Noki

The Nokis are a race of short creatures with shells, first debut in Super Mario Sunshine. They, along with Piantas, inhabit Isle Delfino. They thrive primarily in Noki Bay, many of the Nokis resided rarely rise to the surface of the bay, but rather inhabit in a large underwater area located directly beneath the bay's large waterfall. They are some of the most relaxed and intelligent characters in the Mario series.

Their profile in Mario Superstar Baseball reveals that Nokis evolved from shellfish.

Super Mario Sunshine
The Nokis first appear in Super Mario Sunshine, they inhabit on Isle Delfino with the Piantas. Their primary home on the island is Noki Bay. While they inhabit on Noki Bay, the Nokis appear in other areas of Isle Delfino. Most of the Nokis seen in Pinna Park wear clam like shells instead of hermit shells. In Episode 8 of Noki Bay, many Nokis are seen floating on jellyfish, this implies that Nokis are capable of surviving in underwater habitats, with little or no air available.

Unlike Piantas, Nokis appear to be more trusting of Mario and more aware that he's not the real criminal. In Noki Bay, the Noki Elder often aids Mario by instructing him on how best to go about his tasks. He also helps Mario by training him to use a deep sea helmet so that he can fight Eely-Mouth in Noki Bay, and later reap the rewards of the Red Coin Fish.

Mario Kart: Double Dash!!
Nokis made a small appearance in Mario Kart: Double Dash!! in Peach Beach and the ending ceremonies.

Mario Tennis series
Nokis along with the Piantas appear as audience and spectators in Peach Dome court of Mario Power Tennis for the Nintendo GameCube and Mario Tennis: Power Tour for the Game Boy Advance.

Mario Baseball series
Nokis are playable in Mario Superstar Baseball and Mario Super Sluggers. The playable Nokis in these games were all females. The player can also change the color of the Nokis.

Mario Strikers series
Nokis once again appear in the audience in Super Mario Strikers and its sequel, Mario Strikers Charged.

Super Mario Sunshine description
''Nokis wear vibrant seashells reminiscent of their time living in the coral reefs. They are timid but highly intellectual.''

Super Smash Bros. Brawl sticker
A sticker of a Noki can be obtained in Super Smash Bros. Brawl. In the Subspace Emissary, the Noki sticker increases the power of leg attacks by twelve.

Collectible Card Info
Another resident of Isle Delfino who befriended Mario on his ill-fated tropical vacation, Blue Noki isn't a power player on the baseball field, but can put a wicked curve on his changeup.

Trivia

 * In Pinna Park the Noki playing the Conch Shell plays the first six notes of the Super Mario Bros. overworld theme.
 * In Mario Super Sluggers, characters mistakenly use male pronouns for the playable female Nokis.
 * The word "Noki" translates to "shell" in English, which is what a Noki wears.
 * In Mario Super Sluggers, while the Piantas share good chemistry with the Toads and Toadsworth, the Nokis have good chemistry with Toadette, whose chemistry is neutral with the Piantas. In a similar manner, the Toads and Toadsworth have neutral chemistry with the Nokis.