AbstractA new genus and family are proposed for a unique moss which is so greatly reduced that it is difficult to assess its affinities.Viridivellus pulchellum(Viridivelleraceae) which has the appearance of a tiny green fleece was found on earth banks in tropical forests in Queensland, Australia. Vegetative leaves are absent, their function taken over by the photosynthetic branching system of the protonema as inEphemeropsis, which is not considered to be closely related. The tiny bud-like, synoecious inflorescence has a few short, nerved bracts; there is a short seta with a central strand and a cleistocarpic capsule with a long rostrum and cucullate calyptra.