Tag: molluscs

Tiny new species of snail named after Picasso

Anauchen picasso is among 46 new species of microsnails discovered in Cambodia, Myanmar, Laos, Thailand, and Vietnam.

They say beauty is everywhere if we have eyes to see; a team of scientists looked at a tiny, 3-mm snail and saw art.

An international group of malacologists (researchers studying molluscs) led by Serbian PhD student Vukašin Gojšina and his Hungarian supervisor, Barna Páll-Gergely, was exploring snail diversity in Southeast Asia when a species unknown to science grabbed their attention, prompting them to name it after cubist artist Pablo Picasso.

Unlike most other snails, Anauchen picasso has rectangularly angled whorls that, according to the scientists, make it look “like a cubist interpretation of other snails with ‘normal’ shell shapes.”

A photo showing four views of a translucent, pink spiral snail shell with distinctive ridges and a spiral apex, with a 1-mm scale for reference. — *Anauchen picasso*.

The research team just published a 300-page article including the descriptions of 46 new species of microsnails from Cambodia, Myanmar, Laos, Thailand, and Vietnam.

Close-up of a black and white SEM image revealing a heart-shaped cavity with textured edges, scale bar shows 0.5 mm. — SEM imaging showing an enlarged apertural view of *Anauchen picasso*.

“Although the shell sizes of these snails are less than 5 mm, they are real beauties! Their shells exhibit extraordinarily complexity,” they say. “For example, the aperture (the ‘opening’ of the shell) is armed with numerous tooth-like barriers, which are most probably useful against predators. Furthermore, several of the new species have an aperture that turns upwards or downwards, which means that some species carry their shells upside-down.”

These apertural barriers and the orientation of the last whorl on the shell were among the primary characters that helped the researchers tell different snails apart.

Images A-F show various views and textures of a spiral shell. — Appearance of the last whorl A shouldered B rounded C keeled at the centre of the periphery D keeled above the centre of the periphery E keeled below the centre of the periphery F double keeled.

While many of these new species were collected recently, several, unknown to science until now, were found in the collection of the Florida Museum of Natural History, collected all the way in the 1980’s. It is likely (and in some cases, certain) that the locations where these snails were found have already been destroyed by deforestation and limestone quarrying, which are the major threats to locally endemic land snails in Southeast Asia.

Research article:

Gojšina V, Hunyadi A, Sutcharit C, Tongkerd P, Auffenberg K, Grego J, Vermeulen JJ, Reischütz A, Páll-Gergely B (2025) A new start? Revision of the genera Anauchen, Bensonella, Gyliotrachela and Hypselostoma (Gastropoda, Eupulmonata, Hypselostomatidae) of Southeast Asia with description of 46 new species. ZooKeys 1235: 1-338. https://doi.org/10.3897/zookeys.1235.145281

New clam species discovered in South Africa’s kelp forest

It was discovered while working on the 1001 Seaforest Species project, which focuses on raising awareness about the rich kelp bed ecosystems of South Africa.

A new study sheds light on the unexplored diversity of galeommatoidean bivalves, a little-known group of marine mollusks, from the western coast of South Africa. The research, led by Paul Valentich-Scott from the Santa Barbara Museum of Natural History, along with collaborators from the University of Cape Town, Sea Change Trust, Stellenbosch University, and the University of Colorado Boulder, offers a curious glimpse into the habitats, symbiotic relationships, and taxonomy of these interesting creatures.

An unusual galeommatid clam, Melliteryx mactroides, living in tidepools near Cape Town, South Africa. Video by Jannes Landschoff

Published in the scientific journal ZooKeys, the study focuses on four species of galeommatoidean bivalves collected from the Western Cape region of South Africa. Among these is one new species, Brachiomya ducentiunus. This small clam, which is only 2 mm (less than 1/8^th inch) in length, spends its life crawling between the spines of sea urchins.

The newly discovered species, *Brachiomya ducentiunus*, crawing on a sea urchin spine. Photo by Craig Foster

The new species has so far only been found in one locality in False Bay, South Africa, where it was found attached to the burrowing sea urchin Spatagobrissus mirabilis in coarse gravel at a depth of about 3 m. It has not been observed free-living, without the host urchin.

Brachiomya ducentiunus was discovered while preparing and working on the 1001 Seaforest Species project, a research and storytelling program aimed at increasing awareness of regional kelp bed ecosystems colloquially referred to as ‘the Great African Seaforest’.

Dozens of the new species crawling on the surface of a sea urchin. Photo by Charles Griffiths

“This study marks a significant advancement in our understanding of the biodiversity and ecological interactions of galeommatoidean bivalves,” says lead author Paul Valentich-Scott. “By uncovering the hidden lives of these small but ecologically important organisms, we hope to contribute to the broader knowledge of marine biodiversity and the conservation of these unique habitats.”

Co-author Charles L. Griffiths, emeritus professor at the University of Cape Town, says, “A large proportion of smaller marine invertebrates remain undescribed in western South Africa and almost any project that samples specialized habitats turns up many new records and species.”

The new clam species feeding between the spines of a sea urchin. Video by Craig Foster

In a similar vein, co-author Jannes Landschoff, marine biologist at the Sea Change Trust, says “Creating foundational biodiversity knowledge is a most important step to the humbling realization of how fascinating and uniquely diverse a place is. I see this every day through our work in the rich coastal waters of Cape Town, where an extensive underwater kelp forest, the ‘Great African Seaforest,’ grows.”

Research article:

Valentich-Scott P, Griffiths C, Landschoff J, Li R, Li J (2024) Bivalves of superfamily Galeommatoidea (Mollusca, Bivalvia) from western South Africa, with observations on commensal relationships and habitats. ZooKeys 1207: 301-323. https://doi.org/10.3897/zookeys.1207.124517

Tiny thorn snail discovered in Panama’s backyard

*Close-up view of live individuals of the new species crawling on a leaf.*

Discoveries of biodiversity at the Lilliputian scale are more tedious than it is for larger animals like elephants, for example. Furthermore, an analysis producing a DNA barcode – a taxonomic method using a short snippet of an organism’s DNA – is not enough to adequately identify it to the species level.

In the case of tiny thorn snails – appearing as minute white flecks grazing in moist, decomposing leaf litter – it is the shell that provides additional and reliable information needed to verify or question molecular assessment of these otherwise, nondescript critters.

*Broadleaf forest litter with white arrows indicating the newly described species on the leaves.*

However, at 2 mm, thorn snails are too small and fragile to handle and the few, if any, tangible details on the outside of the shells can only be seen using a high-powered microscope and computed tomographic (CT) images.

This is exactly how the interdisciplinary team of Dr Adrienne Jochum, Naturhistorisches Museum der Burgergemeinde Bern (NMBE) and University of Bern, Dr. Bernhard Ruthensteiner, Zoologische Staatssammlung Muenchen, Germany, Dr. Marian Kampschulte, University Hospital of Giessen and Marburg, Gunhild Martels, Justus-Liebig University Giessen, Jeannette Kneubühler, NMBE and University of Bern, and Dr. Adrien Favre, Senckenberg Research Institute and Natural History Museum Frankfurt, managed to clarify the identity of a new Panamanian species. Their study is published in the open-access journal ZooKeys.

Even though the molecular analysis flagged what it was later to be named as the new to science species, Carychium panamaense, the examination left no shell for the description of the new snail to be completed, let alone to serve as tangible, voucher material in a museum collection available to future researchers. The mini forest compost-grazer had to wait for another five years and Dr. A. Favre, who collected fresh material while traveling in Panama.

The new snail is currently the second member of the family Carychiidae to be discovered in Panama. The first Panamanian, and southern-most member of its kind in the Western Hemisphere, is C. zarzaae, which was also described by Dr. A. Jochum and her team along with two sister species from North and Central America. The study was published in ZooKeys last year.

Much like X-rays showing the degree of damage in a broken bone, CT images visualise the degree of sinuosity of the potato chip-like wedge (lamella) along the spindle-like mast (columella) inside the thorn snail’s shell. These structures provide stability and surface area on which the snail exerts muscular traction while manoeuvring the unwieldy and pointed, signature thorn-like shell into tight nooks and crannies. The alignment and degree of waviness of the lamella on the columella is also used by malacologists (mollusc specialists) to differentiate the species.

*These are computed tomographic (CT) images of the new thorn snail species.*

Normally, a study of a thorn snail’s shell would require drilling out minute ‘windows’ in the shell by using a fine needle under a high microscope magnification.

“This miserable method requires much patience and dexterity and all too often, the shell springs open into oblivion or disintegrates into dust under pressure,” explains Dr. A. Jochum. “By exposing the delicate lamella using non-manipulative CT imaging, valuable shell material is conserved and unknown diversity in thorn snails becomes widely accessible for further study and subsequent conservation measures.”

The authors are hopeful that C. panamaense and C. zarzaae, which both inhabit the La Amistad International Park, Chiriquí, will remain a conservation priority along with other animalian treasures including the Resplendent Quetzal, Three-Wattled Bellbird and the Crested Eagles.

The park is considered the 1st bi-national biosphere reserve, as it occupies land in both Costa Rica and Panama, and constitutes a UNESCO World Heritage Site since 1990.

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Original Source:

Jochum A, Ruthensteiner B, Kampschulte M, Martels G, Kneubühler J, Favre A (2018) Fulfilling the taxonomic consequence after DNA Barcoding: Carychium panamaense sp. n. (Eupulmonata, Ellobioidea, Carychiidae) from Panama is described using computed tomographic (CT) imaging. ZooKeys 795: 1-12. https://doi.org/10.3897/zookeys.795.29339

DNA study in the Pacific reveals 2000% increase in our knowledge of mollusc biodiversity

Lead author Dr Helena Wiklund examining specimens on the RV Melville in October 2013

Scientists working in the new frontier for deep-sea mining have revealed a remarkable 2000% increase in our knowledge of the biodiversity of seafloor molluscs.

The 21 mollusc species newly described thanks to the latest DNA-taxonomy methodology

Tweny-one species, where only one was previously known, are reported as a result of the research which applied the latest DNA-taxonomy methodology to mollusc specimens collected from the central Pacific Clarion Clipperton Zone (CCZ) in 2013. They are all described in the open access journal ZooKeys.

Among the discoveries is a monoplacophoran mollusc species regarded as a ‘living fossil’, since it is one the ancestors of all molluscs. This is the first DNA to be collected from this species and the first record of it from the CCZ mining exploration zone – a vast 5-million-km² region of the central Pacific that is regulated for seabed mining by the International Seabed Authority.

“Despite over 100 survey expeditions to the region over 40 years of mineral prospecting, there has been almost no taxonomy done on the molluscs from this area,” says lead author Dr Helena Wiklund of the The Natural History Museum in London (NHM).

Dr Wiklund undertook a comprehensive DNA-based study of the molluscs to confirm species identities and make data available for future taxonomic study. This was coupled with the expertise of the NHM’s Dr John Taylor, who led the morphological work.

The molluscs were found in samples taken on and in the mud surrounding the potato-sized polymetallic nodules that are present in high abundance across the CCZ. These nodules are the target for potential deep-sea mining being rich in cobalt, copper, nickel, manganese and other valuable minerals.

The data are vital for the future environmental regulation of deep-sea mining, but have also revealed surprising patterns.

“I was amazed to discover that specimens collected during the 19th century by HMS Challenger were probably the same as ours over a range of 7000 km, but that data lodged on genetic databases from closer but shallower depths is likely to be from a different species,” comments Dr Thomas Dahlgren, population geneticist at Uni Research, Norway and University of Gothenburg, Sweden, who studied in detail a species called Nucula profundorum.

“Our efforts are now focussing on studying the DNA from many more samples of this species to examine connectivity and potential resilience to deep-sea mining,” he added.

Dr Thomas Dahlgren sieving sediments to find new clam and snail species

“It is a simple truth that we cannot move forward on regulatory approval for deep-sea mining without fundamental baseline data on what animals actually live in these regions,” says Principal Investigator of the NHM Deep-sea Systematics and Ecology Research Group, Dr Adrian Glover.

“Our work has highlighted obvious gaps in our knowledge, but also shown that with even relatively modest effort, we can greatly increase our understanding of baseline biodiversity using DNA-taxonomy.”

Creating a library of archived DNA-sequenced samples from known species allows for the future possibility of using the latest environmental DNA (eDNA) methods to ‘search’ for these species using just tiny samples of mud or seawater.

“Its akin to forensic science’, says Dr Glover. “You can’t use eDNA to find the criminals or species unless you have a library of information to compare them too”.

All data and specimens from the study have been lodged at the NHM and online repositories to make them accessible for future study. Of particular importance are the frozen tissue collections, which are housed in the state-of-the-art Molecular Collections Facility at the NHM and available for loan or further DNA work.

Original source:

Wiklund H, Taylor JD, Dahlgren TG, Todt C, Ikebe C, Rabone M, Glover AG (2017) Abyssal fauna of the UK-1 polymetallic nodule exploration area, Clarion-Clipperton Zone, central Pacific Ocean: Mollusca. ZooKeys 707: 1–46. https://doi.org/10.3897/zookeys.707.13042

Three new mini thorn snails described from Georgia (USA), Belize and Panama

Although computer tomography (CT) is widely used in medicine, its application in micro snail identification is still at the pioneering stage.

However, Dr Adrienne Jochum from the Naturhistorisches Museum der Burgergemeinde Bern (NMBE), Switzerland and her interdisciplinary team of German and Swiss scientists (Dr. Alexander M. Weigand, University of Duisburg-Essen, Estee Bochud and Thomas Inäbnit, NMBE and the University of Bern, Dorian D. Dörge, Goethe University, Frankfurt, Dr. Bernhard Ruthensteiner, Zoologische Staatssammlung Muenchen, Dr. Adrien Favre, Leipzig University, Gunhild Martels and Dr. Marian Kampschulte, Justus-Liebig University Giessen) have recently applied it in their research, now published in the journal ZooKeys.

As a result of their revolutionary approach, the scientists report three new thorn snail species – tiny, colourless and highly fragile creatures that measure less than 2 mm and belong to the genus Carychium.

Much like X-rays showing the degree of damage in broken bones, CT scans provide access to snail shells. Differences, such as the degree of sinuosity of the potato chip-like wedge (lamella), elegantly gliding along the spindle-like columella, become visible. These structures provide stability and surface area to exert muscular traction while manoeuvring the unwieldy shell into tight cavities. The alignment and degree of undulation of the lamella on the columella is also used by malacologists (mollusc specialists) to identify different thorn snail species.

Conventionally, examination of this signatory character requires cutting a hole in the shell with a fine needle under the microscope. This tedious method requires a much patience and dexterity and, all too often, the shell cracks open or disintegrates into dust under pressure. By exposing the delicate lamella to non-manipulative CT scans, Dr. Jochum and her team have found the best method to differentiate not only thorn snails but also many other micro creatures.

Together with G. Martels and Dr. M. Kampschulte, Dr. Jochum described new micro snails for the first time using CT in East Asian hypselostomatid snails in 2014. The first subterranean Asian relative of the thorn snails (Koreozospeum nodongense), was also described by Dr. Jochum thanks to CT scans in 2015.

The scientists studied and compared thorn snails collected from Mexico, Florida (USA) and Costa Rica.

Curiously, the new species Carychium hardiei was discovered by accident by Dr. Jochum en route to the Atlanta Airport during a rest stop in Georgia (USA). The snail is named after the American naturalist and field biologist Frank Hardie. Another species, Carychium belizeense, was found in the Bladen Nature Reserve in Belize and is named after its country of origin. The third, Carychium zarzaae from Panama, is named after Eugenia Zarza, collector of material for this study, including this species.

In total, there are fourteen species of thorn snails known in North and Central America. Their distribution ranges from as far north as northern Ontario, Canada through North America (including Bermuda and Jamaica) and south through Central America to Costa Rica. Thorn snails also live as far north as northern Sweden and as far south as sub-equatorial Java. Worldwide, this genus spans the Nearctic, Palearctic and Indomalayan biogeographic realms.

Thorn snails live in tropical and temperate forests, meadows and riparian zones, where they comprise the decomposer community in leaf litter of ecologically stable environments.

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Original Source:

Jochum A, Weigand AM, Bochud E, Inäbnit T, Dörge DD, Ruthensteiner B, Favre A, Martels G, Kampschulte M (2017) Three new species of Carychium O.F. Müller, 1773 from the Southeastern USA, Belize and Panama are described using computer tomography (CT) (Eupulmonata, Ellobioidea, Carychiidae). ZooKeys 675: 97-127. https://doi.org/10.3897/zookeys.675.12453

New species of pea-size crab parasitizing a date mussel has a name of a Roman god

Tiny crabs, the size of a pea, dwell inside the mantles of various bivalves, living off the food filtered by their hosts. A new species of these curious crustaceans has recently been reported from the Solomon Islands, where an individual was found to parasitise a large date mussel.

Because of the new pea crab’s characteristic large additional plate, covering its upper carapace, giving it the illusion of having two faces, it has been named after Janus, the Roman two-faced god. Discoverers Dr Peter Ng, National University of Singapore, and Dr Christopher Meyer, U.S. National Museum of Natural History, Smithsonian Institution, have their findings published in the open access journal ZooKeys.

Being only the second species in the genus (the first was from Malaysia), the new pea crab Serenotheres janus can be distinguished by its broader carapace and other features. It is cream-yellow in colour. oo_106009

Both representatives of the genus are unique in having an additional large plate covering the upper side of the carapace. However, its purpose is still unknown. The two pea crabs are also the only known parasites of the rock-boring bivalves of the mytilid subfamily Lithophaginae.

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Original source:

Ng PKL, Meyer C (2016) A new species of pea crab of the genus Serenotheres Ahyong & Ng, 2005 (Crustacea, Brachyura, Pinnotheridae) from the date mussel Leiosolenus Carpenter, 1857 (Mollusca, Bivalvia, Mytilidae, Lithophaginae) from the Solomon Islands. ZooKeys 623: 31-41. doi: 10.3897/zookeys.623.10272

New land snail species from Australia shows dissection not necessary to identify molluscs

Dissection might prove unnecessary when identifying new molluscs after scientists Corey Whisson, Western Australian Museum, and Dr Abraham Breure, Naturalis Biodiversity Centre, the Netherlands, and Royal Belgian Institute of Natural Sciences, Belgium, described a previously unknown land snail based on its genitalia, yet without damaging the specimen in the slightest. The new species is published in the open access journal ZooKeys.

The biologists described the first new Australian land snail species of this family for the last 33 years thanks to micro-computed tomography (micro-CT) and reconstruction with specialised software. This novel method, likely applied for identification of molluscs for the first time in history, uses X-rays to create cross-sections of the genitalia, so that a 3D model can be created without damaging the specimen. This can be then compared to known related taxa’s genitalia in order to show if there are enough differences to prove species delimitation.

The scientists note that despite the satisfying results, micro-CT is time-consuming and “quite laborious” approach. “However, in the case of a single or just a few specimens, this may be an alternative to destructive dissection,” says Dr Abraham Breure in his personal blog.

The new land snail, called Bothriembryon sophiarum after Dr Abraham Breure’s wife Sophie J. Breure and Corey Whisson’s first daughter Sophie Jade Whisson, can only be found along a 180-kilometre line running across the escarpment and cliff tops of the Baxter Cliffs and Hampton Ranges in Western Australia. Given its restricted distributional range, it is considered a short-range endemic.

The mollusc is characterised with a slender high-spired shell, built specifically for the demanding nature of its habitat. Dwelling in rocky limestone substrate, which is often fractured with narrow cracks and fissures, the snail has developed a slender shell, so that it can move easily through cavities and under rocks. On the other hand, being predominantly cream in colour with reddish or greyish brown blotches, it successfully blends with the limestone.

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Original source:

Whisson CS, Breure ASH (2016) A new species of Bothriembryon (Mollusca, Gastropoda, Bothriembryontidae) from south-eastern Western Australia. ZooKeys 581: 127-140. doi:10.3897/zookeys.581.8044