View source for Psilopilum

{{Treatment/ID
|accepted_name=Psilopilum
|accepted_authority=Bridel
|publications={{Treatment/Publication
|title=Bryol. Univ.
|place=2: 95. 1827 ,
}}
|basionyms=
|synonyms=
|hierarchy=Polytrichaceae;Psilopilum
|hierarchy_nav=<div class="higher-taxa"><div class="higher-taxon"><small>family</small>[[Polytrichaceae]]</div><div class="higher-taxon"><small>genus</small>[[Psilopilum]]</div></div>
|etymology=Greek psilos, naked, and pilon, hair, alluding to calyptra
|volume=Volume 27
|mention_page=page 121, 123, 124, 148
|treatment_page=page 145
}}<!--

--><span class="statement" id="st-d0_s0" data-properties="whole_organism size;whole_organism architecture;whole_organism growth form;whole_organism growth form;colony size"><b>Plants </b>small, not polytrichoid, gregarious, often in extensive colonies on soil.</span> <span class="statement" id="st-d0_s1" data-properties="stem architecture"><b>Stems </b>unbranched.</span> <span class="statement" id="st-d0_s2" data-properties="leaf architecture or shape;leaf shape;leaf shape;apex shape;apex shape"><b>Leaves </b>only slightly sheathing at base, distinctly concave to channeled, cucullate, the apex obtuse or apiculate;</span> <span class="statement" id="st-d0_s3" data-properties="lamina width;lamina architecture;margin architecture or shape;margin architecture or shape;margin shape;end orientation;marginal bud shape;border prominence">lamina broad and 1-stratose, margins entire or bluntly and irregularly toothed distally by projecting ends of rhomboidal marginal cells, forming an indistinct border;</span> <span class="statement" id="st-d0_s4" data-properties="costa architecture or pubescence or relief;apex relief or texture;adaxial lamella quantity;adaxial lamella position">costa smooth at back or roughened near apex, rarely with a few low adaxial lamellae;</span> <span class="statement" id="st-d0_s5" data-properties="lamella shape;margin shape;margin shape;margin architecture or shape;section prominence">lamellae restricted to costa, transversely undulate, margins entire or incised and irregularly dentate, marginal cells in section undifferentiated, smooth.</span> <span class="statement" id="st-d0_s6" data-properties="marginal bud architecture or pubescence or relief;marginal bud reproduction;marginal bud reproduction"><b>Sexual </b>condition dioicous;</span> <span class="statement" id="st-d0_s7" data-properties="whole_organism reproduction;whole_organism size;whole_organism growth form;perigonium prominence;perigonium shape;bract shape;bract shape">male plants smaller, perigonia conspicuous, cupulate, bracts broadly ovate, flaring at apex;</span> <span class="statement" id="st-d0_s8" data-properties="perichaetial leaf orientation;perichaetial leaf shape;perichaetial leaf length or size">perichaetial leaves erect, lanceolate, often much longer than stem-leaves.</span> <span class="statement" id="st-d0_s9" data-properties="capsule course;capsule shape;capsule architecture or shape;capsule relief;capsule shape;capsule shape"><b>Capsule </b>moderately to strongly curved and cylindric to gibbous and asymmetric, wrinkled when dry, not angled, tapering to base;</span> <span class="statement" id="st-d0_s10" data-properties="exothecium architecture or pubescence or relief;exothecial bud height or length or size;exothecial bud shape;exothecial bud quantity;exothecial bud width;wall size or width;wall arrangement;wall dehiscence or orientation;spot size or width;spot arrangement;spot dehiscence or orientation">exothecium smooth, exothecial cells short to longitudinally elongate, often with thickened radial longitudinal walls, no thin spots or pits;</span> <span class="statement" id="st-d0_s11" data-properties="stoma position">stomata superficial, at base of capsule;</span> <span class="statement" id="st-d0_s12" data-properties="operculum shape">operculum rostrate;</span> <span class="statement" id="st-d0_s13" data-properties="peristome shape;tooth quantity;tooth arrangement or course or shape;tooth arrangement;tooth shape">peristome deeply divided to below capsule rim, the teeth 32, linear, crowded, at times poorly formed and irregular in shape.</span> <span class="statement" id="st-d0_s14" data-properties="calyptra relief;calyptra relief"><b>Calyptra </b>smooth or roughened at tip.</span> <span class="statement" id="st-d0_s15" data-properties="spore size;spore relief"><b>Spores </b>large (20–25 µm), finely papillose.</span><!--

-->{{Treatment/Body
|distribution=Worldwide in arctic and subarctic areas
|discussion=<p>Species 2 (2 in the flora).</p><!--
--><p>Psilopilum is a small genus of pioneer mosses on soil in disturbed or otherwise unstable, non-calcareous sites, in arctic and subarctic North America and Eurasia. The closest affinities of Psilopilum are with Atrichum, as indicated by the tendency towards bordered leaves (P. laevigatum), finely longitudinally striate exothecium, and a similar peristome of 32 linear, crowded teeth. Sporophytes are commonly produced in both species. The best recent treatment is that of D. G. Long (1985), who examined an extensive series of collections from arctic America.</p>
|tables=
|references=
}}<!--

--><div class="treatment-key">
==Key==
<div class="treatment-key-group">
  
{| class="wikitable fna-keytable"
|-id=key-0-1
|1
|Leaves oblong-ovate, erect-appressed when dry, spreading when moist; leaf margins entire or minutely denticulate near apex; lamellae entire or crenulate in profile; capsule cylindric, weakly to moderately curved, not or weakly gibbous, suberect or inclined.
|[[Psilopilum cavifolium|Psilopilum cavifolium]]
|-id=key-0-1
|1
|Leaves ovate to oblong-obovate, erect-incurved when wet or dry; leaf margins crenate-dentate distally, hyaline (decolorate); lamellae incised, coarsely and irregularly dentate in profile; capsule ovoid-gibbous, strongly curved, horizontal.
|[[Psilopilum laevigatum|Psilopilum laevigatum]]
|}
</div></div><!--

-->{{#Taxon:
name=Psilopilum
|author=Gary L. Smith Merrill
|authority=Bridel
|rank=genus
|parent rank=family
|synonyms=
|basionyms=
|family=Polytrichaceae
|distribution=Worldwide in arctic and subarctic areas
|reference=None
|publication title=Bryol. Univ.
|publication year=
|special status=
|source xml=https://bibilujan@bitbucket.org/aafc-mbb/fna-fine-grained-xml.git/src/84153f6d59a0a91d69695978a64cee7560374f8e/V27/V27_180.xml
|genus=Psilopilum
|adaxial lamella position=low
|adaxial lamella quantity=few
|apex relief or texture=roughened
|apex shape=apiculate;obtuse
|border prominence=indistinct
|bract shape=flaring;ovate
|calyptra relief=roughened;smooth
|capsule architecture or shape=asymmetric
|capsule course=curved
|capsule relief=wrinkled
|capsule shape=tapering;not angled;cylindric;gibbous
|colony size=extensive
|costa architecture or pubescence or relief=smooth
|end orientation=projecting
|exothecial bud height or length or size=short
|exothecial bud quantity=no
|exothecial bud shape=elongate
|exothecial bud width=thin
|exothecium architecture or pubescence or relief=smooth
|lamella shape=undulate
|lamina architecture=1-stratose
|lamina width=broad
|leaf architecture or shape=sheathing
|leaf shape=cucullate;distinctly concave;channeled
|margin architecture or shape=dentate;bluntly;entire
|margin shape=incised;entire;toothed
|marginal bud architecture or pubescence or relief=smooth
|marginal bud reproduction=dioicous;sexual
|marginal bud shape=rhomboidal
|operculum shape=rostrate
|perichaetial leaf length or size=often much longer
|perichaetial leaf orientation=erect
|perichaetial leaf shape=lanceolate
|perigonium prominence=conspicuous
|perigonium shape=cupulate
|peristome shape=divided
|section prominence=undifferentiated
|spore relief=papillose
|spore size=large
|spot arrangement=radial
|spot dehiscence or orientation=longitudinal
|spot size or width=thickened
|stem architecture=unbranched
|stoma position=superficial
|tooth arrangement=crowded
|tooth arrangement or course or shape=linear
|tooth quantity=32
|tooth shape=irregular
|wall arrangement=radial
|wall dehiscence or orientation=longitudinal
|wall size or width=thickened
|whole_organism architecture=not polytrichoid
|whole_organism growth form=plant;plant;gregarious
|whole_organism reproduction=male
|whole_organism size=smaller;small
}}<!--

-->[[Category:Treatment]][[Category:Polytrichaceae]]