Kimberella quadrata
Ediacaran
Late Precambrian (Vendian)
Penega Formation
East Angelsk, White Sea, Russia

35mm on 150mm slab. Large for this species.

Kimberella is a genus of early, bilaterally-symmetrical animal originally described from the Ediacara Hills, southern Australia as a jellyfish, then later reinterpreted as a box jelly.  Since then, numerous well-preserved specimens from the White Sea, northern Russia have led researchers to conclude that may be more closely-related to molluscs (something like a primitive slug).

The Vendian Period spans about the last 110 million years of the Proterozoic Eon from about 540 to 650 million years ago.  It is during this time that soft-bodied, macroscopic life appeared.  By the end of the Vendian the supercontinent, Rodinia, which formed from the collisions of the major land masses approximately 1.2 billion years ago, had started to fragment into continents that would reconnect at the end of the Paleozoic Era over 300 million years later.