Manding Nguyen

Andy Glusenkamp is kind of like a detective for animals.

Andy's a herpetologist, which means he studies reptiles and amphibians.

He works at the San Antonio Zoo, and for the last 20 years, he's been working on a case, searching for a missing creature.

It's actually a white salamander, a blind one called the blanco-blind salamander.

Except for one time, 71 years ago, and then never again.

A gravel company was looking for water, and so they tore up some ground near a natural spring in San Marcos, a city between San Antonio and Austin.

And at the bottom of the trench were some of the weirdest creatures these workers had ever seen.

These four pale white salamanders with no eyes.

They looked like they were from another world.

So there were two left.

And then there was one.

No one has seen another live one since.

The salamander that was sent to UT Austin is the only specimen on the planet.

It's not alive, but it's preserved.

Vox Science reporter Benji Jones.

A dead preserved salamander isn't exactly glamorous.

Benji wasn't impressed by what he saw in front of him.

But the mystery of the blanco blind salamander captured his imagination.

You may have heard of categories like endangered or threatened.

These are animals that are at risk of extinction.