View source for Opuntia macrorhiza

{{Treatment/ID
|accepted_name=Opuntia macrorhiza
|accepted_authority=Engelmann
|publications={{Treatment/Publication
|title=Boston J. Nat. Hist.
|place=6: 206. 1850
|year=1850
}}
|common_names=Western pricklypear
|basionyms=
|synonyms={{Treatment/ID/Synonym
|name=Opuntia compressa var. macrorhiza
|authority=(Engelmann) L. D. Benson
|rank=variety
}} {{Treatment/ID/Synonym
|name=Opuntia mesacantha var. acrorhiza
|authority=(Engelmann) J. M. Coulter
|rank=variety
}}
|hierarchy=Cactaceae;Cactaceae subfam. Opuntioideae;Opuntia;Opuntia macrorhiza
|hierarchy_nav=<div class="higher-taxa"><div class="higher-taxon"><small>family</small>[[Cactaceae]]</div><div class="higher-taxon"><small>subfamily</small>[[Cactaceae subfam. Opuntioideae]]</div><div class="higher-taxon"><small>genus</small>[[Opuntia]]</div><div class="higher-taxon"><small>species</small>[[Opuntia macrorhiza]]</div></div>
|volume=Volume 4
|mention_page=page 131
|treatment_page=
}}<!--

--><span class="statement" id="st-undefined" data-properties=""><b>Shrubs,</b> forming clumps, 7.5–16 cm, sometimes from tuberlike rootstocks. <b>Stem</b> segments not easily detached, dark dull green, often cross wrinkled when stressed, flattened, obovate to circular, 5–11 × 3.5–7.5 cm, fleshy (to flabby and cross wrinkled when stressed), tuberculate, glaucous; areoles 5–6(–8) per diagonal row across midstem segment, oval to subcircular, 2–4 mm diam.; wool tan. <b>Spines</b> (0–)1–4 per areole, usually in distal areoles, erect to spreading, white to red-brown, acicular, straight, terete or 1 flattened, ± stout (0.5 mm diam. at base), longest to 60 mm. <b>Glochids</b> in dense tuft, pale yellow, tan to red-brown, aging brown, to 5 mm. <b>Flowers</b>: inner tepals yellow with red basal portions, 25–40 mm; filaments pale yellow; anthers yellow; style white; stigma lobes cream to yellowish. <b>Fruits</b> green to yellowish to dull red, stipitate, elongate-obovoid, 25–40 × 15–28 mm, fleshy, glabrous; areoles 16–28. <b>Seeds</b> tan, subcircular, 4–5 mm, thickish, warped; girdle broad, protruding to 0.5 mm. <b>2n</b> = 44.</span><!--

-->{{Treatment/Body
|phenology=Flowering late spring (May–Jun).
|habitat=Plains, chaparral, grassy woodlands, coniferous forests, sandy to loamy soils
|elevation=100-2300 m
|distribution=Ariz.;Ark.;Colo.;Kans.;Mo.;N.Mex.;Okla.;Tex.;Utah;Mexico (Chihuahua).
|discussion=<p><i>Opuntia macrorhiza</i> hybridizes with the hexaploid <i>O. engelmannii</i> (apparently <i></i>var.<i> lindheimeri</i>) forming the pentaploid O. ×edwardsii V. E. Grant & K. A. Grant. This hybrid is a small subshrub, 20–40 cm, with a mixture of widely spaced, unequal glochids and closely spaced, shorter glochids. Its major spines are gray, and its tepals are yellow or yellow with red bases. Those characteristics are similar to one parent or the intermediate of the two putative parents reported from Blanco and Guadalupe counties, central Texas.</p>
|tables=
|references=
}}<!--

--><!--

-->{{#Taxon:
name=Opuntia macrorhiza
|authority=Engelmann
|rank=species
|parent rank=genus
|synonyms=Opuntia compressa var. macrorhiza;Opuntia mesacantha var. acrorhiza
|basionyms=
|family=Cactaceae
|phenology=Flowering late spring (May–Jun).
|habitat=Plains, chaparral, grassy woodlands, coniferous forests, sandy to loamy soils
|elevation=100-2300 m
|distribution=Ariz.;Ark.;Colo.;Kans.;Mo.;N.Mex.;Okla.;Tex.;Utah;Mexico (Chihuahua).
|reference=None
|publication title=Boston J. Nat. Hist.
|publication year=1850
|special status=
|source xml=https://jpend@bitbucket.org/aafc-mbb/fna-data-curation.git/src/f50eec43f223ca0e34566be0b046453a0960e173/coarse_grained_fna_xml/V4/V4_245.xml
|subfamily=Cactaceae subfam. Opuntioideae
|genus=Opuntia
|species=Opuntia macrorhiza
}}<!--

-->[[Category:Treatment]][[Category:Opuntia]]