Fionoidea is a superfamily of small sea slugs, aeolid nudibranchs.

Tritonia ingolfiana is a species of small sea slug, a dendronotid nudibranch.

Elysia pusilla is a species of small sea slug, a marine gastropod mollusk in the family Plakobranchidae.

A small sea slug about 1/2 inch long varying in colors from orange to a dark brown.

Placida is a genus of very small or minute sea slugs, marine opisthobranch gastropod mollusks in the family Limapontiidae.

Arminoidea is a superfamily of small sea slugs, marine gastropod molluscs in the clade Nudibranchia.

Aeolidioidea is a superfamily of small sea slugs, the aeolid nudibranchs.

Hydromyles is a taxonomic genus of small sea slugs, marine opisthobranch gastropod mollusks in the family Hydromylidae.

These extremely small sea slugs are meiofauna; they live among sand grains.

Baeolidia major is a small sea slug, an aeolid nudibranch, a marine gastropod mollusc in the family Aeolidiidae.