March 18, 2015
A group of bizarre-looking sea creatures that have been around for more than 300 million years has gone on display at Portsmouth’s Blue Reef Aquarium.
Five baby horseshoe crabs have taken up residence in the Southsea wildlife attraction’s clownfish display. Despite their name, horseshoe crabs are actually not crustaceans at all but a type of marine arachnid and more closely related to spiders and scorpions. They are the last surviving members of a large group of animals that are now extinct and only found as fossils.
Blue Reef’s Adam Makinson said: “We have put the crabs into our tropical clownfish display, which is also home to a number of living anemones. The crabs burrow through the sand searching for small organisms to feed on, making tracks and ploughing up the surface as they go keeping the substrate that sits in some tough-to-reach areas clean and bright. It’s a great example of natural behaviour being used instead of mechanical filters to keep a display clean,” he added.
“Horseshoe crabs have been living in our seas for an estimated 300 million years – long before the dinosaurs. Their appearance is similar to the prehistoric and extinct trilobite. A distinctive feature of the horseshoe is its long tail-like spine – which is known as a telson. Although it looks dangerous it is actually not a weapon at all but a way for the animal to right itself if it gets turned on its back.”
Horseshoe crabs have four pairs of walking legs with a claw at the end of each. There is also a fifth pair that helps the crab lurch forward. Its mouth is actually located in between the base of the legs and the horseshoe crab can only eat when it is moving. There are four species of horseshoe crabs found in different locations around the world. The mangrove horseshoe crab is found in south east Asia, the Japanese horseshoe crab along east Asian coasts, the Atlantic horseshoe crab along the northwest Atlantic coast and in the Gulf of Mexico, and the coastal horseshoe crab in south and southeast Asia. The medical profession uses an extract from the horseshoe crab’s blue, copper-based blood to test the purity of medicines. Certain properties of the shell have also been used to speed blood clotting.
Issued by the Blue Reef Aquarium. For more information please contact Adam Makinson or Jenna MacFarlane on 02392 875222.