Grimmia subg. Gasterogrimmia Schimper, Coroll. 46. 1856.
Authors: Roxanne I. Hastings & Dr. Henk C. Greven
Plants to 15 mm. Stem central strand strong. Stem leaves oblong-ovate to oblong-lanceolate, keeled or concave, margins plane, costa prominent, distal lamina 2-stratose (1-stratose for G. plagiopodia). Seta arcuate to sigmoid (except G. americana), eccentrically attached to capsule. Capsule immersed, smooth, ventricose; stomates 3--4, large, at base of capsule; calyptra mitrate, just covering operculum.
Species 4 (4 in the flora): North America, Mexico, Central America, South America, Eurasia, n. Africa, Pacific Islands (New Zealand), Australasia, Antarctic.
Members of this subgenus are recognized by their commonly occurring immersed, ventricose capsules on arcuate to sigmoid setae that are eccentrically attached. Additionally, all these species have three to four large stomates at the very base of the capsule. Most members of the subgenus are restricted to calcareous habitats. Jaffueliobryum is the only other group in the Grimmiaceae to be so strongly tied to calcareous substrates.
