Skeeter

Skeeters are giant pond skater-like bugs that float on top of the water that are first introduced in Super Mario 64. They appear in several 3D Mario games, each with their appearance changed. Skeeters can also walk on land as well as skate on water. Skeeters are based off a real-world insect known as the water strider.

Super Mario 64 / Super Mario 64 DS
In Super Mario 64, one is seen on the painting of Wet-Dry World and also are enemies floating aimlessly on the water in Wet-Dry World. They look like big blue-green pond skaters with plate webbings on their feet and antennae on their backs. If defeated, they release three Coins. In Wet-Dry World, they can be lowered onto a platform. When they see Mario, they will get mad for him taking them off the water, and will try to home in on him.

In Super Mario 64 DS, Skeeters are found in the same places as in Super Mario 64, but are blue with yellow-tipped legs, the angler on their head is red instead of orange, and they have black eyes here. Five of these enemies also appear in Dire, Dire Docks, a course in which they were absent in the original version. Three Coins are again released for their death. Again, they will only home in on the heroes if they are lowered onto land.

Super Mario Sunshine
Skeeters reappear in Super Mario Sunshine, where they are referred to as Pondskaters. They are found in Bianco Hills. When jumped on, Mario propels upward to a height rivaling the Rocket Nozzle. They are also resistant to F.L.U.D.D., as spraying them only makes them stop moving for a very short while. The only way to defeat them is to bring a Yoshi onto a lilypad and eat them.

Super Mario Galaxy 2
Despite not appearing in the previous game, Skeeters reappear in Super Mario Galaxy 2, with an overhauled appearance. They now have a flat, purple body without an antenna and are found in the Cosmic Cove Galaxy. They always home in on Mario, and can be stomped for a Coin or hit with a spin to release three Star Bits. They also appear in Starshine Beach Galaxy and Throwback Galaxy.

Mario Party 3
In Mario Party 3, a completely static Skeeter can be seen in the background of Woody Woods.

Trivia

 * In all four Super Mario series games they appear in, including Super Mario 64 DS, Skeeters have had a distinctly different design.