Plants light or dark and vivid or clear green distally, pale buff-brown proximally with glistening white leaf bases, elongate, not rosulate. Stems thin, slender, 0.5-1(-1.5) cm, branches few to several, central strand present and conspicuous, not tomentose except in perichaetiate plants. Stem leaves fragile, closely to loosely aggregated, uniform in size, apices in sterile plants (except the youngest) usually fallen, incurved-circinate and weakly contorted when dry, erect-spreading, occasionally patent when moist, gradually long-lanceolate, 1.5-2 mm; base undifferentiated or somewhat broader than the limb, elliptical; margins of some leaves weakly undulate, constricted, lobed in scallop-shapes in several places distally, erect to incurved; apex narrowly acuminate, occasionally sharply contracted into a subula in the apical 1/3, this a papillose cylinder about the size of the costa, composed of a series of barrel-shaped segments disarticulating at constrictions, intact subula and tip of propaguloid apex with an apiculus of several cells, this usually dentate and tipped by one or two, elongate, sharply pointed clear cells, in sterile plants leaf apices caducous along zones of weakness; costa short-excurrent, in leaves of fertile plants adaxial surface covered distally by an epidermis of quadrate, papillose laminal cells, back of the costa smooth throughout—in leaves of fragile sterile plants abaxial costa surface smooth only proximally apical subula, densely papillose on both adaxial and abaxial surfaces in the distal subulate region, in cross section cells weakly differentiated and frequently rather chaotic, adaxial epidermis always present, adaxial stereid cells often disappearing in the distal region of the leaf, proximal laminal cells abruptly differentiated from distal cells, pale white-hyaline and transparent; distal laminal cells relatively large, 10-14 µm wide, lamina 1-stratose but apparently 2-stratose at juncture of lamina and costa, especially along the distal costa in propaguloid leaves of sterile plants; marginal cells undifferentiated, papillose-crenulate throughout. Specialized asexual reproduction in two modes, a general fragility of the leaf lamina as well as smaller, soft, multistratose, propaguloid deciduous leaf apices articulated by regular constrictions, falling early in units of approximately uniform length. Sexual condition apparently dioicous; perigonia not seen; perichaetiate stems tomentose, perichaetia terminal on successive perichaetial innovations; outer perichaetial leaves differentiated, especially evident when dry, longer than the cauline leaves, long-lanceolate to linear-lanceolate, fragile, tipped with long, rigid, subulate, smooth awns; rising beyond the contorted stem leaves when dry, not propaguloid, unbordered. Sporophytes unknown.
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