Shellos

Shellos (カラナクシ Karanakushi) is a -Type Pokémon introduced in Generation IV. It evolves into Gastrodon. Its colours and shapes differ between regions, but in the Sinnoh Region, two types are confirmed.

West Sea
The west sea Shellos it pink, with bumps on it's back. Both Shellos move like a slug. This is unsuprising, because it is the 'Sea Slug Pokemon'. In all, the West Sea Shellos isn't much different than the east sea Shellos.

East Sea
The east sea Shellos is mostly blue, with a soft green underbelly. There are strange wings on this Shellos' back.