Weissia wilsonii replaces W. multicapsularis, which in 2019 turned out to be erroneously based on a mixed collection of W. longifolia and Tortula acaulon.
W. wilsonii is a pioneering species that grows as scattered stems or in loose cushions similar to W. longifolia. Both species have long, relatively broad perichaetial leaves which often partially obscure the cleistocarpous capsules. The most important diagnostic character of W. wilsonii is the large operculum (lid), although there is a small amount of overlap with W. longifolia. Care must be taken to measure the length of the operculum rather than the calyptra, if present, as it is much larger. Shoots can have more than one capsule and then W. wilsonii may resemble W. sterilis, often a larger plant with longer stem leaves.