Figure 1. The ancestry of Scleromochlus going back to Lewisuchus, Saltoposuchus, Terrestrisuchus, SMNS 12591 and Gracilisuchus, which appears to be the chubby, short-legged, secondarily quadrupedal one.
Once miniaturization and bipedal locomotion appeared in a sister to Lewisuchus (Fig. 1), evolution provided a variety of bipeds in basal archosaurs in a variety of sizes. These (Fig. 1) represent one such clade. Another clade derived from a sister to Lewisuchus produced poposaurs. Yet another produced, Litargosuchus, Dibothrosuchus and extant crocodilians. Still another produced Pseudhesperosuchus and basal dinos.
The large reptile tree is now up to 460+ taxa, still working with the same 228 character list.
The Pterosaur Heresies 