Check out the various butterfly mounts hitting the Trading Post in Patch 11.1!
The initial Patch 11.1 build contains multiple butterfly mounts. It seems they will all be available in the Trading Post at some point after Patch 11.1 hits live servers.
Pearlescent Butterfly
“Take to the skies on a glittering, shimmering, pearlescent butterfly.”
Spring Butterfly
Ruby Butterfly
“The elusive Ruby Butterfly is highly sought after by Twilight Witches.”
Midnight Butterfly