Huh. Today I learned. I should keep a look out for that type of stuff now...
I think Don't Starve pulled off something similar, where in the last area, reading the gravestones give you the credits of the development team. I say "Think" because Don't Starve is rather difficult and I never actually got around to beating Adventure Mode.
And I can't help myself. Here's some more Pokemon, some you might know.
[SPOILER="More Regalo Del'Mar Pokemon"]
Omanyte
Goomy, Sliggoo, and Goodra
Clauncher and Clawitzer
Skrelp and Dragalge
Spritzee
Durant
Shelmet
Frillish and Jellicent (Blue are males, Pink are Females)
Vulpix
Tympole, Palpitoad, and Seismitoad
Servine and Serperior
Tangela and Tangrowth
Shellos (There are two variations: East sea and West sea respectively)
Weedle, Kakuna, and Beedrill
Combee and Vespiquen
Spinarak
Wooper and Quagsire
I imagine most of these would lurk in swamps or estuaries deep in Regalo Del'Mar. Seismitoad and its relatives would've driven the Poliwag line out of these areas, as they evolve via level up rather than Water Stone, and inversely Spinarak are seldom seen thanks to the Galvantula and Joltik population taking most of the available prey, and so on.
[/SPOILER]
...I may of gotten carried away there. Oh well, I'm sure some of them could apply.
Though maybe I messed up on the Goodra line, considering that line is based on french snails...ah, it's Pokemon, logic doesn't always apply 