Ceratophyllum Linnaeus. Common name: Hornwort, Coontail.
A genus of about 6 species, aquatic herbs, of cosmopolitan distribution.
ID notes: Ceratophyllum is sometimes mistaken for superficially somewhat similar, aquatics, such as Cabomba (Cabombaceae), Utricularia (Lentibulariaceae), and Myriophyllum (Haloragaceae). Cabomba has the leaves opposite (rather than whorled), dichotomously divided (like Ceratophyllum), but the divisions lacking the marginal denticles of Ceratophyllum, and on a 1-3 cm long petiole (vs. sessile or on a petiole 0-2 mm long). Utricularia has the leaves sometimes dichotomously divided, but the divisions are usually irregular, the leaves are alternate (in most species), and bladder traps are present. Myriophyllum has the leaves pectinately rather than dichotomously divided.
References: Les (1985); Les (1986); Les (1988a); Les (1988b); Les (1988c); Les (1989); Les (1993) In Kubitzki, Rohwer, & Bittrich (1993); Les (1997) In Flora of North America Editorial Committee (1997); Szalontai et al. (2018); Wilmot-Dear (1985). Show full citations.
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no rights reserved, uploaded by Trix Niernberger | Ceratophyllum echinatum source | Original Image ⭷
© Michelle W., some rights reserved (CC BY), uploaded by Michelle W. | Ceratophyllum demersum source | Original Image ⭷
© Thomas Gyselinck, some rights reserved (CC BY), uploaded by Thomas Gyselinck | Ceratophyllum demersum source | Original Image ⭷
© Mary Keim, some rights reserved (CC BY-NC-SA) | Ceratophyllum demersum source | Original Image ⭷Feedback
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