The Velvet Swimming Crab, also known as Devil Crab, Lady Crab or simply Velvet Crab, is a species in the order of Decapoda and thus belongs to the subphylum of crustaceans. Necora puber was first described by Linnaeus in 1767.
Description, Features & Anatomy
The velvet crab has a flat body with red, orange, green and beige tones. It is possible that the colouring varies. However, the tips of the scissors are always black. In addition, the back of the body is completely overgrown with velvety hair.
As it belongs to the decapoda Necora puber has five pairs of limbs. The front one is converted into scissor hands, which are large in comparison to the body. In addition, they are conspicuously pointed and studded with many small wart-like nodules. Three of the pairs of links serve as feet for locomotion and the rearmost pair of links consists of lined up plates. These are used by the crab to swim quickly.
The velvet crab reaches a diameter of up to 10cm.
Habitat & Distribution
Necora puder lives on rocky or stony ground, in depths down to 80m. It prefers places with hiding places, such as small caves or rocky outcrops.
When scuba diving on the Canary Islands you can rarely see the Velvet Swimming Crab. I’ve seen it on night dives only so far. However, it is very shy and quickly runs off the light.
In general, their distribution range extends from southern Norway to Western Sahara and across the Mediterranean Sea and the Black Sea. It can also be found around Great Britain, in the North Sea, on the Azores, Madeira, Morocco and the European Atlantic coast.
Biology, Feeding & Reproduction
The Velvet Swimming Crab is a predator and feeds on other small crustaceans, mussels, brown seaweed and sea urchins.
Necora puber can move very quickly due to its deformed rear pair of limbs.
It is also said to be an aggressive species, so be careful with macro shots!
Actually, it is rather nocturnal, but you can also observe it sometimes during the day.
Depending on the region, Necora puber reaches sexual majority at an age between 1 and 1.5 years with a size of 4 to 5 cm. Mating occurs when the female has shed its skin. In Scotland the females carried between 5000 and 278000 eggs. In addition, it is assumed that the females spawn several times a year. They have the ability to carry the sperm of the males under their shell for a longer period of time.
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