Ptychostomum Hornsch.
  • Syll. Pl. Nov. 1(3): 62–64. 1824[1822].

Cite taxon page as 'WFO (2020): Ptychostomum Hornsch. Published on the Internet; Accessed on: 29 Oct 2020'

General Information

Plants small to very large, in dense or open turfs, red, pink, yellow-green, or brown-green. Stems0.5-4(-12) cm, tufted, comose or evenly foliate, freely branching by subfloral innovations; rhizoids few to many, micronemata and macronemata present. Leaves weakly to strongly contorted or shrunken when dry, erect to erect-spreading when moist, ovate, ovate-lanceolate, or orbicular, flat to concave, (0.5-)1-4(-5) mm; base decurrent or not; margins plane or revolute, entire to denticulate distally, 1- or 2-stratose, limbidium usually present; apex obtuse to acuminate; costa usually percurrent to long-excurrent, awn smooth or denticulate, guide cells usually present in 1 layer; alar cells not differentiated; laminal areolation heterogeneous; proximal laminal cells gradually short- to long-rectangular, , 2-4:1; medial and distal cells rhomboidal to hexagonal, usually 2-4:1, walls thin to very incrassate, porose or not. Specialized asexual reproduction rare, by filiform gemmae in stem leaf axils and on rhizoids. Sexual condition dioicous, synoicous, autoicous, or polyoicous; perigonia and perichaetia terminal; perigonial and perichaetial leaves somewhat differentiated, outer leaves somewhat enlarged and more acuminate, inner leaves smaller, narrowly ovate-lanceolate to triangular. Seta single, straight to flexuose. Capsule highly variable, suberect, inclined, or nutant, ovate, obovate, pyriform, clavate, or turbinate, 2-6(-7) mm; hypophysis slender or thick; operculum conic to low-convex, rounded to apiculate; peristome double; exostome yellow, orange, or brown basally, usually hyaline distally, teeth well developed, lanceolate; endostome sometimes adherent to exostome at base, basal membrane high, segments usually well developed, narrowly to broadly perforated, cilia variously short and appendiculate, or absent. Spores shed singly, size often variable in same collection and capsule, 10-50 µm, smooth to distinctly papillose, yellow, brown, black, or green.

  • Provided by: [B].Flora of North America @
    • Source: [
    • 1
    • ]. 

    Included Species

     Information From

    World Flora Online Data. 2017.
    • A CC0 1.0 Universal (CC0 1.0).
    Flora of North America @
    'Flora of North America @ eFloras (2008). Published on the Internet [accessed August 2016]' Missouri Botanical Garden, St. Louis, MO & Harvard University Herbaria, Cambridge, MA.
    • B Flora of North America Association
    World Flora Online consortium
    World Flora Online Data. 2018.
    • C CC0 1.0 Universal (CC0 1.0).