# Ptychostomum

Ptychostomum is a genus of mosses belonging to the family Bryaceae. It has an almost cosmopolitan distribution. It has two subgenera, Psychostomum (Ptychostomum) and Psychostomum (Cladodium).

## Species

The following species are recognised in the genus Ptychostomum:
* Ptychostomum acutiforme (Limpr.) J.R. Spence
* Ptychostomum altisetum (Müll.Hal.) J.R.Spence & H.P.Ramsay
* Ptychostomum amblyodon (Müll. Hal.) Chen Y. Wang & J.C. Zhao
* Ptychostomum angustifolium (Brid.) J.R.Spence & H.P.Ramsay
* Ptychostomum archangelicum (Bruch & Schimp.) J.R. Spence
* Ptychostomum arcticum (R. Br.) J.R. Spence
* Ptychostomum austriacum (Köckinger, Holyoak & Suanjak) D. Bell & Holyoak
* Ptychostomum badium (Bruch ex Brid.) J.R.Spence
* Ptychostomum bimum (Schreb.) J.R. Spence
* Ptychostomum bornholmense (Wink. & R. Ruthe) Holyoak & N. Pedersen
* Ptychostomum bryoides (R.Br.) J.R.Spence
* Ptychostomum calophyllum (R. Br.) J.R. Spence
* Ptychostomum cellulare (Hook.) D. Bell & Holyoak
* Ptychostomum cernuum (Hedw.) Hornsch.
* Ptychostomum chorizodontum (Cardot & Broth.) J.R. Spence
* Ptychostomum compactum Hornsch.
* Ptychostomum creberrimum (Taylor) J.R. Spence & H.P. Ramsay
* Ptychostomum cryophilum (Mårtensson) J.R. Spence
* Ptychostomum cyclophyllum (Schwägr.) J.R. Spence
* Ptychostomum cylindrothecium (R. Br. bis) J.R. Spence & H.P. Ramsay
* Ptychostomum dicarpum (E.B. Bartram) J.R. Spence
* Ptychostomum donianum (Grev.) Holyoak & N. Pedersen
* Ptychostomum elegans (Nees ex Brid.) D. Bell & Holyoak
* Ptychostomum funkii (Schwägr.) J.R. Spence
* Ptychostomum hawaiicum (Hoe) J.R. Spence
* Ptychostomum imbricatulum (Müll. Hal.) Holyoak & N. Pedersen
* Ptychostomum inclinatum (Sw. ex Brid.) J.R.Spence
* Ptychostomum intermedium (Brid.) J.R. Spence
* Ptychostomum knowltonii (Barnes) J.R. Spence
* Ptychostomum lamprochaete (Dusén) J.R. Spence
* Ptychostomum lonchocaulon (Müll. Hal.) J.R. Spence
* Ptychostomum longisetum (Blandow ex Schwägr.) J.R. Spence
* Ptychostomum marratii (Hook. & Wilson) J. R. Spence
* Ptychostomum meesioides (Kindb.) J.R. Spence
* Ptychostomum minii (Podp. ex Guim.) D.Bell & Holyoak
* Ptychostomum moravicum (Podp.) Ros & Mazimpaka
* Ptychostomum neodamense (Itzigs.) J.R. Spence
* Ptychostomum nitidulum (Lindb.) J.R. Spence
* Ptychostomum ovatum (Hedw.) J.R.Spence
* Ptychostomum pacificum J.R. Spence & Shevock
* Ptychostomum pallens (Sw.) J.R. Spence
* Ptychostomum pallescens (Schleich. ex Schwägr.) J.R. Spence
* Ptychostomum pauperculum (E.B. Bartram) J.R. Spence
* Ptychostomum pendulum Hornsch.
* Ptychostomum pseudotriquetrum (Hedw.) J.R. Spence & H.P. Ramsay ex Holyoak & N. Pedersen
* Ptychostomum reedii (H. Rob.) J.R. Spence
* Ptychostomum rubens (Mitt.) Holyoak & N. Pedersen
* Ptychostomum rutilans (Brid.) J.R. Spence
* Ptychostomum salinum (I. Hagen ex Limpr.) J.R. Spence
* Ptychostomum schleicheri (DC.) J.R. Spence
* Ptychostomum sibiricum (Lindb. & Arnell) J.R. Spence
* Ptychostomum subneodamense (Kindb.) J.R. Spence
* Ptychostomum torquescens (Bruch & Schimp.) Ros & Mazimpaka
* Ptychostomum touwii Bijlsma, Kruijer & M. Stech
* Ptychostomum turbinatum (Hedw.) J.R. Spence
* Ptychostomum vermigerum (Arnell & C.E.O. Jensen) J.R. Spence
* Ptychostomum vernicosum (Dusén) J.R. Spence
* Ptychostomum warneum (Schwägr. ex Steud.) J.R. Spence
* Ptychostomum weigelii (Biehler) J.R.Spence
* Ptychostomum wrightii (Sull. & Lesq.) J.R. Spence