View source for Taraxacum laurentianum

{{Treatment/ID
|accepted_name=Taraxacum laurentianum
|accepted_authority=Fernald
|publications={{Treatment/Publication
|title=Rhodora
|place=35: 375, plate 272, figs. 5–9. 1933
|year=1933
}}
|common_names=Gulf of St. Lawrence dandelion;pissenlit du golfe du Saint-Laurent
|basionyms=
|synonyms=
|hierarchy=Asteraceae;Asteraceae tribe Cichorieae;Taraxacum;Taraxacum laurentianum
|hierarchy_nav=<div class="higher-taxa"><div class="higher-taxon"><small>family</small>[[Asteraceae]]</div><div class="higher-taxon"><small>tribe</small>[[Asteraceae tribe Cichorieae]]</div><div class="higher-taxon"><small>genus</small>[[Taraxacum]]</div><div class="higher-taxon"><small>species</small>[[Taraxacum laurentianum]]</div></div>
|volume=Volume 19
|mention_page=page 242
|treatment_page=page 248
}}<!--

--><span class="statement" id="st-undefined" data-properties=""><b>Plants </b>10–42 cm; taproots branched. <b>Stems</b> 1–5+, erect to ascending, purplish, (usually exceeding leaves), glabrate to sparsely villous, sometimes more densely so distally. <b>Leaves</b> 5–10+; usually erect, sometimes patent; sessile to ± broadly winged-petiolate; blades oblanceolate (some younger leaves ± runcinate at least proximally), 10–30 × 2–4 cm, bases cuneate to attenuate, margins sometimes ± deeply lobed (younger leaves), usually toothed, larger teeth well developed, lobelike, retrorse to antrorse, lanceolate to triangular or sometimes deltate, sometimes double, acuminate, apices obtuse, faces adaxially sparsely pilose or glabrate (denser on midveins), abaxially glabrous or glabrate. <b>Calyculi</b> 15–18, ascending, later spreading and recurving, greenish or purplish, broadly lanceolate to narrowly ovate (herbaceous) bractlets in 2–3 series, 15–21 × 3.5–5.5 mm, margins hyaline, often purplish, narrowly scarious, apices long- to short-acuminate, strongly horned, tips purplish, scarious, erose. <b>Involucres</b> green, broadly campanulate, 18–26 mm. <b>Phyllaries</b> 18–25 in 2 series, lanceolate (outer) to ovate-lanceolate (inner), 2.5–5.2 mm wide, margins scarious narrowly or not (outer) to broadly so proximally and narrowly distally (inner), apices long-acuminate (sometimes tapered), strongly horned, tips scarious, purplish black, erose. <b>Florets</b> ca. 150+; corollas yellow (abaxially gray-striped, becoming purplish in drying), 14–25 × 0.8–1.5+ mm. <b>Cypselae</b> grayish-olivaceous to tan or olivaceous straw, bodies oblanceoloid to obovoid, 3.2–4 mm, cones narrowly conic, 0.9–1.2 mm, beaks slender, 10–17 mm, ribs 5 (wide)–14 (narrow), faces proximally ± tuberculate (sometimes ribs smooth), muricate in distal 1/3–1/2; pappi creamy, 8–9.5 mm. <b>2n</b> = 40 [unpublished].</span><!--

-->{{Treatment/Body
|phenology=Flowering summer.
|habitat=Calcareous, seashore meadows and gravelly seashores (coastal), turfy areas of seaside taluses, sandy riverside meadows in boreal forest zone
|elevation=0–5 m
|distribution=Nfld. and Labr. (Nfld.);Que.
|discussion=<p>Of conservation concern.</p><!--
--><p>Though very similar to Taraxacum ceratophorum, this Gulf of St. Lawrence endemic stands out by its statistically significantly larger heads and other parts (L. Brouillet, unpubl. data). It also occupies a habitat atypical of normal T. ceratophorum in the area. It is possible that the species is under threat from its introduced congener T. officinale, and from human activities in its fragile, easily disturbed coastal habitat.</p>
|tables=
|references=
}}<!--

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-->{{#Taxon:
name=Taraxacum laurentianum
|author=
|authority=Fernald
|rank=species
|parent rank=genus
|synonyms=
|basionyms=
|family=Asteraceae
|phenology=Flowering summer.
|habitat=Calcareous, seashore meadows and gravelly seashores (coastal), turfy areas of seaside taluses, sandy riverside meadows in boreal forest zone
|elevation=0–5 m
|distribution=Nfld. and Labr. (Nfld.);Que.
|reference=None
|publication title=Rhodora
|publication year=1933
|special status=
|source xml=https://jpend@bitbucket.org/aafc-mbb/fna-data-curation.git/src/9216fc802291cd3df363fd52122300479582ede7/coarse_grained_fna_xml/V19-20-21/V19_324.xml
|tribe=Asteraceae tribe Cichorieae
|genus=Taraxacum
|species=Taraxacum laurentianum
}}<!--

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