Euhadra peliomphala

Euhadra peliomphala is a species of air-breathing land snail, a terrestrial pulmonate gastropod mollusk in the family Bradybaenidae. This species is endemic to Japan. The species exhibits exceptional geographical variation in its mitochondrial DNA. Euhadra peliomphala has 4 subspecies: As Euhadra peliomphala matures sexually, it develops a 'head-wart' between the optic tentacles. The development of the 'head-wart' parallels the development of the snail's reproductive system. The 'head-wart' releases the steroid hormone, testosterone, throughout the body before mating.