A “Balrog” in the Tunnels: Scientists discover a new cave cricket species on the tiny island of Kastellorizo, Greece

This previously unknown species of cave cricket was found thriving within a network of man-made tunnels.

 Despite the intensity of modern exploration, the eastern Mediterranean continues to yield unexpected discoveries. On the small Greek island of Kastellorizo, researchers have documented a previously unknown cave cricket thriving within a network of man-made tunnels.

The species, named Dolichopoda balrogi, was described by researchers from Greece and published in the open-access Journal of Orthoptera Research. This discovery highlights how even small and seemingly ordinary habitats can shelter unique and previously unknown life.

A mysterious cricket in underground tunnels

The new species belongs to the genus Dolichopoda, a group of cave crickets that inhabit dark, humid environments such as caves, crevices, and underground spaces across southern Europe and the eastern Mediterranean. These insects are well known to evolutionary biologists because their isolated populations often evolve into distinct species on islands or in separate cave systems.

On the easternmost Greek island of Kastellorizo, researchers surveyed an artificial tunnel that serves as the island’s sole accessible land cave. To their surprise, they encountered a population of cave crickets bearing characteristics of the cave-dwelling genus Dolichopoda.

Detailed morphological and molecular study confirmed that the specimens represented a species new to science.

Artificial tunnel of Kastellorizo. Photo credit: Konstantinos Kalaentzis.

Why “balrogi”?

The species name balrogi was inspired by the Balrog, a legendary fire-demon from J.R.R. Tolkien’s The Lord of the Rings. In Tolkien’s story, the Balrog is an ancient creature hidden deep beneath the mountains, emerging from darkness. Its discovery is a fitting parallel; the cricket’s preference for deep, dark tunnel systems kept it outside the known record for decades.

The name also alludes to the circumstances of discovery of the species, which was found exclusively in a man-made tunnel. In Tolkien’s narrative, the Balrog is revealed only after the Dwarves “delved too deep”; similarly, Dolichopoda balrogi was discovered on Kastellorizo due to anthropogenic excavation on Mount Vigla, as the island lacks accessible caves. The epithet thus symbolically links deep excavation with the revelation of hidden subterranean fauna.

Dolichopoda balrogi sp. nov. Image credit: Konstantinos Kalaentzis.

Fortunately, unlike Tolkien’s fearsome creature, Dolichopoda balrogi is harmless – although equally well adapted to life in darkness.

Hidden biodiversity in unexpected places

Kastellorizo is a very small island, covering only about 9 square kilometers. Yet its position in the eastern Mediterranean between Asia and Europe makes it an important biogeographic hotspot.

Geographic distribution of Eastern Mediterranean Dolichopoda species. Image credit: © Environmental Systems Research Institute, Inc., CC BY 3.0.

The discovery of D. balrogi demonstrates that even small islands can host unique endemic species. It also suggests that artificial underground environments, such as tunnels and abandoned infrastructure, can function as refuges for specialised cave-dwelling organisms.

“These findings remind us that biodiversity discoveries are not limited to remote tropical forests or deep oceans. Even familiar landscapes and human-made structures can harbour species that have remained unnoticed.”

Konstantinos Kalaentzis

Protecting small and fragile ecosystems

Cave-adapted organisms like Dolichopoda crickets often have very restricted distributions, sometimes occurring in only a single cave or underground system. Because of this, they can be particularly vulnerable to habitat disturbance. The authors suggest that documenting and understanding these hidden species is an important first step toward their conservation.

Bayesian inference phylogenetic tree based on mitochondrial COI sequences of Dolichopoda species. Image credit: Konstantinos Kalaentzis.

As research continues across the Mediterranean, the researchers note that the countless Greek islands – many still poorly explored biologically – are likely to hold many more hidden biodiversity treasures awaiting discovery.

Cover image:

Newly discovered Dolichopoda balrogi sp. nov. in the artificial tunnel of Kastellorizo on 17 October 2025 – Female individual. Photo credit: Konstantinos Kalaentzis.

Original source:

Kalaentzis K, Alexiou S, Christopoulos A, Minoudi S, Koutsogiannopoulos D, Kotselis C, Triantafyllidis A (2026) Delving too deep: Morphological and molecular description of the cave-dwelling Dolichopoda balrogi sp. nov. (Orthoptera, Rhaphidophoridae) from Kastellorizo Island, Greece. Journal of Orthoptera Research 35(2): 259-266. https://doi.org/10.3897/jor.35.187943

For more interesting articles on orthoptera, visit the Journal of Orthoptera Research website and follow us on Bluesky and Facebook.

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

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, named Laoennea renouardi was described in the open-access, peer-reviewed journal Subterranean Biology.

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

Dragons out of the dark: 6 new species of Dragon millipedes discovered in Chinese caves

Six new species of Chinese dragon millipedes, including species living exclusively in caves, are described as a result of an international cooperation of research institutes from China, Russia and Germany. These cave species have unusually long legs and antennae, with one of them resembling a stick insect, only with a lot more legs. Others appear ghostly white and semi-transparent. The study is published in the open-access journal ZooKeys.

Underresearched in many tropical countries, numerous millipede species are still awaiting discovery and description in China as well. In the present study, three researchers from South China Agricultural University, the Russian Academy of Sciences, and Zoological Research Museum Alexander Koenig describe six particularly extraordinary new species of so-called ‘dragon millipedes’ from the two southern Chinese regions of Guangdong and Guangxi Zhuang. Both areas host a large number of spectacular caves, which have only recently been thoroughly surveyed. Four of the species never leave their underground homes.

Dragon millipedes, a genus of millipedes living in southeastern Asia, are characterised with their ‘armour’ of unusual spine-like projections. Furthermore, some of these species produce toxic hydrogen cyanide to ward off predators.

Among the public, the genus gained particular attention when the “Shocking pink dragon millipede” was discovered in Thailand in 2007. This discovery highlighted a large number of unknown millipede species in the Mekong region and worldwide. While the newly described cave dragon millipedes from China lack the “shocking” warning colour of their surface-living relatives, they are no less spectacular.

7825_Millipedes mating couple of Desmoxytes laticollis sp n

One of the new millipedes has received a formal name translating to the “stick insect dragon millipede” because of its extremely long legs and antennae. Therefore, it looks a lot like a stick insect, only with much more legs. Another two of the species have fully lost their colours, which is a common characteristic among exclusively cave-living animals. As a result, they appear ghostly white and even semi-transparent.

Miss Liu Weixin, PhD candidate at the South China Agricultural University in Guangzhou, China, and co-author of the present study, has conducted the research at the Centre of Taxonomy at the Research Museum Koenig (ZFMK), Leibniz Institute for Animal Biodiversity in Bonn, Germany as a part of her PhD, which focuses on Chinese cave millipedes. She worked along with her advisor and lead author Prof. Tian Mingyi, and renowned millipede expert Dr. Sergei Golovatch from the Russian Academy of Sciences, Moscow.

Over the course of her PhD, Miss Liu Weixin has explored more than 200 Chinese caves, where she has discovered over 20 new millipede species. The dragon millipedes are among her most spectacular discoveries as they exhibit extreme cave adaptations including loss of pigmentation and extremely elongated legs and antennae.

Still on her guest research year in Germany, Liu is currently busy describing additional batch of more than two dozen millipede species, she collected from the Chinese caves, literally bringing to light an unknown world.

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Original source:

Liu WX, Golovatch SI, Tian MY (2016) Six new species of dragon millipedes, genus Desmoxytes Chamberlin, 1923, mostly from caves in China (Diplopoda, Polydesmida, Paradoxosomatidae).ZooKeys 577: 1-24. doi: 10.3897/zookeys.577.7825