A new species, Taxiphyllum townsendii Ochyra & Ireland (Hypnaceae, Musci), is described from Sri Lanka. The species was earlier known under the name Plagiothecium ceylonense Brotherus ex Dixon, but this name was not validly published and therefore a new name is needed. Taxiphyllum townsendii is similar in many ways to the common eastern North American species, T. deplanatum (Bruch & Schimper ex Sullivant) M. Fleischer, but differs by its larger, often oblong-lanceolate leaves that are abruptly or gradually short- or long-acuminate; much longer and narrower mid-leaf cells; short-rectangular, very broad basal leaf cells that form a distinct 1- to 2-seriate strip at the leaf insertion; and a prominent angular group of large quadrate to short-rectangular cells that extend up the margins by four to 10 cells. Taxiphyllum subretusum (Thwaites & Mitten) O'Shea is transferred to the genus Phyllodon Schimper as P. subretusus (Thwaites & Mitten) Ochyra & Ireland and the name is lectotypified. The validity of the name Entodon isopterygioides (Dixon) Dixon is discussed and this name is considered to be validly published.