Glow Crab

The glow crab is a strange species of crab that lives in the cold and turbulent waters north of Kos. Most of the time, the adults live over 1500 ft below sea level where they scavenge on falling food. They grow to be very large, almost 5ft in diameter and a legspan of nearly 6ft, and their carapace is extremely hard to withstand ocean pressure. They are capable of bioluminescence and use that to communicate with other crabs and defence from other deep sea creatures. They can weigh up to 35lb. Crabs have eight legs, six are used for locomotion, and the two front legs are evolved into powerful claws. Most crabs are left clawed with the lefthand claw being more developed, larger, and stronger than the nondominant claw. Right clawed crabs are rarer, though no one is exactly sure why. Some believe that the females select for the largest claw, and they view right clawed crabs as being weaker due to the less developed left claw. They also have two antennae which extend from the front of their mouths. They can feel small vibrations in the water and smell with specialized olfactory hairs that line the antennae. Every year, they migrate to shallow waters to breed. The males migrate up first and start the build circular nests in the sand. They add bits of sea moss and algae to make them look more appealing as a snack. They also dig channels in the sand leading to the nest. Males are very territorial and will fight each other for ownership of the nests. The females migrate so that they're ready to lay their eggs on the warmest day of the year in summer. They select males with large claws, bright bioluminescence, and the most appealing nest. She carries the egs on the underside of her body, tens of thousands at a time. It's a vulnerable time to mate because she needs to rear up on her back legs for the male to fertilize the eggs, and it's very easy for her to flip over. The nest helps protects her and gives her something to brace against. Once the eggs are fertilized, she sheds them and they float away in the current.
For the people who live on the island north of Kos, summer is crab hunting season. Every year, they trap crabs to eat as a rare delicacy. The eggs are especially tasty and have a salty flavor. Once the eggs have developed, they hatch into miniature versions of the adults and primarily swim eating plankton and microscopic organisms. They moult several times getting steadily larger until they reach a juvenile status when they descend to the seabed. There, they continue eating and living for the next few months. When they're about a year old, they're fully grown and migrate down to the deep ocean. It's unknown exactly how long the crabs can live for. The merfolk believe that they could be immortal, but most crabs will die of starvation or injuries.