TURF: Caves, Sky.
CLOSE RELATIVES: Buzzy Beetle, Giant Parabuzzy.
SKILLS AND ATTACKS: Aerial Ace.
STRENGTHS: It can't be hammered when it's standing upright.
WEAKNESSES: It can be flipped over like a Troopa.
Basically these are flying Buzzies. They love the stench of caves and the fly around. When threatened, they use the attack Aerial Ace, or they just hide in their shell. They tend to snack on sewer water and small fish.
Parabuzzies are generally peace-loving and have even been used to travel through the air, but when threatened they're very fierce.
In Super Mario Bros. 3 Parabuzzies were red-shelled and Mario could hop along them like platforms. They kept their feet hidden in their shells.
They disappeared for quite some time until reappearing in Paper Mario: TTYD where they were dark blue and it was easy to make out their feet. They look similar in Super Paper Mario.