Funariaceae Schwaegr. in Willd., Sp. Pl. ed. 4, 5(2): 43. 1830, "Funariae."
Physcomitriaceae Schimp., Syn. Musc. Eur. 312. 1860, nom. illeg., "Physcomitrieae."
Physcomitrellaceae Schimp., Syn. Musc. Eur. ed. 2, LXXXIV, 7. 1876, "Physcomitrelleae."
Plants pale‑ to bright‑ to yellow‑green, minute to medium‑sized, usually gregarious in tufts on soil. Stems erect, simple or often branching sympodially by subperigonial innovations, usually more or less naked below (except for rhizoids), leaves more or less equally spaced or clustered toward stem apices, hyalodermis and central strand present; axillary hairs with 1 to few colored basal cells and a single elongate hyaline apical cell. Leaves typically erect‑spreading and often contorted when dry, sometimes more or less erect, when moist imbricate to wide‑spreading, typically oblong‑ovate to obovate, sometimes elliptic, lanceolate or subulate, concave or concave‑keeled, rarely flat; apices obtuse, acute or acuminate; margins entire to serrate above, rarely ciliate, entire below, plane to narrowly incurved above, plane below; costa ending near midleaf to excurrent, with a single (dorsal) stereid band, rarely with two small stereid bands (Cygnicollum); upper cells typically subquadrate or short‑rectangular, sometimes oblong‑hexagonal, thin‑ to firm‑walled, smooth, sometimes becoming longer and narrower at the margins and forming a border, toward the insertion usually becoming long‑rectangular, alar cells not or weakly differentiated. Asexual propagula often none, sometimes with rhizoidal tubers. Autoicous, less often paroicous, rarely synoicous or polygamous. Perigonial stems shorter than perichaetial stems, bracts sometimes differentiated; paraphyses numerous, with swollen terminal cells. Perichaetial leaves usually not differentiated from upper vegetative leaves; paraphyses absent. Setae very short to elongate, straight to cygneous, rarely geniculate, often twisted, not to strongly hygroscopic, smooth or rarely roughened. Capsules immersed to long‑exserted, cleistocarpous or more often stegocarpous, subglobose to pyriform to ovoid to cylindric, erect to inclined to pendent, straight to curved, strongly asymmetric to symmetric, weakly to strongly sulcate when dry, at least in the neck; the mouth from 1/4 to equal the diameter of the capsule, straight or oblique, parallel or perpendicular to the longitudinal axis of the urn; the neck usually well differentiated, from less than 1/4 to more than 1/2 the length of the capsule; exothecial cells more or less isodiametric to elongate, usually becoming oblate at the mouth; stomata restricted to the neck, of a single guard cell with a central elongate pore, immersed or superficial; columella present but in spore sac often resorbed at maturity; annuli present or absent; opercula, when differentiated, plano‑convex to conic to rostrate; peristome diplolepidous, double, single and exostomial or rarely endostomial, or absent, teeth attached at or inserted below mouth, erect to sigmoid, sometimes with apices of teeth coalescing with a lattice disk, papillose‑striolate to striate on the front surface, endostome segments opposite the exostome teeth, often fused at base into a basal membrane, segments from 1/4 to almost as long as the teeth, free or adherent to the teeth, often ornamented on the inner surface, cilia none. Spores spherical to reniform, finely roughened and almost smooth to distinctly roughened. Calyptrae mitrate or cucullate, typically lobed at base, usually rostrate, often inflated at base, naked, usually smooth, sometimes papillose, rarely angled or pleated.