They haven't done a Pegasus Pokémon (Ponyta, Rapidash, and Keldeo; horses or unicorns, no winged ponies)
Do people consider Luvdisc/Alolomolola flounders?
And a dolphin would be cool, although Gorebyss reminds me of one, with its shape and pink color (Amazon River Dolphins are pink)
Technically, Luxray is lion-like, IMO
Psyduck is kind-of a cross between a duck and a platypus