Didymodon johansenii (R.S. Williams) H.A. Crum is recorded for the first time for Italy from the Brenta Dolomites of the Southern Alps, Province of Trento. In addition, a series of unpublished records from the Austrian Alps are presented and the known distribution of the species in Central Europe is mapped. The differentiation of the species, which is well-characterized among European species by a swollen, deciduous leaf apex, is discussed. D. johansenii is a cryophilous xerophyte, usually growing in full sun on S-facing rock walls of limestone and calcareous schist in the subalpine and alpine belt of the Alps. It probably belongs to a series of bryophyte species with Central Asian origin which reached the Alps by crossing the cold steppes during the glacial maxima of the Pleistocene.