The only described species, Kakuru kujani, is known primarily from evidence of a single tibia, which had been fossilised through a rare process in which the bone through hydration turned to opal.

The opalised tibia was exhibited by a gem shop in 1973 and by chance brought to the attention of paleontologist Neville Pledge.

The owner at the time, a certain A. Fleming, allowed pictures and two casts to be made but eventually the specimen was sold at an auction to an anonymous buyer.

It is very slender in build and shows the impression of the ascending process of the astragalus, an ankle bone itself lost.

Two separate analyses in 2010 found the holotype tibia of Kakuru to have no distinguishing characteristics and could only be confidently placed in either Averostra or Tetanurae.