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Eunice aphroditois is rainbow, terrifying

This article was published in Scientific American’s former blog network and reflects the views of the author, not necessarily those of Scientific American


If Hell's a glittery rainbow party of terror, you'll find this guy having post-drinks in the pub at 10am.

This is Eunice aphroditois, otherwise known as a bobbit worm. Apparently around 20 years ago, an underwater photographer thought it and other species in the Eunice genus were reminiscent enough of the Bobbitt family incident of 1993 to warrant the nickname, according to a 2011 paper in Revista de Biología Tropical. The incident involved Lorena Bobbitt chopping nearly half her husband’s penis off, and E. aphroditois is similar, said biologist Sergio Salazar-Vallejo from Mexico's El Colegio de la Frontera Sur, "because either the widely open jaw pieces resemble scissors, or because the exposed portion resembles an erect penis", referring to the way these marine worms bury themselves in the sea floor and expose just a fraction of their very long bodies for hunting.

This explanation cannot be confirmed, however, as a reply by Anja Schulze from the Department of Marine Biology at the Texas A&M University noted that it doesn’t make sense, seeing as Lorena Bobbitt’s weapon of choice was a knife, not scissors. Another possibility is that these worms got their nickname from a myth that after mating, the female cuts off the male’s penis and feeds it to her young. But these worms don’t have penises, and their levels of parental care are minimal at best.


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It doesn't really matter where E. aphroditois got its nickname from, because it's fascinating enough without all the castration mythology. It lives on the sea floor at depths of 10 to 40 m, and has five antennae to sense its prey, such as smaller worms and fish, which it catches with a complex feeding apparatus called a pharynx. The pharynx can turn inside-out, like glove fingers, and has strong, sharp mandibles on the end. Sometimes its prey is cut clean in half because of the speed and strength of E. aphroditois' attacks, and it can inflict a nasty bite if a human gets too close. Once the prey is caught, this long-living nocturnal worm will shoot back into its burrow to feed. It also feeds off seaweed and other sea plants and when prey is scarce, will scavenge for morsels around the surface of its burrow.

The species' colouring ranges from a dark brown to a golden red, and has a stunning purple iridescence. Like in many other Eunice species, a white or pale ring runs around its forth body segment.

E. aphroditois is found all over the world where the ocean is warm, and is noted for its unusually large body size and length. Since the 19th century, scientists have recognised it as having one of, if not the, longest bodies among the polychaete worms - a class of highly segmented, mostly marine worms including the Christmas tree and Pompeii worms. Their average length is one metre, and specimens measuring a whopping three metres have been discovered in the waters of the Iberian Peninsula, Australia and Japan.

According to a report led by Hiro'omi Uchida, assistant director of the Kushimoto Marine Park Centre in Kushimoto, Japan, a three-metre-long specimen was found hiding in one of the 120 floats of a mooring raft in Japan's Seto Fishing Harbour in 2009. "It is uncertain when the individual first entered the mooring raft and fish corral during the 13 years the structure sat in the harbour. It is also uncertain whether the worm arrived by larval settlement or at a semi-adult stage of development," wrote Uchida. "Nonetheless, the individual surely had been living in its comfortable floating home for a quite a long time." The worm measured 299 cm, weighed 433 g, and had 673 segments, making it one of the largest specimens of E. aphroditois ever found.

That same year, a metre-long E. aphroditois was found to be wreaking havoc on one of the reef display tanks of Newquay's Blue Reef Aquarium in the UK, chopping the coral up and killing its inhabitants. The entire tank had to be emptied of its coral, rocks and plants, after the aquarium staff’s traps failed to turn up the culprit. The aquarium's curator, Matt Slater, told the Daily Mail, 'Something was guzzling our reef but we had no idea what. We also found an injured Tang Fish, so we laid traps, but they got ripped apart in the night. That worm must have obliterated the traps. The bait was full of hooks which he must have just digested.' Turns out the worm likely hitched a ride into the tank by hiding in a piece of coral when young, and secretly grew enormous over a number of years. Slater also mentioned that E. aphroditois is covered in thousands of bristles that are capable of inflicting a sting ‘resulting in permanent numbness’ in humans.

Here's another stunning picture of E. aphroditois, and here’s a video of its incredible hunting skills, and also the super-creepy frog fish:

* Jenny Huang's Flickr site

Order my new book, Zombie Tits, Astronaut Fish and Other Weird Animals, here.

About Becky Crew

Bec Crew is a Sydney-based science writer and award-winning blogger. She is the author of 'Zombie Tits, Astronaut Fish and Other Weird Animals' (NewSouth Press).

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