''Platyhypnidium riparioides'', the long-beaked water feathermoss, is a species of aquatic

moss Mosses are small, non-vascular flowerless plants in the taxonomic division Bryophyta (, ) '' sensu stricto''. Bryophyta (''sensu lato'', Schimp. 1879) may also refer to the parent group bryophytes, which comprise liverworts, mosses, and hor ...

commonly found in many regions. This species is among the largest aquatic mosses growing up to 15 cm long. ''P. riparioides'' grows in a procumbent or pendulous fashion along rocks and tree roots and may form extensive lax mats of many intermingled plants. It is widely distributed South of the Arctic and can grow abundantly in suitable areas.

Description

''Platyhypnidium ripariodes'' is among the larger northern hemisphere mosses with leaves up to 8mm long and plants growing up to 15 cm long. In the UK, plants commonly produce calyptra with relatively long curving lids. The leaf tip is acute, leaf margins are plane, slightly denticulate towards tip, mid-leaf cells are large, costa or the central stork of the leaf extends nearly to leaf tip. The growth form is procumbent but small, young plants can attach themselves closely to rocks and appear flattened.

Identification

''Platyhypnidium ripariodes'' diagnostic features include its comparatively large size, up to 15 cm long, large leaf size up to 8 mm with elongated mid-leaf cells. Capsules are abundant and frequently produced and feature long curving lid. In the UK, mosses that grow in similar habitats and may be confused with ''P. ripariodes'' include the aquatic genus ''Brachythecium'' and ''Leptodictyum riparium''. All these mosses are platycarpus, have a single nerve per leaf and overlap in size but can be separate by leaf shape, cell structure and growth form.

Distribution

Wide global distribution found South of the Arctic polar region in flowing freshwater mainly in Northern Hemisphere. Found commonly in the

British Isles The British Isles are a group of islands in the North Atlantic Ocean off the north-western coast of continental Europe, consisting of the islands of Great Britain, Ireland, the Isle of Man, the Inner and Outer Hebrides, the Northern Isles, ...

References

{{Taxonbar, from=Q7202612 Brachytheciaceae