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| shelled snails text index | photo index |
| Phylum Mollusca > Class Gastropoda > Family Trochidae |
| Button
snail Umbonium vestiarium Family Trochidae updated May 09 Where seen? This tiny pretty snail is found in the thousands, lying just beneath the sand surface on some parts of our Northern shores, on sand bars or sandy shores. In the past, however, they were more common on many of our mainland shores. Features: 0.8-1cm. Shell thin, smooth and circular. The shells come in an amazing variety of colours and patterns. It is said that no two button snails are alike! These snails are so enchanting that the guides call them the 'Jewels of Chek Jawa'. Thin operculum made out of a horn-like material. The animal has a long highly mobile, leaf-like foot which is used to burrow into the sand. The streamlined shell helps them burrow rapidly into wet sand. To escape predators, button snails make a short, spiralling leap then quickly bury themselves into the sand again. You might see the tiny trails left by panicky button snails, punctuated by little holes where they disappeared into the sand. When disturbed, button snails also float. The floating snails then tend to form 'rafts'. After a while, the snails will sink one by one, and burrow into the sand. Could this be a way for them to escape predatory snails and other animals that can't swim? It may also allow them to disperse to new places quickly? What does it eat? More like bivalves rather than snails, button snails filter feed for detritus and plankton. Lying buried just beneath the sand, they stick out their eyes and a tentacle above the sand to gather edible bits. Role in the ecosystem: Button snails appear to be among the favourite prey of Moon snails. Other large animals probably also snack on them. Empty buttons shells are favourite homes of tiny hermit crabs. So please resist the temptation of taking home even an empty button snail. A homeless hermit crab might need it! Human uses: Sadly, these beautiful tiny animals are collected, killed and their shells sold as cheap curios and for handicrafts. Status and threats: Button snails were highly abundant in Singapore in the 1960's, but populations have declined drastically as their habitats have since become degraded or were lost. They are now listed as 'Vulnerable' on the Red List of threatened animals of Singapore. Trampling by careless visitors and overcollection can also have an impact on local populations. |
 A big pile of living Button snails Chek Jawa, Feb 05  They can float, forming 'rafts'. Changi, Jul 08  Tiny tentacles and eyes. Changi, Jun 05 |
 Broad foot with 'tentacles' on the edges. Tanah Merah, Mar 10 |
 Closeup of shell opening and operculum. Tanah Merah, Feb 07 |
 The tiny operculum stuck to its foot. Tanah Merah, Jul 05 |
Button snails on Singapore shores
 Hermit crab (left) and living Button snail (right) Changi, Jun 05 |
 Moon snail hunting Button snails Tanah Merah, Apr 05 |
 Button snails leaping away from Moon snail Tanah Merah, Apr 05 |
 Leaf-like foot. Chek Jawa, Apr 05 |
 East Coast, Jun 06 |
 Changi, Apr 05 |
 Tanah Merah, May 09 |
 Tanah Merah, Mar 10 |
 Tanah Merah, Mar 10 |
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