Long-beaked Water Feather-moss - Rhynchostegium riparioides

P. riparioides occurs in or near water and varies considerably depending on the conditions. In clean water, it may form large patches of long, sparingly branched shoots (to 10 cm or more), the older parts of the stems often becoming denuded. At other times, especially in small and polluted streams, it may occur only as small, scruffy shoots. Important characters are the rather large leaves (1.5 to 2.5 mm long), broadly egg-shaped, narrowed at the base, broadly pointed at the tip, and standing out from the stem when moist and dry. They have a long, single nerve and finely but distinctly toothed margins. The shoot tip of P. riparioides tends to look broad and flattened, which is not the case in related species. Capsules (2 mm long) are often present and these are especially useful for confirming scrappy forms of the species. The lid has a beak about 2 mm long, and the seta is smooth.

Occurs in or near water where it grows submerged or semi-submerged for at least part of the year on stones, tree roots and wood by lowland streams and rivers, but also in upland streams where the substrate is not too acidic. It grows best in and by running water, but may occur sparsely in ditches and by canals, ponds, drains and similar places.

All year round.

Widespread and fairly frequent in Britain.

Frequent in Leicestershire and Rutland by water.