Elysium, a section of the underworld containing the Elysian Fields
Elysia bangtawaensis was first found in mangrove swamps in southern Thailand, but has since also been identified in eastern Australia and Goa.
Elysia serca also bears great similarities to Elysia catulus (Gould, 1870), a species with a more northerly distribution, and Jensen (1983) considers that E. serca may be a subspecies or ecotype of E. catulus.