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Kidadl Team

AUGUST 06, 2021

Decorator Crab: 21 Facts You Won’t Believe!

Learn amazing decorator crab facts here.

The spider decorator crab is a marine animal in the family Majoidea that use numerous materials from its surrounding to decorate its body. It mostly sticks sedentary plant and animal species on the entire body., which provides this animal an excellent camouflage against the background. This technique also provides protection from various predators. Some of the ornaments include seaweed, sponge, shell, alga, and coral. They stick these ornaments through hair-like structures. Decorator crabs and sponges go along together as these crabs use sponges to decorate themselves. They have many legs to help them move around, depending on the species they belong to. It is very uncommon for people to eat these crabs as a delicacy.

The spider decorator crab phylum is Arthropoda. Humans keep this animal in the aquarium at various places because of its unique appearance. Although, in the aquarium, they need special requirements like their natural habitat. For their habitat, they prefer rocky shores in the sea and coral reefs. Sometimes, these crabs attach some poisonous organisms which help them to protect themselves from predators. The spider decorator crab food includes clams, mussels, mollusks, and other vertebrates. While most of the species have a good temperament, some of them become offensive at times.

If you like crabs, you can also check out king crab facts and hermit crab facts.

Decorator Crab Interesting Facts

What type of animal is a decorator crab?

The decorator crab is a type of crab and is also known as spider crab, a marine creature that uses various plants and animals to decorate itself.

What class of animal does a decorator crab belong to?

The spider decorator crab belongs to the class Malacostraca in the phylum Arthropoda.

How many decorator crabs are there in the world?

There are around 700 species of these crabs. Some of the crabs include Acanthonyx dentatus, Macropodia rostrata, Oregonia gracilis, Libinia emarginata, Achaeus spinosus, and Camposcia retusa. The total population size of these crabs is unknown.

Where does a decorator crab live?

It is found all over the world's oceans and seas. It can be seen at night because of the reflection of its eyes in the sea. The camouflage of this animal is so good that it is arduous to recognize it during the day until it movies. If one is lucky enough to spot this creature, it is extremely hard to keep it in sight.

What is a decorator crab's habitat?

There are many different species of these crabs that inhabit intertidal rocky shores in the sea. They are nocturnal creatures that hunt and scavenge at night. In the aquarium, they hunt when the lights are off. However, in the roof aquarium, they collect algae, soft corals, and smaller invertebrates to decorate them on the shell, which provides these animals a great look and protection through camouflage. This activity sometimes results in damage to the corals in a small aquarium, but in the bigger reef aquarium, it helps proliferate these corals throughout the aquarium. In general, all these species are very peaceful that have a unique appearance. They execute numerous advantageous roles within a healthy reef aquarium. One species, Oregonia gracilis founds at a depth of 1,430 ft (436 m). Its distribution range from North Alaska to Japan. Another species, Oregonia bifurca usually lives at 1,650 ft (500m). Other species thrive near it as well, including Scyra actuirons and Hyas lyratus. They prefer coral reefs and rocky shores as their habitat.

Who does a decorator crab live with?

This animal performs mutualism with hydrozoans and other corals. It uses sea urchins and anemones as camouflage. Interestingly, some larger decorator crabs are strong enough to defend themselves and therefore do not decorate themselves. However, some plants and animals clasp onto the crabs anyway for their protection.

How long does a decorator crab live?

The decorator crab's lifespan has not been estimated yet.

How do they reproduce?

There is not much information available regarding the reproduction of decorator crabs. Like other crustaceans, male crabs fertilized the eggs in this species. The fertilization in spider crabs occurs inside the female body. In their lifecycle, all larvae go through a planktonic stage before metamorphosis into adult crabs.

What is their conservation status?

The conservation status of decorator crabs is unknown.

Decorator Crab Fun Facts

What does a decorator crab look like?

Decorator crabs have a colorful shell.

Decorator crab characteristics include a tough exoskeleton composed of chiton, claws, and four pairs of legs. Many species have tiny spikes, thick hair, or barbs on their entire shell which helps them to stick various ornaments to camouflage against the background and protect themselves. When they entirely decorate themselves, it is difficult to spot them. You can only locate them at night as their eyes reflect from the light of dive torches. Like other crustaceans, decorator crabs molt and change shells which needs a completely new decoration on each molt. Their average body size is around 2 in (5 cm). Sometimes, crabs use their old shell decorations to decorate their new shells which preserve their precious time. During one phase of the crab's life, around 75% of the spider decorator crabs embellish at least one part of their body, which means a total of 675 species out of 700 species have the capability to decorate themselves. The camouflage activities involve changing body colors and shapes with the help of ornaments with the help of stiff hair-like hooks, called satae, to protect themselves from predators. For instance, the Camposcia decorator crab decorates its brown body with rocks, sponges, shells, algae, rocks, and corals. They cover their bodies with a broad range of ornaments.

How cute are they?

With different ornaments on their bodies, the spider crabs look adorable. Although, it is difficult to spot these crabs because of their great camouflage.

How do they communicate?

There is no information as to how these crab species communicate among themselves.

How big is a decorator crab?

The decorator crab size is around 2 in (5 cm), which is seven times bigger than a leaf-footed bug.

How fast can a decorator crab move?

The speed of the spider decorator crab is unknown.

How much does a decorator crab weigh?

The weight of a decorator crab is unclear.

What are the male and female names of the species?

There are no specific names of spider decorator crab species.

What would you call a baby decorator crab?

The baby decorator crab is known as a baby crab or young.

What do they eat?

The spider decorator crabs are scavengers. They find their food on the reef. These decorator crabs also feed on a broad range of crustaceans, planktons, mollusks, and other benthic animals. In an aquarium, spider decorator crabs also feed on meaty foods including mussels, clams, and chopped fish.

Are they poisonous?

Yes, spider decorator crabs are sometimes poisonous. Sometimes, they stick toxic animals and plants, such as toxic seaweed, sponges, and hydroids to their body which not only provide camouflage but also a poisonous defense against predators. This process is known as Aposematism.

Would they make a good pet?

Yes, the decorator crabs are adorable and friendly pets. Humans keep them in aquariums at their homes or offices.

Did you know...

Sometimes, people get confused between corals and decorative crabs because of their same appearance.

How are they different from regular crabs?

The only difference in both of them is that the decorator crabs decorate their bodies with seaweed, rocks, algae, sponge, and many more but regular crabs do not decorate their bodies.

Can you eat a decorator crab?

Yes, decorator crab is eatable but sometimes it possesses poisonous species on their bodies. So always take care of that.

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 Sally Lightfoot crab facts and slipper lobster facts pages.

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

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