seen? These strange snails are almost always found on large
shells inhabitated by hermit crabs. They are also seen on the undersides
of large living horseshoe crabs.
What are slippers snails? Slipper
snails are NOT bivalves (like oysters).
They are gastropods that belong
to the Family Crepidulidae.
Features: 2-3cm. Shell conical
or flat domed. Several may be found stuck firmly onto inside of a
shell occupied by a hermit
crab. They take advantage of the constant current of freshly oxygenated
water that the hermit crab creates for itself. They are also found
on the underside of living horseshoe
Sometimes confused with limpets which are also gastropods but which can move about. Here's more on how to tell apart limpets,
slipper snails and similar animals.
What do they eat? Slipper snails
filter feed and possibly also gather the leftovers of the hermit crab's
Slipper snail babies: Slipper
snails can change gender. They are usually found in pairs. The larger
one is the female and the smaller one male. When the smaller one grows
big enough, it will change into a female! The females produce flask-shaped
capsules with several eggs in one capsule. The capsules are brooded
in the mantle cavity.
Two different kinds of slipper snails on this shell occupied by a hermit crab.
Changi, Apr 05
smaller shell is usually the male.
Chek Jawa, Mar 05
snails on Singapore shores
Calyptraeidae recorded for Singapore
Tan Siong Kiat and Henrietta P. M. Woo, 2010 Preliminary Checklist
of The Molluscs of Singapore.
- Tan Siong
Kiat and Henrietta P. M. Woo, 2010 Preliminary
Checklist of The Molluscs of Singapore (pdf), Raffles
Museum of Biodiversity Research, National University of Singapore.
- Tan, K. S.
& L. M. Chou, 2000. A
Guide to the Common Seashells of Singapore. Singapore
Science Centre. 160 pp.
- Wee Y.C.
and Peter K. L. Ng. 1994. A First Look at Biodiversity in Singapore.
National Council on the Environment. 163pp.
- Ng, P. K.
L. & Y. C. Wee, 1994. The
Singapore Red Data Book: Threatened Plants and Animals of Singapore.
The Nature Society (Singapore), Singapore. 343 pp.