The stratigraphically oldest remains of ornithomimid theropod dinosaurs are known from the
Cenomanian Khodzhakul Formation and the Turonian Bissekty Formation of Uzbekistan.
The ornithomimid from the Bissekty Formation is documented by more than 800 isolated
bones that represent much of the skeleton. It shows at least three unambiguous
synapomorphies of Ornithomimidae: length of anterior cervical centra three to five times
greater than transverse width; low and rounded fibular crest of tibia; metatarsal III pinched …

The oviraptorosaurian theropod Caenagnathasia martinsoni is the least common dinosaur
taxon in the Late Cretaceous (Turonian) vertebrate assemblage from the Bissekty Formation
of the Kyzylkum Desert, Uzbekistan. The dentaries show numerous caenagnathid
synapomorphies, including a fused dentary symphysis bearing distinct vascular grooves and
associated foramina on its lingual surface, a lingual triturating shelf on the dentary, and
extensive pneumatization of the dentary. Cervical and dorsal vertebrae attributed to C …