View source for Acanthospermum

{{Treatment/ID
|accepted_name=Acanthospermum
|accepted_authority=Schrank
|publications={{Treatment/Publication
|title=Pl. Rar. Hort. Monac.
|place=2: plate 53. 1820
|year=1820
}}
|basionyms=
|synonyms=
|hierarchy=Asteraceae;Asteraceae tribe Heliantheae;Asteraceae (tribe Heliantheae) subtribe Melampodiinae;Acanthospermum
|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 Melampodiinae]]</div><div class="higher-taxon"><small>genus</small>[[Acanthospermum]]</div></div>
|etymology=Greek acantha, prickle, and sperma, seed, alluding to prickly “fruits”
|volume=Volume 21
|mention_page=page 33
|treatment_page=page 36
}}<!--

--><span class="statement" id="st-d0_s0" data-properties="whole-organism atypical some measurement;whole-organism some measurement;whole-organism duration"><b>Annuals </b>(sometimes persisting), 10–60 (–120) cm.</span> <span class="statement" id="st-d0_s1" data-properties="stem orientation"><b>Stems </b>erect to ± prostrate (repeatedly “forked”).</span> <span class="statement" id="st-d0_s2" data-properties=""><b>Leaves </b>cauline;</span> <span class="statement" id="st-d0_s3" data-properties="">opposite;</span> <span class="statement" id="st-d0_s4" data-properties="leaf position;leaf arrangement;leaf architecture;leaf architecture">petiolate or ± sessile;</span> <span class="statement" id="st-d0_s5" data-properties="blade shape;blade shape;blade shape;blade shape;ultimate margin shape;ultimate margin shape;face pubescence;face relief;face pubescence;face pubescence">blades mostly elliptic to deltate, rhombic, or ovate, sometimes lyrate, ultimate margins entire or toothed, faces usually pilosulous to sericeous or scabrellous, sometimes glabrate or glabrescent, usually glanddotted.</span> <span class="statement" id="st-d0_s6" data-properties="head architecture or arrangement;head atypical quantity;head quantity"><b>Heads </b>radiate, 1 (–3) in “forks” of branches (terminal, appearing axillary by sympodial growth).</span> <span class="statement" id="st-d0_s7" data-properties=""><b>Involucres </b>± hemispheric, 3–5 mm diam.</span> <span class="statement" id="st-d0_s8" data-properties="involucre shape;involucre diameter">(becoming ± rotate in fruit).</span> <span class="statement" id="st-d0_s9" data-properties="phyllary duration;phyllary life cycle;phyllary quantity;series quantity"><b>Phyllaries </b>persistent (outer) or falling, 10–13 in 2 series (outer 4–6 herbaceous, inner 5–8 each investing a ray ovary, enlarging in fruit to form a perigynium, shed with enclosed cypsela).</span> <span class="statement" id="st-d0_s10" data-properties="receptacle shape;receptacle architecture"><b>Receptacles </b>convex, paleate (paleae cuneate to spatulate, ± conduplicate or flattish, membranous).</span> <span class="statement" id="st-d0_s11" data-properties="ray-floret quantity;ray-floret architecture;ray-floret reproduction"><b>Ray-</b>florets 5–8, pistillate, fertile;</span> <span class="statement" id="st-d0_s12" data-properties="corolla coloration">corollas yellowish (tubes shorter than to equaling laminae, laminae ovate to elliptic or linear).</span> <span class="statement" id="st-d0_s13" data-properties="disc-floret atypical quantity;disc-floret quantity;disc-floret architecture"><b>Disc-</b>florets 3–8 (–12+), functionally staminate;</span> <span class="statement" id="st-d0_s14" data-properties="corolla coloration;tube height or length or size;throat shape;lobe quantity;lobe shape">corollas yellowish, tubes shorter than funnelform or campanulate throats, lobes 5, deltate.</span> <span class="statement" id="st-d0_s15" data-properties="perigynium texture;perigynium architecture"><b>Cypselae </b>each enclosed within and shed with an often hardened, ± prickly perigynium (the ultimate “fruits” plumply ellipsoid to fusiform, or ± compressed);</span> <span class="statement" id="st-d0_s16" data-properties="">pappi 0 or rudimentary.</span> <span class="statement" id="st-d0_s17" data-properties="pappus presence;pappus prominence;x chromosome quantity">x = 11.</span><!--

-->{{Treatment/Body
|distribution=mostly tropical to warm-temperate New World;also  in Old World
|introduced=true
|discussion=<p>Species 6 (3 in the flora).</p>
|tables=
|references={{Treatment/Reference
|id=blake1921a
|text=Blake, S. F. 1921. Revision of the genus Acanthospermum. Contr. U.S. Natl. Herb. 20: 383–392.
}}
}}<!--

--><div class="treatment-key">
==Key==
<div class="treatment-key-group">
  
{| class="wikitable fna-keytable"
|-id=key-0-1
|1
|Fruits 7–9+ mm, 5–7-ribbed, terminal spines 0
|[[Acanthospermum australe|Acanthospermum australe]]
|-id=key-0-1
|1
|Fruits 2–6 mm, 3-ribbed or not notably ribbed, terminal spines 2
|[[#key-0-2| > 2]]
|-id=key-0-2
|2
|Leaf blades rhombic-ovate to obovate, (20–)40–120(–150+) mm; fruits not notably ribbed, prickles ± scattered
|[[Acanthospermum hispidum|Acanthospermum hispidum]]
|-id=key-0-2
|2
|Leaf blades ovate to lyrate, 10–30(–45) mm; fruits usually 3-ribbed, prickles mostly along 2 ribs and around apices
|[[Acanthospermum humile|Acanthospermum humile]]
|}
</div></div><!--

-->{{#Taxon:
name=Acanthospermum
|author=John L. Strother
|authority=Schrank
|rank=genus
|parent rank=subtribe
|synonyms=
|basionyms=
|family=Asteraceae
|illustrator=Barbara Alongi
|illustration copyright=Flora of North America Association
|distribution=mostly tropical to warm-temperate New World;also  in Old World
|introduced=true
|reference=blake1921a
|publication title=Pl. Rar. Hort. Monac.
|publication year=1820
|special status=
|source xml=https://bibilujan@bitbucket.org/aafc-mbb/fna-fine-grained-xml.git/src/84153f6d59a0a91d69695978a64cee7560374f8e/V19-20-21/V21_70.xml
|tribe=Asteraceae tribe Heliantheae
|subtribe=Asteraceae (tribe Heliantheae) subtribe Melampodiinae
|genus=Acanthospermum
|blade shape=lyrate;mostly elliptic;deltate rhombic or ovate
|corolla coloration=yellowish;yellowish
|disc-floret architecture=staminate
|disc-floret atypical quantity=8;12
|disc-floret quantity=3;8
|face pubescence=glabrescent;glabrate;usually pilosulous;sericeous
|face relief=scabrellous
|head architecture or arrangement=radiate
|head atypical quantity=1;3
|head quantity=1
|involucre diameter=3mm;5mm
|involucre shape=hemispheric
|leaf architecture=sessile;petiolate
|leaf arrangement=opposite
|leaf position=cauline
|lobe quantity=5
|lobe shape=deltate
|pappus presence=absent
|pappus prominence=rudimentary
|perigynium architecture=prickly
|perigynium texture=hardened
|phyllary duration=persistent
|phyllary life cycle=falling
|phyllary quantity=10;13
|ray-floret architecture=pistillate
|ray-floret quantity=5;8
|ray-floret reproduction=fertile
|receptacle architecture=paleate
|receptacle shape=convex
|series quantity=2
|stem orientation=erect;more or less prostrate
|throat shape=campanulate
|tube height or length or size=shorter
|ultimate margin shape=toothed;entire
|whole-organism atypical some measurement=60cm;120cm
|whole-organism duration=annual
|whole-organism some measurement=10cm;60cm
|x chromosome quantity=11
}}<!--

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