Download The Seashells

The Seashore Life of the Brunei Heart of Borneo
Volume 3:
The Seashells
by
Roger McIlroy
and
Novi E. Yusniasita Dols
including
Fossil Shells by Han Raven
Photographs
by
Roger McIlroy (RM)
Novi E.Yusniasita Dols (NY)
Hans Dols (HD)
Claudia and Walter Obendrauf (CO)
1st Edition: Nov 2008
Panaga Natural History Society
Panaga, Seria, Brunei Darussalam
1
1) Tun 2) Fig Shell 3) Moon Snails 4) Apple Snail 5) Helmet Shell 6) Tibia 7) Turritella 8) Straw Sundial
(left) and Clear Sundial (right) 9) Cone Shell 10) Conch (fossil) 11) Helmet Shell 12) Top Shells (Moon Snail
to upper left) 13) Common Button Tops 14) Olives 15) Helmet Shells 16) Babylon 17) Frog Shell 18) Clam
19) Nerite 20) Cowrie 21) Egg Cowrie 22) Murex 23) Ark Shell 24) Murex 25) Rays Shell 26) Cockles 27)
Donax Clams 28) Donax Clams 29) Oyster 30) Giant Barnacle 31) Egg Case 32) Sand Dollar 33) Starfish
This display of shells collected by Claudia Obendrauf offer a very fine selection of the
commonest shells to be found on the Heart of Borneo Beaches (CO)
Published by
Brunei Press Commercial Printing Services
Email: [email protected]
Website: www.bruneipress.com.bn
Tel: +673 245 6170
1st Edition published in Nov 2008
ISBN 99917-32-23-3
Copyright © 2008 in text: Roger McIlroy and Novi E. Yusniasita Dols
Copyright © 2008 in photographs: Roger McIlroy and Novi E. Yusniasita Dols or as credited
All rights reserved. No part of this publication may be reproduced, stored in a retrieval system, or transmitted,
in any form or by any means, electronic, mechanical, photocopying, recording or otherwise, without the prior
written permission of the copyright holders.
Contact the authors and find out more about this series via:
PNHS website: http://www.bsp.com.bn/panagaclub/pnhs/
Cover Photograph: The tiny Common Button Tops Umbonium vestiarum are as common and as beautifully
variable on the beach as snowflakes in a blizzard. Every one has a unique coloration and pattern, and offer
fantastic photos for the close-up cameraman. A Nassa Mud Snail Nassarius (Zeuxis) castus, with hermit crab and a
brown Whelk Cantharus (Clivipollia) wagneri have gate crashed this Common Button Top assemblage. (RM)
Printed in Brunei Darussalam
Contents
Section 1:
The Seashells........................................................................ 1
Gastropods........................................................................... 4
Abalones...................................................................................... 6
Babylons...................................................................................... 7
Conches (Kalasiu or Gong-gong)................................................. 8
Cone Shell................................................................................... 9
Cowrie......................................................................................... 10
Crown Shell................................................................................. 11
Ear Shell....................................................................................... 11
Fig Shells...................................................................................... 12
Frog Shell..................................................................................... 13
Harp Shell.................................................................................... 13
Helmet Shells............................................................................... 14
Horn Shells.................................................................................. 15
Limpets........................................................................................ 16
Mitres.......................................................................................... 18
Moon Snails................................................................................. 19
Mud Creepers (Tekuyong Sirok).................................................. 21
Murex.......................................................................................... 22
Nassa Mud Snail.......................................................................... 23
Nerites (Tekuyong Timba)........................................................... 24
Olives........................................................................................... 25
Sundials....................................................................................... 28
Tibias........................................................................................... 29
Triton Shells................................................................................. 30
Tankard Shells.............................................................................. 31
Top Shells.................................................................................... 31
Tuns............................................................................................. 33
Turban Shell................................................................................. 34
Turritella...................................................................................... 35
Vase Shell..................................................................................... 36
Volutes......................................................................................... 36
Wentletrap................................................................................... 37
Readers who wish to search by the scientific name are referred to the Index
and Checklist at the back of the booklet.
Section 2:
Bivalves................................................................................ 38
Ark Shells..................................................................................... 41
Asiatic Hard Clams...................................................................... 42
Cockles........................................................................................ 42
Donax Clams............................................................................... 43
Glass Shells.................................................................................. 44
Oysters (Tiram)............................................................................ 46
Piddocks...................................................................................... 47
Razor Shell or Razor Clam (Pahat-pahat)..................................... 48
Ray Shells..................................................................................... 49
Shipworms................................................................................... 50
Terrestrial and Fresh Water Snails......................................... 51
Apple Snails (Kalambuai)............................................................. 51
Land Snail.................................................................................... 52
Cephalopods........................................................................ 53
Harvest Cuttlefish (Kalabutan)..................................................... 53
Echinoderms........................................................................ 54
Keyhole Sand Dollar..................................................................... 55
Sand Star...................................................................................... 56
Coelenterata......................................................................... 57
Coral............................................................................................ 57
Crustaceans.......................................................................... 58
Crabs........................................................................................... 59
Fossil Shells (by Han Raven)................................................ 60
Displaying Shells.................................................................. 64
Photographic Notes.............................................................. 66
Glossary................................................................................ 67
References............................................................................ 70
Websites............................................................................... 71
Checklist and Index to Species............................................. 72
Quick identification Guides for Common Gastropods......... 76
Foreword
Dr Grahaeme Henderson
Managing Director,
Brunei Shell Petroleum
C
are and concern for the environment is an integral part of Brunei Shell
Petroleum (BSP)’s business. Our efforts were duly recognised in 2008
when we won the prestigious Shell Chief Executive HSSE global award for
environmental performance. Everyone in Brunei Darussalam is proud of
this huge achievement.
BSP is the leader in the private sector in providing support for the
Government’s conservation efforts. We contribute significantly towards
the Government-led, landmark biodiversity conservation initiative, the
Heart of Borneo. We also partner the Government on a wide range of
initiatives, including the Anduki forest reserve biodiversity plan, Sungai
Seria wetlands, PRYNSA schools’ outreach programme, and numerous eco
tourism projects.
BSP is delighted to sponsor this series of booklets on the seashore life of
Brunei Darussalam written by our employees, along with contributors
from Panaga Natural History Society and others passionate about the
environment. Well researched and attractively illustrated, they will further
add to efforts to promote this country’s incredibly rich, hugely diverse and
largely pristine environment to a wider audience.
Looking after our environment is vital…for today, tomorrow and for future
generations.
Preface
Hans Dols
Honorary President,
Panaga Natural History Society
(PNHS)
M
any who visit Brunei’s tropical seashore will be quickly aware they
are entering a very special place. This is a new world with much to
be seen, touched and explored. All will be fascinated by the diversity of our
coastal ecosystem and want to find out why it is so important to them and
to Brunei.
What started as short leaflets to illustrate our beach excursions has grown
into a series of booklets presenting a whole gamut of information dealing
with our coastal flora, fauna, and the physical environment we all share.
Roger McIlroy compiled the information from various sources and with
the help of contributors from the PNHS and others involved in preserving
Brunei’s environment has spent many hours distilling the best information
on a multitude of topics and has managed to write all this down in a very
handy and readable format fit for a wide audience.
This series of booklets are only a start and the PNHS hopes that many
will be inspired by this work to create further editions on the seashore life
and indeed on other wildlife of Brunei to help sustain these wonders for
posterity.
Acknowledgements
T
he seashell collections on which this guide is based are mostly from
Panaga beach, between Kuala Belait and Seria. Many of the specimens
can be inspected in the PNHS shell collection, in which regard we would
like to acknowledge Ricardo Villar who from 1992-1995 recorded more
than 200 gastropod species and donated his collection to the PNHS, and
also Kwie Hiang van de Graaf for making available her extensive collection
of Panaga beach seashells for study.
In particular we should thank Dr Han Raven who collected more than
2000 species of recent and fossil shells from Sarawak, Brunei and Sabah
while residing in Miri, Sarawak, from 1992-1997. Han is now a scientific
associate with the National Natuurhistorisch Museum, Naturalis in the
Netherlands, and based on his collection is preparing a series of “Notes
on Molluscs from North West Borneo” for “Vita Malacologica.” With his
encyclopaedic knowledge of Borneo shells, he has been invaluable in the
correct identification of the PNHS shell collection, the shell collection in
the Brunei Muzium and in the editing of this booklet.
We would also like to thank Marina Wong, Aziah binte Hj Ahmad and
Esther Lee for their inspirational 1996 Common Seashore Life of Brunei,
an indispensible reference, Jackie Maskall for her editorial skills, the BSP
External Affairs Dept. Team and May Lim and the Brunei Press Team for
the final product.
The Heart of
Borneo Initiative
T
he World Wildlife Fund (WWF)
has for many years been driving
initiatives to protect the biodiversity
of the Borneo rainforest. In addition,
efforts to promote responsible forest
trade have reached new milestones.
In November 2003, the WWF
brought to Singapore groups such
as Conservation International (CI),
Wildlife Conservation Society (WCS)
and The Nature Conservancy (TNC);
where it was agreed that the concept
of a transboundary conservation
area in Borneo should be promoted,
with WWF taking the lead. This area
became known as the Heart of Borneo,
and this programme is leading the way
to conserve one of the world’s most
precious biodiversity treasures (Ref
1). The support of the three nations
that make up the island of Borneo,
Brunei, Indonesia and Malaysia, was
Brunei on NW Coast of Borneo (Ref 10)
secured, culminating in the
Declaration on The Heart of
Borneo Initiative signed in
Bali, Indonesia, in February
2007.
The Heart of Borneo,
with its message of:
“Three Countries, One
Conservation Vision” covers
a total of 220,000 square
km of equatorial rainforest
The signatories of the Declaration on the Heart of Borneo through a network of
Initiative: Three Countries, One Conservation Vision.
areas
and
Brunei’s signatory, Pehin Dato Dr. Awang Haji Ahmad bin protected
Haji Jumat, on far left (Brunei Forestry Dept)
sustainably-managed forest,
and through international
co-operation led by the governments of the three countries.
The approximate boundaries of the HoB rainforest with the preliminary demarcation of the HoB
rainforest
Brunei has the highest proportion of its land area covered by rainforest and
is unique and special in that the Heart of Borneo rainforest continues into
the lowlands. This means the HoB rainforest is never far from the coast
throughout Brunei, and actually reaches the seashore of the South China
Sea in the Belait District near Kuala Belait, and Brunei Bay in Temburong.
This the third volume in this series describes the seashells and other shelly
remains to be found on this seashore and follows on from the volumes
describing the physical environment and the seashore plants.
The Seashells booklet also covers many other “finds” washed up or stranded on the beach. The
Starfish Astrospecten sp. is one example. Heart of Borneo beaches have many of these voracious
hunters, who embrace their prey then extrude their stomach out to engulf and ingest it! (RM)
The Seashells
The Seashells
Introduction
T
he HoB beaches provide a rich and fascinating source of seashells. A
casual walker can always rely on finding a wide variety of shells, and at
low tide, the living shellfish can be examined. Each visit is almost guaranteed
to provide something new and fascinating.
The Heart of Borneo beaches, nature coexisting with Brunei’s hydrocarbon development (BSP)
1
The Seashore Life
of the Brunei Heart of Borneo
Seashells are the hard outer protective case of marine organisms collectively
called shellfish. Of these, the molluscs are the largest group. Molluscs have
adapted, survived and diversified far longer and far more successfully than
most groups of organisms. Unlike most organisms, molluscs, especially
shelled molluscs, have chronicled these progressive changes in a 570 million
year long fossil record. Shells stand therefore as examples of the cumulative
refinements of form resulting from natural selection over hundreds of
millions of generations. That evolution produces such forms of beauty and
also produces creatures (us!) that can appreciate such beauty is a matter of
wonderment.
Molluscs (Kerang-kerang in Malay) provide a fairly wide range of seashells.
The number of species living along the Brunei coast is likely to be many
hundreds, if not several thousand, (Ref 9) though only a small proportion can
A typical sifting of shells from the beach at low tide (RM)
2
The Seashells
be considered common
as the HoB beaches
offer no sheltering
rocks or coral. The
broad stretch of fine
sand is very exposed
to the elements with
strong tides and wave
action, meaning that
though
occasionally
washed up, algae and
seaweeds do not grow Clam fisherlady equipped for a good catch of Kanau (RM)
there. There is therefore
a limited choice of habitats and food for shellfish. However a wide range
of relatively uncommon shells are also washed up from deeper water further
offshore and also fossil shells from older sediments which are eroded away
are often found.
The living molluscs that can be routinely observed are generally small
although abundant, like the Common Button Top, the Donax Clam and
Common Olive. A number of large edible bivalves are present and although
not readily visible can be examined as captives in fishermen’s buckets.
There are eleven or so classes of organisms in the Mollusc phylum (a phylum
is a group of animals with a similar body plan), of these the main classes
described in this volume are the gastropods, bivalves and cephalopods. The
Bold script refers to the common name in English, and also in bold, but in
brackets, the local Malay name followed by the Family name. On the next
line, the scientific name is given in italics followed by the author citation,
ie the name of the individual (or team) who first described the species, the
year, and the length of the shell in mm.
3
The Seashore Life
of the Brunei Heart of Borneo
Gastropods
G
astropods are the most diversified class in the phylum of molluscs, with
60,000-75,000 known living species. This class of animals is second
only to insects in its number of known species. Gastropods have a single spiral
shell formed from calcium carbonate secreted from the mantle, the outside
of the body wall of the mollusc. The animal inside has a head with eyes and
tentacles and a mouth equipped with an abrasive tongue or “radula” with
which it can graze on diatoms and other algae or in some species, penetrate
the shells of its prey. The radula is covered in sharp teeth in rows with as
many as 1000,000 teeth. The radula also acts like a conveyor belt, bringing
forward new teeth as old teeth are worn away. Predatory marine snails
such as the Cone Shells use a specialized radula tooth as a harpoon. Many
gastropods can retreat into their shell and close a door (operculum) behind
them to avoid predation, although in others, the operculum is reduced
or eliminated, or even adapted for other uses. For instance, in species of
conches, the operculum is elongated and claw-shaped, and is used to dig into
the sand to enable
the conch to perform
a leaping type of
locomotion. Many
marine gastropods
are
burrowers,
and have a siphon
acting as a snorkel,
enabling the animal
to continuously draw
in a water current
Main organs of a marine gastropod, drawn and annotated by Novi
containing oxygen Dols
4
The Seashells
and food into their bodies. The siphon
is actually an elongated extension of
the mantle which is rolled into a tube.
The snail extends it out of the left side
of its shell to suck in water, which then
flows past the gill “ctenidium” to take in
oxygen, and exhale carbon dioxide, the
oxygen depleted water being expelled
at the right side.
The siphons are also used to “taste”
the water, in order to detect prey from
a distance. Sometimes the shell has a
siphonal canal to accommodate and
protect this structure. Gastropods
also have a single muscular foot that
has evolved to allow movement and
tunnelling.
Operation of the gastropod radula. Tongue
muscles (brown) move the abrasive radula,
which is a toothed chitinous ribbon, back and
forward to scrape food or bore into a victims
shell (Ref W13)
A.
1.
2.
9.
D.
F.
3.
C.
E.
4.
6.
10.
5.
7.
8.
B.
G.
A. Apex posterior
B. Anterior
C. Length
D. Spine
E. Body
F. Whorl
G. Aperture
1. Shoulder
2. Axial ribs
3. Spiral ribs
4. Labial ribs
5. External Lip
6. Internal Lip
7. Siphon
8. Siphonal canal
9. Situres
10. Columellar folds
Schematic of a gastropod shell, drawn and annotated by Novi Dols.
5
The Seashore Life
of the Brunei Heart of Borneo
Abalones Fam. Haliotidae
Ear Abalone Haliotis planata Sowerby, 1833, 57 mm
I
t is unfortunately
rare to find this
large and beautiful
shell locally. The
shell is thin and
light, but not fragile,
and is characterised
by a line of holes
on the side known
as “ostioles” which
allow the release
Ear Abalone Haliotis planata (NY)
of water from the
gills. The innermost
layer of the shell
is composed of
mother-of-pearl,
which in many
species is highly
iridescent, giving rise
to a range of strong
and
changeable
colours which make
Ear Abalone Haliotis planata underside showing iridescent
them attractive as
mother-of pearl (NY)
decorations.
The
flesh of certain large abalones is a desirable food. Abalones live in shallow
water beneath rocks along the shoreline and in reef plateaux. They are
herbivorous, feeding on algae.
6
The Seashells
Babylons Fam. Babyloniidae
Spotted Babylon Babylonia borneensis Sowerby III, 1864, 30-50mm
The Babylon Babylonia borneensis, one of the most beautiful of Panaga gastropods but common only
in fragments. (30-50mm) (RM)
I
t is difficult to find a perfectly
intact Babylon although many
fragments of broken Babylon
shells can be found, quite easy
to recognize because of their
distinctive pattern. The base
colour is cream with brown spots
in spiral rows. In older specimens
the brown spots fade to orange.
The operculum is horny.
The Babylon Babylonia borneensis. The shell in the
middle is fresh, whilst the outer two are older and
discoloured. (HD)
Babylons are primarily scavengers, feeding on carrion. In some parts of SE
Asia, they are caught for food in bamboo traps baited with dead fish.
7
The Seashore Life
of the Brunei Heart of Borneo
Conches (Kalasiu or Gong-Gong) Fam. Strombidiae
Aratrum Conch Strombus (Euprotomus) aratrum Roding, 1798, 80 mm. (locally as fossils)
Dog Conch (Kalasiu) Strombus (Laevistrombus) canarium Linnaeus, 1758, 67 mm. and the
closely related Strombus (Laevistrombus) turturella Röding, 1798
Marginate Conch Strombus (Dolomena) marginatus robustus Linnaeus, 1758, 48 mm.
Vittate Conch Strombus (Doxander) vittatus apicatus Man in’t Veld & Visser, 1993 60 mm.
Dog Conch Strombus (Laevistrombus) Aratrum conch Strombus
turturella (NY)
aratrum (NY) (probably
a fossil).
C
onches are edible herbivorous gastropods
Vittate Conch Strombus vittatus
of a medium to large size (50-160mm)
apicatus (HD)
that inhabit sandy mud in shallow water. As
they graze the sea bottom on algae and other
vegetable matter, the flared shell edge protects the animal while feeding.
They are sometimes called the sea cows of the shell world! They also have a
strong foot that, aided by a serrated operculum, allows them to vault away
from predators.
At least four types of conch as listed above can be found locally, the Dog
Conch being the most common. This is handy, as it is a prized dish, and
can be widely found deep fried (often as fritters) in SE Asia.
The Aratrum Conch found locally is probably a fossil as fresh specimens
have only been reported from Sabah (Ref 9).
8
The Seashells
Cone Shell Fam. Terebridae
Figuline Cone Conus (Cleobula) figulinus Linnaeus, 1758, 55 mm.
Hyaena Cone Conus (Chelyconus) hyaena Hwass in Bruguiere, 1792, 54 mm.
Textile Cone Conus (Cylinder) textile Linnaeus, 1758, 78 mm.
S
everal types of Cone Shell are
found on the HoB beaches,
although identification is not
easy as the shell is sometimes
covered with a horny skin
(periostracum), which conceals
the pattern.
Also, beware!
They have From left to right a.b. Conus hyaena, c.d. Conus
figulinus Only the one on the right is fresh, the others
an elongated proboscis that are probably Holocene fossils (Ref 9) (RM)
contains tiny harpoon shaped
structures that are actually modified teeth. Contact with prey will trigger
the harpoon, carrying along with it enough venom to paralyse the victim or
worse – live individuals should not be handled! (Ref 6).
Thankfully, only the shells are usually found here, although live Figuline
Cones with their black body and shells covered by algae have been seen in a
tide pool at Panaga E7. Thankfully this species is harmless (Ref 9).
The most dangerous cone shell, the textile shell, Conus (Cylinder) textile
(Linnaeus, 1758) 78 mm, is found locally but only so far as empty specimens
or fragments in Panaga, Muara, and Miri, Sarawak.
Live Conus (NY)
Textile Cone Shell Conus (Cylinder) textile (NY)
9
The Seashore Life
of the Brunei Heart of Borneo
Cowrie Fam. Cypraeidae
Arabian Cowrie Cypraea arabica Linnaeus, 1758, 47 mm.
Miliaris Cowrie Cypraea miliaris Gmelin, 1791
Onyx Cowrie Cypraea onyx Linnaeus, 1758
C
ommon cowries found in Panaga are small
but beautifully formed. Fresh specimens are
glossy with vivid colours, but most specimens
found on the beach are old and worn
Like most snails, cowries begin life with a typical
helically coiled shell. The final whorl however
becomes greatly expanded and envelops all
previous whorls.
Cowries look very different in action, as the
shell is completely enveloped by the mantle
(outer layer of the body) which also maintains
the glossy surface of the shell by the secretion
of a pearl-like substance. Juvenile cowries are
often plain and only develop complex patterns
and colours in adulthood.
Arabian Cowrie Cypraea arabica
(NY)
Arabian Cowrie Cypraea arabica
underside (NY)
Top: Cypraea arabica, lower left: Cypraea miliaris, lower right: Cypraea onyx (5 cent piece) (RM)
10
The Seashells
Crown Shell Fam. Melongenidae
Crown Shell Hemifusus ternatanus Gmelin, 1791, 120 mm.
T
his carnivorous animal feeds on
other molluscs on muddy bottoms
near mangroves or estuaries. It is a rare
shell locally, coveted because of the large
and unique aperture. Bright brown in
colour, it has a long siphonal canal and
a thick, elongated operculum.
Crown Shell Hemifusus ternatanus (NY)
Ear Shell Fam. Ellobiidae
Midas Ear Shell Ellobium aurismidae Linnaeus, 1758, 82 mm.
Nuclea Ear Shell Cassidula nucleus Gmelin, 1791, 22 mm.
Panther Ear Shell Pythia pantherina A. Adams, 1850, 16 mm.
Panther Ear Shell showing lateral stripes (RM)
T
his family has relatively few species
and is limited to habitats of
intertidal mangrove or brackish water
swamp in the Heart of Borneo sungais.
They are terrestrial snails and breathe air
through lungs. The name “ear” derives
from the very prominent enlarged teeth
on the lip, which prevent predators
entering the aperture to attack the Ear
Panther Ear Shell Pythia pantherina (NY)
11
The Seashore Life
of the Brunei Heart of Borneo
Shell. Panther Ear Shells also have a “stripe” along the side. The Midas Ear
Shell E. aurismidae is much broader and when alive, is covered by a thin,
dark brown periostracum. In the photograph, the periostracum has been
eroded revealing the shell’s white colour beneath.
Nuclea Ear Shell Cassidula nucleus (NY)
Midas Ear Shell Ellobium aurismidae (NY)
Fig Shells Fam. Ficidae
Variegated Fig Shell Ficus variegata Roding, 1798, 47 mm.
Underlined Fig Shell Ficus subintermedia d’Orbigny, 1852, 50 mm
(almost certainly a junior synonym of Ficus ficus Linnaeus, 1758, (Ref 9)
T
Variegated Fig Shell Ficus variegata
distinguished by purple aperture
(RM)
Fig shells Ficus subintermedia. wide
opening indicative of predatory
burrowing (RM)
12
hese predatory snails get their name from
their shape, which is reminiscent of the
fruit, and live on sandy bottoms at tide levels
and below, generally at depths exceeding
25 metres where they feed on worms and
echinoderms such as sand dollars. The
attractive light and fragile shell is tinted orange
with brown tints with varying numbers and
sizes of spots. The streamlined and large open
aperture is indicative of a predatory burrowing
habit.
The Seashells
Frog Shell Fam. Bursidae
Elegant Frog Shell Bufonaria elegans Sowerby, 1835, 42 mm.
Rana Frog Shell Bufonaria rana Linnaeus, 1758, 36 mm.
T
he common name Frog Shell comes from the knobbly sculptured
aspect of most species, which resembles the warty skin of some frogs.
These species live on sandy bottoms below tide level. They are carnivorous
and secrete an acid used to paralyse their prey of various worms. Sized up
to 50mm, the shells are fairly common on the beach as homes for hermit
crabs.
Rana Frog Shell Bufonaria rana (RM)
Elegant Frog Shell Bufonaria elegans with resident
hermit crab (HD)
Harp Shell Fam. Harpidae
Harpa articularis Lamarck, 1822, 35 – 60 mm.
H
arps are relatively large predatory
molluscs that live buried beneath
the sand in shallow water. They are
characterised by strong radial ribbing that
adds strength to the shell. They are able
to shed the rear portion of their foot, like
the ability of some lizards to shed their
tails, this presumably distracts potential
predators while the animal escapes.
Harp Shells: Harpidae Harpa articularis
(RM), specimen on the right worn by
wave action.
It is reported that Harp Shells come to
the surface after dark to forage, mainly for crabs.
13
The Seashore Life
of the Brunei Heart of Borneo
Helmet Shells Fam. Cassidae
Helmet Shell Phalium bisulcatum Linnaeus, 1758, 64 mm.
Helmet Shell Phalium (Phalium) bandatum Perry 1811
H
elmet shells
(so
called
as large varieties
can be the size
and shape of an
old
fashioned
military helmet),
are
relatively
common
and
have a distinctive
grid-like pattern.
Broken parts are
usually
found,
but an occasional
Helmet Shell Phalium bisulcatum (Ref W12)
complete specimen
turns up. Helmet Shells inhabit burrows
on open sandy bottoms, from which they
emerge at the turn of the tide and crawl
about in search of food. Their prey consists
mostly of sand-dwelling sea urchins and
sand dollars.
Phalium bisulcatum, is the most common
species of the Borneo seashore locally,
although Phalium (Phalium) bandatum
has also been found, though this may be a
Holocene (fossil) specimen (Ref 9).
Helmet Shell Phalium
bandatum (HD)
14
(Phalium)
The Seashells
Horn Shells
Vertagus Horn Shell Rhinoclavis vertagus Linnaeus, 1758, 30-50 mm. Fam. Cerithiidae
Telescope Shell/Creeper (Berungun) Telescopium telescopium Linnaeus, 1758, 98 mm
Fam. Potamididae
Vertagus Horn Shell Rhinoclavis Vertagus (RM)
H
orn shells are elongated
spiral
shells,
with
rounded aperture and a very
short siphonal canal.
The Vertagus Horn Shell is of
medium to large size at 3050mm. It is quite thick and
robust, with a slightly tapered Telescope Shell/Creeper Telescopium telescopium (RM)
lip, and is generally yellowish
white. Members of this group have an upturned canal in the shell which
protects the siphon and allows them to live just beneath the surface in fine
calcareous mud of coral reef areas, from very shallow to deeper waters.
The elongated Telescope Shell or Telescope Creeper is distinctive for its
thick heavy shell with numerous flattened whorls and is one of the biggest
shells to be found locally. It is exposed in mangroves during very low tides
using its highly extendable proboscis to gather titbits from the mud surface.
The snail is edible.
15
The Seashore Life
of the Brunei Heart of Borneo
Limpets
Order Patellogastropoda or Siphonariidae
L
impets have a simple conical shell and attach themselves to the substrate
using their muscular foot. They can hold themselves against the rock
surface with very considerable force when necessary, enabling them to
withstand wave action, predation and also helping them to avoid drying
out during low tide, even when in full sunlight.
Small limpet or possibly false limpet amongst an oyster covered rig block substrate (RM)
16
The Seashells
Limpets are only occasionally seen along the HoB beaches due to the lack
of hard surfaces. However shown here is a very small (1 cm) example along
with oysters on a rig support block.
The example shown be a true Limpet ie a Patellogastropod but it may also
be a representative of the Siphonariidae or False Limpets which always occur
high in the littoral zone. The latter breathes through a siphon that emerges
on the side of the shell, which therefore always has a small part of the shell
protruding from the otherwise ellipsoid shape.
A rig support block offering a rare hard substrate on local beaches for numerous organisms.(RM)
17
The Seashore Life
of the Brunei Heart of Borneo
Mitres
Mitre Shells Mitra (Nebularia) aurantia aurantia Gmelin, 1791, 22 mm Fam. Mitridae
Ribbed Mitre Vexillum vulpeculum Linnaeus, 1758, 43 mm. Fam. Costellariidae
M
itres are so named
because of their
resemblance to the conical
peaked headware sometimes
worn by ecclesiastical
figures. The Mitridae are
a large family with quite a
lot of variability in size and
generally brightly coloured,
although the Costellariidae
has also many species with
more subdued tones. They
are characterised by their
spindle shape and the folds
or teeth on the inner lip
(columella).
They live buried under
the sand, only emerging to
hunt at night. Their long
and flexible proboscis is
used to inject a paralysing
venom into their prey
before consuming it.
Ribbed Mitres have strong
axial ridges and often
colourful spiral banding.
18
Mitre Shell Mitra (Nebularia) aurantia aurantia (RM)
Ribbed Mitres Vexillum vulpeculum (RM)
The Seashells
Moon Snails, Sand Snails Fam. Naticidae
Bladder Moon Snail Polinices (Glossaulax) didyma Roding, 1798, 28 mm
Nerite Sand/Ear/Moon Snail Sinum neritoideum Linnaeus, 1758, 29 mm.
Tumid Moon Snail (Tekuyong Putih) Polinices tumidus Swainson, 1840, 25 mm.
Tumid Moon Snails Polinices tumidus (RM)
T
here are more than ten moon snail species in the PNHS collection,
but the Tumid and Bladder Moon Snails are the most common. They
are edible shellfish, (16-39 mm) but fishermen don’t collect them locally,
preferring bigger bivalves. The shell is most often seen occupied by a hermit
crab, but the live mollusc may sometimes be observed at very low tides. It
is an aggressive carnivore that emerges at night to prey on other molluscs,
especially bivalves, by boring holes into their shells using an acid solution.
The holes drilled by Moon Snails and other predatory shellfish are often
evident on collected shells. The seabed is not a peaceful place!
In the late afternoon
its trail can be
observed on muddy
sand, but mostly it
burrows just below
the surface in search
of bivalves.
It often has an
attractive pure white
shell that is used
instead of pebbles in
the traditional game
of Congkak, although
Bladder Moon Snails Polinices didyma (RM)
19
The Seashore Life
of the Brunei Heart of Borneo
locally the specimens vary
from pure white through
various degrees of brown as
shown in the illustration.
The edible Bladder Moon
Snail Polinices didyma is
bigger than the Tumid
Moon Snail at 15 -40 mm,
and only exposed live at very
low tides. Although their
shells are nearly spherical,
these animals can inflate
their tissues with seawater
to make a wedge shape to
facilitate rapid burrowing
through sand and mud.
Nerite Sand Snail Sinum neritoideum(NY)
The Nerite Sand Snail or
Nerite Ear Snail has more
of an ear-like appearance
from the underside hence Moon Snail egg collars with Donax Clams for scale (RM)
its common name. The shell
is much smaller than the
animal and is almost obscured by the mantle lobes.
The eggs of the Moon Snails are cemented in a matrix of sand and hardened
mucus to form a “sand collar” of about 2 -3 cm diameter. The collar
terminology referring to the shape reminiscent of old fashioned separate
shirt collars.
Moon snails are not commonly eaten locally but are sold in markets in
Thailand and Vietnam. (Ref 3).
20
The Seashells
Mud Creepers (Tekuyong Sirok) Fam. Potamididae
Mud Creeper Cerithidea cingulata Gmelin, 1791, 17 – 43 mm.
Typical scene of live Mudcreepers forming a network of trails in the mangrove mud of Sungai Seria
(RM)
T
hese are small brown checked
conical gastropods, seen here
along with Common Buttontops.
The Malay name (“Sirok” means
to suck) refers to how it is eaten, as
the top is usually cut off the shells
before cooking. These gastropods
usually are found in mangroves; on
the beach the shells are invariably
occupied by Hermit Crabs, so the
shells may have been brought there
by the tide.
Mud Creepers C. cingulata, often inhabited by
Hermit Crabs, in a bed of Common Button Tops
(RM)
21
The Seashore Life
of the Brunei Heart of Borneo
Murex Fam. Muricidae
Drupella Murex Drupella rugosa Born, 1778.
Short Spine Murex Murex brevispina ornamentalis Vokes & Ponder, 1988, 48 mm.
Spine Murex Murex trapa Roding, 1798, 65 mm.
Turnip Shell Rapana rapiformis Born, 1778, 35 mm, 64 mm.
Short Spine Murex Murex brevispina ornamentalis (NY)
Spine Murex Murex trapa (HD)
M
urex
are
carnivorous
molluscs, living in shallow
sub-littoral waters.
Using an
acid secretion they bore holes
into bivalves and other shellfish,
corals, barnacles and echinoderms,
through which it can attack its prey.
The Murex family includes many
members that are highly attractive
and complex in structure, their
elongate shells highly sculptured
with spines or fronds. The shell
body consists of raised spiral ribs,
with a siphonal canal much longer
than the rest of the shell to protect
the siphon as it probes around
22
Turnip Shell Rapana rapiformis (NY)
The Seashells
looking for food. The
Turnip Shell in particular
has a unique aperture, but
is rare locally.
Drupella is a voracious
predator of coral, and
able to detect corals
by detecting chemicals
emitted by the coral body.
(Ref W6)
Drupella rugosa vs Brunei 5c coin (16.5 mm) (RM)
Nassa Mud Snail Fam. Nassariidae
Nassa Mud Snail Nassarius (Zeuxis) siquijorensis A. Adams, 1852, 32 mm.
Fine Line Nassa Nassarius (Zeuxis) concinnus Powys, 1835, 20 mm.
T
his small but fairly common shell
living in shallow water, mud and sand
is characterised by its long siphon, which
is waved about as the animal moves across
the bottom in order to detect their prey.
They are scavengers, drawn by the scent of
decaying crabs, fish and sometimes jellyfish
and on which they feed. They also hunt for
living animals such as bivalves or worms.
Sometimes the live shell is found in early
evening when the animals become active, in
pools created by sand bars.
The very first known form of personal
jewellery was made of Nassarius shells. These
were made 75,000 years ago in South Africa
(Ref W4)
Nassarius siquijorensis (HD)
23
The Seashore Life
of the Brunei Heart of Borneo
Nerites (Tekuyong timba) Fam. Neritidae
Exuvia Nerite Nerita (Theliostyla) exuvia Linnaeus, 1758, 30mm.
Striped Nerite Nerita (Ritena) balteata Reeve, 1855, 34 mm
M
ost Nerites live in intertidal areas, especially estuaries, where they are
attached to mangrove roots, rock, or man-made structures. Other
species of this family occur in fresh water or fully marine environments. The
Striped Nerite Nerita (Ritena) balteata is the most common in local estuaries.
Their shells are distinguished by a semicircular aperture which is straight
across one end. The operculum also has a strong tooth, which is whitish and
fairly thick, to lock it to the inside of the shell. This characteristic, together
with the ability to attach to the hard substrate, allows them to survive in the
rugged habitat of splash zone down to the intertidal zone. Nerites are edible
and a popular seafood in Brunei. The Malay name Tekuyong Timba, means
“Timba Snail”, a “timba” being the vessel used to bail water from boats.
Nerite Nerita exuvia (NY)
24
Nerite Nerita exuvia (NY) underside showing semicircular aperture
The Seashells
Olives Fam. Olividae
Common Olive Oliva oliva Linnaeus, 1758, 22 mm.
Wide Olive Anazola nebulosa Lamarck, 1811, 40mm.
The black (with white tip) variety of Common Olive Oliva Oliva is common locally (RM)
O
lives are commonly found
tunnelling at the end of a
circular track of attractive patterns on
the surface of wet sand during very
low tide. The super glossy surface and
streamlined shape readily identifies
them as rapid burrowers in the sand.
Although they feed on carrion,
they prefer to hunt other molluscs,
especially smaller snails and bivalves
that they engulf with their foot,
smother with slime then pull under
the sand to eat. They are often seen in
The orange variety of Common Olive Oliva
Oliva making a getaway (NY)
25
The Seashore Life
of the Brunei Heart of Borneo
mating pairs. They exhibit a variety of colour patterns, the orange and black
common olives being particularly attractive and easily found locally.
Common olives, mating pair (RM)
Olives: top Anazola nebulosa right and bottom Oliva oliva
Scale: Brunei 5-cent piece (1.5 cm diameter) (RM)
26
Common olive Oliva oliva feeding trails make a lovely abstract pattern on a
rain-flooded sand surface (RM)
The Seashore Life
of the Brunei Heart of Borneo
Sundials Fam. Architectonicidae
Picta Sundial Architectonica picta Phillippi, 1849
Clear Sundial Architectonica modesta Phillippi, 1849
Clear Sundial Architectonica perspectiva Linnaeus, 1758
Straw Sundial Heliacus (Grandeliacus) stramineus Gmelin, 1791
T
he name of this family comes from the Greek “architekton” which means
“master builder” in reference to the beautiful and detailed patterns on
the shells and the “spiral staircase” feature visible from underneath. It is 1050 mm in size, lives in water depth of 6 metres or more, and is commonly
washed ashore all along the Brunei coastline.
Sundials top left A. picta, top right A. perspectiva.(RM) (A picture of the Straw Sundial can be seen
in the collection of seashells near the front of the booklet)
28
The Seashells
Tibias Fam. Rostellariidae
Shin Bone Tibia Tibia melanocheilus A. Adams, 1854, 40 – 110 mm.
T
his is one of the
larger shells to be
found locally, but it is not
common. The extended
siphonal canal is a feature
that protects the Tibia’s
siphon, the soft fleshy tube
which serves to “smell” or
“taste” the water in order
to locate a possible source
of food. Another feature,
the “teeth” on the lip of
the aperture protects the
animal while feeding.
Long thought to be part
of the Strombidae family,
recent studies indicate
these “shin-bone shells”
should be recognised
as a separate family, the
Rostellariidae.
Shin Bone Tibea: Tibea melanocheilus (RM)
29
The Seashore Life
of the Brunei Heart of Borneo
Triton Shells
Natator Tadpole Triton Gyrineum natator Roding, 1798, 28 mm. Fam. Ranellidae
Reticulate Triton Distorsio reticularis Linnaeus, 1758, 54 mm Fam Personidae.
T
riton shells are
named after the
Greek god Triton, son
of Poseidon, god of the
sea. They are famous for
the large size of many
species, sometimes up
to ½ metre in length,
and their use as musical
horns by removing the
tip and blowing through
them. It is also famous as
one of the few predators
of the notorious crown
of thorns starfish.
Natator Tadpole Triton Gyrineum natator(HD)
The beautiful small
Natator Tadpole Triton
is relatively common
locally, although some of
the shells house hermit
crabs. The Tadpole
Tritons live in intertidal
areas under rocks.
The live Reticulate
Triton has a thin
periostracum with long Reticulate Triton Distorsio reticularis (NY)
bristles on its dorsal
surface, and the shell is usually a delicate pink in colour.
30
The Seashells
Tankard Shells Fam. Angariidae
Delphin Tankard Angaria delphinus Linnaeus, 1758, 37 mm.
S
ince it inhabits
intertidal areas of
coral rubble and broken
reef it is rare to find this
shell washed up on the
beach locally. The shell
is thick, strong and
heavy with a blunt spine;
the corneous (horny
and soft) operculum
Worn Tankard Shell Angaria delphinus, almost certainly Holocene
of Angaria is thin and fossil (NY)
transparent (compared
with thick, semi circular cat’s eyes operculum of Turban Shells allowing
them to withdraw deep into the interior of the shell. Live Tankard Shells
feed on algae and their spines are often covered with marine growth.
Top Shells Fam. Trochidae
Common Button Top (Terigai, Sigai) Umbonium vestiarum Linnaeus, 1758, 6-14mm.
Maculate Trochid Trochus maculatus Linnaeus, 1758, 35 – 50 mm.
Pyramid Trochid Tectus pyramis Born, 1778, 53 mm.
Radiated Trochid Trochus radiatus Gmelin, 1791, 20-35mm
T
he Trochidae are a
large family with
many species varying
from the tiny Common
Button Top to the quite
large Tectus and Trochus
shells. Trochus Top Shells
are shorter than they are
wide, while Tectus Top
Shells are taller than
they are narrow.
Tectus pyramis (above), Trochus radiatus, (below left) and Trochus
maculatus, (below right) (RM)
31
The Seashore Life
of the Brunei Heart of Borneo
The Top Shells have evolved their conical shape similarly to limpets, to
allow strong currents and surf to easily wash over without dislodging them.
They appear in a number of colours and variation in texture. They are
herbivores, feeding on algae. A wide variety of Trochus may be found at
the Empire Hotel at Jerudong, where the shingly areas of the beach at the
northern end of the complex are particularly rich in specimens.
The “Common”
Button
Top
is
certainly
common on local
beaches and is
second only to
the Donax Clam
in population of
the lower shore
face. A scraping
of the sand will
often reveal tens
if not hundreds
of these stunning
little creatures.
The shells are so
small that the
Common Button Tops Umbonium vestiarum and Donax Clams (RM)
fantastic variety
of colour and
pattern is easily missed by the casual observer, but in close-up the beauty of
these shells reveals itself. Local people string up the shells to make curtains.
The shellfish can also be used to make a tasty soup. However, pick them
up quickly as they are surprisingly quickly propelled by their muscular foot
back into the sand.
32
The Seashells
Tuns Fam. Tonnidae
Tonna dolium Linnaeus, 1758, 58 mm.
Tonna maculata Linnaeus, 1758, 55 mm.
Tonna tessellata Lamarck, 1816, 62 mm.
Tonna allium Dillwyn, 1817
Tuns Tonna tessellata (RM)
I
t’s quite rare to find these beautiful shells, and if stranded they are rapidly
taken by a shell collector. The live shellfish is found from tide level down
to great depth, and has a thick brown periostracum and many different
colour variations. “Tun” refers to the resemblance to a round English barrel
with raised metal straps. They feed at night, creeping up on their prey of
molluscs, echinoderms and sleeping fish and pouncing, propelled by their
large muscular foot. Jerudong beach, where land reclamation has used sand
from deep water off Jerudong, is a good location to find them.
Tuns from left : two specimens of T. dolium, T. tessellata and T. allium (HD)
33
The Seashore Life
of the Brunei Heart of Borneo
Turban Shell Fam. Turbinidae
Tumid Turban Turbo (Marmarostoma) cf. angyrostoma Linnaeus, 1758
Tapestry Turban, Cat’s Eye Turban Turbo petholatus Linnaeus, 1758, 65 mm.
T
urbos are medium sized shells (65 mm) hard, thick and solid with a
beautifully coloured pattern. The internal walls of the shell are lined
with mother-of-pearl (nacre). T. petholatus is considered the most beautiful
of all Turbos. The operculum is heavily calcified, thick and rounded and
looks like a Cat’s Eye. Rare locally since their habitat is near coral reefs. In
other parts of South East Asia, Turban Shells are extensively collected for
ornaments and buttons.
Cat’s eyes: examples of the Turbo’s operculum. (NY)
Tumid Turban Turbo (Marmarostoma) cf.
angyrostoma (NY)
34
Tapestry Turban, Cat’s Eye Turban Turbo
petholatus (NY)
The Seashells
Turritella Fam. Turritellinae
Turritella Turritella bacillum Kiener, 1835, 35 - 74 mm
Screw Turritella Turritella terebra Linnaeus, 1758, 34 – 125 mm.
L
ike a unicorn’s horn, with its long narrow cone shape, the Turritella is
one of the most distinctive and collected shells locally. Two species are
found: T. bacillum whose shell is chestnut brown although also seen faded
to orange on older specimens, and T. terebra, whose shell is light brown
to white with more pronounced ridges on the whorls. Turritellas are often
seen in abundance washed up during the monsoon period, November to
February, but can be found all year round usually as individual specimens.
Turritella Turritella bacillum (RM)
Screw Turritella Turritella terebra (HD)
35
The Seashore Life
of the Brunei Heart of Borneo
Vase Shell Fam. Vasidae
Vase Shell Vasum turbinellum Linnaeus, 1758, 75 mm.
Vase Shell Vasum turbinellum (NY)
Vase Shell Vasum turbinellum (NY)
T
he Vase Shell is large, very solid and heavy with fairly prominent
spiral bands and large ribs on which there are stout spines. It feeds on
bivalves and worms. Rare locally, with the example shown being probably
a Holocene fossil.
Volutes Fam. Volutidae
Melo-melo Melo melo Lightfoot, 1786, 35 – 170 mm.
M
elo melo is the biggest shell in
the PNHS collection. It is not
rare locally but mostly found only as
broken fragments. The Volute is a fast
moving carnivore, feeding on crabs,
sometimes fish and also prawn. It kills
its prey by enveloping and suffocating
it with its foot. It spends most of its
life buried in the sandy or muddy
bottom in shallow to deep waters. Melo-melo Melo melo (NY)
Used in the past as a drinking vessel and for baling out boats.
36
The Seashells
Wentletrap Fam. Epitoniidae
Pallasi Wentletrap Epitonium pallasi neglectum Adams & Reeve, 1850, 30 mm.
R
Pallasi Wentletrap Epitonium pallasi neglectum (NY)
arely found locally
these shells have
been much sought
after by collectors for
their unique aperture,
prized by the Romans
and still fetching a
high price today. The
name
“wentletrap”
means spiral stairway
in Dutch, and it is
the
characteristic
ribbing
in
the
spiralling
aperture
and the open whorls
that give the shell its
appeal. Wentletraps
are predators, and
have a varied habitat.
They might be found
on the soft bottom
of tide pools, shallow
and deep water and
also in the reef area
associated with coral
and anemones.
37
The Seashore Life
of the Brunei Heart of Borneo
Bivalves
B
ivalves are
exclusively
aquatic molluscs
with
two
symmetrical
valves with a
hinge at the
top, during life
held together
by
powerful
muscles and a
hinge ligament,
but in the shell
The characteristic marks of the sand trawl (RM)
collected on the
beach, usually
only the ligament remains holding the two valves together. In general
bivalves don’t move around much, but this varies much depending on
the life to which species have adapted. Oysters and mussels fix themselves
by attaching their shells to firm substrata through cementation or byssal
threads, but a few bivalves (e.g. most Pectinidae and Limidae) can swim
very well to escape predators. Also bivalves living in intertidal ranges have a
well-developed foot with which they can dig themselves in quickly whenever
they are washed out of the sediment.
Bivalves don’t have the radula that gastropods use for feeding. In fact they
are the only molluscs that don’t have a radula. Instead they use their two
siphons to feed by inhaling and expelling water while being safe in their
38
The Seashells
burrow. The water and food particles are drawn in through one siphon to
the gills where tiny, hair-like cilia move the water, and the food is caught
in mucus on the gills. From there, the food-mucus mixture is transported
along a groove to the palps which push it into the clam’s mouth. The second
siphon carries away the water. The gills also draw oxygen from the water
flow. Other bivalves use siphons to pick up sediment (detritus feeders)
or to eat other organisms (carnivorous bivalves). For vision, scallops have
complex eyes with a lens and retina, but most other bivalves have much
simpler eyes, if any. There are also light-sensitive cells in all bivalves, that
can detect shadows falling on the animal. Although many bivalves are
sedentary as adults, their eggs develop into highly mobile juvenile stages
that are dispersed far and wide.
Sand trawling for Kunau, a popular evening activity for many Bruneians (RM)
Donax (wedge and bean) clams are the most common bivalves on local
beaches, but their large relative, the Kunau Meretrix meretrix is the most
sought after by fishermen.
39
The Seashore Life
of the Brunei Heart of Borneo
Binge
Umbo
Anterior abductor
muscle
Heart
Liver
Posterior
abductor muscle
Stomach
Mouth
Exhalant
siphon
Anus
Excretory
organ
Foot
Inhalant
siphon
Gill
Gonad
Edge of
mantle
Main organs of a marine bivalve, based on a clam, drawn and annotated by Novi Dols
Main features of a clam shell (Muriel Gottrop Ref W15)
40
The Seashells
Ark Shells (Tambayangan), Fam. Arcidae
Ark Shell Anadara (Scapharca) deyrollei Jousseaume, 1893
Cornea Ark Shell Anadara (Scapharca) cornea Reeve, 1844
Granosa Ark Shell Anadara (Tegillarca) granosa Linnaeus, 1758, 40 mm.
Pilula Ark Shell Anadara (Cunearca) pilula Reeve, 1843
T
he shells of A. deyrollei (left)
and its larger cousin A. cornea
are distinguished by a long flat
hinge, giving an extensive area over
which to issue the byssal threads
they use to attach themselves to a
hard substrate. The shells, with a
resemblance to folded bird wings
have a brown or black marked
periostracum which is often hairy
and commonly conserved near the
margins but may extend over a
sizeable portion of the shell. There
are also marked ribs, the grooves
between being about half the width
of the ribs. It is a well-known edible
species, size up to 70mm.
The Pilula Ark shells in contrast have
a short hinge, a deeper shell with a
more pronounced umbo, and often
well developed colour banding.
However, watch out, the coloured
Anadara pilula are often Holocene
(Stone Age) fossils reworked and
stained over time. Fresh shells less
frequently washed up on the beach
are white with a brown, hairy
periostracum (Ref 9).
Anadara cornea (above) and the smaller Anadara
deyrollei (below) showing the brown remnants of
the hairy periostracum that originally may originally
have covered a sizeable portion of the shell (RM)
Anadara pilula, Reeve, 1843. Different colours:
stripes and orange and pink tints (RM)
41
The Seashore Life
of the Brunei Heart of Borneo
Asiatic Hard Clams Fam. Veneridae
Kunau Meretrix meretrix Linnaeus, 1758
T
his large (up to 13cm)
edible bivalve is much
sought after by local people
on local beaches, being
considered to have the finest
taste, and is sometimes seen
in Kuala Belait wet market.
The tool of choice for
harvesting is a flat bladed
implement which is dragged
Kunau Meretrix meretrix supper coming up! (RM)
an inch or so below the sand
to hit and unearth the large
shellfish. The markings on the sand from this means of shellfish hunting are
very distinctive.
Cockles Fam. Cardiidae
Cockle Vepricardium sinense Sowerby, 1844
A
ll cockles, although
varying in surface
texture and ribbing
have a basic heart shape,
hence the family name
from the ancient Greek
kardia meaning heart.
The cockle commonly
found locally is V.
sinense, with deep ribs,
elongated hinge and a
serrated edge.
42
Cockle Vepricardium sinense (RM)
The Seashells
Donax Clams Fam. Donacidae
Bean Clam Donax dysoni Deshayes, 1854, 10 – 15 mm. (Juveniles (Feb/Mar) 3-6 mm)
Faba Clam Donax (Latona) faba Gmelin, 1791
Incarnates Clam Donax incarnatus Gmelin, 1789
Wedge Clam Donax cuneatus Linnaeus, 1758, 25-35 mm.
P
robably the most common bivalve on local beaches, it is found at low
tide in huge numbers. Attractive banding and colouration is typical
of D. incarnatus, but by far the most abundant species is D. dysoni. Both
species have a wide distribution, far beyond Borneo. D. dysoni is also the
dominant species throughout the beaches on both sides of the Baram Delta
– from Tanjong
Lobang, Miri, to
Seria. (Ref 9)
There are so many
that those exposed
by wave action
often struggle to
burrow back into
the sand due to the
sheer number of
their
companions
underneath.
The
shells of this edible
mollusc are strongly
built, smooth and
wedge shaped. If
exposed, digging is
immediate and active,
with the streamlined
shell pulled almost
instantly into an
upright position, and
drawn down rapidly
into the sand.
Different species of Donax Clams, the four on left are D. incarnatus,
the next four Bean Clams D. dysoni. and the two on the right are
again D. incarnatus (RM)
Wedge Clam Donax cf. cuneatus (HD)
43
The Seashore Life
of the Brunei Heart of Borneo
Glass Shells
Window Pane Shell (Selisip, Kaping-kaping)
Placuna placenta Linnaeus, 1758, 85 mm. Fam. Placunidae
Raeta sp. Raeta (Raetellops) pulchella Adams & Reeve, 1850, Fam. Mactridae
Window Pane Shell Placuna placenta (RM)
T
ransparent shells have been found on local beaches in two forms. The
large (10cm) Placuna placenta commonly known as the Window Pane
Shell, is ten times the size of the drifts of tiny (8mm) transparent glass shells
Raeta (Raetellops) pulchella that accumulated on the Panaga beach in May
and June 2007 and also reported from Piasau Beach (Ref 9).
44
The Seashells
Drifts of Raeta (Raetellops) pulchella (RM)
45
The Seashore Life
of the Brunei Heart of Borneo
Oysters (Tiram) Fam. Ostreidae
Oyster Crassostrea and Ostrea sp.
Large individual oyster with 20 smaller oysters attached (RM)
O
ysters are sessile bivalves, which means they don’t move around, and
therefore no longer need a foot. The naming of individual oyster
species in SE Asia is not resolved (Ref 4) because for many species, the shape
of the shell is highly variable, conforming to the shape of the substrate and
neighbouring oysters and other organisms. This had led to confusion, along
with the realisation that many species cohabit together.
Oyster fragments are often found, probably broken off offshore structures.
The large (14.5cm) specimen shown comprises a single individual curving
from left to right covered with at least 20 smaller oysters and a barnacle. It
was found in a large pile of oyster shells on the shore of the Sungai Seria
estuary where the oysters had probably been dressed (flesh removed) by
returning fishermen.
46
The Seashells
Piddocks Fam. Pholadidae
Piddock Pholas (Monothyra) australasiae Sowerby, 1849
Piddock Pholas (Monothyra) orientalis orientalis Gmelin, 1791
P
iddocks, sometimes called “angelwings”, are unique in that one of the
piddock’s shells has a set of ridges or “teeth”, which they use to grind
away at stiff clay or soft rock and create tubular burrows. The shape of these
burrows is due to the
rotating motion of the
piddock as it grinds
the rock to make its
home. The piddock
stays in its burrow for
its eight year lifespan,
with only its siphon
exposed to take in
water that it filters
for food. When the
piddock dies, other
marine life such as sea
anemones, crabs and
other molluscs often
take over the burrow.
Piddocks, burrowing specialists left and centre: Pholas orientalis and
right Pholas australasiae (RM)
Two different species
are found locally. P.
orientalis is larger and has no radial ribs on the back side of the shell (at the
bottom of the picture) whereas in P. australasiae the ribs extend over the
entire shell. P. orientalis has a wider spacing of the ridges than P. australasiae
on the right.
47
The Seashore Life
of the Brunei Heart of Borneo
Razor Shell or Razor Clam (Pahat-pahat) Fam. Solenidae
Razor Shell Solen sp. up to 110 mm
A
very distinctive bivalve, known for its long narrow rectangular shape,
whose similarity to the old-fashioned cut-throat razor gives it its name.
The Razor Shell is a strong and quick burrower as its thin and narrow shell
slips easily through the sand.
It is famous for its burrowing prowess, and is considered able to burrow
faster than a man can dig! Its digging activity involves inflating the foot
hydraulically, extending down into the sand and anchoring the animal.
Deflation of the foot then draws the shell down while the shell squirts water
down into the sand, fluidizing the sand in its path. The foot is thought to
exert a pressure of 2 kg/cm2. (Ref W11)
At the other end from the foot the siphon emerges at surface to breathe and
feed. The siphon breaks easily when the animal is disturbed. In this way, the
animal probably avoids being dragged out of the sand by its siphon. The
Malay name is based on its resemblance to a chisel or “pahat”.
Damaged example of Razor Shell Solen sp. (RM)
48
The Seashells
Rays Shells Fam. Pharidae
Purple Rays Siliqua radiata Linnaeus, 1758
Winter Rays Siliqua winteriana Dunker, 1852
W
ith its radial
white “rays”
on a purple/blue
semi
translucent
background
the
beautiful
and
fragile S. radiata is
a relatively common
find
on
local
beaches.
The Winter Rays
S. winteriana is a
larger species with
transparent white
shell. The species
of this genus have
a radial ridge inside
the anterior (short
end) part of the
shell, which can
be seen from the
outside as a bright
white ray.
Purple Rays Siliqua radiata (RM)
Purple Siliqua radiata and white Siliqua winteriana (NY)
49
The Seashore Life
of the Brunei Heart of Borneo
Shipworms
Teredo (Tambilok) Fam. Teredinidae
S
hipworms are not worms at all, but rather
a group of unusual saltwater clams with
very reduced shells, notorious for boring into
(and eventually destroying) wooden structures
which are immersed in sea water, including
piers, docks and wooden ships. Sometimes
called “termites of the sea”, they are marine
bivalve molluscs often known as Teredo
Worms, although shipworms belong to several
genera (Ref W7).
Teredo Shipworm (Ref W7)
Locally, evidence of shipworm activity is seen in the multiple holes
penetrating beached logs. Its two shells, enclosing only the front end of the
body, function not as protection but as a tool, with ridged and roughened
surfaces used for boring.
Shipworm holes in driftwood (RM)
As can be seen in the picture, the clam lines its burrow with a calcareous
coating produced by its mantle to act as protection to its body. This
phenomenon was observed by 19th Century British engineer Brunel. Based
on this he designed a modular iron tunnelling framework - a tunnelling
shield - which enabled workers to successfully tunnel through unstable
ground, resulting in the Thames Tunnel, the first tunnel ever built beneath
a major river (Ref W7).
50
The Seashells
Terrestrial and
Fresh Water Snails
Apple Snails (Kalambuai) Fam. Ampullariidae (junior synonym Pilidae)
Golden Snail Pomacea canaliculata Lamarck, 1804, 40 – 60 mm.
Golden Snail Pila ampullacea Linnaeus, 1758, 50 mm.
Golden Snail Pomacea canaliculata showing variations in color and
striping (RM)
Golden Snail Pomacea
canaliculata
showing
watertight operculum (NY)
F
reshwater snail Pomacea canaliculata is a South American introduced
species and is very similar to the local Pila ampullacea. Both have a
large rounded shell of a brown to brownish green colour, sometimes having
darker stripes round the shell. They are peaceful freshwater herbivores and
nibble on vegetation in and around the drainage ditches. They are well
suited to life there as their operculum can close tight to prevent drying out
during dry periods. They have a system comparable to the gills of a fish (at
the right side of the snail body) to breathe under water as well as a lung (at
the left side of the body) to respirate air, fitting them well to a semi-aquatic
life.
In time of flood the shells are carried into the sea by rivers to be washed
ashore where they become a favourite home for the Land Hermit Crab.
51
The Seashore Life
of the Brunei Heart of Borneo
Land Snail Fam. Achatinidae (Terrestrial)
African Land Snail (Tekuyong Jipun) Achatina fulica Bowditch, 1822, 70 mm
T
he terrestial African Land Snail is an introduction into SE Asia and
another whose shell is washed into the sea from drainage ditches, and
snapped up by
Land Hermit
Crabs. It has
an attractive
r o u n d e d
conical shape,
almost twice
as long as it is
broad, brown,
but
with
significant
African Land Snail (Tekuyong Jipun) Achatina fulica (RM)
banding,
considered
to be caused
by variations
in the snail’s
diet. As it is
happy eating
a wide variety
of vegetation
it has been
popular as a
pet, and can
live up to six
years. It also
African Land Snail (Tekuyong Jipun) Achatina fulica (RM)
is edible and
was introduced into some SE Asian islands as a food reserve for GIs in the
Second World War. Locally it is considered to have been introduced by the
Japanese during WW2 hence the Malay name (Ref 21).
52
The Seashells
Cephalopods
Harvest Cuttlefish (Kalabutan) Sepia sp. Fam. Sepiidae
Sephia pharaonis Ehrenberg, 1831
I
n cephalopods the molluscan foot has evolved into tentacles, and the
eyes and nervous system are highly developed. In fact cephalopods are
considered the smartest of all molluscs. They move primarily by jet propulsion
as the siphon through which
it draws oxygenated water is
elastic and muscular, and can
rapidly contract sending out a
jet of water.
The cuttlefish is edible and Common cuttlefish Sepia sp. (Ref W9)
caught mostly at night when
fisherman use strong light to attract squid and cuttlefish, both in estuaries
and out at sea. During the day they hide away under ledges or in caves or
weed beds. The external molluscan shell has become an internal calcium
carbonate “cuttlebone” which is commonly washed up on local beaches,
and are often available in pet shops for cage birds to nibble as a calcium
supplement. There are various species of Sepiidae living off the Brunei
coast. The largest is Sepia pharaonis Ehrenberg, 1831. (Ref 9).
Cuttlefish “cuttlebone” (CO)
53
The Seashore Life
of the Brunei Heart of Borneo
Echinoderms
E
chinoderms belong to the
phylum
Echinodermata
which means “spiny skinned”
and the skin of these animals
is indeed covered with spines.
The phylum includes starfish,
sea cucumbers, brittle stars, and
crinoids. They have fivefold
symmetry (called pentamerism)
and move by means of hundreds
of tiny, transparent, adhesive
“tube feet” powered by a vascular
system that is a complex of tubes
and canals filled with water.
The body actually consists of five
equal segments, each containing
a duplicate set of various internal
organs. They have no heart,
brain, nor proper eyes (sea stars
have eyespots and brittle stars and
sea urchins have light sensitive
cells). Their mouth is situated
on the underside and their anus
on top. They are found either
washed up or can be located by
the impression they make on the
sand as they bury themselves.
54
Live sand dollar Echinodiscus truncatus top side (CO)
Keyhole sand dollar skeleton (RM)
The Seashells
Sand Dollar Fam. Astriclypeidae, Order Clypeasteroida
Keyhole Sand Dollar Echinodiscus truncatus L. Agassiz, 1841
S
and dollars usually burrow just below the surface of the sand and collect
detritus from the sand-water interface. The body is very flat, somewhat
circular in outline, and covered with minute spines giving it a velvety
appearance. The two slots in the sand dollar are called “lunules”. The petal
shape in the centre (petaloid) is where the sand dollar breathes. They move
by means of their tube feet and spines. E. truncatus is uncommon, but can
be found opposite the Panaga beach shelter at very low tide especially in
April-June.
Their skeletons are occasionally washed up but have to be handled carefully
if they are to be preserved for a collection as they are very fragile.
Live sand dollar Echinodiscus truncatus, underside
in evening light (RM)
Sand Dollar imprints on the sand after
burial (CO)
55
The Seashore Life
of the Brunei Heart of Borneo
Starfish Fam. Archasteridae, Class Asteroidea
Sand Star, Sea Star (Bintang Laut) Astrospecten sp.
S
tarfish are famous for their
radial symmetry, and several
arms, usually five, radiating from
a central body. Astrospecten is a
small starfish (5-6 cm), grey on
top and white underneath when
dead, and brownish on top when
alive. It is sometimes found washed
up in large numbers. Most starfish
Sea star Astrospecten sp. skeletons (RM)
are voracious hunters, preying on
other animals, particularly clams,
corals, other echinoderms, or anything else
unlucky enough to cross their path. They
have two stomachs, one used for digestion,
the other to extrude outward to engulf and
digest prey. This feature allows the starfish
to hunt prey that is much larger than its
mouth would otherwise allow.
During the day, the sea star is buried just
under the mud where you can sometimes
see the imprint. The central disc is a white
colour and the white spot of the madreporite
can be seen between the bases of the arms.
(The “madreporite” is the structure that
filters water for the sea star’s hydraulic
vascular system).
During the breeding season in April and
May, Astrospecten can be found in mating
pairs, the male on top, with its arms between
the arms of the female.
56
Sea Star Astrospecten sp. (CO)
Sea Star imprint on the sand after
burial (CO)
The Seashells
Coelenterata
Coral
F
ragments of coral are an unusual find
on local beaches although there are
coral reefs offshore and coral growths on
the legs of the production platforms.
Pieces of hard white coral skeletons that
appear on local beaches are probably all
Holocene Fossils. (Ref 9).
The example of branched red coral is
much more unusual, and appears to be
a basal section of the seafan Melithea,
which are fairly abundant on reef walls
in the Western Pacific and Indian Ocean
and on offshore structures.
Red coral is becoming endangered because
it is made of a magnesium/calcium
carbonate that is hard enough to make
into jewellery. Unfortunately it grows
very slowly, and the trawling techniques
commonly used to harvest the coral are
hugely damaging to the coral reefs.
Dead white coral fragment, possibly fossil.
(RM)
Red coral fragment, possibly seafan
Melithaea (RM)
The answer to this unsustainable trade is
for us all to stop buying coral jewellery.
Seafan Melithaea in situ (Ref W6)
57
The Seashore Life
of the Brunei Heart of Borneo
Crustaceans
Barnacles Balanus Fam. Balanidae
Acorn Barnacles Semibalanus balanoides
Giant Barnacle Megabalanus tulipiformis
Goose Barnacle Lepas anatifera
The biggest barnacle washed up locally, Megabalanus tulipiformis (RM)
A
corn barnacles are the most common barnacle found locally, followed
by the goose barnacle. These are usually found still alive and attached
to timber.
The biggest barnacle by far, and found quite often locally is Megabalanus
tulipiformis, with a huge opening some 2 cm wide.
58
The Seashells
59
The Seashore Life
of the Brunei Heart of Borneo
Fossil Shells
by Han Raven
B
eaches undergo constant change: generally growing between monsoons
and shrinking during the NW monsoon in particular due to longshore
drift and strong winds and tide. Shells washed up on the beach are usually
relatively fresh from animals actually living on the beach, in the sand
immediately below low tide level. Especially during storms with a seaward
wind (a rare event in Brunei) bottom currents can result that may deposit
Fossil shells from outcrops of the Miri (numbers 5 and 9) and Seria (the rest) Formations, NE of
Tutong - 1. Polinices tumidus, 2. Tonna sulcosa, 3. Althleta multispinosa, 4. Architectonica perspectiva,
5. Acila bruneiana, 6. Anadara cf. rotundicosta, 7. Amusium hulshofi, 8. Bathytormus foveolatus, 9.
Placamen lamellata, 10. Clementia papyracea, 11. Dosinia spec.
60
The Seashells
many live shellfish onto the beach.
However, most of the time only the
shells are washed up, their former
inhabitants having been consumed
along the way.
However, some shells are washed
up that have been buried for
much longer, maybe thousands or
millions of years, and are actually
therefore fossil shells. These may
be only a few thousand years old,
eroded from recent sediments by
particularly strong tides, currents
or waves, or changes in deposition
due to building of beach defences.
Older fossils also occur, generally
originating from layers exposed in
coastal cliffs.
Shark Tooth Penanjong Beach (Ref 10)
Older specimens are easily recognised
as fossils: the larger ones by their
duller colours such as cream or
grey and fainter or absent markings
compared to fresh shells, whereas
smaller fossils are often found in
pebbles.
In fine sediment (for example
mud) there generally are anaerobic
conditions in which shells lose
their original colours very quickly
and become bluish or greyish in
colour. This can be observed in a
very simple experiment: put a few
Melongena gigas, a large fossil gastropod found at
Penanjong beach by Charlie Lee probably from
the Seria Formation (HR)
61
The Seashore Life
of the Brunei Heart of Borneo
dead molluscs (with the animals) in an
airtight vessel topped up with water.
After only a few days the colours of the
shells will have disappeared to a dirty
white to dark grey. Watch it – there
will also be an awful smell, indicative of
the hydrogen sulphide (H2s) produced
during decomposition!
If the fossil was laid down in coarser
sediments there generally will have
been oxygen and the original colours
of skeletons may be preserved or they
obtain yellowish colours.
Holocene shell (Marginella ventricosa).
Subsequently the sediment will be common fossil shell on beaches from Muara
to Miri, always grey and dull colour (HR)
compacted and water flow will cause
the sand grains and enclosed fossils
to cement together. Some shell fossils have partially dissolved during this
process and therefore fall apart quickly when eroded by rain or sea, or when
cleaned too briskly by the collector. For such fragile fossils very little water
and a soft brush should be used. Some fossils have fully dissolved, and then
only the moulds of shells are preserved.
In Brunei such fossils originate from the Miocene to Pliocene shales and
sandstones of the Seria and Liang Formations exposed in cliffs between
Tutong and Muara (e.g. at Penanjong), which are between 2 and 10 million
years old. Seashells are the most common fossils, but also fossilised crabs,
solitary corals, shark teeth, and sea urchins can be found. A collection
of fossil shells from these outcrops collected in 1931 by geologists of the
Bataafsche Petroleum Maatschappij (now Shell), are in the National Natural
History Museum Naturalis, Leiden, The Netherlands and shown in the
figure above.
Many local fossils are Holocene fossils, with an age of only 8000 years or
62
The Seashells
less. They originate from a variety of deposits which have been eroded by
the sea, or which have been used to extend the beach such as at Jerudong
where young sediments dredged from near shore have been used to raise the
beach.
These coastal defence and construction activities sometimes disturb deposits
with abundant fauna which can tell us a lot about the geological history of
the area. It is worthwhile taking photographs, taking samples and noting
down the exact location if you come across such work. Such temporary
outcrops often disappear quickly (after day or weeks) but may provide
unique information.
Once you start to assemble your collection, you will notice that a number
of your shells, even some that are very common on Brunei beaches, are only
represented by fossil shells, so it’s worth knowing which is which!
63
The Seashore Life
of the Brunei Heart of Borneo
Displaying Shells
Wendy McIlroy’s glass top table shell display (RM)
S
hells need to be thoroughly cleaned before display. Thankfully most
of those found on the beach are dead and the previous occupant has
long gone. Just a wash to remove sand is usually all that is required. If
64
The Seashells
any remnant of the previous owner is still there find a quiet corner of your
garden and leave the seashell for a week or two and it will be cleaned for you
by ants and birds.
To store, airtight plastic containers or zip-lock plastic bags are ideal to
keep dust out. A bureau with thin drawers is also ideal. The serious shell
collector will keep shells of different localities and dates separate, with a
label comprising family name,
genus and species name, locality,
date, collector, and a description
of circumstances. Each collector
can decide how much detail to
record – but especially for rare
species it is valuable to keep proper
data. Note that there is very little
published about the seashells of
Borneo and anyone may find
species that have thus far not been
recorded for Borneo or that are
even new to science!
Containers with multiple drawers for nails and screws
can provide a suitable home for a shell collection, and
are available from many hardware shops (RM)
Shells look well displayed in rattan
or palm baskets, in glass jars or
dishes. A beautiful way to display
your shells is in a box frames on
the wall. Choose to frame shells
individually and cluster the frames
into larger groups on the wall or
create a dramatic composition of
a number of shells within a single
frame. A glass top table is also
another beautiful way to display
your best specimens.
65
The Seashore Life
of the Brunei Heart of Borneo
Photographic Notes
S
hells are of such variety of form, texture and colour that stunning
photographic images can be taken with a reasonable digital camera.
Roger initially used a Konica Minolta (now Sony) Dynax 7D digital camera
with an 18-50 mm zoom lens but has now moved on to a 12.2 megapixel
Sony 700 CDSLR-A700 camera with a 16-80mm Carl Zeiss Zoom Lens.
The camera has image stabilisation which is always “on” but other settings
are usually automatic. One important photography tip. Keep you camera
in a plastic bag in a warm part of your house (the toilet?) and let the camera
warm up in the bag when you take it out of doors, before shooting. Don’t
keep your camera in a cold air conditioned environment and take it straight
outside for photography. External condensation will prevent a good shot
and internal condensation can damage the camera.
The black background to some of the photos is a piece of black velvet,
available from fabric shops. The shells have been washed, dried and sprayed
or wiped with a light baby oil or mineral oil to give shine, although some
collectors frown on this as oil is difficult to remove and with time many
oils may become yellowish. Spraying with gloss varnish will also provide a
shine, but again frowned upon by serious collectors.
To see a variety of specimen shells photographed professionally against a
wide range of backgrounds, Ref 2 is the best source.
66
The Seashells
Glossary
Aperture Apex Base Bivalve Body whorl Brackish Byssal threads
Calcareous Callus Caudal Columella Corneous Deplete Deposit Desiccation Disperse Distribution Dorsal Estuarine Estuary principal opening from which the body parts of a gastropod
shell emerge
the starting point of a shell, at the end of the spire of a
gastropod shell with the smallest and oldest whorls
part of the shell surface opposite the apex
a mollusc with two-valved shell
last whorl of a gastropod shell next to the aperture, containing
all the major body parts except the visceral mass.
low salinity water, usually river water that has been mixed
with seawater
strong horny filaments used for attachment to the
substrate
consisting of calcium carbonate
thicker section of the aperture of a gastropod; it may partly
or completely cover the umbilicus
referring to the tail or the tail end of the body
solid or hollow axis of a gastropod shell
made of horn-like substance
to reduce greatly in quantity
an area where sediment is laid down
drying out
spread or move away from
the spread of an organism over geographic area
referring to the back or upper surface of a shell
relating to estuary
confined area around a river mouth, affected by tidal action
causing brackish water
67
The Seashore Life
of the Brunei Heart of Borneo
Filter feeder an animal that gets its food by filtering out suspended matter
from the water
Fossil animals and plant remains that after death were preserved in
sediments and turned into rock
Fossil record the list and description of fossils
Foot
muscular extension of a mollusc’s body used for
locomotion
Gastropod a group of mollusc characterised by a single shell
Geologic time the time span required for most geological processes, ranging
from thousands to millions of years
Habitat the type of place where a particular plant or animal normally
lives
Ikan fish in Malay
Inter-tidal area of the shore that is submerged at the high tide and
exposed at low tide
Invertebrate animal that lacks a backbone, usually small in size
Juvenile this term can be applied to any young animal or plant
Ligament more or less calcified, horny structure that holds the two
valves of a bivalve shell together
Lip
the edge of the aperture of a gastropod shell
Littoral between high and low tide (intertidal)
Mantle a layer in the body wall of the mollusc’s body that secretes
the shell
Molluscs
soft fleshy invertebrates usually covered by a shell
Operculum a horny plate on the foot of some gastropod that serves as a
lid to close off the shell to protect their soft parts
Outer lip outer edge of the aperture
Peristome edge of the aperture on the gastropod shell
Periostracum external skin covering or epidermis
Posterior
towards the rear or bottom end
Predation a way of life where an animal hunts other animals for
food
Prey an animal taken by a predator as food
Radula abrasive “tongue” used by gastropods for feeding
Sandstone a rock that is formed from sand
68
The Seashells
Sedentary not moving about; often permanently attached to the
substrate
Sedimentation the process of depositing sediment
Sediment material deposited by water or sand
Siphon a tubular organ used by molluscs to draw in or eject water
Siphonal
Canal extension, sometimes elongated from the base of the shell
to protect the siphon
Species
A group of organisms which through isolation, environment
or interbreeding have formed their own genetic race, and in
theory, will not produce offspring when mated with another
such race
Subspecies
A geographical variant of a species which is sufficiently
different to be recognised as such
Sub-littoral below low tide level
Spire all the whorls of a gastropod shell with the exception of the
body whorl
Substrate the material on which an organism lives
Subtidal below the low tide mark, always underwater
Suture line joining two successive whorls on a gastropod shell
Tekuyong a generic Malay word for snail
Terrestrial relating to land as opposed to air or water
Transition passing from one condition to another
Umbilicus central cavity in a gastropod shell, formed by the internal
walls of the whorls
Umbo the beak, or apex on a bivalve shell; the point from which
the shell begins to grow
Whorl complete single turn in a spirally twisted gastropod shell
Zooxanthellae uni-cellular plants living in symbiosis with various animals
such as corals and giant clams
69
The Seashore Life
of the Brunei Heart of Borneo
References
1) Wong, Marina et al, Common Seashore Life of Brunei, Brunei Museum, 1996.
2) Harasewych, M.G. Shells, Jewels from the Sea, Rizzoli International Publications
Inc 1989
3) Tan, Leo W.H., A Guide to Seashore Life, Singapore Science Centre, Revised
Edition, 1992
4) Tan, K.S, A Guide to Common Seashells of Singapore. Singapore Science Centre,
First published 2000
5) Tan, Ria and Alan Yeo, Chek Jawa Handbook. Simply Green, Singapore 2003
6) Ming Chou Lake, A Guide to the Dangerous Marine Animals of Singapore.
Singapore Science Centre 1993.
7) Dharma, Bunyamin, Recent & Fossil Indonesian Shells. Conchbooks 2005
8) Dharma, Bunyamin, 1988 and 1992 Siput dan Kerang Indonesia I and II
Indonesian Shells I & II Verlag Christa Hemmen
9) Raven, J.G.M. personal communication
10) Sandal, S.T., editor, 1996. The Geology and Hydrocarbon Resources of Negara
Brunei Darussalam- 1996 Revision. Bandar Seri Begawan, Syabas. 243 pp.
11) Morton, Brian & Morton, John, Seashore Ecology of Hong-Kong. Hong-Kong
University Press 1983.
12) Sabelli, Bruno, Simon & Schuster Guide to Shells. Simon & Schuster inc. 1980
13) D. Roberts, S. Soemodihardjo, W. Kastoro, Shallow water Marine Molluscs of
North-West Java. Lembaga Oseanologi Nasional. LIPI, Jakarta-Indonesia 1982.
14) Elkin. J. Sea Watch Report. Panaga Natural History Society, Brunei Darussalam
1991.
15) Raven, J.G.M., Notes on Molluscs from NW Borneo. 1. Stromboidea (Gastropoda,
Strombidae, Rostellariidae, Seraphidae). Vita Malacologica 1: 3-32. Dutch
Malacological Society, The Netherlands 2002.
16) Raven, J.G.M. & J.J. Vermeulen. Notes on molluscs from NW Borneo and
Singapore 2. A synopsis of the Ellobiidae (Gastropoda, Pulmonata – Vita
Malacologica 4: 29-62. Dutch Malacological Society, 2007
17) Marsh, Losette & Slack-Smith, Shirley, Sea Stingers. Western Australian Museum,
Perth 1986.
18) Coleman, Neville, What shell is that?. Paul Hamlyn Pty limited NSW 2099.
National library of Australia 1975.
19) Gopalakrishnakone. P. Dangerous Animals. Singapore University Press 1990.
20) Marina Wong and Aziah Hj Ahmad. Gastropods and Bivalves that have Vernacular
Names in Brunei. Brunei Museum Journal, Vol 9, 1994
70
The Seashells
Websites
W1) W2) W3) W4) W5) W6) W6) W7) W8) W9) W10) W11) W12) W13)
W14)
W15) Eddie Hardy’s Internet Guide to Marine Gastropods
A truly stunning site with huge amounts of data including thousands of images
and professional taxonomy listings.
http://www.gastropods.com/
Conchology Inc
Comprehensive site but very suspect guidelines for collecting; such as “the
steel bar is useful to reach animals which are hidden in rock crevices”.
http://www.conchology.be/en/home/home.php
Man and Mollusc
http://www.manandmollusc.net/
Wikipedia Commons: Nassarius
Wikipedia Commons: Turritella
Science Links Japan
http://sciencelinks.jp/j-east/article/200511/000020051105A0413502.php
Panaga Divers website
http://www.panagadivers.com/
Wikipedia: Shipworm Teredo
Wikipedia: Achatina fulica
Wikipedia Commons: Cephalopod (Jose Carvalho)
Wikipedia Commons: Textile cone (Richard Ling) (GNU)
Wikipedia: Razor Shell
Un regard sur les coquillages zonatus.com
http://pagesperso-orange.fr/zonatus/Liste/Galerie_vendus/Galerie_vendus.htm
Wikipedia: Gastropod
Wikipedia Commons: Bivalvia (Kim Lundgren, GNU Version 1.2)
Wikipedia Commons: Bivalvia (Muriel Gottrop)
71
The Seashore Life
of the Brunei Heart of Borneo
Checklist and Index to Species
Species
Page
The Seashells
1
Gastropods
4
Abalones
Ear Abalones Haliotis planata
6
Babylons
Spotted Babylon Babylonia borneensis
7
Conches
Dog Conch Strombus (Laevistrombus) canarium
or Strombus (Laevistrombus) turturella
Marginate Conch Strombus (Dolomena)
marginatus robustus
Vittate Conch Strombus (Doxander)
vittatus apicatus
8
Cone Shells
Figuline Cone Conus (Cleobula) figulinus
Hyaena Cone Conus (Chelyconus) hyaena
9
Cowries
Arabian Cowrie Cypraea arabica
Miliaris Cowrie Cypraea miliaris
Onyx Cowrie Cypraea onyx
10
Crown Shell
Crown Shell Hemifusus ternatanus
11
Ear Shells
Midas Ear Shell Ellobium aurismidae
Nuclea Ear Shell Cassidula nucleus
Panther Ear Shell Phythia pantherina
11
Fig Shells
Underline Fig Shell Ficus subintermedia
Variegated Fig Shell Ficus variegata
12
Frog Shell
Elegant Frog Shell Bufonaria cf. elegans
Rana Frog Shell Bufonaria rana
72
13
Location
Date
The Seashells
Species
Page
Location
Date
Harp Shell
Harpa articula Harpa articularis
13
Helmet Shells
Helmet Shell Phalium (Phalum) bandatum
14
Horn Shells
Vertagus Horn Shell Rhinoclavis Vertagus
Telescope Shell/Creeper Telescopium telescopium
15
Limpets
16
Mitres
Mitre Shells Mitra (Nebularia) aurantia
Ribbed Mitre Vexillum vulpeculum
18
Moon Snails (Sand Snails)
Tumid Moon Snail Polinices tumidus
Bladder Moon Snail Polinices (Glossaulax) didyma
Nerite Sand/Ear/Moon Snail Sinum neritoideum 19
Mud Creepers
Mud Creeper Cerithidea cingulata
21
Murex
Short Spine Murex Murex brevispina ornamentalis
Spine Murex Murex trapa
Turnip Shell Rapana rapiformis
Drupella Murex Drupella sp.
22
Nassa Mud Snails
Fine Line Nassa Nassarius (Zeuxis) concinnus
Nassa Mud Snail Nassarius (Zeuxis) siquijorensis
23
Nerites
Exuvia Nerite Nerita (Theliostyla) exuvia
Striped Nerite Nerita (Ritena) balteata
24
Olives
Common Olive Oliva oliva
Wide Olive Anazola nebulosa
25
Sundials
Clear Sundial Architectonica modesta
Clear Sundial Architectonica perspectiva
Picta Sundial Architectonica picta
28
73
The Seashore Life
of the Brunei Heart of Borneo
Species
Page
Tibias
Shin Bone Tibia Tibia melanocheilus
29
Triton Shells
Natator Tadpole Triton Gyrineum natator
Reticulate Triton Distorsio reticularis
30
Tankard Shells
Delphin Tankard Angaria delphinus
31
Top Shells
Common Button Top Umbonium vestiarum
Pyramid Trochid Tectus pyramis
Maculate Trochid Trochus maculatus
Radiated Trochid Trochus radiatus
31
Tuns
Tonna dolum
Tonna maculata
Tonna tessellata
33
Turban Shell
Tapestry Turban, Cat’s Eye Turban Turbo petholatus
Tumid Turban Turbo (Marmarostoma) angyrostoma 34
Turritella
Screw Turritella Turritella terebra
Turritella Turritella bacillum
35
Vase Shell
Vase Shell Vasum turbinellum
36
Volutes
Melo-melo Melo melo
36
Wentletrap
Pallasi Wentletrap Epitonium pallasi neglectum
37
Bivalves
38
Ark Shells
Ark Shell Anadara (Scapharca) deyrollei
Cornea Ark Shell Anadara (Scapharca) cornea
Granosa Ark Shell Anadara (Tegillarca) granosa
Pilula Ark Shell Anadara (Cunearca) pilula
74
41
Location
Date
The Seashells
Species
Page
Location
Date
Asiatic Hard Clams
Kunau Meretrix meretrix
42
Cockles
Cockle Vepricardium sinense
42
Donax Clams
Bean Clam Donax dysoni
Faba Clam Donax (Latona) faba
Incarnates Clam Donax incarnates
Wedge Clam Donax cuneatus
43
Glass Shells
Window Pane Shell Placuna placenta
44
Oysters
Oyster Crassostrea and Ostrea sp.
46
Piddocks
Piddock Pholas (Monothyra) orientalis orientalis
Piddock Pholas (Monothyra) australasiae
47
Razor Shell
Razor Shell Solen sp.
48
Ray Shells
Purple Rays Siliqua radiata
Winter Rays Siliqua winteriana
49
Shipworms
50
Terrestrial and Fresh Water Snails
51
Apple Snails
Golden Snail Pomacea canaliculata
Line Golden Snail Pila ampulacea
Land Snails
African Land Snail Achatina fulica
52
Cephalopods
Harvest Cuttlefish Sepia sp.
53
Echinoderms
Keyhole Sand Dollar Echinodiscus truncatus
Sand Star, Sea Star Astrospecten sp.
54
Coelenterata
57
Crustaceans
58
75
Quick identification Guides for Common Gastropods, drawn and annotated by Novi Dols.
About the Authors:
R
oger McIlroy has lived in Brunei Darussalam
with his wife and children since arriving
from their home country of Scotland in 2001.
Roger holds degrees in Geology and Petroleum
Engineering and has managed to combine his
work in this field with a keen interest in the
environment. This series of books draws on his
documentation of the facts and images of the
natural history around the Panaga area of Brunei
which has been their home.
He sees this series as a fitting gift to the people and
wildlife of Brunei Darussalam in recognition of
their hospitality and friendship during his stay.
N
ovi Ellya Yusniasita Dols was born in
Jakarta, Indonesia, and grew up sailing the
nearby Thousand Islands. Novi’s nautical interest
and love of biology led to her studying Marine
Biology in Universitas National in Jakarta. During
this time she was involved in the gazetting of the
Gunug Halimun National park, the construction
of artificial reefs in Bali and marine ecology work
in the Kepulauan Seribu. In 1995 she moved
to Brunei where she taught Marine Biology at
Muzium Brunei and led the Shell sponsored survey
of the Two Fathom Rock rig reef. Currently a busy
mother of three living near the beach her interest
naturally focussed on the shells and fish regularly
found and landed on the west Brunei beaches. In
her other life as a graphics artist she has illustrated
two of Brunei Shell’s annual calendars and many
other small publications.