View source for Polystemma cordifolium

{{Treatment/ID
|accepted_name=Polystemma cordifolium
|accepted_authority=(A. Gray) McDonnell & Fishbein
|publications={{Treatment/Publication
|title=Phytologia
|place=99: 86. 2017
|year=2017
}}
|common_names=Sonoran milkweed vine
|special_status={{Treatment/ID/Special_status
|code=F
|label=Illustrated
}}
|basionyms={{Treatment/ID/Basionym
|name=Rothrockia cordifolia
|authority=A. Gray
|rank=species
|publication_title=Proc. Amer. Acad. Arts
|publication_place=20: 295.  1885
}}
|synonyms={{Treatment/ID/Synonym
|name=Matelea cordifolia
|authority=(A. Gray) Woodson
|rank=species
}}
|hierarchy=Apocynaceae;Polystemma;Polystemma cordifolium
|hierarchy_nav=<div class="higher-taxa"><div class="higher-taxon"><small>family</small>[[Apocynaceae]]</div><div class="higher-taxon"><small>genus</small>[[Polystemma]]</div><div class="higher-taxon"><small>species</small>[[Polystemma cordifolium]]</div></div>
|volume=Volume 14
|mention_page=
|treatment_page=
}}<!--

--><span class="statement" id="st-undefined" data-properties=""><b>Stems:</b> bark tan, corky, shallowly furrowed. <b>Leaves</b>: 1 stipular colleter on each side of petiole; petiole 1–4.5 cm; blade ovate, 2.5–8 × 2–6 cm, chartaceous, base deeply cordate, laminar colleters 2–4, margins planar, apex acute to acuminate, venation pinnipalmate, surfaces densely puberulent to hirsute, paler abaxially. <b>Inflorescences</b> umbelliform or racemiform, 4–6-flowered; peduncle 1–4 cm. <b>Pedicels</b> 5–10 mm. <b>Flowers</b>: calyx lobes lanceolate-ovate, apices acute, 3–5 mm, hirsutulous; corolla tube 3–4 mm, lobes ascending, sometimes twisted, linear-lanceolate to oblong, 6–12 mm, glabrous; corona segments basally connate and united to base of column, green, laminar, fleshy, ovate with minute teeth, much shorter than gynostegium; gynostegium sessile; style apex prolonged into bifid beak, papillose. <b>Follicles</b> 4.5–13.2 × 1–1.5 cm, apically attenuate. <b>Seeds</b> 100–150, reddish brown, 6 × 4 mm, granulate-tuberculate; coma white, 3–4 cm.</span><!--

-->{{Treatment/Body
|phenology=Flowering Jul–Sep; fruiting Oct–Mar.
|habitat=Arroyos, canyons, hills, slopes, plains, rock outcrops, granite, sandy and gravelly soils, desert scrub.
|elevation=200–300 m.
|distribution=Ariz.;Mexico (Baja California;Baja California Sur;Sonora).
|discussion=<p>Polystemma cordifolium is widely distributed in the drier parts of the Sonoran Desert and reaches its northern limit in Organ Pipe Cactus National Monument (Pima County), where it may no longer be extant (R. S. Felger et al. 2014). It should be considered to be of conservation concern in the flora area.</p>
|tables=
|references=
}}<!--

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-->{{#Taxon:
name=Polystemma cordifolium
|authority=(A. Gray) McDonnell & Fishbein
|rank=species
|parent rank=genus
|synonyms=Matelea cordifolia
|basionyms=Rothrockia cordifolia
|family=Apocynaceae
|phenology=Flowering Jul–Sep; fruiting Oct–Mar.
|habitat=Arroyos, canyons, hills, slopes, plains, rock outcrops, granite, sandy and gravelly soils, desert scrub.
|elevation=200–300 m.
|distribution=Ariz.;Mexico (Baja California;Baja California Sur;Sonora).
|reference=None
|publication title=Phytologia
|publication year=2017
|special status=Illustrated
|source xml=
|genus=Polystemma
|species=Polystemma cordifolium
}}<!--

-->[[Category:Treatment]][[Category:Polystemma]]