Preondactylus bufarinii (Wild 1984, Dalla Vecchia 1998; Norian, Late Triassic, ~205 mya) was considered by Unwin (2003) to be the most basal pterosaur. It is not. Derived from a sister to the Italian specimen of Austriadactylus, Preondactylus phylogenetically preceded Dimorphodon.

Distinct from Austriadactylus, the skull of Preondactylus was lower and narrower with a larger antorbital fenestra completely posterior to the naris.

The cervicals were shorter, the caudals more robust.

The scapula and coracoid were more robust and straighter. The sternum was much larger. The humerus was anteriorly concave. The ulna and radius were shorter. The pelvis and pes were relatively longer. Pedal digit IV was shorter and V was longer. The metatarsals were longer than the pedal digits and IV was shorter than III.

Rollover this image of the mold of the skull of Preondactylus to see the bones identified.

Unnamed (Wild 1984) MCSNB 2887 is a partial Triassic pterosaur that nests with Preondactylus. The long cervical ribs mark it as basal.

Calestiventus hanseni (Britt et al. 2018; BYU 20707; Late Triassic) was considered a sister to Dimorphodon originally, but here nests between Preondactylus and Dimorphodon. It was found in desert terrain in Western North America. The orbit is infilled by the jugal.

Britt BB, Dalla Vecchia FM, Chure DJ, Engelmann GF, Whiting MF, and Scheetz RD 2018. Caelestiventus hanseni gen. et sp. nov. extends the desert-dwelling pterosaur record back 65 million years. Nature Ecology & Evolution. doi:10.1038/s41559-018-0627-y.

Dalla Vecchia FM 1998. New observations on the osteology and taxonomic status of Preondactylus buffarinii Wild, 1984 (Reptilia, Pterosauria), Boll. Soc. Paleont. It., 36(3, 1997): 355-366

Wild R 1984. A new pterosaur (Reptilia, Pterosauria) from the Upper Triassic (Norian) of Friuli, Italy, Gortiana — Atti Museo Friuliano di Storia Naturale 5:45-62.

wiki/Preondactylus