View source for Echinocactus

{{Treatment/ID
|accepted_name=Echinocactus
|accepted_authority=Link & Otto
|publications={{Treatment/Publication
|title=Verh. Vereins Beförd. Gartenbaues Königl. Preuss. Staaten
|place=3: 420. 1827
|year=1827
}}
|common_names=Barrel cactus;eagle-claw cactus;echinocactus
|basionyms=
|synonyms={{Treatment/ID/Synonym
|name=Homalocephala
|authority=Britton & Rose
}}
|hierarchy=Cactaceae;Cactaceae subfam. Cactoideae;Echinocactus
|hierarchy_nav=<div class="higher-taxa"><div class="higher-taxon"><small>family</small>[[Cactaceae]]</div><div class="higher-taxon"><small>subfamily</small>[[Cactaceae subfam. Cactoideae]]</div><div class="higher-taxon"><small>genus</small>[[Echinocactus]]</div></div>
|etymology=Greek echinos, hedgehog, an d Cactus, an old genus name
|volume=Volume 4
|mention_page=page 97, 207
|treatment_page=page 188
}}<!--

--><span class="statement" id="st-undefined" data-properties=""><b>Plants </b>erect, branched or unbranched, forming compact mounds of 30+ branches, not deep-seated in substrate (or deep-seated in <i>E. texensis</i> and, if plants immature or at high altitude, in <i>E. horizonthalonius</i>). <b>Roots</b> diffuse or short taproots. <b>Stems</b> unsegmented, gray-blue, gray-green, yellow-green, or grass green, flat-topped spheric to short cylindric, 4–40(–45)[–250] × 8–30[–80] cm, apical region appearing copiously woolly (shortly velvety in <i>E. texensis</i>) [glabrous]; ribs (7–)8–27[–60+], very prominent, straight (or only slightly undulate), sometimes helically curving around stems, broadly rounded to nearly keeled, rib crests uninterrupted or ± constricted between areoles; areoles widely spaced or confluent with age, nearly circular to oblong, with fertile portion as short, broad adaxial prolongation confluent with spine cluster; areolar glands absent; cortex and pith hard, not mucilaginous. <b>Spines</b> (5–)7–19 per areole, straw colored, pink, red, gray, tan, or brown, conspicuously annulate-ridged, rigid, stiff; radial spines 5–14 per areole, straight to curved, 2–5 cm; central spines 1–4 per areole, straight to curved, terete, flattened, or abaxially ridged. <b>Flowers</b> diurnal, near stem apex, near adaxial edges of short adaxial extensions of areoles, broadly funnelform to nearly salverform (more narrowly funnelform in <i>E. texensis</i>); outer tepals margins entire, apically spinose; inner tepals yellow or pink to magenta, 2.4–3.2 × 0.3–1.5 cm, margins entire, serrate, toothed, or erose; ovary scaly, spineless, copiously woolly, with white or pale tan hairs from areoles hiding ovary and flower tube at anthesis; scales 8–60, margins entire or fimbriate, spine-tipped; stigma lobes 6–14(–17), yellow, pink, or olive, 1–4.5 mm. <b>Fruits</b> either indehiscent or rupturing irregularly, or tardily dehiscent through basal abscission pore, whitish tan to pinkish (bright red in <i>E. texensis</i>), spheric to ovoid or ovoid-cylindric, 10–50 × 10–40[–100] mm, usually nearly dry (strongly succulent in <i>E. texensis</i>), many scaled; axils of scales copiously woolly (wool hiding surface of fruits except in <i>E. texensis</i>), spineless, distal scales spine-tipped; pulp red; floral remnant persistent. <b>Seeds</b> reddish brown to black, spheric, or subreniform to obovoid, 2.4–4.7 mm, shiny or dull; testa cells convex or flat. <b>x</b> = 11.</span><!--

-->{{Treatment/Body
|distribution=sw United States;Mexico.
|discussion=<p>Species 6 (3 in the flora).</p><!--
--><p>With the exception of the much-branched <i>Echinocactus polycephalus</i>, species of <i>Echinocactus</i> in the flora area are almost never branched, and will die instead of producing a lateral bud when the apex is injured. Smaller than normal fruits of <i>Echinocactus</i> are usually aborted and hollow as the result of infestation by insect larvae (M. Chamberland, pers. comm.).</p>
|tables=
|references=
}}<!--

--><div class="treatment-key">
==Key==
<div class="treatment-key-group">
  
{| class="wikitable fna-keytable"
|-id=key-0-1
|1
|Inner tepals yellow; plants many branched (except in very young adults); w Arizona, s Nevada, se California, Mexico
|[[Echinocactus polycephalus|Echinocactus polycephalus]]
|-id=key-0-1
|1
|Inner tepals pink, magenta, or proximally red and distally pink; plants unbranched (rarely few branched); c to s Arizona, New Mexico, Texas, Mexico
|[[#key-0-2| > 2]]
|-id=key-0-2
|2
|Ribs (7-)8(-9), crests broadly rounded, never keeled; stems flat-topped or hemispheric to stoutly cylindric; fruit surfaces hidden by abundant wool at maturity; spines and bract tips glabrous (use lens)
|[[Echinocactus horizonthalonius|Echinocactus horizonthalonius]]
|-id=key-0-2
|2
|Ribs 13-27, crests narrow, ± keeled; stems flat-topped to hemispheric; fruit surfaces exposed at maturity, bright red; spines and bract tips densely puberulent with ± matted, strap-shaped, unicellular hairs (use at least 8× lens)
|[[Echinocactus texensis|Echinocactus texensis]]
|}
</div></div><!--

-->{{#Taxon:
name=Echinocactus
|author=Allan D. Zimmerman;Bruce D. Parfitt
|authority=Link & Otto
|rank=genus
|parent rank=subfamily
|synonyms=Homalocephala
|basionyms=
|family=Cactaceae
|distribution=sw United States;Mexico.
|reference=None
|publication title=Verh. Vereins Beförd. Gartenbaues Königl. Preuss. Staaten
|publication year=1827
|special status=
|source xml=https://jpend@bitbucket.org/aafc-mbb/fna-data-curation.git/src/f6b125a955440c0872999024f038d74684f65921/coarse_grained_fna_xml/V4/V4_353.xml
|subfamily=Cactaceae subfam. Cactoideae
|genus=Echinocactus
}}<!--

-->[[Category:Treatment]][[Category:Cactaceae subfam. Cactoideae]]