species: Heterocentrotus mammillatus in Lizard Island area: all known taxa (Lizard Island Field Guide)
Heterocentrotus mammillatus

©Lyle Vail and Anne Hoggett: Heterocentrotus mammillatus at night near Research Station
Kingdom Animalia
Phylum Echinodermata
Class Echinoidea
Order Echinoida
Family Echinometridae
Genus Heterocentrotus
Species Heterocentrotus mammillatus



Distinguishing features

Commonly known as the slate-pencil urchin, Heterocentrotus mammillatus is unmistakeable. It has a slightly oval test, the longest dimension of which can be 100 mm or more. The spines are thick and solid, rounded to triangular in cross section with flattened tips.


  • Size data has not been obtained.

Depth range

  • Depth range data is not yet available.



©Atlas of Living Australia: Australian distribution

Distribution and habitat preferences

This species is not common at Lizard Island and it is not represented from that locality in the Australian Museum collections. Its record is based on rare observations of the species, always at night.

Web resources


References that assist with identification

  • Clark, A.M. and F.W.E. Rowe (1971). Monograph of shallow-water Indo-west Pacific echinoderms British Museum (Natural History), London.

Other references

  • Young, M.A.L. and D.R. Bellwood (2011). Diel patterns in sea urchin activity and predation on sea urchins on the Great Barrier Reef. Coral Reefs, 30: 729-736. LIRS catalog number 1483.