Polybranchia orientalis | Oriental Butterfly Seaslug

This sap-sucking sea slug is common in the Indo-Pacific region but is often not noticed due to its camouflage. The color of its cerata depends on the algae it feeds on, but they all contain a finely branched network of digestive gland ducts. Similar to other Cyerce and Polybranchia species, Polybranchia orientalis has a defensive mechanism wherein it casts off its cerata when disturbed (they can grow back after a while). Its head and rhinophores are often concealed by the cerata.