Heliocidaris sp. Click to enlarge image
Purple Sea Urchin, Heliocidaris sp. Image: Dr Isobel Bennett
© Australian Museum

Fast Facts

  • Classification
    Species
    erythrogramma
    Genus
    Heliocidaris
    Family
    Echinometridae
    Order
    Echinoida
    Class
    Echinoidea
    Phylum
    Echinodermata
    Kingdom
    Animalia
  • Size Range
    11 cm

Introduction

The Purple Sea Urchin is one of the most common sea urchins found on Sydney's coast.

Identification

Colours can vary so dramatically in this species, from light olive green to pink to a dark purple, that the Purple Sea Urchin was once thought to be three separate species.

Habitat

Purple Sea Urchins live on intertidal rocky shores and in coastal waters to a depth of 35 m.

Distribution

Purple Sea Urchins are found in southern Queensland, New South Wales, Victoria, South Australia and Western Australia.

Other behaviours and adaptations

In order to gain protection from predators and the elements, Purple Sea Urchins cluster together and use their sharp spines to burrow into the rock. They are often seen with parts of shells and sand covering its test (body).

Economic impacts

This species is sometimes collected for food. In Sydney there are bag limits, and certain rock platforms have been designated Aquatic Reserves where collecting is not permitted.