Ceratosoma brevicaudatum Abraham, 1876

On might argue that Ceratosoma brevicaudatum is one of the most flamboyantly beautiful dorid nudibranchs from the Indo-Pacific. If there was ever an aposomaticly colored species, this is it. Most of the Ceratosomaids display wild warning colors, giving notice to predators that they have a wicked defense structure. This is the horn situated behind the gill. The name brevicaudatum means 'short tail' in Latin, which is a reference to this very short dorsal horn.

Bill Rudman, on his Forum, explains "that this horn has an interesting defensive function because it is where the animal stores distasteful and noxious chemicals it has removed from its sponge food. The horn appears to act as a sacrificial lure, tempting fish to take a bite. When or if they do they get a mouth full of nasty chemicals which teach them to leave Ceratosoma alone. As the 'horn' has no other function, the slug can live quite happily without it."

Bill goes on to say - "It seems that Ceratosoma brevicaudatum represents an early stage in the evolution of the dorsal horn. It is packed full of noxious chemicals and is usually more brightly coloured thyan the rest of the body - again acting as a lure."

Merry's photos of the gorgeous species knock the ball out of the house when it comes to a breathtaking example of an aposomatic species.

Thanks Merry, and Jim Black also for his previous submission.