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Purple Sea Urchin / Ježinac

Paracentrotus lividus


It has a circular, flattened greenish test with a diameter of up to seven centimetres. The test is densely clothed in long and sharply pointed spines that are usually purple but are occasionally other colours including dark brown, light brown and olive green. There are five or six pairs of pores on each ambulacral plate. The tube feet are in groups of 5 or 6, arranged in small arcs


Occurs in the Mediterranean Sea and eastern Atlantic Ocean. It s is usually found just below low water mark at depths down to twenty metres and sometimes also in rock pools. It is found on rocks and boulders, and in seagrass meadows of Zostera marina and Posidonia oceanica. Although Cymodocea nodosa is a preferred food item, it is seldom found in meadows of this seagrass, perhaps because the shifting sand substrate does not suit it or because of pressure from predators. In fact it avoids soft substrates and can sometimes be found clustered on stones or shell "islands" surrounded by sand. In shallow or exposed waters it can use its mouth and spines to dig into soft rocks to create cavities into which it returns and in which it exactly fits. Where the urchins are numerous, the rock may be honeycombed by these excavations.

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Atanas Tanev
Atanas Tanev 7 years ago

Oh, poor creatures. As I say these are legends that I've read. A lot of people have the opposite experience. :)

injica 7 years ago

(btw 1st photo shows the dept in intertidal zone, it is less that 5cm so either it would die anyway or since they are always here, not cause they are used to sharp conditions)

injica 7 years ago

If you wanna save it from tourists you will pick them and throw them in deep water otherwise they will be killed ;) don't worry I am the daughter of the sea, learned to swim before I learned to walk ;)

Atanas Tanev
Atanas Tanev 7 years ago

There are legends in the reef keeping forums that sea urchins and sea stars shouldn't be picked out of the water because they swallow air which stuck into their organs, and the mortality rate was big. I don't know how true is this but to have it in mind next time. :)

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Spotted on Apr 29, 2013
Submitted on Apr 29, 2013

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