The Basic Prehistoric Era is the oldest era known in SpongeBob SquarePants. It appeared in the episode "SB-129," when Squidward accidentally used the time machine to go back home from the 40th Century.
The only known inhabitants are Primitive Sponge, Primitive Star, Jellyfish and Tapeworm. Talking, writing, fire and other conditions where not discovered yet and the biggest invention was jellyfishing which was invented by Squidward Tentacles.
- Basic Prehistoric Era was prior to the Advanced Prehistoric Era.
- The real world era that corresponds with this era is the Cambrian Era.