Mexican Tetra
Usually Found: Mexico
It is important that we point out that there are two forms of the Mexican Tetra species. One version of the fish species has eyes and several different colorations. Yet those that live in caves have lost all pigmentation and do not have eyes at all. The cave version is pretty cool, as it uses a form of echolocation like other blind species. While the cave-dwelling version is clearly meant to remain in the cave environment, they are actually pretty popular among aquarists.
This is why you’ve probably seen this species in a major aquarium you’ve visited in the last number of years. While the species gets its name from the region it’s located in, we should point out it’s also found in Texas. The non-cave version can also be found in the Rio Grande River, which travels through the United States and Mexico.