Biology
Popplio (Ashimari in Japanese) is a pinniped Pokémon that is primarily blue. It has large eyes, a long, white snout with black whiskers, and round, pink nose. There is a small, rounded earflap on each side of its head. Around its neck is a light blue ruff, which extends past its shoulders. It has four flippers. The front flippers are larger than the hind, and have white markings separating its toes. Popplio is able to snort bubbles of water from its nose, which it uses as part of its battle strategy, and it can swim at 25 mph. On land, it uses the elasticity of its bubbles to perform acrobatic stunts and jumps.
Origin
Popplio is based on a sea lion of some sort, and one would guess a Hawaiian Monk Seal, but Hawaiian Monk Seals are earless seals, and Popplio is a sea lion with ears, not a seal without ears. Popplio's design is based on a clown, and it's bubbles are based on balls that sea lions do tricks with in the circus. It's acrobatic nature is obviously a reference to circus acrobats. Overall, Popplio is an amalgam of everything in the circus.
Popplio may be a combination of pup, pop, pōpō (Hawaiian for ball), and ʻīlio-holo-i-ka-uaua (Hawaiian for the Hawaiian monk seal; meaning "dog that runs in rough water"). Alternatively it may just be pop and Leo. (Leo means lion, and Popplio is a sea lion.)
Ashimari may be a combination of 海驢 ashika (sea lion), 鞠 mari (ball), and marine.