Complex sentence: Spanish Dancer is the common name for the nudibranch species "Hexabranchus sanguineus", a large, strong swimming, brightly colored--red, hence "sanguineus", and often yellow--sea slug of wide distribution.
Split into simpler sentences: Spanish Dancer is the common name for the nudibranch species "Hexabranchus sanguineus". A large, strong swimming, brightly colored--red, hence "sanguineus", and often yellow--sea slug of wide distribution.