learn only 3 things about them ...
are almost certain to see these large snails during a
visit to our mangroves.
are edible and were eaten in the past, less so these days.
Most are harmless herbivores, nibbling on algae.
Horn snails are common in our mangroves but often overlooked. Some
are tiny. Others like the Rodong, are large.
Features: Shell long and conical.
The operculum is made of a horn-like material usually with a tight
spiral pattern. The Chut-chut (Cerithidea
obtusa), Belitong (Terebralia sulcata)
and Rodong (Telescopium telescopium)
have a third eye on their mantle margin, in addition to a pair of
eyes on tentacles. Here's
more on how to tell these snails apart.
Sometimes confused with Creeper
snails (Family Cerithiidae) which also have an operculum made
of a horny material but with only a few whorls. Horn snails have siphonal
canals that are less pronounced and they are generally larger than
Creeper snails. More on how to tell
these snails apart.
What do they eat? Horn snails
graze on detritus and algae growing on the bottom or other surfaces
such as tree trunks. Many feed at low tide, some in very large groups.
Horn snail babies: Members of
this family have separate genders. The male transfers a sperm packet
into the female. Eggs are laid in a gelatinuous mass on hard surfaces
or the muddy bottom.
Human uses: Many Horn snails are
eaten by people. Rodong (Telescopium
telescopium) is said to be delicious when steamed and eaten with
chilli. Chut-chut (Cerithidea obtusa)
is boiled and eaten by biting off the tip and sucking out the animal.
Even the small Belitong (Terebralia sulcata)
is also said to taste good.
Sungei Buloh Wetland Reserve, Mar 06
The Red Chut-chut snail (above) and
the Black Chut-chut snail.
Pasir Ris, Jun 10
Operculum with tight spiral.
Kranji, Jan 10
snails on Singapore shores
Potamididae recorded for Singapore
from Tan Siong
Kiat and Henrietta P. M. Woo, 2010 Preliminary Checklist of The
Molluscs of Singapore.
creepers (Cerithidea obtusa), Belitong
(Terebralia sulcata), Rodong/Berongan
(Telescopium telescopium) Ng, Peter K. L. & N. Sivasothi,
1999. A Guide
to the Mangroves of Singapore II (Animal Diversity). Singapore
Science Centre. 168 pp.
Creeper Shell (Telescopium telescopium), Obtuse creeper
(Cerithidae obtusa), Sulcate creeper (Terebralia sulcata)
Shell (Batillaria zonalis) Tan, Leo W. H. & Ng, Peter
K. L., 1988. A
Guide to Seashore Life. The Singapore Science Centre,
Singapore. 160 pp.
Potamididae on The Gladys Archerd Shell Collection at Washington
State University Tri-Cities Natural History Museum website: brief
fact sheet on Nerites with photos.
- Family Potamididae
the Gastropods section by J.M. Poutiers in the FAO Species Identification
Guide for Fishery Purposes: The Living Marine Resources of the
Western Central Pacific Volume
1: Seaweeds, corals, bivalves and gastropods on the Food and
Agriculture Organization of the United Nations (FAO) website.
- 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.
- Abbott, R.
Tucker, 1991. Seashells
of South East Asia.
Graham Brash, Singapore. 145 pp.