Hidden beneath the Earth lurk blind piranha, microbes that might as well be from another planet... and elephants. Read on for seven weird creatures found underground, including...
Tentacle-Mawed Leeches Beneath the MountainsIn 1995, explorers in the Croatian Velebit mountains discovered Slovačka jama, a massive pit splitting into channels that finished 1320 meters underground. In the darkest depths of the cave system, researchers encountered a new species of cave leech. The alien-looking beast was eking out a living on the dripping rocky walls and shallow pools, despite temperatures hovering around 5°C.
Labelled Croatobranchus mestrovi, these seemingly eyeless invertebrates have a pale pink, white or yellow body. They have wide mouths surrounded by tentacles, which the leech orients against the direction of water flow. This implies that the leech collects food from the onrushing water – unlike their surface-dwelling kin, they have no access to blood.
The venom itself is a lethal cocktail of enzymes and paralytics, all the better to immobilize a victim and liquify their organs. The remipede slurps out the resulting biological soup, before discarding the empty husk.
We don’t know how dangerous the venom is to humans – the necessity of diving through underwater tunnels to even find them is risky enough.
Stygichthys typhlops was initially discovered in a communal well used by the people of Jaiba in Brazil. Researchers realized that the strange-looking fish was a member of the order Characiformes - alongside the piranha. The lack of other specimens led researchers to believe that it was highly endangered or had become extinct shortly after the capture.
Much later, a group of researchers questioned locals regarding sightings of the unusual fish. They eventually determined that the creature lived in the subterranean waters connecting the wells. Unfortunately the arid conditions of the area and a growing demand with limited supply had begun to exhaust the underground water.
These blind fish differ wildly from other members of their order (known for strong eyesight) and they that are thought to be the troglodytic relics of a long-extinct surface fish. The species has only been found in the 25km long aquifer feeding the wells - they will go extinct when it runs dry.
Mineral-Munching MicrobesMost life on Earth depends on energy from the Sun – but not all. Researchers have found a lightless community of microbes 2 miles below ground in a South African gold mine. Isolated from the sun for millions of years, these organisms rely on hydrogen released as geological radiation “cracks” groundwater.
The heated sulfur-filled pressurized salt-water pools these creatures live in are inimical to human life. In a strange twist, exposure to the surface atmosphere proved equally lethal to the samples collected by the researchers.
The conditions in which these bacteria thrive are radically different to what we would traditionally consider viable – but they might offer insight into early life on Earth, or even other planets. This isn’t the only example of strange subterranean microbes either – researchers in Canada have found entities that consume pyrite (fool’s gold) in the depths of Kidd mine.
Discovered in 1887 by Maori Chief Tane Tinorau and surveyor Fred Mace, the earie display is provided by the larvae of fungus gnats. The hungry critters dangle silk strings dotted with sticky mucus to catch prey that comes too close. Once prey is caught on the line, the silk can be “reeled in” and the victim eaten alive.
The glow worms tailor their lines to their hunting grounds. In areas of the caves with strong air flow, lines are kept short to stop them from tangling. In contrast, stiller air allowed longer lines.
Spider-Hunting Assassin BugsA methodical killer lurks within the Kartchner Caverns of Arizona. The labyrinth bug (Phasmatocoris labyrinthicus) is a type of assassin bug – equipped with a sharp fused snout. It grapples prey with spindly forelegs and drives that snout through chitin to drain the fluids within.
The bug is very opportunistic, taking any prey small enough to grab. It also manipulates spiderwebs - and has been observed pulling them taught. This may be a tactic designed to trap spiders in their own silk, or perhaps to drag prey caught in the web close enough to steal.
This rare (there have only been around 10 sightings) bug has almost no physical adaptations towards cave life compared to other assassin bugs - though to be fair, it is pretty suited for a troglodytic lifestyle already. The only observed adaptation is a reluctance to take flight. Despite having wings, the bug prefers to walk and will attempt to flee predators on foot.
The extinct shield volcano is frequented by many wild animals that use it as a salt lick. The elephants take their tusks to the walls, gouging chunks of salt to crush and consume.
It should be noted that the cave is no safe excursion for the elephants. They stumble blindly through the darkness – and a deep crevasse lined with elephant bones is testament to both the risks and rewards of the depths.
- Tentacle-Mawed Leeches Beneath the Mountains
- Poison-Clawed Crustaceans
- Well-Dwelling Piranha
- Mineral-Munching Microbes
- Glow Worms that Fish for Flies
- Spider-Hunting Assassin Bugs
- Salt-Mining Elephants
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| Looks normal, but strange leeches lurk below... (infinitecroatia) |
Tentacle-Mawed Leeches Beneath the MountainsIn 1995, explorers in the Croatian Velebit mountains discovered Slovačka jama, a massive pit splitting into channels that finished 1320 meters underground. In the darkest depths of the cave system, researchers encountered a new species of cave leech. The alien-looking beast was eking out a living on the dripping rocky walls and shallow pools, despite temperatures hovering around 5°C.
Labelled Croatobranchus mestrovi, these seemingly eyeless invertebrates have a pale pink, white or yellow body. They have wide mouths surrounded by tentacles, which the leech orients against the direction of water flow. This implies that the leech collects food from the onrushing water – unlike their surface-dwelling kin, they have no access to blood.
Poison-Clawed Crustaceans
Found in the watery depths of Caribbean, Canary Island and Western Australian caves, remipedes are the only known venomous crustaceans. Resembling a centipede, these cousins of the shrimp are tiny and blind – their habitat has no natural light. They hunt using a set of hypodermic injectors on their front claws to poison their prey.The venom itself is a lethal cocktail of enzymes and paralytics, all the better to immobilize a victim and liquify their organs. The remipede slurps out the resulting biological soup, before discarding the empty husk.
We don’t know how dangerous the venom is to humans – the necessity of diving through underwater tunnels to even find them is risky enough.
Well-Dwelling Piranha
A blind fish with a translucent-pink coloration, this fish has the rare honor of being “rediscovered” by scientists after an extended investigation.Stygichthys typhlops was initially discovered in a communal well used by the people of Jaiba in Brazil. Researchers realized that the strange-looking fish was a member of the order Characiformes - alongside the piranha. The lack of other specimens led researchers to believe that it was highly endangered or had become extinct shortly after the capture.
Much later, a group of researchers questioned locals regarding sightings of the unusual fish. They eventually determined that the creature lived in the subterranean waters connecting the wells. Unfortunately the arid conditions of the area and a growing demand with limited supply had begun to exhaust the underground water.
These blind fish differ wildly from other members of their order (known for strong eyesight) and they that are thought to be the troglodytic relics of a long-extinct surface fish. The species has only been found in the 25km long aquifer feeding the wells - they will go extinct when it runs dry.
 |
| Bad for us, good for some microbes... (Simon) |
Mineral-Munching MicrobesMost life on Earth depends on energy from the Sun – but not all. Researchers have found a lightless community of microbes 2 miles below ground in a South African gold mine. Isolated from the sun for millions of years, these organisms rely on hydrogen released as geological radiation “cracks” groundwater.
The heated sulfur-filled pressurized salt-water pools these creatures live in are inimical to human life. In a strange twist, exposure to the surface atmosphere proved equally lethal to the samples collected by the researchers.
The conditions in which these bacteria thrive are radically different to what we would traditionally consider viable – but they might offer insight into early life on Earth, or even other planets. This isn’t the only example of strange subterranean microbes either – researchers in Canada have found entities that consume pyrite (fool’s gold) in the depths of Kidd mine.
Glow Worms that Fish for Flies
Looking like something out of an Avatar film, the Waitomo caves of New Zealand are festooned with neon blue biological fairy lights.Discovered in 1887 by Maori Chief Tane Tinorau and surveyor Fred Mace, the earie display is provided by the larvae of fungus gnats. The hungry critters dangle silk strings dotted with sticky mucus to catch prey that comes too close. Once prey is caught on the line, the silk can be “reeled in” and the victim eaten alive.
The glow worms tailor their lines to their hunting grounds. In areas of the caves with strong air flow, lines are kept short to stop them from tangling. In contrast, stiller air allowed longer lines.
 |
| Not what you'd expect in a cave... (Wolfgang_Hasselmann) |
Spider-Hunting Assassin BugsA methodical killer lurks within the Kartchner Caverns of Arizona. The labyrinth bug (Phasmatocoris labyrinthicus) is a type of assassin bug – equipped with a sharp fused snout. It grapples prey with spindly forelegs and drives that snout through chitin to drain the fluids within.
The bug is very opportunistic, taking any prey small enough to grab. It also manipulates spiderwebs - and has been observed pulling them taught. This may be a tactic designed to trap spiders in their own silk, or perhaps to drag prey caught in the web close enough to steal.
This rare (there have only been around 10 sightings) bug has almost no physical adaptations towards cave life compared to other assassin bugs - though to be fair, it is pretty suited for a troglodytic lifestyle already. The only observed adaptation is a reluctance to take flight. Despite having wings, the bug prefers to walk and will attempt to flee predators on foot.
Salt-Mining Elephants
The Kitum cave of Kenya is a 600ft deep hollow rich in salt. Situated in Mount Elgon, scores and furrows on the walls were thought to be the work of ancient Egyptian miners. It turns out that these are actually thanks to the efforts of salt-hungry elephants.The extinct shield volcano is frequented by many wild animals that use it as a salt lick. The elephants take their tusks to the walls, gouging chunks of salt to crush and consume.
It should be noted that the cave is no safe excursion for the elephants. They stumble blindly through the darkness – and a deep crevasse lined with elephant bones is testament to both the risks and rewards of the depths.
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