Onchidiidae

Adult onchidiids lack a shell, although a shell and operculum is present at the larval stage. The mantle cavity is reduced to the point of absence, correlating with a loss of gills, raphes, and other characters usually found in the mantle cavity. The organism is completely detorted. Slugs in this family make and use love darts made of chitin. == Genetics ==

In this family, the number of haploid chromosomes lies between 16 and 20 (according to the values in this table). ==Habitat==

Most of the species in this family are marine and are found in the intertidal zone. Many species live on rocky coasts, while others live in mangrove forests which may be marine or brackish. Semperoncis montana (synonym in literature: Platevindex apoikistes and Semperella montana) and Platevindex ponsonbyi are the only known terrestrial species in the Onchidiidae. They live in high-elevation rainforests in Borneo and the Philippines. ==Life habits==

All these slugs breathe air. The marine ones breathe and move around and feed during low tide, when the water recedes and the slugs are exposed to the air. ==Genera==

Genera in the family Onchidiidae include: • Alionchis Goulding and Dayrat, 2018 • Onchidina Semper, 1885 • Paraoncidium Labbé, 1934: synonym of Onchidina Semper, 1882 • Paraperonia Labbé, 1934: synonym of Peronia Fleming, 1822 • Peronella Mörch, 1863: synonym of Onchidella J.E. Gray, 1850 • Peroniella Starobogatov, 1976 : synonym of Onchidella J. E. Gray, 1850 • Quoya Labbé, 1934: synonym of Peronia J. Fleming, 1822 • Quoyella Starobogatov, 1976: Peronia J. Fleming, 1822 • Scaphis Labbé, 1934: synonym of Peronia J. Fleming, 1822 • Semperella Labbé, 1934 synonym of Semperoncis Starobogatov, 1976 • Watsoniella Hoffmann, 1928: synonym of Hoffmannola Strand, 1932 == References ==