View source for Ptychostomum arcticum

{{Treatment/ID
|accepted_name=Ptychostomum arcticum
|accepted_authority=(R. Brown) J. R. Spence
|publications={{Treatment/Publication
|title=Phytologia
|place=87: 20. 2005
|year=2005
}}
|special_status={{Treatment/ID/Special_status
|code=F
|label=Selected by author to be illustrated
}}
|basionyms={{Treatment/ID/Synonym
|name=Pohlia arctica
|authority=R. Brown
}}
|synonyms={{Treatment/ID/Synonym
|name=Bryum arcticum
|authority=(R. Brown) Bruch & Schimper
}} {{Treatment/ID/Synonym
|name=B. bryoides
|authority=(R. Brown) Ångstrom
}} {{Treatment/ID/Synonym
|name=B. purpurascens
|authority=(R. Brown) Bruch & Schimper
}} {{Treatment/ID/Synonym
|name=Ptychostomum bryoides
|authority=(R. Brown) J. R. Spence
}} {{Treatment/ID/Synonym
|name=P. purpurascens
|authority=(R. Brown) J. R. Spence
}}
|hierarchy=Bryaceae;Ptychostomum;Ptychostomum subg. Ptychostomum;Ptychostomum arcticum
|hierarchy_nav=<div class="higher-taxa"><div class="higher-taxon"><small>family</small>[[Bryaceae]]</div><div class="higher-taxon"><small>genus</small>[[Ptychostomum]]</div><div class="higher-taxon"><small>subgenus</small>[[Ptychostomum subg. Ptychostomum]]</div><div class="higher-taxon"><small>species</small>[[Ptychostomum arcticum]]</div></div>
|volume=Volume 28
|mention_page=page 167, 169
|treatment_page=page 168
}}<!--

--><span class="statement" id="st-undefined" data-properties=""><b>Plants </b>in dense or open turfs, red, pink, green, or yellow-green. <b>Stems</b> 0.5–3 cm, fertile stems comose, innovations evenly foliate. <b>Leaves</b> shiny yellow-green to red or pink, crowded, strongly contorted to shrunken when dry, ovate-lanceolate, flat, 0.5–3 mm, often gradually enlarged toward stem apex; base usually green, not decurrent; margins revolute proximally, limbidium strong, in 2 or 3 rows; apex acute to acuminate; costa excurrent to long-excurrent, awn smooth or denticulate; proximal laminal cells long-rectangular, 3–5:1; medial and distal cells 15–25 µm wide, 2–3:1, walls thin to moderately thick. <b>Specialized</b> asexual reproduction absent. <b>Sexual</b> condition polyoicous, variable, often populations either synoicous or only archegoniate. <b>Seta</b> brown or red-brown, 1–3 cm, slender, straight to somewhat flexuose. <b>Capsule</b> brown, shape highly variable, elongate-pyriform to clavate, symmetric to somewhat curved, 3–5 mm, mouth orange-brown to red; hypophysis slender; operculum short-conic, weakly apiculate; peristome variable, reduced; exostome teeth yellow or brown, hyaline distally, lamellae straight, sometimes with small pores near base along mid line; endostome weakly adherent to exostome, basal membrane low to 1/2 exostome height, segments with slitlike perforations, cilia absent or rudimentary. <b>Spores</b> with size often variable in same capsule, 24–30(–32) µm, yellow.</span><!--

-->{{Treatment/Body
|phenology=Capsules mature Jul–Aug.
|habitat=Moist soil banks, wet soil
|elevation=low to high elevations (0-4500 m)
|distribution=Greenland;Alta.;B.C.;Man.;Nfld. and Labr.;Que.;Alaska;Calif.;Mont.;Nev.;Oreg.;Wash.;Wyo.;Eurasia.
|discussion=<p><i>Ptychostomum arcticum</i> is one of the most variable and confusing species in the genus. Much of this variation has been described as a series of very closely related species, including P. bryoides and <i>P. purpurascens</i>, differing in minor details of the leaves and capsule. D. T. Holyoak (2004) synonymized several of these segregates with <i>P. arcticum</i>, which is here tentatively accepted. The segregates that have been reported from the flora area are distinguished below based on the work of E. Nyholm (1986+, fasc. 3). Their distribution and ecology remain poorly understood, but <i>P. purpurascens</i> is reported from arctic North America, while P. bryoides is reported from Greenland. Capsules are needed for identification.</p><!--
--><p><i>Ptychostomum</i> purpurascens is immediately distinguished by the distal laminal cells 22–35 µm wide, capsules elongate-pyriform and symmetric, exothecial cells transversely rectangular, in 2–4 rows, and exostome teeth with small holes present along the mid line at base. <i>Ptychostomum arcticum</i> and P. bryoides contrast by distal laminal cells 17–24 µm wide; capsules clavate to ovate, symmetric or curved, exothecial cells quadrate, in 2–6 rows, and exostome teeth lacking small holes.</p>
|tables=
|references=
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-->{{#Taxon:
name=Ptychostomum arcticum
|author=
|authority=(R. Brown) J. R. Spence
|rank=species
|parent rank=subgenus
|synonyms=Bryum arcticum;B. bryoides;B. purpurascens;Ptychostomum bryoides;P. purpurascens
|basionyms=Pohlia arctica
|family=Bryaceae
|phenology=Capsules mature Jul–Aug.
|habitat=Moist soil banks, wet soil
|elevation=low to high elevations (0-4500 m)
|distribution=Greenland;Alta.;B.C.;Man.;Nfld. and Labr.;Que.;Alaska;Calif.;Mont.;Nev.;Oreg.;Wash.;Wyo.;Eurasia.
|reference=None
|publication title=Phytologia
|publication year=2005
|special status=Selected by author to be illustrated
|source xml=https://jpend@bitbucket.org/aafc-mbb/fna-data-curation.git/src/8f726806613d60c220dc4493de13607dd3150896/coarse_grained_fna_xml/V28/V28_267.xml
|genus=Ptychostomum
|subgenus=Ptychostomum subg. Ptychostomum
|species=Ptychostomum arcticum
}}<!--

-->[[Category:Treatment]][[Category:Ptychostomum subg. Ptychostomum]]