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| shelled snails text index | photo index |
| Phylum Mollusca > Class Gastropoda |
| Volutes
Family Volutidae updated Dec 08
Although some are highly prized for their large, glossy, patterned shells, living volutes are even more beautiful. Their bodies are boldly marked with colourful stripes or spots. Where seen? The Noble volute (Cymbiola nobilis) is sometimes seen on our undisturbed Northern shores. They are probably seldom seen as they are usually buried under the sand, especially during the day. The Baler shell (Melo melo) is seldom seen. Features: To about 20cm. In some, the shells are large, heavy and glossy, often with beautiful patterns. As an adaptation to burrowing in sand, seeking buried prey, the foot is large and muscular, and the siphon long, the tip sticking out of the sand while the snail is buried. What do they eat? All members of the Family Volutidae are carnivorous. Their prey include molluscs and echinoderms. A volute seeks out buried bivalves with its siphon and encloses the prey in its huge foot then waits. When the exhausted bivalve opens up to breathe (which can take several days!), the volute sticks its proboscis in and rasps the flesh of its prey with its radula. Volutes may hunt their prey from the surface, but often burrow to eat their prey under the sand. Volute babies: In members of the Famliy Volutidae, the male fertilises the female internally. There is no free-swimming larval stage and crawling juvenile snails emerge from the egg. As a result, volutes have a restricted range and local populations can be wiped out by over-collection. Noble volutes lay translucent egg capsules that contain many eggs. But only one or a few develop, the survivor having eaten the others. The eggs hatch and undergo metamorphosis within the egg capsules, emerging as tiny crawling snails. Role in the habitat: Many of the Noble volute shells contain a hermit crab instead of the living snail. Even after it dies, the snails shell continues to provide shelter! The hermit crabs need the shell more than we do so we should not collect these shells even if they are empty. Human uses: Called ‘kilah’ in Malay, the Noble volute is edible. It is also often collected for its attractive shell. The Baler shell was also eaten and its empty shell used by fishermen to scoop water out of their boats, as well as to scoop sugar, salt and flour in markets. Status and threats: The Noble volute (Cymbiola nobilis) is listed as 'Vulnerable' and Baler shell (Melo melo) as 'Endangered' on the Red List of threatened animals of Singapore due to habitat loss. The Noble volute was previously abundant in Singapore but is now considered vulnerable due to habitat degradation and overcollection for food and for its attractive shell. Like other creatures of the intertidal zone, they are affected by human activities such as reclamation and pollution. Over-collection can also have an impact on local populations. |
 Noble volute Chek Jawa, Nov 01  The shell may have different patterns and colours. Changi, Jun 06  Baler volute Beting Bronok, Aug 05  Laying her egg capsules Pulau Semakau, Mar 07 |
They are among the large snails you might see on our shores.| Family
Volutidae recorded for Singapore from Tan Siong Kiat and Henrietta P. M. Woo, 2010 Preliminary Checklist of The Molluscs of Singapore. in red are those listed among the threatened animals of Singapore from Davison, G.W. H. and P. K. L. Ng and Ho Hua Chew, 2008. The Singapore Red Data Book: Threatened plants and animals of Singapore.
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