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

Huge organs defy austerity for tiny cave snails in the subterranean realm

While most of the knowledge about tiny snails comes from studying empty shells sifted out from piles of dust and sand, the present research is the first contemporary microscopic exploration of organs in cave snails tinier than 2 mm. The paper, published in the open-access journal Subterranean Biology, reveals that underneath the seemingly fragile shells of the Zospeum genus, there are strikingly huge organs.

A number of remarkable observations such as an enormous kidney, grooved three-pointed teeth and a huge seasonally present penis are reported in the recent study, conducted by Adrienne Jochum, Naturhistorisches Museum der Burgergemeinde Bern, Switzerland, and her international team of researchers from University of Bern, Switzerland; Shinshu University, Japan; Universitaetsklinikum Giessen und Marburg GmbH, Germany; Justus-Liebig University Giessen, Germany; University of Ljubljana, Slovenia; University of Bern Goethe-University Frankfurt, Germany; Ruhr University Bochum, Germany; Croatian Biospeleological Society, Croatia and University Duisburg-Essen, Germany.

The scientists describe these characteristics as adaptations the miniature creatures have acquired in order to survive austerity in the subterranean realm.

Usually, adaptations to cave life can include blindness or lack of eyes, loss of pigmentation, sensitivity to changes in temperature and humidity, a high starvation tolerance, or anatomical compromises such as small size and transparent shells. The present study shows that miniscule carychiid subterranean snails have developed huge organs to tolerate the unique conditions of cave life.

“Studying adaptations in extreme environments such as those found in snails of subterranean habitats can help us to understand mechanisms driving evolution in these unique habitats,” explains the first author.

Glassy cave-dwelling snails known only from Northern Spain, the southern Eastern Alpine Arc and the Dinarides might have tiny hearts, but their enormous kidney extends from one to two thirds of the total length of their minute shells. This phenomenon could be explained as an effective mechanism used to flush out large amounts of excess water during flooding seasons in caves.

The same impressive creatures have also developed elaborate muscular plates, forming the girdle that surrounds the gastric mill (gizzard) in their digestive tract. The muscular gizzard grinds the grainy stew of microorganisms and fungi the snails find in moist cave mud. These mysterious creatures graze stealthily using an elastic ribbon (radula), aligned with seemingly endless rows of three-pointed, centrally-grooved teeth, as they glide through the depths of karst caves while searching for food and partners.

Deprived from the hospitable aspects of life we have grown used to, some of the snails discussed in the present paper have evolved their reproductive system in order to be able to reproduce in the harshest of environments, even when they fail to find a partner for an extended period of time.

As a result, not only are these snails protandric hermaphrodites, meaning that they possess male sexual features initially, which later disappear so that the female phase is present, but they have a large retractable, pinecone-shaped penis for instantaneous mating in the summer when mating is most probable. To guarantee offspring, a round sac, known as the receptaculum seminis, stocks sperm received from a partner during a previous mating and allows them to self-inseminate if necessary.

Teeth in these cave snails are also described using histology for the first time. They bear a median groove on the characteristic cusps known for the Carychiidae.

Sketchy, past dissections provide the current knowledge upon which the findings from this investigation are based. Otherwise, historical descriptions of these tiny snails are only known from empty shells found in samples of cave sediment. The genus Zospeum can only be found alive by inspecting cave walls using a magnifying glass.

“Knowledge of their subterranean ecology as well as a “gut feeling” of where they might be gliding about in their glassy shells is necessary to find them,” comments Adrienne Jochum. The authors also emphasize that this groundbreaking work is important for biodiversity studies, for biogeographical investigations and for conservation management strategies.

Adrienne Jochum and her team investigated the insides of the shells using nanoCT to differentiate species in synchronization with molecular approaches for genetic delimitation. Four well-defined genetic lineages were determined from a total of sixteen Zospeumspecimens found in the type locality region of the most common representative, Zospeum isselianum. This investigation is the first integrative study of live-collected Zospeum cave snails using multiple lines of data (molecular analyses, scanning electron microscopy (SEM), nano-computer tomography (nanoCT), and histology.

This work is dedicated to the industrious Slovenian malacologist Joze Bole, whose work greatly inspired the present research.

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Original source:

Jochum A, Slapnik R, Klussmann-Kolb A, Páll-Gergely B, Kampschulte M, Martels G, Vrabec M, Nesselhauf C, Weigand AM (2015) Groping through the black box of variability: An integrative taxonomic and nomenclatural re-evaluation of Zospeum isselianum Pollonera, 1887 and allied species using new imaging technology (Nano-CT, SEM), conchological, histological and molecular data (Ellobioidea, Carychiidae). Subterranean Biology 16: 123-165. doi: 10.3897/subtbiol.16.5758