following six species: Ceratophyllum australe Griseb. Ceratophyllum demersum L. (rigid/common hornwort) – cosmopolitan Ceratophyllum echinatum A.Gray (spiny hornwort) – North America Ceratophyllum muricatum Cham. (prickly hornwort) – Near-cosmopolitan Ceratophyllum platyacanthum Cham. – Europe and Asia Ceratophyllum submersum L. (soft/tropical hornwort) – Europe, Middle-East, Central Asia, northern and central Africa, Florida, and Dominican Republic Ceratophyllum tanaiticum Sapjegin References External links Ceratophyllaceae of Mongolia in FloraGREIF Angiosperm genera Freshwater plants