According to Federation archaeologist Miliani Langford, the B'nurlac civilization was destroyed when their bioengineered slave races rose up to eradicate them. The B'nurlac were described as having low, ankylosaurian bodies with bony dorsal carapaces and clubbed tails. They built at least some of their civilization on top of ancient Manraloth ruins, such as those found on a planet that was known eons later as Tanebor.