Hornwort

[hawrn-wurt, -wawrt] /ˈhɔrnˌwɜrt, -ˌwɔrt/

noun
1.
any aquatic plant of the genus Ceratophyllum, found in ponds and slow streams.
/ˈhɔːnˌwɜːt/
noun
1.
any aquatic plant of the genus Ceratophyllum, forming submerged branching masses in ponds and slow-flowing streams: family Ceratophyllaceae
2.
any of a group of bryophytes belonging to the phylum Anthocerophyta, resembling liverworts but with hornlike sporophytes
hornwort
(hôrn’wûrt’, -wôrt’)
Any of about 100 species of small bryophyte plants belonging to the phylum Anthocerophyta. Unlike liverworts but like mosses, hornwort sporophytes have stomata. The hornwort gametophyte consists of a low thallus, out of which numerous slender, upright sporophytes tipped with sporangia grow. The sporophyte has a meristem that elongates the sporophyte with new growth, a feature that distinguishes the plant from the other bryophytes. The name of the hornworts was suggested by the hornlike appearance of the sporophytes. See more at bryophyte.