species: Thalassianthus aster in Lizard Island Field Guide (Lizard Island Field Guide)
Thalassianthus aster

©Avril Ayling: Thalassianthus sp., probably T. aster , at MacGillivray Reef near Lizard Island. Diameter is about 12 cm. Thanks to Daphne Fautin for the identification.

©Avril Ayling: Close-up of the same specimen from MacGillivray Reef.

©Barbara Banks: Thalassianthus aster on reef flat south of Bird Island, Lizard Island
Kingdom Animalia
Phylum Cnidaria
Class Hexacorallia
Order Actiniaria
Family Thalassianthidae
Genus Thalassianthus
Species Thalassianthus aster



Distinguishing features

Oral disc is not folded and does not have an undulating margin (Crowther, 2013) other than when following uneven substrate contour. Colour is highly variable and is not useful for identifying species in this group (Crowther, 2013).


  • Up to 6 cm (diameter of oral disc according to Crowther, 2013)
  • Up to 12 cm (diameter of MacGillivray Island specimen according to observer Dr Avril Ayling)


Similar taxa


Anemonefishes do not inhabit this species.

by Anne Hoggett

Rowlett (2020) calls this species Thalassianthus hemprichii and says that T. aster is much smaller.

by Anne Hoggett


Web resources


References that assist with identification

  • Crowther, A.L. (2013). Character evolution in light of phylogenetic analysis and taxonomic revision of the zooxanthellate sea anemone families Thalassianthidae and Aliciidae. PhD thesis, University of Kansas. LIRS catalog number 90289.
  • Rowlett, J. (2020). Indo-Pacific Corals. 807 pp. Joe Rowlett, Chicago, USA. ISBN: 9798686565975. LIRS catalog number 90393.