About Hippuris tetraphylla L.fil.
Previously, the genus Hippuris, commonly known as mare's tail, was the only genus placed in the plant family Hippuridaceae. After genetic research conducted by the Angiosperm Phylogeny Group, this genus has been transferred to the family Plantaginaceae, and Hippuridaceae is now treated as a synonym of Plantaginaceae. Depending on different taxonomic interpretations, the genus contains between one and three species. Some authorities recognize only one species from the three listed below, and classify the other two as synonyms of the accepted species: Common mare's tail (Hippuris vulgaris), Mountain mare's tail (Hippuris montana), and Fourleaf mare's tail (Hippuris tetraphylla). All Hippuris species are aquatic plants that grow in shallow ponds and in both slow-moving and fast-flowing streams. Though Hippuris is a flowering plant, it is sometimes incorrectly confused with the non-flowering plant horsetail.