Chōmei

The is a demon kabutomushi sealed within Fū from Takigakure. It resembles a gigantic, blue rhinoceros beetle, with six of its seven tails resembling green insect wings, along with the seventh tail, all growing from the end of its abdomen.

Background
According to Madara Uchiha, the Seven-Tails came into being near the end of the waning days of the Sage of the Six Paths' life; to prevent it's resurgence, the Sage split up the demon's chakra of the Ten-Tailed Beast into nine seperate, monsterous constructs of living chakra, which would become known as the 'Tailed Beasts'. It has been captured, extracted, and sealed by Akatsuki.