Fontinalis antipyretica

Fontinalis antipyretica, the antifever fontinalis moss, greater water-moss, or common water moss, is a species of submerged aquatic moss belonging to the subclass Bryidae. It is found in both still and flowing freshwater in Europe, Asia, North America and parts of Africa. Fontinalis antipyretica has branched, trailing stems that are triangular in cross-section and may be as long as 60 cm (24 in). The leaves are quite stiff and are arranged in three overlapping rows. Each leaf is lance-shaped or egg-shaped, with a keel and a sharp point, some 4 to 9 mm (0.16 to 0.35 in) long. There are no flowers but minute spores are sometimes produced in smooth sporangia (capsules) between 2 and 2.6 mm (0.08 and 0.10 in) long. Fontinalis antipyretica is found in North America as far south as Pennsylvania and Arizona, and also in Europe, Asia and parts of Africa. It grows attached to submerged rocks in fast-flowing water. It also occurs attached to the substrate in lakes and as floating masses in still water, and may be cast up on beaches at the waterside. It thrives in shady positions and prefers acid water, a pH of around 8.4 being the maximum tolerated. Reproduction is mostly by stolons or by the rooting of detached fragments. Sexual reproduction does also occur, in the spring in North America, but is relatively unimportant as a means of reproduction. Individual plants are either male or female and the capsules housing the spores are seldom observed. Fontinalis antipyretica grows in large clumps and mats and provides refuge for fish eggs and fry. Numerous invertebrates shelter among the fronds; Chironomid larvae hide in the bases of the leaves and mayfly, caddisfly and stonefly larvae cling to the fronds, and in fast-flowing water black fly larvae are often present. Diatoms and other microscopic algae grow epiphytically on the fronds. It has been found that Fontinalis antipyretica can adsorb cadmium and zinc, with maximum biosorption of cadmium being 28 milligrams (0.43 gr) per gram of dried moss, and of zinc 11 to 15 milligrams (0.17 to 0.23 gr) (depending on water temperature). The biosorption of cadmium was unaffected by the hardness of the water but that of zinc was affected by rising calcium levels. Fontinalis antipyretica was traditionally used in cool-water aquaria, but in tropical aquaria the similarly-structured 'Java moss' ( a Vesicularia species) takes its place.