View source for Boechera retrofracta

{{Treatment/ID
|accepted_name=Boechera retrofracta
|accepted_authority=(Graham) Á. Löve & D. Löve
|publications={{Treatment/Publication
|title=Taxon
|place=31: 125. 1982
|year=1982
}}
|basionyms={{Treatment/ID/Basionym
|name=Arabis retrofracta
|authority=Graham
|publication_title=Edinburgh New Philos. J.
|publication_place=7: 344. 1829
}}
|synonyms={{Treatment/ID/Synonym
|name=Arabis arcuata var. secunda
|authority=(Howell) B. L. Robinson ex S. Watson
}} {{Treatment/ID/Synonym
|name=Arabis exilis
|authority=A. Nelson
}} {{Treatment/ID/Synonym
|name=Arabis holboellii var. retrofracta
|authority=(Graham) Rydberg
}} {{Treatment/ID/Synonym
|name=Arabis holboellii var. secunda
|authority=(Howell) Jepson
}} {{Treatment/ID/Synonym
|name=Arabis lignipes
|authority=Howell
}} {{Treatment/ID/Synonym
|name=Arabis retrofracta var. multicaulis
|authority=B. Boivin
}} {{Treatment/ID/Synonym
|name=Arabis secunda
|authority=Greene
}} {{Treatment/ID/Synonym
|name=Arabis sparsiflora subsp. secunda
|authority=(Howell) Piper
}} {{Treatment/ID/Synonym
|name=Arabis tenuis
|authority=(Hornemann) Á. Löve & D. Löve
}} {{Treatment/ID/Synonym
|name=Boechera exilis
|authority=unknown
}} {{Treatment/ID/Synonym
|name=Boechera holboellii var. secunda
|authority=(Howell) Dorn
}}
|hierarchy=Brassicaceae;Brassicaceae tribe Boechereae;Boechera;Boechera retrofracta
|hierarchy_nav=<div class="higher-taxa"><div class="higher-taxon"><small>family</small>[[Brassicaceae]]</div><div class="higher-taxon"><small>tribe</small>[[Brassicaceae tribe Boechereae]]</div><div class="higher-taxon"><small>genus</small>[[Boechera]]</div><div class="higher-taxon"><small>species</small>[[Boechera retrofracta]]</div></div>
|volume=Volume 7
|mention_page=page 350, 352, 354, 356, 371, 374, 381, 393, 397, 398, 400, 401
|treatment_page=page 402
}}<!--

--><span class="statement" id="st-undefined" data-properties=""><b>Biennials </b>or perennials; short-lived; sexual; caudex present or absent. <b>Stems</b> usually 1 per caudex branch, arising from center of rosette near ground surface, 1.5–7(–10.5) dm, densely pubescent proximally, trichomes short-stalked, 2–8-rayed, 0.1–0.2 mm, sparsely pubescent distally. <b>Basal</b> leaves: blade oblanceolate, 2–7 mm wide, margins entire or shallowly dentate, sometimes ciliate at petiole base, surfaces densely pubescent, trichomes short-stalked, 5–10-rayed, 0.05–0.2 mm. <b>Cauline</b> leaves: 15–40, concealing stem proximally; blade auricles 0.5–2.5 mm or, rarely, absent, surfaces of distalmost leaves pubescent. <b>Racemes</b> 15–80(–140)-flowered, usually unbranched. <b>Fruiting</b> pedicels reflexed, abruptly recurved at base, otherwise usually straight, 7–12(–18) mm, pubescent, trichomes appressed, branched. <b>Flowers</b> pendent at anthesis; sepals pubescent; petals white to lavender, 4–8 × 0.8–2.2 mm, glabrous; pollen ellipsoid. <b>Fruits</b> strongly reflexed, usually appressed to rachis, sometimes somewhat secund, straight, edges parallel, 3.5–9 cm × 0.9–1.8 mm; valves glabrous or sparsely pubescent throughout; ovules 60–116 per ovary; style 0.5–2 mm. <b>Seeds</b> uniseriate, 1–1.4 × 0.9–1.2 mm; wing continuous, to 0.1 mm wide. <b>2n</b> = 14.</span><!--

-->{{Treatment/Body
|phenology=Flowering Apr–Aug.
|habitat=Rock outcrops, open hillsides, gravel bars and sandy banks in grassland, sagebrush, oak woodlands, and open conifer forests
|elevation=300-3300 m
|distribution=Alta.;B.C.;Man.;N.W.T.;Ont.;Que.;Sask.;Alaska;Calif.;Idaho;Mich.;Mont.;Nev.;Oreg.;Utah;Wash.;Wyo.
|discussion=<p>Though often treated as a variety of <i>Arabis</i> (<i>Boechera</i>) holboellii (e.g., R. C. Rollins 1993; G. A. Mulligan 1996; N. H. Holmgren 2005b), <i>B. retrofracta</i> is easily distinguished from that species by having narrower (0.9–1.8 versus 2–2.5 mm), mostly non-secund fruits that are almost always appressed to rachises. The two taxa have allopatric distributions, with <i>B. retrofracta</i> found on the North American continent (mostly west of the Great Plains) and <i>B. holboellii</i> apparently confined to Greenland. <i>Boechera retrofracta</i> has formed hybrids with at least 12 other species. Besides differing in macromorphological characters, all those hybrids are distinct from <i>B. retrofracta</i> in the strict sense in having wider (20–30 versus 13–16 µm), spheroid pollen grains with asymmetric colpi.</p><!--
--><p><i>Arabis</i> kochii Blankinship is an illegitimate name, sometimes found in synonymy with <i>Boechera retrofracta</i>.</p>
|tables=
|references=
}}<!--

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-->{{#Taxon:
name=Boechera retrofracta
|author=
|authority=(Graham) Á. Löve & D. Löve
|rank=species
|parent rank=genus
|synonyms=Arabis arcuata var. secunda;Arabis exilis;Arabis holboellii var. retrofracta;Arabis holboellii var. secunda;Arabis lignipes;Arabis retrofracta var. multicaulis;Arabis secunda;Arabis sparsiflora subsp. secunda;Arabis tenuis;Boechera exilis;Boechera holboellii var. secunda
|basionyms=Arabis retrofracta
|family=Brassicaceae
|phenology=Flowering Apr–Aug.
|habitat=Rock outcrops, open hillsides, gravel bars and sandy banks in grassland, sagebrush, oak woodlands, and open conifer forests
|elevation=300-3300 m
|distribution=Alta.;B.C.;Man.;N.W.T.;Ont.;Que.;Sask.;Alaska;Calif.;Idaho;Mich.;Mont.;Nev.;Oreg.;Utah;Wash.;Wyo.
|reference=None
|publication title=Taxon
|publication year=1982
|special status=
|source xml=https://jpend@bitbucket.org/aafc-mbb/fna-data-curation.git/src/f6b125a955440c0872999024f038d74684f65921/coarse_grained_fna_xml/V7/V7_581.xml
|tribe=Brassicaceae tribe Boechereae
|genus=Boechera
|species=Boechera retrofracta
}}<!--

-->[[Category:Treatment]][[Category:Boechera]]