Rhytidiadelphus is a genus of pleurocarpous mosses in the family Hylocomiaceae, order Hypnales (class Bryopsida, phylum Bryophyta). The genus was first described by the German botanist Karl Gustav Limpricht in 1906. Species are medium to large, freely branched mosses that typically form loose, spreading mats or wefts on the ground in moist, shaded habitats such as woodlands, heathlands, and grassy areas.
The most widespread and recognisable member is Rhytidiadelphus squarrosus, commonly known as springy turf-moss or square goose-neck moss, which is abundant in lawns, meadows, and grassy banks across temperate regions of the Northern Hemisphere. R. triquetrus (big shaggy moss) is a robust species of woodland floors, and R. loreus (little shaggy moss) is characteristic of oceanic upland heaths. The genus has a cosmopolitan distribution, with species recorded across Europe, North America, Asia, and New Zealand.
Etymology
The name Rhytidiadelphus derives from the Greek rhytis (wrinkle) and adelphos (brother), alluding to the genus's close relationship to Rhytidium, another moss genus, with the suffix indicating a sibling or related group. The genus was established by Limpricht in 1906.
Distribution
Rhytidiadelphus has a cosmopolitan distribution, with species occurring across temperate and boreal zones of the Northern Hemisphere, including Europe, North America, and Asia, as well as the Southern Hemisphere (New Zealand). Individual species vary in range: R. squarrosus is especially widespread in lowland and montane grasslands and lawns throughout Europe and North America, while R. loreus and R. triquetrus favour Atlantic and boreal woodland and heath habitats.
Ecology
Species of Rhytidiadelphus are ground-dwelling mosses that colonise a wide range of habitats including woodland floors, heaths, lawns, and montane grasslands. They form dense mats that retain moisture and contribute to the soil surface layer. R. squarrosus is a common lawn moss in temperate climates, often considered a weed in managed turf, while R. loreus and R. triquetrus are associated with undisturbed, humid habitats.
