Eumaniraptora

The remainder of non-avian Theropoda, non-avian eumaniraptorans, were more closely related to birds than to the others (Figure 9.32). The group consists of those highly predaceous and intelligent carnivores, Deinonychosauria and Avialae. Deinonychosaurs rightly ought to

Figure 9.30. Left lateral view of the skull and skeleton of Ornitholestes.

Figure 9.30. Left lateral view of the skull and skeleton of Ornitholestes.

50 cm

Ornitholestes
Figure 9.31. The therizinosaur Nothronychus meets its skeleton.

Troodontidae

Troodontidae

Basisphenoid Recess

Dromaeosauridae

Deinonychosauria

Eumaniraptora Maniraptora

Dromaeosauridae

Deinonychosauria

Eumaniraptora Maniraptora

Figure 9.32. Cladogram of Eumaniraptora. Derived characters include: at 1, pneumatic foramen in quadrate, loss of basisphenoid recess, large number of teeth, close packing of front dentary teeth, reduced basal tubera, asymmetrical metatarsus, slender metatarsal II markedly shorter than metatarsals III and IV, and a robust metatarsal IV; at 2, short T-shaped frontals, a caudolateral overhanging shelf of the squamosal, lateral process of quadrate that contacts quadratojugal above enlarged quadrate foramen, stalk-like parapophyses on dorsal vertebrae, modified raptorial digit II, chevrons and prezygapophyses of caudal vertebrae elongated and spanning several vertebrae, presence of subglenoid fossa on coracoid.

evoke more fear and nightmares than T. rex, for they include the sickle-clawed troodontids and dromaeosaurids. And with Avialae, we've come to Aves and its very near relatives: subjects rightly deserving their own chapter (see Chapter 10).

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