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.

The growth form is procumbent but small, young plants can attach themselves closely to rocks and appear flattened.

In the UK, mosses that grow in similar habitats and may be confused with P. ripariodes include the aquatic genus Brachythecium and Leptodictyum riparium.

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