Osteology of Zalmoxes shqiperorum (Dinosauria, Ornithopoda), based on new specimens from the Upper Cretaceous of Nalat-Vad (Romania)

Nălaţ-Vad is a new fossil locality discovered in 2002 in the Sănpetru Formation (Maastrichtian, Late Cretaceous) of the Haţeg Basin (Transylvania, Romania). This site has, among others, yielded the most complete skeleton that can be referred to the ornithopods dinosaur Zalmoxes shqiperorum Weishampel, Jianu, Cziki & Norman, 2003, but also isolated elements belonging to both juveniles and adult individuals. This material provides new information about the anatomy of Z. shqiperorum, and about the inter- and intraspecific variability within Zalmoxes. Zalmoxes robustus (Nopsca, 1902) and Z. shqiperorum were apparently sympatric species in Transylvania by latest Cretaceous time. The co-existence in the same locality of two closely-related species is not an isolated case among ornithopod dinosaurs.