Nurhachius ignaciobritoi (Wang, Kellner, Zhou & Campos 2005) IVPP V-13288, Early Cretaceous, skull length ~30 cm, ~2.5 m wingspan, was derived from a sister to Coloborhynchus, and Criorhynchus. Nurhachius was a phylogenetic predecessor to SMNK PAL 1136 and Istiodactylus.
Distinct from Criorhynchus the skull of Nurhachius further extended the rostrum and increased the size of the antorbital fenestra. If predecessors had a crest, it was greatly reduced or underdeveloped in Nurhachius. The orbit was very narrow and posteriorly slanted with a tiny sclerotic ring at the top. The upper temporal fenestra was completely above the orbit.
Distinct from Coloborhynchus, the sternal keel was very deep (if that is the keel). The humerus was shorter. Fingers I-III were smaller.
The femur was shorter. The metatarsals were robust and the pedal digits were slender, as in Zhenyuanopterus.
The ornithocheirid family tree is here. The entire pterosaur family tree is here.