TORONTO -- The Earth's sixth mass extinction is underway, with 400 animal species disappearing from the planet in the past 100 years.

But that only covers the species we know about. There are still many parts of the planet where we've yet to catalogue everything that exists.

Another step was taken in that direction recently, when researchers in Guinea set up bat traps and discovered one species they'd never seen before.

In the video at the top of this page, CTV News Science and Technology Specialist Dan Riskin explains what we know about the unusually coloured Myotis nimbaensis.