Lohmann, 1892
Trunk depressed dorso-ventrally (Folia gracilis). Mouth terminal. Buccal glands present. Spiracles small and round, at both sides of the rectum. Esophagus entering the stomach from behind or from the right side. Stomach undivided, on the left side of the trunk. Intestine curved, arising from the lower fore part of the stomach. Subchordal cells present.
Bückmann and Kapp (1975) recognized two species: Folia gracilis and Folia mediterranea, the latter found exclusively in the Mediterranean and Oman Seas. However, Lohmann and Hentschel (1939) cited both species from the South Atlantic Ocean, the latter as Oikopleura mediterranea.
Remark
The genera Chunopleura, Folia, Inopinata, Megalocercus, Mesoikopleura, Mesopelagica, Oikopleura, and Stegosoma are grouped together under the supergenus Labiata Fenaux, 1993.