Shy Guy Lion
From the Super Mario Wiki
A Shy Guy Lion is essentially an otherwise normal lion that wears a Shy Guy mask over its face. Despite being a species, only one was ever seen and was shown to have a bad temperament. It appeared during The Super Mario Bros. Super Show! episode "Raiders of the Lost Mushroom".
Kolonel von Koop, having apprehended Mario, Luigi, Princess Toadstool and Toad after retrieving the Lost Mushroom from the Temple of Koopa, locked the quartet up in a tree hut, where he released a Shy Guy Lion on them. Mario used Luigi's plumber's snake to tame the Shy Guy Lion, causing it to mew like a kitten in fear. Mario then ordered the Shy Guy Lion to break out of the tree hut for them, allowing him and his friends to escape. After this, the Shy Guy Lion was never seen again.