Tetractinellida

plural noun

Te·​trac·​ti·​nel·​li·​da

in some classifications

: a subclass or other division of Demospongiae comprising sponges with siliceous 4-rayed spicules or sometimes with desmas or without spicules

Word History

Etymology

New Latin, from Tetractina, a division of sponges in some classifications (from tetra- + -actina -actine) + -ella + -ida

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