View source for Polypodium hesperium

{{Treatment/ID
|accepted_name=Polypodium hesperium
|accepted_authority=Maxon
|publications={{Treatment/Publication
|title=Proc. Biol. Soc. Wash.
|place=13: 200. 1900
|year=1900
}}
|common_names=Western polypody
|basionyms=
|synonyms={{Treatment/ID/Synonym
|name=Polypodium prolongilobum
|authority=Clute
}} {{Treatment/ID/Synonym
|name=Polypodium vulgare subsp. columbianum
|authority=(Gilbert) Hultén
}} {{Treatment/ID/Synonym
|name=Polypodium vulgare var. columbianum
|authority=Gilbert
}} {{Treatment/ID/Synonym
|name=Polypodium vulgare var. hesperium
|authority=(Maxon) A. Nelson & J. F. Macbride
}}
|hierarchy=Polypodiaceae;Polypodium;Polypodium hesperium
|hierarchy_nav=<div class="higher-taxa"><div class="higher-taxon"><small>family</small>[[Polypodiaceae]]</div><div class="higher-taxon"><small>genus</small>[[Polypodium]]</div><div class="higher-taxon"><small>species</small>[[Polypodium hesperium]]</div></div>
|volume=Volume 2
|mention_page=
|treatment_page=
}}<!--

--><span class="statement" id="st-undefined" data-properties=""><b>Stems </b>occasionally whitish pruinose, slender to moderately stout, to 6 mm diam., acrid- to sweet-tasting: scales concolored, brown or slightly mottled, often darker near point of attachment, lanceolate, usually symmetric, margins entire to denticulate. <b>Leaves</b> to 35 cm. <b>Petiole</b> slender, to 1.5 mm diam. <b>Blade</b> oblong to lanceolate-ovate, occasionally deltate, pinnatifid, usually widest at or near middle, to 7 cm wide, herbaceous to somewhat leathery; rachis sparsely scaly to glabrescent abaxially, glabrous adaxially; scales linear-lanceolate, usually less than 6 cells wide. <b>Segments</b> oblong to linear-lanceolate, less than 12 mm wide; margins entire to crenulate or obscurely serrate; apex obtuse to acute; midrib glabrous adaxially. <b>Venation</b> free. <b>Sori</b> midway between margin and midrib, less than 3 mm diam., oval when immature. <b>Sporangiasters</b> absent. <b>Spores</b> more than 58 µm, rugose to verrucose or tuberculate, surface projections commonly less than 3 µm. <b>2n</b> = 148.</span><!--

-->{{Treatment/Body
|phenology=Sporulating summer–fall.
|habitat=Cracks and ledges on cliffs, on a variety of noncalcareous substrates, rarely on limestone
|elevation=300–3500 m.
|distribution=B.C.;Ariz.;Calif.;Colo.;Idaho;Mont.;Nev.;N.Mex.;Oreg.;Utah;Wash.;Mexico in Chihuahua;Baja California.
|discussion=<p>Using morphologic and chromosomal data, F. A. Lang (1971) proposed that <i>Polypodium hesperium</i> originated through allotetraploidy involving <i>P. glycyrrhiza</i> and <i>P. amorphum</i>, a hypothesis recently supported by electrophoretic studies (C. H. Haufler, M. D. Windham, and E. W. Rabe, unpublished). Variations in spore surface morphology and banding patterns observed in isozyme studies indicate that <i>P. hesperium</i> may have originated more than once from different individuals of the same species. Some collections of <i>P. hesperium</i> can be mistaken for <i>P. glycyrrhiza</i>, but the latter species is easily distinguished by its pubescent rachises, linear blade scales, and smaller spores (less than 58 µm). Although <i>P. amorphum</i> has sporangiasters and <i>P. hesperium</i> lacks them, misshapen sporangia in <i>P. hesperium</i> can mimic these distinctive soral structures. Therefore, it is often necessary to use a combination of soral, stem scale, and blade scale features (discussed in the key) to separate <i>P. hesperium</i> from <i>P. amorphum</i>. Hybridization occurs between <i>P. hesperium</i> and each of its progenitor diploids to form triploid individuals with misshapen spores (F. A. Lang 1971). Rare, sterile, tetraploid hybrids with <i>P. saximontanum</i> have also been detected (M. D. Windham, unpublished).</p>
|tables=
|references=
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-->{{#Taxon:
name=Polypodium hesperium
|author=
|authority=Maxon
|rank=species
|parent rank=genus
|synonyms=Polypodium prolongilobum;Polypodium vulgare subsp. columbianum;Polypodium vulgare var. columbianum;Polypodium vulgare var. hesperium
|basionyms=
|family=Polypodiaceae
|phenology=Sporulating summer–fall.
|habitat=Cracks and ledges on cliffs, on a variety of noncalcareous substrates, rarely on limestone
|elevation=300–3500 m.
|distribution=B.C.;Ariz.;Calif.;Colo.;Idaho;Mont.;Nev.;N.Mex.;Oreg.;Utah;Wash.;Mexico in Chihuahua;Baja California.
|reference=None
|publication title=Proc. Biol. Soc. Wash.
|publication year=1900
|special status=
|source xml=https://jpend@bitbucket.org/aafc-mbb/fna-data-curation.git/src/f6b125a955440c0872999024f038d74684f65921/coarse_grained_fna_xml/V2/V2_156.xml
|genus=Polypodium
|species=Polypodium hesperium
}}<!--

-->[[Category:Treatment]][[Category:Polypodium]]