English Radiocyatha Cited by user Fanboyphilosopher on 04 May 2023 Radiocyatha is an extinct group of sponge-like animals which lived in the early to mid-Cambrian Period (Tommotian to Toyonian).
English Heteractinida Cited by user Monster Iestyn on 28 Sep 2019 The Heteractinids are a grade of sponges that are paraphyletic with respect to Hexactinellida.
English Eiffeliidae Cited by user Monster Iestyn on 27 Sep 2019 Eiffeliidae is an extinct family of sponges.