Kalmar "Coelenterata" tsohuwar ƙungiyar haraji ce wacce ba a amfani da ita a cikin ilimin halitta na zamani. An yi amfani da shi a baya don kwatanta phylum na dabbobin da ba su da invertebrate na ruwa waɗanda suka haɗa da jellyfish, murjani, anemones na teku, da hydroids.A yanzu ana amfani da kalmar "Cnidaria" ga wannan rukunin dabbobi, waɗanda ke da siffa. ta hanyar samun ƙwararrun ƙwayoyin cuta da ake kira cnidocytes. Cnidarians yawanci suna da simmetry na radial, tsarin jiki mai kama da jakar, da kuma bakin tsakiya mai kewaye da tanti. Ana samun su a cikin ruwan gishiri da mahalli na ruwa kuma suna taka muhimmiyar rawa a matsayin mafarauta, ganima, da masu ginin reef.