|Holotype IGM 100/1127|
Clark, Norell & Barsbold, 2001
Clark, Norell, & Barsbold, 2001
Khaan did not differ much from other oviraptorids. At first, its remains were assigned to "Ingenia", but the Khaan manual structure, lacking the expansion of the upper third metacarpal, was considered to differ sufficiently from that of "Ingenia" for it to be assigned to its own genus.
The oviraptorid diet is disputed, with plants and molluscs having been suggested. Like other oviraptorids, Khaan was probably at least partially a meat eater, feeding on small vertebrates like mammals, lizards and possibly other small dinosaurs. It was also probably feathered.
The type species Khaan mckennai was in 2001 named by James M. Clark e.a. The genus name is derived from Mongol khaan, "lord" or "ruler". The specific name honours the paleontologist Malcolm Carnegie McKenna.
The holotype IGM 100/1127, consists of an almost complete skeleton found together with another specimen, IGM 100/1002. Together they were informally referred to as "Romeo and Juliet". These individuals are about four feet long. A third, considerably larger, specimen, IGM 100/973, was referred to the species.
According to a 2014 study published in Nature, Khaan was possibly sexually dimorphic. Two specimens, the holotype MPC-D 100/1127 and referred specimen MPC-D 100/1002, were analyzed, the dimorphic feature being in the anterior chevrons. Both specimens were of the same size and build, and thus were likely the same age, ruling out ontogeny. In MPC-D 100/1127, the anterior chevrons showed great similarity to those of other theropods, with no great expansion on the distal end. However, in the other individual, the chevrons had a "heel"-like expansion above the distal end, which increased in size along the sequence. The study ruled out a possibly pathologic explanation, finding sexual dimorphism to have more support. It was thought that the reduced spines were a female characteristic, because they would increase space for laying eggs. Also, the larger spines could be for male muscle attachments, which would support a tail fan.