Abstract
A new propaguloid species of Pottiaceae (Musci) Didymodon hedysariformis is described from the Tuva region (South Siberia Mountains, Russia). Among the propaguloid species of Pottiaceae it differs in its gradually narrowing leaves with rounded or blunt tips; apex variably and repeatedly deeply notched and windingly-fractured, including lamina as well costa, not swollen or terete, when matured deciduous as propagulum.