Cryptotora Thamicola is an extremely rare “evolutionary relic,” living in the caves of Indonesia. The scientists who discovered the species note the fish can climb waterfalls. What’s even more baffling is that the fish is completely blind, but it has still managed to survive for 400 million years.
Sharing its features with tetrapods, or four-footed animals, the Cryptotora Thamicola is a blind fish that was recently discovered in the caves of northern Thailand. The miniscule fish offers a very rare glimpse into the evolutionary process that happened some 400 million years ago. Incidentally, instead of offering some much-needed appendages to survive in the water, the fish was bestowed with a unique set of features that allows it not just to “walk” on the surface of rocks, but climb waterfalls.
The Cryptotora Thamicola, also referred to as the cave angel fish, is a rare species of fish found only in the Tham Maelana and Tham Susa karst formation in northern Thailand. These are giant caves with waterways that run for miles. The waterfall-climbing cave fish is quite small in structure. An adult can grow only to about 1.1 inches (2.8 cm).
Appearance-wise, it is devoid of any noticeable color or pigment. Astonishingly, the fish is blind because it lacks any visible eyes, reported Sci-News. The lack of vision is attributed to the fact that the fish thrived in the rather dark caves, where eyesight would have been rather futile. Being devoid of vision is quite common for species that live in extremely dark regions where sunlight doesn’t reach. While lacking eyesight is understandable, Cryptotora Thamicola’s ability climb walls and waterfalls, is truly fascinating, noted Dr. Brooke Flammang from New Jersey Institute of Technology, who identified unique anatomical features in a species of the blind fish,
“Cryptotora are found only in rapids and not in lentic pools. They are commonly observed climbing steep rock surfaces in fast-flowing waterfalls created by basalt or andesite intrusions. While it is anecdotally known that these fish can walk, the rare and protected status of these fish has limited research into the functional morphology of their walking behavior.”
Dr. Flammang and co-authors published a paper in the journal Scientific Reports this week. In the report, he notes the fish possesses some very unique and rather rare morphological features, which have so far been observed only in tetrapods,
“We show that the blind cavefish Cryptotora Thamicola walks and climbs waterfalls with a salamander-like diagonal-couplets lateral sequence gait and has evolved a robust pelvic girdle that shares morphological features associated with terrestrial vertebrates.”
How does the Cryptotora Thamicola climb waterfalls? This cavefish shares some features with early tetrapods, the creatures that first moved from water to land during the Devonian Period, reported The Daily Mail.
It owes its ability to scale slippery and wet walls of caves to a skeletal structure that has allowed the fish to develop a “gait,” scientifically referred to as “diagonal-couplets lateral sequence.” The fish moves forward by symmetrically alternating its pectoral and pelvic girdles, explained Dr. Flammang,
“The pelvis and vertebral column of this fish allow it to support its body weight against gravity and provide large sites for muscle attachment for walking.”
Essentially, Cryptotora Thamicola has a quite complex pelvic girdle that has never been observed in any of the 30,000 species of fish. It contains pelvic bones that are either loosely attached or remain suspended. Moreover, the fish appears to be in a transitional phase and has features associated with the evolutionary move from water to land.
Cryptotora Thamicola opens up a world of possibilities that will allow scientists to study the evolution of tetrapods when they ditched the water and moved inland to begin their life on terra firma, reported The Village Sun Times.
[Image via Screenshot]