by Natalie Pogar
The Bobbit Worm, although rumored to have been named after an unfortunate event in the 90’s, is true to have bear-trap jaws and a surreal looking iridescent body. With the Bobbit Worm’s length being 1-3 metres, its width is about 2 ½-3 centimeters. There have been Bobbit worms reported with 10 different color morphs found on the Scandinavian Coasts. Its colors range from light orange to grey to metallic with an iridescent shell and five banded antennae. Two out of the five antennae are called palps, which are segmented appendages close to the mouth that sense touch and taste. They have two types of mandibles, one is the actual jaws and 2 are the 4-6 maxillae which are the bigger serrated parts, so sharp that it can cut a fish in half. On the Bobbit worm’s prostomium, it has two eyes that are almost completely blind near the mouth and the peristomium which is the beginning segment of a long segmented body. There are small appendages coming from each segment of the body that look like legs but are in fact bristles made of chitin, a fibrous substance, that helps this creature’s locomotion and sensation. Each time a Bobbit Worm grows, a segment is added to their body reaching the shield or end segment called the pygidium. When a Bobbit Worm is severed or ejected from itself out of fear, it can still live and grow back all parts it is missing, making a genetic identical match. It is reported that at times, more than one part of a Bobbit Worm can survive when this happens. Although the Bobbit Worm’s size is tremendously long, it only shows about 1-6 inches of their body that peeks out from their holes in the substrate of the oceans floor.
The Bobbit Worm’s bristles play a large role in their movement, helping them to dig and crawl along the ocean floor. When burrowing down into the sediment to make their tunnels, their bristles dig and boost them further and further until their whole body can fit in snuggly. When hunting for food, the Bobbit Worm will have just its antennae showing through to appear as though they are small worms coming out of the ground to attract unsuspecting prey. If given strong signals from its antennae that there is potential prey, the Bobbit Worm’s bristles will grab onto the walls of the hole and propel itself out incredibly fast. The bristles move in an up and down motion to get the speed it needs to jut out of its hole.
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