It is estimated to be 3.7-million years old.
The stunning discovery, unearthed in Kenya's Sofnfree Crater, will challenge many long-held beliefs about when the first hominids developed hair extensions.
According to lead researcher Dr Darwin Chirwa, the find included the complete skull of a young female sporting long extensions, apparently made from the tail of a prehistoric species of mega-horse, Equus Nylons.
"Half her head is still in cornrows, so it seems that she was only halfway through the 14-hour weave ordeal when she and her hairdresser had their appointment cut short by a tidal wave of lava from a nearby volcano," he said.
"Being doused in molten rock was probably a blessed relief."
Chirwa said that there was probably huge social pressure on hominid females to have straight hair.
"Which was incredibly unfair, given that both males and females were covered in luxuriant hair from head to toe."
Meanwhile, a number of porcupine quills found on the site have led to speculation that quills may have been glued on to female eyelids and used as prehistoric false eyelashes.
"The effect would have been very striking," said Chirwa.
"But also startlingly bloody if they leaned in to kiss a mate."