Huaxiapterus benxiensis (Lü et al. 2007, Early Cretaceous, BXGM V 0011, aka Sinopterus benxiensis) is a small crested pterosaurs that nests at the base of the Tapejaridae in the LPT. This species has a gracile humerus, robust hind limbs and shorter distal wing segments, hinting at a borderline flightless incapability.

Sinopterus dongi IVPP V13363 (Wang and Zhou 2003) wingspan 1.2 m, 17 cm skull length, was linked to Tapejara upon its discovery. Derived from a sister to tiny Nemicolopterus, Sinopterus phylogenetically preceded Huaxipterus.

Much larger than and distinct from Nemicolopterus, the skull of Sinopterus had a convex dorsal profile created by an expanding antorbital fenestra. The lacrimal and nasal were greatly expanded. The frontal and parietal were reduced, as in Shenzhoupterus. The jugal was more robust, but the orbit remained large. The mandible was deeper, as in Shenzhoupterus. The palate was twice as wide.

The sacrals were nearly one half of the torso, as in Shenzhoupterus, but the torso remained more elongated, as in Nemicolopterus.

The sternal complex was pentagonal. The radius and ulna were elongated. Manual 3.1 was longer than m2.1. Manual 4.1 was longer than the metacarpus. Manual 4.2 extended past the elbow.

Metatarsal III was the longest. The proximal pedal phalanges were elongated such that p1.1 was subequal to p2.1 and p3.1.

The family tree of the Ornithocephalia and Germanodactylia is here. The expanded family tree of the Pterosauria is here.