Paracentrotus lividus is a species of sea urchin in the family Parechinidae, commonly known as the purple sea urchin.
This echinoderm serves as the type species for its genus and inhabits rocky substrates across the Mediterranean Sea and eastern Atlantic Ocean. Like other sea urchins, it grazes on algae and organic matter, its characteristic purple test and spines making it distinctive among coastal invertebrates. The species plays an ecological role in marine ecosystems by controlling algal growth, though intensive harvesting for its edible roe has placed pressure on populations in certain regions. Its presence indicates healthy rocky shore habitats where sufficient food sources and suitable substrate allow it to maintain stable populations.
