The five short arms are wide at the base tapering sharply and the tip is often raised off the substrate showing the pale coloured tube feet beneath.

[2] Odontaster validus is an omnivorous scavenger and consumes anything it finds including carrion, detritus, the faeces of seals, red algae, bivalve shells, sponges, hydroids, other sea star, sea urchins, isopods, bryozoans, amphipods, crustacean larvae, ostracods, shrimps and diatoms.

[2] It is an ecologically important species because of its consumption of benthic larvae and the control it exerts on the sea star Acodontaster conspicuus and the nudibranch Doris spp.

It was found that food-deprived individual Odontaster validus could distinguish between the odours emitted by satiated and by starved sea star of the same species.

Even when not killed at higher temperatures, many organisms cease to feed, may remain immobile or fail to reproduce and others started metabolising anaerobically.

[7] A study was undertaken to examine the implications of this for the Antarctic marine environment if water temperatures rise as a result of global warming.

[7] Another research study examined the parameters required for successful fertilisation of the eggs of Odontaster validus compared to similar temperate water sea stars.