70+, see text Polymastia is a genus of sea sponges containing about 30 species.

[1] These are small to large encrusting or dome-shaped sponges with a smooth surface having many teat-shaped projections (papillae).

In areas of strong wave action, this genus does not grow the teat structures, but instead grows in a corrugated form.

[2] The following species are recognised:[3]

This article about a demosponge is a stub.