The names of these owls used to be the reverse of each other.

The eastern screech-owl on the left used to have the scientific name Otus asio.  In 2004 the American Ornithologists’ Union renamed him to Megascops asio, but his old name is still found on the web.

The long-eared owl on the right is still named Asio otus.

For reasons of symmetry, I wish the AOU hadn’t renamed the screech-owl.

“Otus Asio, Asio Otus” was rather fun.

(both photos are from Wikimedia Commons.  Click here to see the original of the eastern screech-owl.  Click here to see the original of the long-eared owl.)