Plants: in loose low open turfs, green or rarely pinkish red. Stems: 2â4(â6) cm, fertile stems comose, innovations evenly foliate. Leaves: green, yellow-green, or rarely red or pink, distant, strongly contorted to shrunken when dry, ovate-lanceolate, flat, 1â3 mm, not much enlarged toward stem apex; base usually green, strongly and broadly decurrent, decurrencies almost reaching next more proximal leaf; margins revolute proximally, plane distally, limbidium weak, in 1 (or 2) rows; apex acute; costa not reaching apex to short-excurrent, awn slender; proximal laminal cells hexagonal to rectangular, 3â4:1; medial and distal cells 18â25(â30) µm wide, 2â3:1, walls thin. Specialized: asexual reproduction absent. Sexual: condition dioicous. Seta: red-brown, 2â4 cm, slender, straight to somewhat flexuose. Capsule: brown, turbinate to pyriform, symmetric, 3â4 mm, mouth yellow; operculum convex, apiculate; peristome well developed; exostome teeth yellow basally, hyaline distally, lamellae straight, pores absent near base along mid line; endostome not adherent to exostome, basal membrane 1/2 exostome height, segments broadly perforate, cilia well developed, long, appendiculate. Spores: (12â)14â18 µm, yellow or green. Phenology: Capsules mature JunâAug. Habitat: Wet soil, wetlands, along streams Elevation: low to high elevations (0-3500 m) Distribution: Greenland, Alta., B.C., Man., Nfld. and Labr., N.W.T., N.S., Nunavut, Ont., P.E.I., Que., Sask., Yukon, Alaska, Ariz., Calif., Colo., Conn., Idaho, Maine, Mass., Mich., Minn., Mont., Nev., N.H., N.Dak., Ohio, Oreg., Pa., Utah, Vt., Va., Wash., W.Va., Wis., Wyo., South America, Eurasia, Africa, Pacific Islands (New Zealand), Australia.
Discussion: Ptychostomum weigelii is a common arctic-boreal to north-temperate species in wet sites, easily identified by the broad, long marginal decurrencies of the leaves that nearly reach to the next leaf. Leaves of the similar P. cyclophyllum and P. turbinatum are either not decurrent or only produce short, very slender decurrencies. Plants of P. weigelii from Colorado are pinkish red.