About Leptodictyum riparium (Hedw.) Warnst.
Leptodictyum riparium, commonly called Kneiff's feathermoss, streamside leptodictyum moss, or knapwort, is a moss species with a cosmopolitan distribution. It is absent only from the Pacific Islands and Australia. It grows commonly in Minnesota's lakes and rivers, and is also found in Mexico, Guatemala, the Bahamas, Cuba, Jamaica, Haiti, the Dominican Republic, Venezuela, Peru, and Brazil. This moss displays multiple distinct forms and can reach up to 30 centimeters in length. Its ovate leaves grow in two rows and are often pointed at the apex. Leptodictyum riparium has been recorded growing in an acidic mining lake, and can survive at pH as low as 1.6 in volcanic craters. It was once found growing alongside Eleocharis acicularis at a mining lake in Canada. The species contains high levels of phosphate, is easy to cultivate, and is used in aquariums. L. riparium is reported to tolerate a wide range of nutrient conditions, and its population increases as ammonia levels rise. It is also known to be able to use artificial light to grow in areas that have no natural light, such as Crystal Cave in Wisconsin.
