Yushania 1(2): 13. 1984.
Stems red-brown, reclining, slender, branches prostrate or sometimes arching upward; pseudoparaphyllia narrow, foliose. Stem leaves crowded, 0.7–1 mm. Branch leaves similar, slightly smaller. Specialized asexual reproduction by filiform propagula in leaf axils. Seta reddish. Capsule symmetric, 1 mm.
Phenology: Capsules mature early spring.
Habitat: Rock, epiphytic on tree trunks and bases, logs, broadleaf woodlands
Elevation: low to moderate elevations
Nfld. and Labr., N.S., Ont., Ala., Ark., Conn., Ga., Ill., Ind., Maine, Md., Mich., Mo., N.Y., N.C., Ohio, Okla., S.C., Tenn., Vt., Va., W.Va., Wis., Mexico, Central America, Asia.
Pylaisiadelpha tenuirostris is superficially similar to some specimens of Hypnum pallescens (Hypnaceae), a commonly sporophyte-bearing species with conic opercula and leaves lacking enlarged alar cells. Plants with sporophytes are rare. The rostrate opercula and conspicuous pigmented enlarged alar cells are distinctive.