Ianthella basta is a species of fan-shaped sea sponge in the class Demospongiae.

[3] A sponge measuring 1.7 m in height and 9.5 m circumference has been estimated to be about 8 years old.

[4][3] It is found on coral reefs in areas with rapid water flows.

[5] The sea cucumber (Synaptula lamperti) is closely associated with the sponge and makes use of certain nutrients exuded by it.

[6] Research is being undertaken on various metabolites and other biologically active constituents that are synthesized by the sponge.