View source for Crataegus rivularis

{{Treatment/ID
|accepted_name=Crataegus rivularis
|accepted_authority=Nuttall in J. Torrey and A. Gray
|publications={{Treatment/Publication
|title=in J. Torrey and A. Gray, Fl. N. Amer.
|place=1: 464. 1840
|year=1840
}}
|common_names=Mountain river hawthorn
|special_status={{Treatment/ID/Special_status
|code=E
|label=Endemic
}}{{Treatment/ID/Special_status
|code=F
|label=Illustrated
}}
|basionyms=
|synonyms=
|hierarchy=Rosaceae;Rosaceae subfam. Amygdaloideae;Rosaceae tribe Gillenieae;Crataegus;Crataegus sect. Douglasia;Crataegus (sect. Douglasia) ser. Cerrones;Crataegus rivularis
|hierarchy_nav=<div class="higher-taxa"><div class="higher-taxon"><small>family</small>[[Rosaceae]]</div><div class="higher-taxon"><small>subfamily</small>[[Rosaceae subfam. Amygdaloideae]]</div><div class="higher-taxon"><small>tribe</small>[[Rosaceae tribe Gillenieae]]</div><div class="higher-taxon"><small>genus</small>[[Crataegus]]</div><div class="higher-taxon"><small>section</small>[[Crataegus sect. Douglasia]]</div><div class="higher-taxon"><small>series</small>[[Crataegus (sect. Douglasia) ser. Cerrones]]</div><div class="higher-taxon"><small>species</small>[[Crataegus rivularis]]</div></div>
|volume=Volume 9
|mention_page=page 509
|treatment_page=page 510
}}<!--

--><span class="statement" id="st-undefined" data-properties=""><b>Shrubs </b>or trees, 30–50 dm. <b>Stems</b>: twigs: new growth greenish, sparsely pubescent, early glabrescent, 1–2-years old often red-purple; bark on younger 2–5 cm thick branches dark gray-brown, sometimes copper-colored; thorns on twigs straight or ± recurved, 2-years old black or purple-black, glossy, fine, 1.5–4 cm. <b>Leaves</b>: petiole 1–2.5 cm, glabrous; blade elliptic to narrowly elliptic, 3–8 cm, length 2+ times width, thin, base cuneate, lobes 0 or small apiculi at ends of some vein tips, margins serrate, teeth numerous, usually acute, fine to coarse, venation semicamptodromous, veins 4 or 5 per side, larger often branched proximal to ends, apex acute, abaxial surface glabrous, adaxial appressed-strigose young. <b>Inflorescences</b> 6–12-flowered; branches glandular-punctate; bracteoles early caducous, usually present, margins sessile-glandular. <b>Flowers</b> 14–17 mm diam.; sepals broadly deltate, 6–8 mm, margins entire, apex narrow, glabrous; stamens 10, anthers pink, sometimes ivory; styles 3–5. <b>Pomes</b> deep red (mid Aug), black or blackish purple mature, suborbicular, 10 mm diam.; sepals ± erect to strongly outcurved or ± patent, 2–3 mm; pyrenes 3 or 4, sides eroded.</span><!--

-->{{Treatment/Body
|phenology=Flowering mid May–early Jun; fruiting Aug–Sep.
|habitat=Intermontane streamsides, ditches, flood plains
|elevation=1300–2300 m
|distribution=Ariz.;Colo.;Idaho;Nev.;N.Mex.;Utah;Wyo.
|discussion=<p><i>Crataegus rivularis</i> is most abundant in intermontane Colorado and Utah and is one of two hawthorns found in Arizona; it is rare in <i>Nevada</i>. There are reports from northwestern Texas (for example, D. S. Correll and M. C. Johnston 1970); they have not been verified. <i>Crataegus rivularis</i> is one of the more common woody species of mesic, valley bottom intermontane habitats. The species flowers early.</p><!--
--><p><i>Crataegus rivularis</i> is superficially similar to the more or less sympatric, less common, <i>C. saligna</i>; it has larger leaves with fewer veins, larger flowers with ten stamens, and larger pomes. It differs from <i>C. erythropoda</i> little other than in leaf shape and ripe fruit color.</p>
|tables=
|references=
}}<!--

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-->{{#Taxon:
name=Crataegus rivularis
|authority=Nuttall in J. Torrey and A. Gray
|rank=species
|parent rank=series
|synonyms=
|basionyms=
|family=Rosaceae
|phenology=Flowering mid May–early Jun; fruiting Aug–Sep.
|habitat=Intermontane streamsides, ditches, flood plains
|elevation=1300–2300 m
|distribution=Ariz.;Colo.;Idaho;Nev.;N.Mex.;Utah;Wyo.
|reference=None
|publication title=in J. Torrey and A. Gray, Fl. N. Amer.
|publication year=1840
|special status=Endemic;Illustrated
|source xml=https://jpend@bitbucket.org/aafc-mbb/fna-data-curation.git/src/f50eec43f223ca0e34566be0b046453a0960e173/coarse_grained_fna_xml/V9/V9_859.xml
|subfamily=Rosaceae subfam. Amygdaloideae
|tribe=Rosaceae tribe Gillenieae
|genus=Crataegus
|section=Crataegus sect. Douglasia
|series=Crataegus (sect. Douglasia) ser. Cerrones
|species=Crataegus rivularis
}}<!--

-->[[Category:Treatment]][[Category:Crataegus (sect. Douglasia) ser. Cerrones]]