"Maniraptorans are the most diverse clade of
MANIRAPTORA"Maniraptorans show numerous specializations:
- Elongated forelimb
- Large bony sternum for attachment of the muscles that pull the arms inwards
One possible problematic shared derived feature of Maniraptora is a backwards-pointing pubis. Most coelurosaurs (and saurischians in generally) have a vertically-oriented or anteriorly-oriented pubis. In therizinosauroids, alvarezsaurids, the basal troodontid Sinovenator, dromaeosaurids, Archaeopteryx, and avialians the pubis points backwards; in the basal therizinosaur Falcarius, oviraptorosaurs, and troodontids other than Sinovenator it points vertically or anteriorly. So it is difficult to say which condition is found in the concestor of Maniraptora.
- Semilunate carpal: a pully-shaped block of wrist bone that allowed greater folding motion while sacrificing motion in any other plane
Changes in the muscle attachments in the hindlimbs of maniraptorans show a switch from the femur-and-tail power stroke found in other dinosaurs (inherited from the early diapsids) to one where the flexion of the knee is more important.
Maniraptorans are the most diverse clade of dinosaurs. None
retain[have] a basal theropod form: indeed, very few retain[have] the ancestral carnivorous condition. Major groups include Oviraptorosauria, and Eumaniraptora [Paraves]"
The bottom line is that pterosaurs are very similar to birds while as we see from the quote above, dinosaurs are not similar at all.