Australian Shell Collectors Group is designed to bring together collectors from Australia & other co
Named after the apricot Prunus armeniaca for its extraordinary colour, Umbilia armeniaca is an iconic Australian cowrie. Endemic to South and Western Australia, it lives in deep water down toward 200 metres, although it is also known from shallow water in some isolated locations. This composite shows some of the variation seen in this attractive species.
Exquisite example of the Australian endemic bivalve Bassina disjecta, also called the ‘wedding cake venus clam’. Measuring 65 milimetres in length, this frilly and colourful specimen is also very large. From South Australia.
Members of the family Xenophoridae - commonly known as carrier shells - know how to accessorise with various marine debris they find along the way.
This particular specimen, of the species Xenophora pallidula, seems to favour ‘turrid’ gastropods, auger shells, and glass sponges. The composite shows three different angles to provide the full range of its ornaments.
From Great Barrier Reef, Queensland.
This extraordinary shell belongs to the gastropod Bolma aureola, of the family Turbinidae. It is sometimes referred to as the golden Turbo shell.
This specimen resides in the Australian Museum, and was collected in the Great Barrier Reef several decades ago.
Copyright Australian Museum.
Cone snails - Family Conidae
Cones are fearsome predators. Equipped with venoms among the most potent in the animal kingdom, they hunt for bristle worms, a wide range of fish species, even other molluscs. Upon detecting unsuspecting prey, they will act with blinding speed, unleashing a chain of functions in their complex venom apparatus – a large muscular bulb will contract, forcing a venom cocktail through a convoluted gland before it is injected through a sharp, hollow, often harpoon-shaped tooth held firmly by their proboscis. All of this happens in the blink of an eye. Different species flaunt different venoms, ingeniously adapted to incapacitate various prey. Venoms adapted to fishes act immediately, as otherwise the fish will easily escape before the venom takes hold. Others, targeting less mobile animals, can act more slowly.
Cone snails dissolve the inner parts of their shells to make room for the animal as it grows – a helpful feature when their prey can equal their own size. Some species have extremely thick, solid shells. Others, for instance Conus geographus, one of the most venemous of all cone snails, is extremely lightweight. This enables the species to hang suspended from a ledge while hunting schools of fish as they pass by.
The shells of cones display a dazzling variety of patterns and colours – these are just but very few examples of this diversity.
Showing 16 species and subspecies, this plate illustrates the diversity of sculpture and colour among the abalone family (Haliotidae). Some are common, others quite rare and restricted in their distribution.
Top row (left to right): Haliotis coccoradiata, H. brazieri, H. scalaris emmae, and H. scalaris.
Second row: H. rubra, H. ovina volcanius, H. ovina, and H. patamakanthini.
Third row: H. tuberculata, H. clathrata (top), H. rubiginosa (bottom), H. rufescens, and H. supertexta.
Bottom row: H. australis, H. elegans, and H. parva.
Specimens not to scale.
This vivid orange shell belongs to the species Turbo petholatus. The feature inside the aperture is called the operculum, which serves the purpose of sealing the animal firmly inside the shell, protecting it from predators. The operculum in Turbo species is sometimes referred to as ‘cat’s eyes’.
This specimen resides in the Australian Museum, and was collected in the Great Barrier Reef nearly five decades ago.
Copyright Australian Museum.
Ever wondered what a shell looks like on the inside? This composite image of the Australian species Buccipagoda kengrahami (Ponder, 1982) shows just that. The inner structure - normally hidden by the outer shell walls - is called the columella.
This bivalve, from Bruny Island in southern Tasmania, belongs to the Australian species Neotrigonia margaritacea of the ancient family Trigoniidae.
A major character used in identification of bivalves is the hinge, and in particular what is called the hinge dentition. The two bottom images of this composite show the internal valves, which in this group are nacreous (consisting of aragonitic mother-of-pearl). The teeth are the triangular, serrated structures that directly oppose each other in this view. When the valves close these actually lock into place, allowing them to shut firmly in order to protect the animal inside.
The length and width of this specimen are both approximately 30 millimetres.
One place, one species, endless variation - tests of the sea urchin Holopneustes inflatus from Sydney Harbour, Australia.
Found in all of the World's oceans and comprising over 300 living species, scallops (Family Pectinidae) are one of the largest of all bivalve families. While their colourful and ornate shells are their best known feature, the animals inhabiting these shells are remarkable in their own right. For instance, when threatened, many species will make their escape by using their valves to 'swim' away from danger. They also have a well-developed nervous system, as well as numerous simple eyes adorning the edge of their mantle.
Scallops constitute an important food source, and are frequently used as symbols in popular culture. They are also a very popular family with shell collectors.
This selection of no less than 102 sea urchin tests shows some of the incredible diversity of this group from every corner of the world. Forty-two species comprise this image, with representatives from the cold waters of the North Sea and southern Atlantic, through the Mediterranean and Red Sea, and throughout the Indian Ocean and the Pacific.
Some are very common, such as the bright orange, purple and golden specimens representing the European Echinus esculentus (esculentus meaning edible) - others are elusive deep-sea critters mostly surfacing through research expeditions. An example is the rich apricot-coloured Stylocidaris brevicollis seen here near the centre, which is a species favouring seamounts (underwater mountains) in remote parts of the Pacific Ocean.
Most of these specimens come from the Sea Urchin Science Centre and Gallery in Sydney, Australia - the only museum in the world solely dedicated to this often overlooked group. I have a direct link to the gallery on my website (see bio), where you can book a personalised tour to better familiarise with these amazing creatures.
Photo: Anders Hallan
What species is this?
Spines in sea urchins serve a wide range of functions, including defending against predators, mobility and attachment, feeding and respiration. Their appearance varies enormously - from blunt, to sharp (some are even venomous), straight to curved, short to long, or just plain bizarre - such as the trumpet-shaped spines furnishing the species Goniocidaris clypeata seen here in the top left corner.
All these spine-clad specimens are on permanent display at the Sea Urchin Science Centre and Gallery in Sydney, Australia.
Nacre, or mother-of-pearl, is known for its beautiful iridescence. For molluscs, however, it is an extremely durable mineral that offers protection against predators and the elements. In abalone, such as those seen here, the combination of nacre and sculpture can be quite spectacular.
Nacre is a form of aragonite, which together with calcite constitute the building blocks in mollusc shells. Both are so-called polymorphs of calcium carbonate.
The Sea Urchin Science Centre and Gallery is in Kurrajong, Sydney.
The rare, spectacular and unique sea urchins seen in this image represent only a fraction of those displayed at the Sea Urchin Science Centre and Gallery in Sydney, Australia. The centre is the only one of its kind in the World, and it is open to the public.
Seen here are tests - the internal skeleton - of the Class Echinoidea, commonly referred to as 'regular urchins'. Which one's your favourite?
Sand dollars are an order of generally flat, burrowing sea urchins called Clypeasteroida. The selection shown in this image consists of specimens from world-renowned sea urchin expert Ashley Miskelly's private collection. All of the remarkable examples seen here are on permanent display at his sea urchin science centre and gallery in Kurrajong, Western Sydney. Far from all being flat and round, these are selected to show some of the spectacular variety seen among this lesser-known group of urchins.
Many thanks to Ashley for allowing me to photograph his wonderful collection.
This assortment of sea snails are members of a venomous group of gastropods called ‘turrids’. All of the imaged species live in the deep sea, from depths of a thousand metres down to a staggering five kilometres.
What is life like at such depths? At five thousand metres, the pressure is equal to having a grand piano weighing down on every square centimetre of your body! The temperature is low and practically uniform, from pole to pole – just a few degrees Celsius. Abyssal plains - vast expanses of relatively flat seafloor in the very deep ocean - also lack natural barriers. Therefore, if you think about it, without big changes in temperature and other environmental conditions, and without physical obstructions like those we may see on land (mountains, deep valleys, even cities - all potential barriers depending on the animal), species are able to spread over vast areas. Consequently, some of these can be found from the Caribbean and the North Atlantic, right around to southern Australia. Species with such virtually worldwide distrubutions are sometimes referred to as cosmopolitan. The top right snail, Theta lyronuclea, is one such example.
Image by A. Hallan and F. Criscione, who, together with researchers from Europe, named and studied many of the species shown. In fact, around 40 species of deep-sea 'turrids' were named as a result of this collaboration
Image copyright: Australian Museum.
Very cool 3d scan of a Cypraea tigris by Macquarie University scientists.
This staggering diversity of forms, sculpture and colour is the result of over half a billion years of evolution. Shown here are representatives of all but one living classes of shell-bearing molluscs, namely Gastropoda, Bivalvia, Cephalopoda, Polyplacophora and Scaphopoda*.
Molluscs have existed at least since the Cambrian Period, which started nearly 540 million years ago. This is a time so ancient that all land on Earth was nothing but barren desert – back then there were no animals roaming forests or traversing grassy plains, nor did these habitats exist – in fact, the very first tentative green shoot of the very first plant had yet to emerge out of the ground. The oceans, however, teemed with life to the extent that with the onset of this period came the ‘Cambrian Explosion’ – so named because it brought an incredible richness of new life – even entirely new life forms – into existence. Based on evidence in the fossil record from around the globe, we now know that most of the classes of molluscs depicted here originated in this enigmatic period.
Several molluscan classes, like the ammonites (not shown here), have long gone extinct. Others, especially gastropods, have become incredibly diverse – they are even the only class to have conquered dry land (see bottom right example). We all know land snails are notoriously slow, but it may perhaps still be surprising to learn that it took them at least two hundred million years to get there? Patient creatures, indeed…
* The missing class – the Monoplacophora – is a deep-sea group so elusive it was believed extinct until the 1950s.
Paradusta hungerfordi coucomi (Schilder, 1964)
This beautiful Cypraeidae is a rare subspecies of Paradusta hungerfordi (G.B. Sowerby III, 1888). While the former is widespread and relatively common, coucomi is restricted to deep waters off the Queensland coast. Named after a prominent Queensland collector, coucomi is generally only available from old collections due to the reduced trawling activity in the state compared to its heyday, when specimens such as these came up as fishing by-catch.
This specimen is quintessential coucomi, and a superb example of the subspecies. It is currently listed at auction:
https://www.ebay.com.au/str/seagemsstore
Interested in seashells and other curious creatures of the sea?
On August 20-21 2022, Sydney Shell Club will host a spectacular weekend of the most incredible shells from around the world. Join local, national and international shell enthusiasts for a weekend of celebrating the wonder and diversity of shells from around the globe!
At Balgowlah RSL Memorial Club, Seaforth, Sydney.
Saturday 20th: 11am-5.30pm.
Sunday 21st: 11am-4pm.
Adult: $5
Family: $15
Children under 12: free entry + FREE shell! (Must be accompanied by adult).
Also: books, viewing of competition displays, and of course SHELLS!
See you there! 🐚
Photo: SeaGems Australia
This image shows an absolutely spectacular example of the iconic Australian sea urchin Microcyphus zigzag (L. Agassiz, 1846). This particular specimen is highly accentuated, and the quintessential example of the South Australian form, which is more contrasting in colour and pattern than the Victorian and Tasmanian forms.
This specimen is one among 40 rare and incredible sea urchins currently available on auction:
https://www.ebay.com.au/str/seagemsstore
Leporicypraea mappa (Linnaueus, 1758) in normal and UV light. The intense red colour shown under the UV lamp could be to ward off predators who see light at the ultraviolet end of the spectrum.
Sprouting spines like a cluster of prehistoric trees, the sea urchin species Goniocidaris mikado is both bizarre and utterly unique.
This specimen, and many others, can be seen displayed at the Sea Urchin Science Centre and Gallery in Kurrajong, Sydney. This new one-of-a-kind museum, both established and run by sea urchin expert Ashley Miskelly, is absolutely superb and highly recommended.
For more: https://seaurchinscience.com/
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Interested in seashells and other curious creatures of the sea? On August 20-21 2022, Sydney Shell Club will host a spectacular weekend of the most incredible shells from around the world. Join local, national and international shell enthusiasts for a weekend of celebrating the wonder and diversity of shells from around the globe! At Balgowlah RSL Memorial Club, Seaforth, Sydney. Saturday 20th: 11am-5.30pm. Sunday 21st: 11am-4pm. Adult: $5 Family: $15 Children under 12: free entry + FREE shell! (Must be accompanied by adult). Also: books, viewing of competition displays, and of course SHELLS! See you there! 🐚
Leporicypraea mappa (Linnaueus, 1758) in normal and UV light. The intense red colour shown under the UV lamp could be to ward off predators who see light at the ultraviolet end of the spectrum.
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