A Catalog of Zalmoxes (Dinosauria: Ornithopoda) Specimens from the Upper Cretaceous Nălaţ-Vad Locality, Haţeg Basin, Romania

ABSTRACT The Transylvanian area of Romania boasts a rich fossil record of dinosaurs, which lived on an island (Haţeg Island) during the very end of the Cretaceous. Many of these are dwarfed in body size or exhibit other unusual features thought to be linked to their insular habitat. One of the most common of these dinosaurs is the rhabdodontid ornithopod Zalmoxes, an herbivorous taxon that has been found at many Upper Cretaceous sites across Transylvania. Our collaborative fieldwork has uncovered several new Zalmoxes specimens from the Nălaţ-Vad (= Vadu) locality, a site along the Râul Mare River in the Haţeg Basin that dates to the “middle” to late Maastrichtian. These include a partial associated skeleton, along with various isolated bones from several additional individuals. We catalog and describe these specimens here, and compare them to other Zalmoxes fossils from Romania. They provide further evidence that Zalmoxes was one of the most common vertebrates in the latest Cretaceous of Transylvania, and add to the unusual fossil record of Nălaţ-Vad, which has yielded a much greater number of associated skeletons than other Transylvanian localities. Some of the Nălaţ-Vad specimens possess features characteristic of the type species, Z. robustus, whereas others exhibit features diagnostic of the larger and stockier Z. shqiperorum, indicating that these species were locally sympatric, as has been demonstrated at other Transylvanian sites. The specimens span much of the size range known from Zalmoxes, as well as the spatial and temporal extent of the Nălaţ-Vad locality, suggesting that this taxon flourished until near the end of the Cretaceous.

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