Anemone Hermit Crab: 15 Facts You Won't Believe!

Anemone hermit crab facts talk about their life history, life span, and their shells.

The anemone hermit crab (Dardanus pedunculatus) is a small hermit crab belonging to the family Diogenidae. This hermit crab is found in the Indo-Pacific region and is quite a fascinating marine creature. Sea anemones are attached to the anemone hermit crab's shell, providing it protection against predators. The sea anemone species that is found on the shells of anemone hermit crabs is Calliactis polypus.

The anemone hermit crab has a pale pink appearance with orange and white patches on its body. They have two antennae and white and red eyestalks. Their left claw is bigger in size compared to the right claw. Sea anemones protect the crab from larger predators with the help of their tentacles and threads. In turn, these sea anemones are provided with food and mobility. This is one of the greatest examples of symbiosis in the marine ecosystem. These crabs are found in intertidal areas in rocky or coral reefs. They are also seen in aquariums as pets. However, if kept as pets, a lot of care has to be taken to ensure their survival. Though this species does not have any immediate threats, climate change, and pet trades can cause harm to its population size.

To learn more about the anemone hermit crab, keep reading! You can also check out blue king crab facts and flower crab spider facts.

Anemone Hermit Crab

Fact File

What do they prey on?

Mollusks and other invertebrates

What do they eat?


Average litter size?


How much do they weigh?


How long are they?

4 in (10 cm)

How tall are they?


What do they look like?

Pale pink

Skin Type


What are their main threats?


What is their conservation status?

Not Evaluated

Where you'll find them

Coral reefs and rock reefs


The Indo-Pacific area





Scientific Name

Dardanus pedunculatus





Anemone Hermit Crab Interesting Facts

What type of animal is an anemone hermit crab?

The anemone hermit crab (Dardanus pedunculatus) is a species of hermit crab forming a symbiotic relationship with sea anemones such as the anemone, Calliactis polypus. This hermit crab has several sea anemones attached to its shell.

What class of animal does an anemone hermit crab belong to?

The anemone hermit crab belongs to the class Malacostraca which contains crabs, lobsters, and shrimps. They are a part of the Diogenidae family.

How many anemone hermit crabs are there in the world?

The exact population of anemone hermit crabs has not been studied. In general, some species of hermit crabs are rare, while some are pretty common and have a stable population.

Where does an anemone hermit crab live?

The anemone hermit crab's geographical range covers the Indo-Pacific area. Their distribution is quite broad and far-ranging. They are observed from the Seychelles in the west to Hawaii in the east. They are also found along the coasts of Australia.

What is an anemone hermit crab's habitat?

The habitat of an anemone hermit crab is characterized by coral reefs and rock reefs. This species can be found at depths of 89 ft (27 m) in their natural habitat. They are known to inhabit intertidal areas and can be found in the seagrass of sandy bottoms.

Who does the anemone hermit crab live with?

The social behavior of hermit crabs shows that they are social creatures. They are usually found in large groups that can have up to 100 crabs. Even as pets, it is always advised to pair up hermit crabs since they need companionship. The same social behaviors can be assumed to be followed by the anemone hermit crab.

How long does an anemone hermit crab live?

Though the lifespan of the anemone hermit crab is not known, hermit crabs can live for more than 30 years in their natural habitat. However, in captivity, their life span is much shorter.

How do they reproduce?

Male anemone hermit crabs can tell when a female anemone hermit crab is ready for mating based on chemical signals produced by the female. While the exact number of eggs laid by the female anemone hermit crab is not known, female hermit crabs are known to lay between 800-50,000 eggs. After successful fertilization, the eggs are stored on the undersides of the shells. Upon hatching, the larvae go through a planktonic phase before they find their own shells.

What is their conservation status?

The conservation status of anemone hermit crabs is Not Evaluated by the International Union For Conservation Of Nature (IUCN). They seem to have no threats. However, climate change and over-exploitation in the pet trade can cause harm to their population.

Anemone Hermit Crab Fun Facts

What does an anemone hermit crab look like?

The anemone hermit crab (Dardanus pedunculatus) is seen with a distinct appearance, mainly due to the sea anemones on its shell. Their body is pale pink in color with orange and white patches. The eyes appear a lighter shade of green, while the eyestalks are white and red. They are provided with two antennae, one of which aids the anemone hermit crab in sensing its surrounding. Their legs protrude from their shell. The legs end in claws and the left claw is bigger in size than the one on the right. Their entire body and legs are covered with bristles that are light brown in color.

The anemone hermit crab is a small hermit crab species.

How cute are they?

More than cute, this is a fascinating marine species that shows us the various kinds of relationships that exist in nature.

How do they communicate?

The methods of communication in the anemone hermit crab are limited to chemical or mechanical means. It has been observed that hermit crabs relay information related to any potential danger to the sea anemones on their shells via chemical or physical means. In response to this warning, the sea anemones spread their stinging threads over the hermit crab and provide protection. Additionally, the female anemone hermit crab releases pheromones that are picked up by the male. This lets the male know the female is fertile.

How big is an anemone hermit crab?

The anemone hermit crab is a small species and their length is about 4 in (10 cm). This size is comparable to the length of a Sally lightfoot crab, a similar crab species, which measures between 3-5 in (8-12 cm). Evidently, the Sally lightfoot crab can grow to be three times bigger than the anemone hermit crab.

How fast can an anemone hermit crab run?

The exact speed of an anemone hermit crab is not known. However, in general, hermit crabs are capable of moving 4 ips (0.1 mps). It is essential to note that hermit crabs resort to hiding under their shell as opposed to running long distances when threatened.

How much does an anemone hermit crab weigh?

The exact weight of the anemone hermit crab is unknown. Generally speaking, hermit crabs weigh between 7-18 oz (199-510 g). Hermit crab species are much lighter in weight when compared to the king crab, which weighs between 4.4-18 lb (2-8 kg).

What are the male and female names of the species?

Male and female anemone hermit crabs are known as male anemone hermit crabs and female anemone hermit crabs.

What would you call a baby anemone hermit crab?

A baby anemone hermit crab is known as a larva.

What do they eat?

The anemone hermit crab is best described as being carnivorous. Various kinds of mollusks and invertebrates are their most common food materials. They are also known to scavenge for food. The symbiotic relationship between the crab and the sea anemone aids in the process of the anemones getting their food. They usually feed on whatever is left by the crab. The hermit crab is sometimes observed to eat the sea anemones on its own shell and also those on the shell of other hermit crabs. However, sea anemones never eat hermit crabs.

Are they poisonous?

In the symbiotic relationship between sea anemones (Calliactis polypus) and the hermit crab, the crab is not poisonous. However, the anemones are poisonous. Their tentacles contain a poison which provides protection to the hermit crab against predators. There are no known instances of an anemone hermit crab being dangerous to humans.

Would they make a good pet?

Sea anemone hermit crabs are found as pets in many aquariums. They have a semi-aggressive temperament and require a lot of food to thrive. However, it is advised against buying hermit crabs such as this species because they do not survive for long if they are not taken care of properly.

Did you know...

The shells which are found on hermit crabs are made by other marine gastropods. Hermit crabs do not make their own shell but live in 'borrowed' shells which they find lying in their habitat. They have been seen to exchange their shells with other hermit crabs too.

What is the relationship between a hermit crab and a sea anemone?

The relationship between the hermit crab and sea anemone (Calliactis polypus) in the anemone hermit crab (Dardanus pedunculatus) is the perfect example of a symbiotic relationship. Anemones are collected by the crab at night and placed on their shell. The sea anemone species provides ample protection to the hermit crab by spreading its poisonous threads and tentacles over the shell of the crab. With anemones on its shell, the hermit crab has a significant defense against large predators.

The sea anemone gets food and mobility because of the hermit crab. They feed on whatever food is left by the crab and also get to cover large areas without having to move on their own as they are attached to the shell of the crab. These two animals definitely enjoy the benefits of being a part of each other.

Will a hermit crab die without a shell?

Yes, a hermit crab will die without its shell. This is because the shell of a hermit crab forms a barrier around its exoskeleton which is pretty sensitive. Rhe shell protects the crab from damages that can be caused by light, heat, and air. The shell also prevents the body of the crab from becoming too dry. However, hermit crabs do leave their shells from time to time in order to molt. Once molting is complete, they re-shell themselves.

Here at Kidadl, we have carefully created lots of interesting family-friendly animal facts for everyone to discover! Learn more about some other arthropods from our eight-spotted forester moth facts and ebony jewelwing facts pages.

You can even occupy yourself at home by coloring in one of our free printable hermit crab label parts coloring pages.



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