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Spindle
or False cowrie snails
Family Ovulidae
updated
Nov 11
Where
seen? These amazing snails are seen on our sea fans and
soft corals, particularly on our Northern shores.
Features: 1-3cm. These snails
have shells that resemble those of the cowries
(Family Cypraeidae) and are thus sometimes called Ovulid cowries or
False cowrise. But their shells lack strong teeth, usually elongated
and the adult snail doesn't have an operculum. Some also have long
narrow shells with pointy tips that resemble a spindle and are thus
also called Spindle cowries. Like the true cowries, ovulids also cover
the shell with their mantles. The mantle usually has the same colour
and texture as the animal that they eat. But the shell is usually
unmarked and plain white. Some also accumulate in their mantle, the
toxic chemicals from their prey.
What do they eat? Ovulids are
carnivorous and prey on sea fans, sea whips and soft corals, actually
biting off the polyps. Each species specialises in a particular prey
and they usually mimic their prey perfectly.
Ovulid babies: Ovulids lay their
eggs on their prey on the base of the host or hanging from the limbs
of branching soft corals.
Status and threats: None of our
ovulid cowries are listed among the threatened animals of Singapore.
However, like other creatures of the intertidal zone, they are affected
by human activities such as reclamation and pollution. Trampling by
careless visitors and over-collection can also have an impact on local
populations. |
The snail blends in with the sea fan!
East Coast, Jun 06
The shell opening lacks teeth,
unlike in a real cowrie.
Beting Bronok, Jul 05 |
More
spindle cowrie snails on Singapore shores
Phenacovolva nectarea
Beting Bronok, Jul 05 |
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Pellasimnia
cf. improcera
Pulau Hantu, Mar 06 |
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Phenacovolva
barbieri
Beting Bronok, May 03 |
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Family
Ovulidae recorded in Singapore
from
Wong, H. W., 2011. The Ovulidae (Mollusca: Gastropoda) of Singapore
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Spindle
cowries seen awaiting identification
Species are difficult to positively identify without
close examination.
On this website, they are grouped by external features for convenience
of display. |
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Aclyvolva
lamyi
Aclyvolva lanceolata
Calcarovula longirostrata
Calpurnus verrucosus
Carpiscula bullata
Crenavolva aureola
Crenavolva guidoi
Crenavolva leopardus
Crenavolva matsumiyai
Crenavolva matsumiyai
Crenavolva trailli
Cuspivolva formosa
Cuspivolva renovata
Cuspivolva ostheimerae
Cuspivolva queenslandica
Cuspivolva singularis
Dentiovula dorsuosa
Dentiovula rutherfordiana
Dentiovula sp.
Diminovula alabaster
Globovula sphaera
Hiatavolva depressa
Margovula marginata
Margovula pyriformis
Naviculavolva deflexa
Pellasimnia angasi
Pellasimnia improcera
Phenacovolva barbieri
Phenacovolva birostris
Phenacovolva brevirostris
Phenacovolva dancei
Phenacovolva nectarea
Phenacovolva philippinarum
Phenacovolva rosea
Primovula roseomaculata
Primovula rosewateri
Primovula cf. tropica
Prionovolva brevis
Prionovolva nivea
Prosimnia semperi
Sandalia cf. triticea
Testudovolva bullum
Volva volva |
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Links
- Family
Ovulidae on The Gladys Archerd Shell Collection at Washington
State University Tri-Cities Natural History Museum website: brief
fact sheet with photos.
- Family
Ovulidae (Egg Cowries) on the The
Seashells of New South Wales website by Des Beechey Research
Associate, Australian Museum: family introductions with photos
of shells and detailed fact sheets for many species.
- Ovulids
(False cowries) on Dr Bill Rudman's Sea Slug Forum website:
a brief intro to Onchidium with lots of emails queries and photos
and Dr Rudman's responses to them.
- Family
Ovulidae in
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.
References
- Wong, H.
W., 2011. The
Ovulidae (Mollusca: Gastropoda) of Singapore (pdf). Raffles
Museum of Biodiversity Research, National University Singapore,
Singapore. 58 pp. Uploaded 10 Nov.2011.
- 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.
- A new record
of Cymbovula segaliana Cate, 1973 (Mollusca: Gastropoda:
Ovulidae) in Singapore. H. W. Wong. Pp. 65-67. [PDF,
228 KB] on the Nature
in Singapore site of the Raffles Museum of Biodiversity Research.
- 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.
- Coleman,
Neville. 2003. 2002
Sea Shells: Catalogue of Indo-Pacific Mollusca.
Neville Coleman’s Underwater Geographic Pty Ltd, Australia.144pp.
- Kuiter, Rudie
H and Helmut Debelius. 2009. World
Atlas of Marine Fauna
. IKAN-Unterwasserachiv. 723pp.
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