Tortula is a genus of mosses belonging to the family Pottiaceae, within the order Pottiales, class Bryopsida, and phylum Bryophyta. Like all mosses, members of Tortula are non-vascular land plants (bryophytes) that lack true roots, stems, and leaves in the vascular-plant sense, instead forming low cushions or turfs on substrates such as walls, soil, rocks, and disturbed ground.
The circumscription of Tortula has undergone considerable revision over the decades. Species formerly classified under the related genera Desmatodon, Phascum, and Pottia have been transferred into Tortula, while a number of former Tortula species have been reassigned to Hennediella, Microbryum, and Syntrichia. These rearrangements followed investigations into gametophyte characteristics, reflecting ongoing refinement of relationships within the family Pottiaceae.
Among the better-known members are Tortula muralis (Wall Screw-moss), a cosmopolitan species common on mortar, brick, and stone walls throughout Europe and beyond, and Tortula subulata (Tortula Moss), found on soil and rock in temperate regions. The genus includes species distributed across a wide range of climates and continents, with representatives recorded from the Arctic and Antarctic as well as tropical highlands.
Distribution
Tortula species occur across a broad global range, from temperate and boreal zones to polar regions including Antarctica. They colonise walls, bare soil, rock faces, and other disturbed or open substrates, with several species — notably Tortula muralis — documented as synanthropic and common in urban and agricultural environments.
Taxonomy Notes
The delimitation of Tortula within the family Pottiaceae has been historically unstable. Species previously assigned to Desmatodon, Phascum, and Pottia have been incorporated into Tortula, while other former members were transferred to Hennediella, Microbryum, and Syntrichia. These changes reflect reassessments of gametophyte morphology and character-state evolution within Pottiaceae.
