The Movile Cave in southeast Romania wouldn’t be at the top of your vacation destination list: it doesn’t catch any light, the air is thick with poisonous gases and it was cut off from the outside world for about 5.5 million years before it was accidentally shut off discovered in 1986.
However, life does exist in the Movile, and scientists have identified the largest creature they have found there to date. It is a troglobiont (or underground) centipede that has been given the name Cryptops speleorex, and it grows up to 52 mm (2 in) long.
The discovery brings the number of endemic species unique to the cave to 35, and it’s likely that there are many more to be found in this fascinating underground network – even if explorers can only manage in the caves for about 5-6 hours at a time.
The ‘king of the cave’ investigates his domain. (Mihai Baciu, GESS LAB, Mangalia)
“The centipede we described is a poisonous predator, by far the largest of the previously described animals in this cave,” say the researchers. “Given its top position in this subterranean system, we decided to name the species Cryptops speleorex, which can be translated to the ‘king of the cave’. “
Other creatures found in the depths of the Movile so far include water scorpions, leeches, and small spiders. They all depend on the nutrients provided by the oxidation of gases, including methane and sulfur by bacteria.
It’s the only ecosystem in the world that relies on this kind of chemosynthesis, but the cave is unusual in other ways too. After sitting in complete darkness for millions of years, many of the beings below are blind and completely colorless.
Some species in the Movile Cave can also be found beyond its borders, but C. speleorex is not one of them. The international team of scientists used DNA analysis to confirm that the centipede was indeed one that had never been seen before.
“ Our results confirmed our doubts and revealed that the Movile centipede is morphologically and genetically different, suggesting that it evolved over millions of years from its closest surface-treated relative to an entirely new taxon better adapted to life in the never-ending darkness, ”said the researchers.
Explore the cave. (Mihai Baciu, GESS LAB, Mangalia)
With about half the normal oxygen level in the air and plenty of hydrogen sulfide, methane, ammonia and carbon dioxide, the trips to the Movile Cave should be short for researchers. It is also extremely humid in the cave.
Only a small number of researchers ever visit the underground network – it involves a descent of 20 meters (66 feet) of rope, then a lot of scrambling through tight spaces to reach the central cave and swimming along underwater channels to see anything beyond .
From a scientific point of view, the trip is undoubtedly worth it. The organisms that call the cave home can teach us a lot about how life survives in the harshest of conditions, how it evolves in isolation, and even how it started on Earth to begin with.
For now, C. speleorex is the king of the cave – but it can’t be long before a greater creature is spotted deep in the darkness.
After all, there is always a bigger centipede.
The research is published in ZooKeys.