Scientists say it is a unique ecosystem that has been cut off from the world for five million years and that other ancient life forms may be living there as well.
Dr Hanan Dimantman, a biologist at the Hebrew University of Jerusalem, said," We are sure that the eight species that were found are only the beginning of the story of this ecosystem."
The cave connects to a lake and a network of passageways that extend for more than a mile (1.6km) some 400ft (120m) underground and it is thought to date back millions of years to a time when the area was part of the Mediterranean Sea.
Two of the animals live in seawater and two others live in fresh or brackish water, which means they may be descended from ancient sea creatures, the scientists say.
All of the newly discovered species were found alive, except for one type of blind scorpion.
Specimens have been sent to European and Israeli experts in order that the creatures can be named and classified.
