Gastrodon is based on a sea slug, perhaps specifically of the order Opisthobranchia. The East Sea Gastrodon seems to be based on a sea hare.
Gastrodon is a combination of gastropod and don (Spanish for lord). It may also derive from Gastropteron, a species of sea slug.
Tritodon is a combination of from Tritoniidae or Triton (referring to either the common name of the gastropod genus Charonia) or the aquatic Greek god and don. It may also involve the word torito (Spanish for little bull, referring to its appearance).
No: 423
English Name: Gastrodon
Japanese Name: Gastrodon
Generation: 4
Type: Water, Ground
Species: Sea Slug Pokémon
Abilities: Sticky Hold, Storm Drain, Sand Force (hidden ability)
Evolution: Shellos > Gastrodon
Gastrodon is a sea slug-like Pokémon, and appears much the same as its pre-evolution, but it gains four more stubby legs and is noticeably larger. They both have plain black eyes with white irises, with a third eye in the center of their forehead. Like Shellos, Gastrodon has two forms.
In the West Sea form, the flower-like crest it had as a Shellos has now turned into horns adorning the side of its head, which point directly upwards in a crescent moon shape. Its underside up to the bottom of its mouth is pink, its back and the top of its head is completely brown, and it has two small protrusions on its back with several pink spots dotted around them. It also has two small protrusions on its neck underneath the horns, and it has a yellow border running down its body from its head, separating the brown and the pink coloration.
In the East Sea form, it retains the horns it had as a Shellos, although now fully colored green which point at a 45 degree angle. Its underside up to the bottom of its mouth is blue, its back and the top of its head is completely green, and it has two yellow “fins” adorned on its back with a third bordering its side and rear, as well as two small blue spots between them. It has a yellow border running down its body from its head, separating the blue and the green coloration.
Gastrodon and its pre-evolution Shellos are examples of allopatric speciation, though they are still able to breed. When it is threatened, it oozes purple fluid and flees. Gastrodon lives in shallow tidal pools.
POKEDEX ENTRIES
Pokemon Diamond: It has a pliable body without any bones. If any part of its body is torn off, it grows right back.
Pokemon Pearl: It apparently had a huge shell for protection in ancient times. It lives in shallow tidal pools.
Pokemon Platinum: Long ago, its entire back was shielded with a sturdy shell. There are traces of it left in its cells.
Pokemon HeartGold: When its natural enemy attacks, it oozes purple fluid and escapes.
Pokemon SoulSilver: When its natural enemy attacks, it oozes purple fluid and escapes.
Pokemon Black: Long ago, its entire back was shielded with a sturdy shell. There are traces of it left in its cells.
Pokemon White: Long ago, its entire back was shielded with a sturdy shell. There are traces of it left in its cells.
Pokemon Black 2: Long ago, its entire back was shielded with a sturdy shell. There are traces of it left in its cells.
pokemon White 2: Long ago, its entire back was shielded with a sturdy shell. There are traces of it left in its cells.
Pokemon X: When its natural enemy attacks, it oozes purple fluid and escapes.
Pokemon Y: It apparently had a huge shell for protection in ancient times. It lives in shallow tidal pools.
Pokemon Omega Ruby: When its natural enemy attacks, it oozes purple fluid and escapes.
Pokemon Alpha Sapphire: It apparently had a huge shell for protection in ancient times. It lives in shallow tidal pools.
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