biospeleology

Tiny cave snail with muffin-top waistline rolls out of the dark in Laos

Tham Houey Yè cave (Vientiane Province, Laos), inhabited by the newly discovered “muffin-topped” snail species Laoennea renouardi.
Photo by Jean-Francois Fabriol.

A new species of tiny cave snail that glistens in the light and has a muffin-top-like bulge, was discovered by Marina Ferrand of the French Club Etude et Exploration des Gouffres et Carrières (EEGC), during the Phouhin Namno caving expedition in Tham Houey Yè cave in Laos in March 2019. The new species, Laoennea renouardi, is 1.80 mm tall and is named after the French caver, Louis Renouard, who explored and mapped the only two caves in Laos known to harbor this group of tiny snails. Only two species of Laoennea snail are known so far, L. carychioides and now, L. renouardi.

Caver and scientist, Dr. Adrienne Jochum, affiliated with the Natural History Museum Bern and University of Bern (Switzerland), as well as the Senckenberg Research Institute and Natural History Museum (Frankfurt, Germany) described the new species and its cave habitat together with co-authors: Estée Bochud, Natural History Museum Bern; Quentin Wackenheim, Laboratoire de Géographie Physique (Meudon, France) and Laboratoire Trajectoires (Nanterre, France); Marina Ferrand, EEGC; and Dr. Adrien Favre, Senckenberg Research Institute and Natural History Museum, in the open-access, peer-reviewed journal Subterranean Biology.

The new transparent “muffin-topped” snail, *Laoennea renouardi.*
Photo by Estée Bochud.

“The discovery and description of biodiversity before it disappears is a major priority for biologists worldwide. The caves in Laos are still largely underexplored and the snails known from them remain few in number,”
points out Dr. Jochum.

The fact that two species of tiny cave snails of the same group were found in two caves located in two independent karstic networks 3.4 km apart, caused the authors to question evolutionary processes in these underground hotspots of biodiversity. The authors hypothesise that the two caves might have been connected during the Quaternary, around 100–200 thousand years ago. In time, the river Yè might have formed a barrier, thus disconnecting the cave systems and separating the populations. As a result, the snails evolved into two different species.

A new species of tiny cave snail that glistens in the light and has a muffin-top-like bulge, was discovered by Marina Ferrand of the French Club Etude et Exploration des Gouffres et Carrie?res (EEGC), during the Phouhin Namno caving expedition in Tham Houey Yè cave in Laos in March 2019. The new species, Laoennea renouardi, is 1.80 mm tall and is named after the French caver, Louis Renouard, who explored and mapped the only two caves in Laos known to harbor this group of tiny snails. Only two species of Laoennea snail are known so far, L. carychioides and now, L. renouardi.

Caver and scientist, Dr. Adrienne Jochum, affiliated with the Natural History Museum BernUniversity of Bern (Switzerland), as well as the Senckenberg Research Institute and Natural History Museum (Frankfurt, Germany) described the new species and its cave habitat together with co-authors: Estée Bochud, Natural History Museum Bern; Quentin Wackenheim, Laboratoire de Géographie Physique (Meudon, France) and Laboratoire Trajectoires (Nanterre, France); Marina Ferrand, EEGC; and Dr. Adrien Favre, Senckenberg Research Institute and Natural History Museum, in the open-access, peer-reviewed journal Subterranean Biology.

Map of the two caves on opposite sides of the River Yè, Vientiane Province, Laos.
Image by Louis Renouard.

The fact that two species of tiny cave snails of the same group were found in two caves located in two independent karstic networks 3.4 km apart, caused the authors to question evolutionary processes in these underground hotspots of biodiversity. The authors hypothesise that the two caves might have been connected during the Quaternary, around 100-200 thousand years ago. In time, the river Yè might have formed a barrier, thus disconnecting the cave systems and separating the populations. As a result, the snails evolved into two different species.

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Original Source:

Jochum A, Bochud E, Favre A, Ferrand M, Wackenheim Q (2020) A new species of Laoennea microsnail (Stylommatophora, Diapheridae) from a cave in Laos. Subterranean Biology 36: 1-9.
https://doi.org/10.3897/subtbiol.36.58977

Ice Age survivors or stranded travellers? A new subterranean species discovered in Canada

The discovery of a new to science species of rare and primitive arthropod from the depths of a cave that was covered by a thick ice sheet until recently is certain to raise questions. In their study, published in the open-access journal Subterranean Biology, entomologist Alberto Sendra and local caver Craig Wagnell describe a new species of cave-dwelling, insect-like campodeid dipluran from the island of Vancouver (Canada) and discuss its origin.

According to the study, the dipluran’s presence could either mean that terrestrial arthropods have indeed been able to survive within the deep subterranean habitats during the Last Glacial Maximum period some 26,500 years ago or it is the result of related species having dispersed to the area during the deglaciation, making their way from as far as Asia.

Contrary to most people’s expectations, the new creature was discovered only an easy hike away from the nearest town of Port Alberni (Vancouver Island, British Columbia). There, cavers Craig Wagnell, Tawney Lem and Felix Ossigi-Bonanno from the Central Island Caving Club, together with Alberto Sendra, Alcala University (Spain), reported a remarkable, previously unknown species of dipluran from a couple of caves recently unearthed in the small limestone karstic area.

*The exit of the Kiku Pot cave (Vancouver Island, British Columbia, Canada).*

Named Haplocampa wagnelli, the new species pays tribute to co-author Craig Wagnell, “who has dedicated many years sampling and exploring in Vancouver Island caves”.

Unlike most cave-adapted campodeid diplurans, whose bodies and appendages are characteristically elongated and slender – a “trademark” feature for strictly underground arthropods – the new species has only slightly elongated antennae and legs and a thicker body. This is the reason why the researchers conclude that the species is not exclusively subterranean and is likely to also be present in soil habitats. On the other hand, its North American sister species seem to be even less adapted to life underground.

Interestingly, the scientists note close relationships between the genus (Haplocampa) of the new species and three others known from the two sides of the north Pacific Ocean: Pacificampa (Japanese Islands and the Korean Peninsula), Metriocampa (Siberia) and Eumesocampa (North America). According to the team, this is evidence for dispersal events where populations would cross over the old Bering Land Bridge, which used to connect America and Asia.

Furthermore, the new species is also one of the most northerly cave-adapted dipluran species, found at a latitude of 49º north. Some 26,500 years ago, its modern habitat would have been located underneath the Cordilleran Ice Sheet, part of the Late Wisconsinan North American ice sheet complex.

*Felix Ossigi-Bonanno and Craig Wagnell at the entrance of the Kiku Pot cave after their successful discovery (Vancouver Island, British Columbia, Canada).*

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Original source:

Sendra A, Wagnell C (2019) The cave-dwelling dipluran (Diplura, Campodeidae) on the edge of the Last Glacial Maximum in Vancouver Island caves, North America (Canada). Subterranean Biology 29: 59-77. https://doi.org/10.3897/subtbiol.29.31467

The first case of a Portuguese beetle living exclusively in groundwater

New to science, the species was named after Pluto, the ruler of the underworld in Greek mythology

A diving beetle demonstrating various adaptations to the life underground, including depigmentation and evolutionary loss of eyes, was discovered at the bottom of a clay pound in the cave Soprador do Carvalho, Portugal. The species turned out to be the very first in the whole order of beetles (Coleoptera) to be known exclusively from the underground waters of the country.

*The Soprador do Carvalho cave (Portugal) is the type locality of the newly described species Iberoporus pluto. Photo by Ignacio Ribera.*

Despite not being able to find any other specimens during their study – save for the single female, the team of Dr Ignacio Ribera, Institute of Evolutionary Biology (Spain) and Prof Ana Sofia P. S. Reboleira, University of Copenhagen (Denmark) identified the beetle as new to science, thanks to its unambiguous morphology in combination with molecular data.

*Profile view of the newly described species Iberoporus pluto. Photo by Ignacio Ribera.*

Aptly named Iberoporus pluto in reference to the ruler of the underworld in Greek mythology Pluto, the species was recently described in the open-access journal ZooKeys.

With a uniformly pale orange body measuring 2.8 mm in length and 1.1 mm in its widest part, the beetle is larger than the rest species known in its genus, and its appendages are longer and more slender. While blindness and depigmentation are clear adaptation to life away from sunlight, the elongated limbs and antennae reflect poor swimming abilities needed in a subterranean habitat. Going for 4 km in horizontal direction, Soprador do Carvalho is the largest in the Dueça cave system, located in the north-eastern part of the Sicó karst area in central Portugal. In recent years, the cave is being explored for tourism.

“The knowledge of the subterranean fauna from Portugal has significantly increased over the last decade, with the description of a high number of obligate subterranean species (tripling their number) and the establishment of new biogeographic patterns,” explain the authors of the study. “A high number of these species are stygobiont (i.e. confined to groundwater), mostly from wells in the north of the country, where evapotranspiration is higher.”

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Original source:

Ribera I, Reboleira ASPS (2019) The first stygobiont species of Coleoptera from Portugal, with a molecular phylogeny of the Siettitia group of genera (Dytiscidae, Hydroporinae, Hydroporini, Siettitiina). ZooKeys 813: 21-38. https://doi.org/10.3897/zookeys.813.29765

The first cave-dwelling centipede from southern China

Chinese scientists recorded the first cave-dwelling centipede known so far from southern China. To the amazement of the team, the specimens collected during a survey in the Gaofeng village, Guizhou Province, did not only represent a species that had been successfully hiding away from biologists in the subterranean darkness, but it also turned out to be the very first amongst the order of stone centipedes to be discovered underground in the country.

Found by the team of Qing Li, Xuan Guo and Dr Hui-ming Chen of the Guizhou Institute of Biology, and Su-jian Pei and Dr Hui-qin Ma of Hengshui University, the new cavedweller is described under the name of Australobius tracheoperspicuus in the open-access journal ZooKeys.

The new centipede is quite tiny, measuring less than 20 mm in total body length. It is also characterised with pale yellow-brownish colour and antennae comprised of 26 segments each. Similar to other cave-dwelling organisms which have evolved to survive away from sunlight, it has no eyes.

In their paper, the authors point out that Chinese centipedes and millipedes remain poorly known, where the statement holds particularly true for the fauna of stone centipedes: the members of the order Lithobiomorpha. As of today, there are only 80 species and subspecies of lithobiomorphs known from the country. However, none of them lives underground.

In addition, the study provides an identification key for all six species of the genus Australobius recorded in China.

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Original source:

Li Q, Pei S-j, Guo X, Ma H-q, Chen H-m (2018) Australobius tracheoperspicuus sp. n., the first subterranean species of centipede from southern China (Lithobiomorpha, Lithobiidae). ZooKeys 795: 83-91. https://doi.org/10.3897/zookeys.795.28036

Saving the Underworld: Clarifying the subterranean fauna classification for improved conservation

Inevitably, many habitats, including the particularly vulnerable subterranean ones, will continue being erased from our planet as a result of human activities and interests. The challenge is to protect the ones that are the sole habitats to certain organisms, so that their species are safe from extinction. Hence, it is essential that the distribution of every each one of them is clearly defined.

Brazilian scientists Prof. Eleonora Trajano, Universidade Federal de São Carlos, and Prof. Dr. Marcelo Rodrigues de Carvalho, Universidade de São Paulo, discuss the current classification system, its application and complexities in a paper published in the open access Subterranean Biology.

Nowadays, there are three categories of subterranean fauna accepted. Troglobites live exclusively underground and are usually characterised with reduced or lacking eyes and pale or transparent colors; troglophiles may live both in caves and on the surface, with individuals commuting between these habitats and promoting genetic interchange between subterranean and surface populations; trogloxenes use caves regularly, but must leave them periodically in order to complete their life cycle.

Throughout the years, many alterations and subdivisions have been applied to the classification used when determining whether a cave organism belongs exclusively to the subterranean habitat, or not, before concluding these three groups, also known as the Schiner-Racovitza system. It is important to separate them properly, since the destruction of a habitat to an endemic troglobite, for instance, would immediately wipe out its whole species, as it would be impossible for the animals to move away.

However, many historic publications do not feature enough details about the described species’ distribution, nor identification of the used classification, so that the information is unreliable. Furthermore, there have been times, when people have been even afraid to survey the underground habitats, led by beliefs and associations linking caves to the “World of the Dead”.

In their paper, the authors conclude that the only way to define the species status of subterranean organisms with certainty is to study each species’ dynamics over a period of at least three years, since animals may migrate on a seasonal and/or non-seasonal basis. Also, scientists need to study thoroughly the area outside the surveyed cave, while testing for sampling sufficiency at all times.

“When employing classifications of subterranean organisms, especially for conservation purposes, these conditions should be checked for reliability of the status attributed to them,” say the authors. “Misplacing these organisms within the Schiner-Racovitza categories impairs the efficiency of such policies.”

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Original source:

Trajano E, Carvalho MR (2017) Towards a biologically meaningful classification of subterranean organisms: a critical analysis of the Schiner-Racovitza system from a historical perspective, difficulties of its application and implications for conservation. Subterranean Biology 22: 1-26. https://doi.org/10.3897/subtbiol.22.9759

Species new to science named after a ‘Dungeons & Dragons’ character

Focused on terrestrial gastropods, more commonly known as land snails, a joint team of biologists from the Natural History Museum of Stuttgart, Germany and the Zoology Museum of São Paulo, Brazil, have been researching Brazilian caves.

In their latest paper, published in the journal Zoosystematics and Evolution, the scientists describe the fauna from several caves in central Brazil, including a new tiny species named after a character from the popular fantasy tabletop role-playing game Dungeons & Dragons.

The team of Dr. Rodrigo Salvador, Daniel Cavallari and Dr. Luiz Simone encountered a rich assembly of species, several of which measured only a few millimetres.

Beyond filling important knowledge gaps, they went even further, discovering a land snail new to science. While it is not uncommon for studies dealing with the invertebrate fauna to end up describing new species, this minute mollusc (nearly 2 mm in length) attracted extra attention. The team named it Gastrocopta sharae, after Shar, the goddess of darkness, caverns and secrets in Dungeons & Dragons.

“It’s a fitting name for a tiny snail that lives hidden in the dark recesses of a cavern,” explain the authors. “If your knowledge of mythological beings seems to have failed you, do not fret. Usually biologists tend to honour Greek and Roman deities when naming species, but the goddess Shar has a more colourful background. She is from Dungeons & Dragons, the most famous role-playing game in the world, currently in its 5th edition and a staple of geek culture.”

This is not the first time that Dungeons & Dragons has been immortalised in a species’ scientific name. In 2014, the very same team described another tiny snail, this time, one with a taste for deep waters, specifically those of the Atlantic Ocean. The scientists named it Halystina umberlee, after another Dungeons & Dragons goddess, Umberlee, who commands the harshness and perils of the sea.

Tropical snails are still poorly understood, and they are one of the most threatened animal groups – both from human activities and environmental changes. Moreover, since cave-dwelling invertebrates, in general, receive scarce attention from researchers, it should come as no surprise that cave-dwelling snails are even less known.

“Getting to know the fauna inhabiting each cavern is a demanding task, but a much-needed one,” note the researchers. “Caverns are known to have very fragile ecosystems and several lack proper protection, so works like ours are an important step for conservation efforts.”

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Original source:

Salvador RB, Cavallari DC, Simone LRL (2017) Taxonomical study on a sample of land and freshwater snails from caves in central Brazil, with description of a new species. Zoosystematics and Evolution 93(1): 135-141. https://doi.org/10.3897/zse.93.10995

Family of scaffold web spiders increased with ~20% following discovery of 43 new species

Recent study into spider specimens collected from across China, Indonesia, Philippines, Singapore, Thailand, Vietnam and Madagascar over the past 15 years, revealed the striking number of 43 scaffold web spiders that have stayed hidden from science until now. By describing the new species in a paper published in the open access journal ZooKeys, scientists from Sichuan University and the Chinese Academy of Sciences increase the number of a scaffold web spider family (Nesticidae), known from around the world, with about twenty percents.

The studied family of scaffold web spiders is a relatively small group of arachnids, which can be found at almost any locality, apart from Siberia, Central Asia, Northern and Southern Africa and places at high latitude. Prior to the study of Drs Yucheng Lin, Francesco Ballarin and Shuqiang Li, the species counted 245 in total, 12 of which are extinct and known from fossils only. A curious peculiarity in these spiders is their comb of serrated bristles, located on their rear legs, used to pull silk bands for their webs.

Although large-scale taxonomic surveys of scaffold web spiders have long remained scarce, recently the interest towards spider research in China and Southeast Asia has seen a significant rise. Thus, over the last 15 years, Chinese, American and European arachnologists have carried out several surveys, ending up with precious samples. As a result, Dr Yucheng Lin and his team followed with deeper morphological and molecular studies to discover remarkable diversity.

In their work, the researchers have also established a new genus (Speleoticus) for five previously known, but misplaced species, which spend a lot of their time taking shelter in caves.

The majority of scaffold web spiders occur in temperate areas of the Holarctic realm, where the species tend to be medium-sized, long-legged, and prefer cave-like environments. The species found in the tropical and subtropical areas are, on the other hand, usually smaller, with shorter legs, and can be quite often spotted outside, where they crawl in forest litter, on grass, and under stones.

Original source:

Lin Y, Ballarin F, Li S (2016) A survey of the spider family Nesticidae (Arachnida, Araneae) in Asia and Madagascar, with the description of forty-three new species. ZooKeys 627: 1-168. https://doi.org/10.3897/zookeys.627.8629

Species conservation profile of a critically endangered endemic for the Azores spider

Subject to continuing population decline due to a number of factors, an exclusively cave-dwelling (troglobitic) spider endemic to the Azores is considered as Critically Endangered according to the IUCN Red List criteria.

To provide a fast output, potentially benefiting the arachnid’s survival, scientists from the IUCN – Spider and Scorpion Specialist Group and the Azorean Biodiversity Group (cE3c) at University of Azores, where the main objective is to perform research that addresses societal challenges in ecology, evolution and the environment, also known as the three E’s from the centre’s name abbreviation, teamed up with colleagues from University of Barcelona, Spain, and the Finnish Museum of Natural History.

Together, they make use of a specialised novel publication type feature, called Species Conservation Profile, created by the open access journal Biodiversity Data Journal, to provide scholarly credit and citation for the IUCN Red List species page, as well as pinpoint the population trends and the reasons behind them.

The studied spider species (scientifically called Turinyphia cavernicola) is a pale creature with long legs, large eyes and a total size of merely 2 mm in length. These spiders never leave their underground habitats, which are strictly humid lava tubes and volcanic pits. There they build sheet webs in small holes and crevices on the walls of the caves.

Not only is the species restricted to a single island within the Azorean archipelago (Portugal), but it is only found in three caves. Furthermore, out of the three, only one of them is home to a sustainable large population. These caves are under severe threat due to pasture intensification, road construction and tourist activities.

Although there is not much information about the species distribution through the years, with the spider having been discovered as recently as in 2008, the authors make the assumption that originally there have been significantly greater populations. Not only have they studied thoroughly another fifteen caves located on the island without finding any individuals, but they have identified increasing anthropogenic impact on the habitat.

“The species original distribution was potentially very large compared with the current,” the scientists explain. “Relatively intensive searches in and around the current caves where the species occurs have failed to find additional subpopulations.”

“The trend of decline is based on the assumption that this species can occur in all these caves and that the absence is due to anthropogenic disturbance on caves during the last 50 years,” they note.

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Original source:

Borges P, Crespo L, Cardoso P (2016) Species conservation profile of the cave spiderTurinyphia cavernicola (Araneae, Linyphiidae) from Terceira Island, Azores, Portugal.Biodiversity Data Journal 4: e10274. doi: 10.3897/BDJ.4.e10274