Ningchengopterus

In 2009 Lü Junchang named and described a new species of pterosaur, Ningchengopterus liuae, based on a single well-preserved baby skeleton. The skeleton was found in Lower Cretaceous rocks of the Jiufotang Formation in Ningcheng County, Inner Mongolia, China. The specimen was brought to Lü’s attention by Liu Jingyi and is named for her and for Ningcheng County. 

The articulated skeleton is on a part and counterpart slab, and is made up of the skull, nearly complete vertebral column, some ribs, most of the right wing, and most of the right leg, as well as soft tissue from the neck, torso, and wing membrane. The entire slab is only about 15 cm by 6 cm (6 by 3 inches). The skeleton comes from a baby, and was roughly the same size as many living chickadees and nuthatches. 

The skull is almost entirely complete, with its upper surface and left side exposed. It’s long and tapering with a very narrow rostrum. There is a rectangular mass of bone on the upper surface of the skull above the eyes. This may have been a crest, or may be displaced bones of the right side of the skull. Unfortunately, Lü did not describe this feature in his text. Soft tissue made up of parallel fibers directed up and back is seen above the eye. The upper and left side of the lower jaw is visible, and the chin bears a weak midline crest. 

There are 12 pairs of teeth in the upper jaws, and 13 pairs in the lower jaws. They are all sharply pointed, narrow, curving cones. The teeth near the tips of the jaws are longer, thinner, and appear to be directed more laterally than those further back in the jaws. 

The wing bones are well preserved, but poorly ossified, confirming the juvenile age of the specimen. The total wingspan of this individual was about 20-25 cm (8-10 inches), but its adult size cannot yet be known. Lü suspects that it may have been very young, possibly a hatchling. 

When it was first described, Ningchengopterus was not assigned to any pterosaur family, but Lü compared it to several other pterosaurs known from the Jiufotang Formation. He found that its limb bone proportions were most like a ctenochasmatid known as Eosipterus, and similar to ctenochasmatids in general. Lü pointed out that ctenochasmatids generally have hundreds of needle-like teeth lining their jaws, and not just 50. Unfortunately Eosipterus is known from a headless skeleton, so it can’t be known if they were indeed closely related or even the same species. 

Ningchengopterus lived about 120 million years ago in a temperate forest with large numbers of rivers and lakes. The teeth of Ningchengopterus suggest that it might have eaten worms or insects as a baby. Most ctenochasmatids are suspension feeders, using their teeth to strain small prey from mud or water. If Ningchengopterus is indeed a ctenochasmatid, its diet may have transitioned as it grew up.