Instead they are sacoglossans , commonly known as sap - sucking slugs .
These animals are colorful sea slugs , and they can superficially resemble nudibranchs , but are not very closely related to them .
Instead animals are sacoglossans , commonly known as sap - sucking slugs .
These animals are colorful sea slugs , and they can superficially resemble nudibranchs , but are not very closely related to them .