Anemone Hermit Crab

Anemone Hermit Crab

This hermit crab is found in the Red Sea around the surface of the water and at deep depth on the coral reefs. They are approximately 10cm. The Anemone Hermit Crab is usually easy to spot by the anemones that they carry on their shells. The body of the crab is a pale pinkish color with white and orange blotches. The eye stalks are red and white whilst their actual eye color is almost green, their bodies and legs are covered in light brown colored bristles. They have two sets of antennae, one short pair in the middle with sensory organs and the other pair is longer on the outside. Usually only the legs and head are seen protruding from the shell. The first set of legs has claws, the left one being larger than the right. Aside from being used for predation and self-defense, the claws are also used to seal themselves into their shell when threatened. The second and third legs are used for walking. The rear of the body is adapted to fold into the shell. The Anemone hermit crab grows up to 5 cm in width.

It may seem hard on the surface due to its head and pinsters but it actually has a soft underbelly. It lives in a shell that it covers in anemones for further protection. Anemone hermit crabs are usually only seen at night. During the day they tend to hide in crevices and under rocks. Being quite shy they tend to scuttle off when lit up by dive lights at night. They have developed the skill of coaxing the anemones off rocks and onto their shells. When they change shells they remove the anemones off the old shell by gripping them with their claws and slowly massaging the base of the anemone until it lets go. They then place it on their new shell. When the anemones are disturbed they give off sticky threads which are distasteful to predators therefore providing great protection for the crab.

The anemone's stinging tentacles keep the hermit crab from becoming an easy lunch for a hungry fish. And, when the hermit crab does not move it blends in easily with the reef. The anemones benefit by being taken to many different locations to feed as the crab moves around the reef. Anemone Hermit crabs use two species of anemone on their shells. The larger anemone is Calliactis polypus and the smaller flatter anemone is Verrillactis paguri. When both species of anemone are on the shell then the crabs usually place the Calliactis polypus on the outer part of the shell. There are amphipods of an unknown species that inhabit these anemones and live on the shells

They are usually found on coral and rocks in depths of up to 40meters. This crab is carnivorous and mainly a scavenger, it will break open and eat any mollusk that it possibly can. 

The males are able to detect when a female is fertile and they will often hold onto the female until she is ready to mate. The eggs are kept on the underside of the female in her shell.