What is "atollidae"

Atollidae is a family of jellyfish, in the Coronatae order. The family consists of only one genus, Atolla (Haeckel 1880). The Atolla genus was originally proposed by Haeckel in 1880 and elevated to the family level by Henry Bigelow in 1913.

Atolla is a genus of crown jellyfish. The six known species inhabit the mesopelagic zone. The medusae possess multiple lobes called lappets at the bell margin. Medusae also have eight tentacles, alternating with eight rhopalia, and there are twice as many lappets as tentacles.