View source for Acaulon ← Acaulon You do not have permission to edit this page, for the following reason: The action you have requested is limited to users in the group: Users. You can view and copy the source of this page. {{Treatment/ID |accepted_name=Acaulon |accepted_authority=Müller Hal. |publications={{Treatment/Publication |title=Bot. Zeitung (Berlin) |place=5: 99. 1847 , }} |basionyms= |synonyms= |hierarchy=Pottiaceae;Pottiaceae subfam. Pottioideae;Acaulon |hierarchy_nav=<div class="higher-taxa"><div class="higher-taxon"><small>family</small>[[Pottiaceae]]</div><div class="higher-taxon"><small>subfamily</small>[[Pottiaceae subfam. Pottioideae]]</div><div class="higher-taxon"><small>genus</small>[[Acaulon]]</div></div> |etymology=Greek a-, without, and kaulos, stalk or stem, alluding to stemless habit |volume=Volume 27 |mention_page=page 480, 604, 638 |treatment_page=page 637 }}<!-- --><span class="statement" id="st-d0_s0" data-properties="whole_organism architecture or shape;whole_organism growth form;whole_organism arrangement;whole_organism coloration;whole_organism coloration;whole_organism growth form"><b>Plants </b>bulbiform, gregarious or scattered, reddish to yellowish-brown distally, brown proximally.</span> <span class="statement" id="st-d0_s1" data-properties="stem height or length or size;stem some measurement"><b>Stems </b>short, to 0.5 mm;</span> <span class="statement" id="st-d0_s2" data-properties="hyalodermi presence;scleroderm presence;central strand presence">hyalodermis absent, sclerodermis absent, central strand absent;</span> <span class="statement" id="st-d0_s3" data-properties="axillary hair quantity;proximal cell-wall size or width">axillary hairs to ca. 5 cells in length, proximal cell-walls sometimes thickened.</span> <span class="statement" id="st-d0_s4" data-properties="stem-leaf fixation or orientation"><b>Stem-</b>leaves strongly appressed and apices usually reflexed when dry, appressed to weakly spreading when moist;</span> <span class="statement" id="st-d0_s5" data-properties="apex orientation;apex orientation;apex shape;adaxial surface shape;adaxial surface some measurement">ovate, adaxial surface deeply concave, 0.5–1.75 mm;</span> <span class="statement" id="st-d0_s6" data-properties="base shape;proximal margin variability">base not differentiated in shape, proximal margins not differentiated;</span> <span class="statement" id="st-d0_s7" data-properties="distal margin shape;distal margin orientation;distal margin architecture or shape;distal margin architecture or shape">distal margins plane or very weakly recurved, entire to serrulate or dentate;</span> <span class="statement" id="st-d0_s8" data-properties="apex shape;apex architecture or shape">apex broadly acute, abruptly apiculate;</span> <span class="statement" id="st-d0_s9" data-properties="costa architecture;apiculu fragility or size;apiculu shape;awn height or length or size;awn architecture or shape;adaxial outgrowth presence;adaxial cell shape;row quantity">costa excurrent in a stout, sharp apiculus, occasionally as a short, occasionally dentate awn, adaxial outgrowths absent in American species, adaxial cells elongate, in 3–4 rows;</span> <span class="statement" id="st-d0_s10" data-properties="transverse-section shape;adaxial epidermis presence;band presence;guide cell quantity;layer quantity;hydroid strand presence;epidermis position;band presence;band fragility;band shape;abaxial epidermis presence">transverse-section round, adaxial epidermis present, adaxial stereid band absent, guide cells 0–4 in 1 layer, hydroid strand usually present, occasionally central, abaxial stereid band present, usually weak, rounded in sectional shape, abaxial epidermis present;</span> <span class="statement" id="st-d0_s11" data-properties="proximal cell shape;proximal cell shape;proximal cell width;proximal cell quantity;proximal cell quantity;wall width">proximal cells not differentiated in shape, rectangular, little wider than distal cells, 3–4: 1, walls of proximal cells thin;</span> <span class="statement" id="st-d0_s12" data-properties="distal medial cell shape;distal medial cell width;distal medial cell quantity;distal medial cell quantity;distal medial cell architecture">distal medial cells roundedquadrate to rhomboid, ca. 13–15 µm wide, 1–4: 1, 1-stratose;</span> <span class="statement" id="st-d0_s13" data-properties="distal medial cell shape;distal medial cell width;distal medial cell quantity;papilla presence;papilla size;papilla architecture">papillae absent or occasionally large and simple, one per lumen, cell-walls evenly thickened, occasionally highly thickened on abaxial walls, convex on both sides of lamina.</span> <span class="statement" id="st-d0_s14" data-properties=""><b>Specialized </b>asexual reproduction absent.</span> <span class="statement" id="st-d0_s15" data-properties="cell-wall size or width;cell-wall size or width;cell-wall shape;cell-wall development;cell-wall reproduction;cell-wall presence;cell-wall reproduction;whole_organism reproduction;whole_organism architecture;whole_organism size;whole_organism reproduction;whole_organism reproduction;whole_organism growth form"><b>Sexual </b>condition dioicous and perigoniate plants smaller, or monoicous, usually paroicous.</span> <span class="statement" id="st-d0_s16" data-properties="perichaetium position or structure subtype;interior leaf size"><b>Perichaetia </b>terminal, interior leaves somewhat enlarged.</span> <span class="statement" id="st-d0_s17" data-properties="seta height or length or size;seta some measurement"><b>Seta </b>very short, to 0.2 mm.</span> <span class="statement" id="st-d0_s18" data-properties="capsule dehiscence;capsule shape;apiculu quantity;apiculu some measurement;annulus presence"><b>Capsule </b>cleistocarpous, spheric, apiculus lacking, ca. 0.4–0.7 mm, annulus absent.</span> <span class="statement" id="st-d0_s19" data-properties="calyptra shape;calyptra shape"><b>Calyptra </b>mitrate, often lobed.</span> <span class="statement" id="st-d0_s20" data-properties="spore atypical some measurement;spore some measurement;spore coloration;spore coloration"><b>Spores </b>ca. 25–35 (–50) µm. KOH laminal color reaction red.</span><!-- -->{{Treatment/Body |distribution=Nearly worldwide;mainly in temperate regions |discussion=<p>Species 15 (3 in the flora).</p><!-- --><p>Acaulon is similar to species of Microbryum in the bulbiform habit, leaves red in KOH, but its species are even smaller in size, and the capsules are spheric, lacking an apiculus. Papillae are absent in two of the three species. Although spore size and ornamentation have figured in taxonomy in the past, according to H. A. Crum and L. E. Anderson (1981) there is much overlap; but, similarly, their use of differences in margin recurvature and seta length do not hold. Taxa belonging to the old, superficially similar Phascum have been recently placed largely with Tortula and Microbryum (R. H. Zander 1993). I. G. Stone (e.g., 1989) has studied the genus extensively in Australia, and Casas de Puig (e.g., C. Casas de Puig et al. 1990) and her students have done the same for the Iberian Peninsula.</p> |tables= |references={{Treatment/Reference |id=bryan1956b |text=Bryan, V. S. 1956b. Cytological and taxonomic studies of some species of Astomum, Acaulon and Phascum. Bryologist 59: 118–129. }}{{Treatment/Reference |id=grout1922a |text=Grout, A. J. 1922–1940. Acaulon. In: A. J. Grout, Moss Flora of North America, North of Mexico. 3 vols. in 12 parts. Newfane, Vt. and New York. Vol. 1, pp. 194–195. }} }}<!-- --><div class="treatment-key"> ==Key== <div class="treatment-key-group"> {| class="wikitable fna-keytable" |-id=key-0-1 |1 |Leaves awned, laminal cells papillose abaxially. |[[Acaulon schimperianum|Acaulon schimperianum]] |-id=key-0-1 |1 |Leaves cuspidate or muticus, laminal cells smooth |[[#key-0-2| > 2]] |-id=key-0-2 |2 |Plants often three-angled, about 1 mm, leaves keeled, seta about as long as the diameter of the capsule, spores about 30 µm, finely papillose. |[[Acaulon triquetrum|Acaulon triquetrum]] |-id=key-0-2 |2 |Plants flattened-globose or three-angled, about 2 mm, leaves broadly channeled, seta short, about 0.3 the diameter of the capsule, spores 30-50 µm, smooth or papillose. |[[Acaulon muticum|Acaulon muticum]] |} </div></div><!-- -->{{#Taxon: name=Acaulon |author=Richard H. Zander |authority=Müller Hal. |rank=genus |parent rank=subfamily |synonyms= |basionyms= |family=Pottiaceae |distribution=Nearly worldwide;mainly in temperate regions |reference=bryan1956b;grout1922a |publication title=Bot. Zeitung (Berlin) |publication year= |special status= |source xml=https://bibilujan@bitbucket.org/aafc-mbb/fna-fine-grained-xml.git/src/84153f6d59a0a91d69695978a64cee7560374f8e/V27/V27_939.xml |subfamily=Pottiaceae subfam. Pottioideae |genus=Acaulon |abaxial epidermis presence=absent |adaxial cell shape=elongate |adaxial epidermis presence=absent |adaxial outgrowth presence=absent |adaxial surface shape=concave |adaxial surface some measurement=0.5mm;1.75mm |annulus presence=absent |apex architecture or shape=apiculate |apex orientation=appressed;weakly spreading |apex shape=acute;ovate |apiculu fragility or size=stout |apiculu quantity=lacking |apiculu shape=sharp |apiculu some measurement=0.4mm;0.7mm |awn architecture or shape=dentate |awn height or length or size=short |axillary hair quantity=0;5 |band fragility=weak |band presence=absent;absent |band shape=rounded |base shape=not differentiated |calyptra shape=lobed;mitrate |capsule dehiscence=cleistocarpous |capsule shape=spheric |cell-wall development=specialized |cell-wall presence=absent |cell-wall reproduction=sexual;asexual |cell-wall shape=convex |cell-wall size or width=thickened;thickened |central strand presence=absent |costa architecture=excurrent |distal margin architecture or shape=dentate;entire;serrulate |distal margin orientation=recurved |distal margin shape=plane |distal medial cell architecture=1-stratose |distal medial cell quantity=1;4 |distal medial cell shape=roundedquadrate;rhomboid |distal medial cell width=13um;15um |epidermis position=central |guide cell quantity=0;4 |hyalodermi presence=absent |hydroid strand presence=absent |interior leaf size=enlarged |layer quantity=1 |papilla architecture=simple |papilla presence=absent |papilla size=large |perichaetium position or structure subtype=terminal |proximal cell quantity=1;3;4 |proximal cell shape=rectangular;not differentiated |proximal cell width=wider |proximal cell-wall size or width=thickened |proximal margin variability=not differentiated |row quantity=3;4 |scleroderm presence=absent |seta height or length or size=short |seta some measurement=0mm;0.2mm |spore atypical some measurement=35um;50um |spore coloration=red;laminal |spore some measurement=25um;35um |stem height or length or size=short |stem some measurement=0mm;0.5mm |stem-leaf fixation or orientation=appressed |transverse-section shape=round |wall width=thin |whole_organism architecture=perigoniate |whole_organism architecture or shape=bulbiform |whole_organism arrangement=scattered |whole_organism coloration=brown;reddish;yellowish-brown distally |whole_organism growth form=plant;plant;gregarious |whole_organism reproduction=paroicous;monoicous;dioicous |whole_organism size=smaller }}<!-- -->[[Category:Treatment]][[Category:Pottiaceae subfam. 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