Drupella cornus

Drupella cornus (Röding, 1798) is a carnivorous marine snail in the genus Drupella. Snails in this genus feed exclusively on corals, and prefer those in the family Acroporidae: table, elkhorn or staghorn corals.

Sometimes they aggregate in large numbers - a phenomenon linked to significant coral death.

Since the early 1980s, outbreaks of Drupella snails have been reported in Ningaloo Reef in western Australia, Izu Islands in southern Japan, and in Eliat and the Gulf of Aqaba in the northern Red Sea.

In one outbreak on the Ningaloo Reef, coral cover was reduced up to 85 per cent. At the time, the detrimental effects of Drupella snails was compared to those of the notorious crown of thorns starfish.

However, unlike the starfish, Drupella snails are not immune to the stinging cells - nematocysts - of live coral. They avoid contact with live coral tissue, preferring to perch on dead coral and feed on the live tissue by extending a proboscis.

This means that corals that have been previously damaged by other predators, severe storms or climate change are more prone to predation by Drupella snails.

However, scientists believe that predation by Drupella is not a major threat to corals, compared to other threats such as over-fishing, habitat destruction, and costal run-off.

Species detail

Coral feeding is an unusual adaptation in molluscs - the only other obligate coral feeders in the Muricidae are the coralliophilids, which parasitise corals from inside and out.

Distribution

The snail is found on corals in the Indo-West Pacific. During population explosions there can be as many as 175 snails per square metre of coral. Discover how the snail exploits its coral base as a food source.
Biology

The snail’s eggs hatch into free-swimming larvae. Find out more.
References

Get reference material for Drupella cornus.