Plants: in dense or open turfs, dull green, yellow-green, or brownish. Stems: (1â)2â4(â6) cm, fertile stems comose, innovations evenly foliate. Leaves: dull green to yellow-green, crowded, strongly contorted to shrunken when dry, often broadly ovate-lanceolate, somewhat concave, 1â3 mm, gradually enlarged toward stem apex; base green, not or weakly decurrent; margins plane or occasionally weakly revolute proximally, limbidium strong, in 2 or 3 rows; apex acute to acuminate; costa percurrent to short-excurrent, awn slender; proximal laminal cells rectangular, 3â4:1; medial and distal cells 18â25(â30) µm wide, 2â3:1, walls thin. Specialized: asexual reproduction absent. Sexual: condition dioicous. Seta: brown or red-brown, 1â3(â4) cm, slender, straight to somewhat flexuose. Capsule: pale yellow to yellow-brown, becoming black with age, turbinate to short-pyriform, symmetric, 3â5 mm, mouth yellow; operculum conic, apiculate; peristome well developed; exostome teeth yellow to orange basally, hyaline distally, lamellae straight, pores absent near base along mid line; endostome not adherent to exostome, basal membrane 1/2 exostome height, segments with ovate perforations, cilia appendiculate to nodose. Spores: 18â22 µm, yellow to brown. Phenology: Capsules mature JunâAug. Habitat: Wet soil in calcareous wetlands Elevation: low to high elevations (0-3500 m) Distribution: Greenland, Alta., B.C., Nfld. and Labr., N.W.T., Yukon, Alaska, Calif., Colo., Idaho, Mont., Nev., Oreg., Utah, Wash., Wyo., South America (Argentina, Chile, Ecuador, Peru), Eurasia (including Turkey), Africa.
Discussion: Ptychostomum turbinatum is a circumpolar arctic-boreal to temperate species. The dull green to yellow-green shoots, strongly shrunken ovate-lanceolate leaves, and turbinate capsule are diagnostic. Old capsules often turn black and become strongly constricted just below the mouth. The stems are sparsely radiculose, sometimes with clusters of rhizoids arising from the proximal leaf axils. Ptychostomum schleicheri is much larger, pale yellow distally, with wider leaves and much wider distal laminal cells. Large specimens, 8â12 cm, with long narrow ovate-lanceolate leaves and elongate-pyriform capsules, represent an undescribed species.