae (tribe Heliantheae) subtribe Galinsoginae;Tetragonotheca
|hierarchy_nav=<div class="higher-taxa"><div class="higher-taxon"><small>family</small>[[Asteraceae]]</div><div class="higher-taxon"><small>tribe</small>[[Asteraceae tribe Heliantheae]]</div><div class="higher-taxon"><small>subtribe</small>[[Asteraceae (tribe Heliantheae) subtribe Galinsoginae]]</div><div class="higher-taxon"><small>genus</small>[[Tetragonotheca]]</div></div>
|etymology=Greek tetra, four, gonio, angle, and theca, container, alluding to quadrangular involucres
|volume=Volume 21
|mention_page=page 176
|treatment_page=page 178
}}<!--

--><span class="statement" id="st-undefined" data-properties=""><b>Perennials,</b> mostly 30–120 cm. <b>Stems</b> erect. <b>Leaves</b> basal and/or cauline; mostly opposite; petiolate, subpetiolate, or sessile (bases sometimes connate-perfoliate); blades lanceolate, ovate, rhombic, or rounded-deltate, sometimes pinnatifid, ultimate margins usually toothed, faces glabrate, sparsely hispidulous, or puberulent, gland-dotted. <b>Heads</b> radiate, borne singly or in loose, corymbiform arrays. <b>Involucres</b> obpyramidal to hemispheric, 12–25+ mm diam. <b>Phyllaries</b> persistent, 10–25+ in ± 2 series (outer 4 broadly lanceolate, foliaceous, the inner ovate to lanceolate, smaller, more scarious, each subtending a ray floret). <b>Receptacles</b> conic, paleate (paleae persistent, lanceolate to lance-ovate, flat or weakly conduplicate, apices acute). <b>Ray</b> florets 6–21+, pistillate, fertile; corollas yellow (often with reddish nerves). <b>Disc</b> florets 25–150+, bisexual, fertile; corollas yellow, tubes (basally dilated) much shorter than ampliate, cylindric throats, lobes 5, deltate. <b>Cypselae</b> ± ovoid or plumply 4- or 5-angled, finely 32–40-ribbed, sparsely strigose or glabrous; pappi 0, or of 1–10+ subulate to acerose scales (to 0.5 mm), or of 16–30, ± spatulate scales (0.5–2 mm). <b>x</b> = 17.</span><!--

-->{{Treatment/Body
|distribution=s United States;n Mexico.
|discussion=<p>Species 4 (4 in the flora).</p>
|tables=
|references={{Treatment/Reference
|id=turner1980a
|text=Turner, B. L. and D. Dawson. 1980. Taxonomy of Tetragonotheca (Asteraceae–Heliantheae). Sida 8: 296–303.
}}
}}<!--

--><div class="treatment-key">
==Key==
<div class="treatment-key-group">
  
{| class="wikitable fna-keytable"
|-id=key-0-1
|1
|Pappi of 16–30, ± obovate to spatulate scales 0.5–2 mm
|[[#key-0-2| > 2]]
|-id=key-0-1
|1
|Pappi 0, or of 1–10+ subulate to acerose scales to 0.5 mm
|[[#key-0-3| > 3]]
|-id=key-0-2
|2
|Leaves mostly cauline (distal connate-perfoliate); ray florets 12–13, laminae 8–18 mm
|[[Tetragonotheca ludoviciana|Tetragonotheca ludoviciana]]
|-id=key-0-2
|2
|Leaves mostly basal (cauline much smaller, none connate-perfoliate); ray florets 16–21+, laminae 20–30+ mm
|[[Tetragonotheca repanda|Tetragonotheca repanda]]
|-id=key-0-3
|3
|Stems sparsely tomentulose or glabrous (nodes usually auriculate-appendaged); ray laminae 10–18 mm; cypselae ± quadrate, 2.5–4 mm
|[[Tetragonotheca texana|Tetragonotheca texana]]
|-id=key-0-3
|3
|Stems patently to retrorsely ± villous; ray laminae 20–40+ mm; cypselae ± ovoid, 4–6 mm
|[[Tetragonotheca helianthoides|Tetragonotheca helianthoides]]
|}
</div></div><!--

-->{{#Taxon:
name=Tetragonotheca
|author=John L. Strother
|authority=Linnaeus
|rank=genus
|parent rank=subtribe
|synonyms=
|basionyms=
|family=Asteraceae
|distribution=s United States;n Mexico.
|reference=turner1980a
|publication title=Sp. Pl.;Gen. Pl. ed.
|publication year=1753;1754
|special status=
|source xml=https://jpend@bitbucket.org/aafc-mbb/fna-data-curation.git/src/8f726806613d60c220dc4493de13607dd3150896/coarse_grained_fna_xml/V19-20-21/V21_435.xml
|tribe=Asteraceae tribe Heliantheae
|subtribe=Asteraceae (tribe Heliantheae) subtribe Galinsoginae
|genus=Tetragonotheca
}}<!--

-->[[Category:Treatment]][[Category:Asteraceae (tribe Heliantheae) subtribe Galinsoginae]]