Fontinalaceae

Fontinalaceae is a family of mosses in the class Bryopsida, order Hypnales. The family is composed primarily of aquatic mosses, with Fontinalis as its best-known genus, commonly called fountain moss. Species are distributed worldwide, inhabiting freshwater ecosystems such as streams, rivers, and cool springs, often attaching to submerged rocks, logs, or aquatic vegetation.

Morphology and growth form: Members are typically aquatic or semi-aquatic mosses that form slender, creeping shoots. Leaves are narrow, flexible, and closely pressed to the stem, giving the shoot a flattened appearance. The growth form ranges from simple to branched mats that cling to substrates in flowing or still water.

Ecology and habitat: Fontinalaceae species tolerate a range of water velocities and light conditions but prefer clean, well-oxygenated waters. They contribute to the structure of freshwater microhabitats and may support periphyton communities; they can also be used in studies of water quality and stream ecology.

Reproduction and life cycle: As with other mosses, Fontinalaceae undergo alternation of generations, with a haploid gametophyte producing male and female reproductive structures, and a diploid sporophyte developing after fertilization to produce spores that disperse to form new plants. Fragmentation and vegetative spread are common in stable habitats.

Genera and classification: The best-known genus is Fontinalis, and the family includes several other genera recognized in various classifications. Taxonomic placement has varied with revisions; in modern classifications it is placed within Hypnales and Bryopsida.