This is not a specially designed birthday cake. It is not a palette too – it is called Clown Nudibranch. This bright and uniquely colored sea slug can be found in the intertidal zones of temperate southern Australia and northern New Zealand.
Nudibranch: Flabellina goddardi, the "Fiery Sea Slug", discovered in 2008 by marine biologist Jeff Goddard. It lays a lacy egg mass that hatch into tiny babies. The egg mass is formed that way so that each baby receives enough oxygen.