The Bobbit worm, Eunice Aphroditois

The Bobbit worm, Eunice aphroditois, is a ferocious underwater predator. The bobbit worm, also known as the Eunice worm, can be found in Secret bay in Bali, Indonesia - Police Pier & Nudie Retreat in Lembeh, Indonesia - and Mainit Muck or Basura in Anilao, Phillipines. It likes sandy and gravel substrates, that you would find on "muck" dives.

The bobbit worm has light and chemical receptors that cause it to lunge at fish when it thinks they are nearby. It has 5 antennae that house these sensory receptors.

Update - June 2009 - many bobbit worms have been seen at Air Prang dive site, Lembeh, Indonesia.

Bobbit Worm Myths and Facts

Bobbit worms are Polychaete worms in the phylum Annelida.

A common myth about the Bobbit Worm is that they got their name from the fact that the female worms cuts off the penis of the male worm after mating, and then feeds it to her young. This is actually not true.

Here's some facts from polychaete expert Leslie Harris at the Natural History Museum in Los Angeles:

First off, Polychaetes don't have penises or vaginas.  Most of them are what we call broadcast spawners which means the males & females spew out eggs & sperm into the water.  The eggs & sperm meet, the eggs get fertilized & start developing.  There is no such thing as mating/copulation not do males & females come into contact.   Only a very few species exhibit parental care which is minimal.  It consists of the female creating a mucus cocoon for the eggs & keeping it clean or brooding the eggs within her own tube.  Some species of Marphysa (which are in the same family as the genus Eunice)  produce egg cocoons. Females do not care for larvae or juveniles & they certainly do not feed them.

The association of "Bobbit" for Eunice aphroditois  has 2 possible origins.  The 1st - and the one I heard way back when - is that the outstretched jaws resemble scissors.  The 2nd is that the erect worms reminded someone of an unattached penis.

Bobbit worm claws and jaws

What you call the "claws" are jaws.  there are 2 types of jaw pieces - 1 pair of mandibles and 4-6 pairs of maxillae.  The big serrated hooked pieces are maxillae.  In the close up the 5 striped filaments are the antennae & palps - these carry the sensory receptors.  They have 1 pair of eyes at the base of the antennae but they may not play a big role in food capture.  Bobbit worms are ambush predators but if they're really hungry they will scavenge for food around the opening to their burrows.

Thank you Leslie!

Bobbit Worm Underwater Photo tips:

• Bobbit worms are nocturnal
• Don't shine your light on the bobbit worm for too long
• Use a good guide who has found them before
• The bobbit worm will often react to a light being shined on it only once or twice, lunging into the air, until it learns there is nothing there
• It doesn't seem to mind being closely approached, if you can get it to stay out
• Don't touch it, and don't get grabbed, the claws are very powerful and can injure you
• Be ready with your shots, because the worm can move very very fast.

Bobbit worm out of its hole

Bobbit worm grabbing a fish.. The fish disappeared less than a 1/2 second later, I got very very lucky with this shot.

Close-up showing the claws of the bobbit worm.

Bobbit worm lunging at a fish.

Further Reading

• Ultimate Muck-diving Critter List
• Photographing underwater marine life behavior
• Improving your underwater macro photography
• Dive destinations and locations for underwater photography
• Underwater camera settings for macro photography
• Lembeh straits underwater photography
• Anilao underwater photography
• Bali underwater photography

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