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Common Sea Urchin Heliocidaris erythrogramma


Photo of the Common Sea UrchinIts oval-shaped form is flattened above and below so that the test is only half as high as wide. The circular primary spines are long (25 mm) and taper gradually to a point. Secondary spines are not so tapered and have more blunt tips.

The test is covered with coarse tubercles. Test diameter to 90 mm.


The test may be light purple, green or creamy-white. The primary spines are purple to dark olive-green. Secondary spines are also purple or dark green. The tube feet are pale pink.




Valenciennes, 1846




Test 90 mm; Spines 25 mm


Distribution map of the Common Sea UrchinThe Common Sea Urchin ranges from Port Stephens, New South Wales around southern shores to Shark Bay and the Abrolhos in Western Australia.


Occurs under stones and overhanging ledges in pools and gutters at low tide level and below.


This is the most common sea urchin in southern Australia. This sea urchin can carve out hemispherical hollows in the rock at the lowest tide levels and below on rocky shores and in rock pools on the exposed edge of rock platforms facing the sea.


How do you think a sea urchin can carve out a home hollow in rock ?


Bennett, I. (1987) W.J. Dakin's classic study: Australian Seashores. p. 363, Angus & Robertson, Sydney

Clark, H.L. (1946) The Echinoderm Fauna of Australia: Its composition and its origin. p..329, Carnegie Institution of Washington, Publication 566, Washington D.C.

Davey, K. (1998) A Photographic Guide to Seashore Life of Australia. p.133, New Holland, Sydney.

Edgar, G.J. (1997) Australian Marine Life: the plants and animals of temperate waters. p.365, Reed Books, Kew.

Quinn, G.P., Wescott, G.C. & Synnot, R.N. (1992) Life on the Rocky Shores of South-Eastern Australia: an illustrated field guide. p.77, Victorian National Parks Association, Melbourne.

Marine Research Group of Victoria (1984) Coastal Invertebrates of Victoria: an atlas of selected species. p.148, Museum of Victoria, Melbourne.

Macpherson, J.H. & Gabriel, C.J. (1962) Marine Molluscs of Victoria. Melbourne University Press & The National Museum of Victoria.

Shepherd, S.A. & Thomas, I.M. (1982) Marine Invertebrates of Victoria, Pt. 1. p.449, South Australian Government Printer, Adelaide.

Underwood, A.J. & Chapman, M.G. (1993) Seashores: a beachcomber's guide. p.51, New South Wales University Press, Sydney.

Sea Urchins

Common Sea Urchin
Thickened Sea Urchin

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photo of Keith DaveyLife on Australian Seashores
by Keith Davey (C) 2000

Learning Consultant - Media
The University of Newcastle

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Scientific Consultant: Phil Colman
site created 01.01.98 : updated 01.04.2000