New remains of Hungarosaurus tormai (Ankylosauria, Dinosauria) from the Upper Cretaceous of Hungary: skeletal reconstruction and body mass estimation

Abstract

Hungarosaurus tormai is a medium-sized nodosaurid ankylosaur that was described on the basis of four partial skeletons from the Santonian (Upper Cretaceous) of Hungary. In this paper, a new fifth skeleton and several isolated remains are described which greatly improve our knowledge of this primitive nodosaurid ankylosaur. Isolated cranial remains referred to juvenile individuals provide new information on the development of cranial ornamentation in nodosaurid ankylosaurs. Apart from both preserved mandibles with in situ dentition, the fifth partial skeleton contains several previously unknown limb elements (humerus, ulnae, radius) that indicate unusual limb proportions for Hungarosaurus compared with other ankylosaurs. On the basis of the five partial skeletons and the isolated remains, a skeletal and dermal armor reconstruction is attempted. Body mass calculations using three different methods yield an estimate of 650 kg for H. tormai.

Collection of the thinnest: A unique eggshell assemblage from the Late Cretaceous vertebrate locality of Iharkút (Hungary)

“…The absence of thick eggshells cannot result from a negative bias in their fossilization potential, nor can it be explained by sorting in the depositional environment (Botfalvai et al 2015(Botfalvai et al , 2016. Even though the currently known terrestrial amniote fauna of Iharkút is composed of small to medium-sized animals (≤650 kg; Ősi and Makádi 2009;Ősi et al 2012a) which may relate to island conditions (but see Ősi et al 2012b), reasonable egg size estimation for the larger non-avian dinosaur taxa (all ornithischians, abelisaurid, and tetanuran theropods) well exceeds the egg size estimated for the thickest recovered eggshells. Hence, it is highly likely that these taxa laid their presumably much larger eggs in areas farther away from the river system which otherwise could have collected and deposited their eggshells.…”

The first known chamopsiid lizard (Squamata) from the Upper Cretaceous of Europe (Csehbánya Formation; Hungary, Bakony Mts)

“…1), was discovered in 2000. Since that time, it has yielded remains of lepisosteid and pycnodontiform fishes (Ősi et al, 2012b), albanerpetontid and anuran amphibians Venczel, 2010, 2012;Szentesi et al, 2013), bothremydid turtles (Rabi et al, 2012), the first known freshwater mosasaur Pannoniasaurus (Makádi et al, 2012), alligatoroid, ziphosuchian and heterodont eusuchian crocodiles (Ősi et al, 2007; Ősi et al, 2012b), azhdarchid pterosaurs (Ősi et al, 2005), a rhabdodontid ornithopod (Ősi et al, 2012a), the ceratopsian dinosaur Ajkaceratops (Ősi et al, 2010b), the basal nodosaurid ankylosaur Hungarosaurus (Ősi, 2005;Ősi and Makádi, 2009), theropods (Ősi et al, 2010a), and enantiornithine birds (Dyke and Ősi, 2010) as well as well-preserved remains of lizards (Makádi, 2006(Makádi, , 2007Ősi et al, 2012b).…”

A new polyglyphanodontine lizard (Squamata: Borioteiioidea) from the Late Cretaceous Iharkút locality (Santonian, Hungary)

“…Within this long fossil record, terrestrial lizards from the Late Cretaceous western Tethyan archipelago of Europe are also represented by finds from several localities. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 (Ősi et al, 2010), the basal nodosaurid ankylosaur Hungarosaurus (Ősi, 2005;Ősi and Makádi, 2009), theropods (Ősi et al, 2010), and enantiornithine birds (Dyke and Ősi, 2010) …”