Possibly the craziest headgear of all known pterosaurs.
Nyctosaurus was a relative of the well-known Pteranodon, living alongside its more famous cousin around the southern reaches of the Western Interior Seaway about 85 million years ago. It had a wingspan of around 2m (6.6ft), and was overall about the size of a seagull.
That bizarre antler-like crest wasn’t discovered until the early 2000s — all previously known skulls had been badly crushed or belonged to crestless juveniles. Although some reconstructions put a huge sail-like membrane of skin over the crest, there’s no evidence for any soft-tissue attachment points on the bones.
Another unique feature of Nyctosaurus is its complete lack of fingers, aside from the main flight digit. Most pterosaurs are thought to have used their clawed fingers for grip when walking around on the ground, and it’s possible that Nyctosaurus lost its fingers simply because it’s lifestyle meant it didn’t need them. Much like modern albatrosses, it might have spent almost all of its time at sea and only rarely returned to land.