Eurazhdarcho

The Maastrichtian deposits in the Hateg Basin of what is now Romania have preserved a unique latest Cretaceous island world. At the time, around 69 million years ago, the Tethys Ocean had flooded much of Europe and turned it into a great archipelago. 

Some of the islands here were about as large as Madagascar, or larger like the Ibero-Occitan Island made of parts of Spain and France. Then there was the more famous Hateg Island, now a household name among paleo-fans online. 

Here, pygmy non-avian dinosaur herbivores and primitive avians lived alongside highly predatory, robust azhdarchids. Among the largest plant-eaters here were small sauropods like Magyarosaurus, a titanosaur the size of a large horse and the much bigger erect-necked Paludititan. Here, azhdarchids were at the top of the food chain.

Three of them are known from Hateg. 

The smallest is an animal called Eurazhdarcho. Its wingspan was no more than 3 meters across but it was still a good-sized hunter or smaller animals. It would have resembled the rest of its kind, with a large head, small body and short wings. 

However, the Romanian azhdarchids were more heavily-built than their relatives elsewhere and this robustness probably indicates that they were efficient hunters of somewhat larger prey. The only known species in the genus is E. lagendorfensis. 

It was named in 2013 by a team comprising Alexander Kellner, Darren Naish, Gareth Dyke and Matyas Vremir. Vremir discovered the holotype in 2009 in part of the Sebes Formation. It was a series of neck vertebrae and forelimb elements, including the hand and lower arm bones. 

The other pterosaurs here include another medium-sized animal with an even shorter neck-by azhdarchid standards it has barely any neck at all-and the massive Hatzegopteryx with a 10-meter wingspan. This animal was also recently discovered to have been a short-necked genus like its associates. 

The great size differences probably served as niche partitioning among the three genera. This seems to be a trend in several Maastrichtian pterosaur faunas, with a massive genus coexisting with one or two smaller genera. 

The pattern is repeated in faunas as distinct as the Javelina in Texas, home of the original giant pterosaur Quetzalcoatlus (gigantic Q. northropi and smaller Q. sp and most likely another as yet unnamed azhdarchid genus) and earlier North American formations.