Revision of Romanian sauropod dinosaurs reveals high titanosaur diversity and body-size disparity on the latest Cretaceous Haţeg Island, with implications for titanosaurian biogeography

Journal of Systematic Palaeontology, Journal Year: 2025, Volume and Issue: 23(1)

Published: Feb. 20, 2025

The Hațeg Basin and surrounding areas in Transylvania, western Romania, have been a hotspot for research on vertebrate faunas of the Late Cretaceous European Archipelago. One historically earliest titanosaurian sauropod dinosaurs to be discovered, 'dwarfed' species Magyarosaurus dacus comes from lower Maastrichtian deposits this basin; however, has neglected, with no modern treatment its anatomy, taxonomy or phylogenetic affinities. Via detailed anatomical study historical undescribed remains, combined archival data, we identify shared autapomorphies that link multiple partial skeletons. Our analysis hundreds specimens (including >20 monospecific assemblages) enables stabilization type dacus. We propose presence three additional, but only partly contemporaneous taxa – Paludititan nalatzensis, Petrustitan ('Magyarosaurus') hungaricus n. gen. Uriash kadici sp. (the latter being amongst largest known sauropods Archipelago). present new (152 scored 570 characters), implications broader evolutionary relationships biogeography: is recovered either as member close relative Saltasauridae; affinities Lognkosauria, along Lohuecotitan; most closely related South American early diverging eutitanosaurian taxa; also shares Gondwanan taxa. findings strengthen hypothesis latest titanosaurs belonged lineages invaded former area during Barremian–Albian. interpret body-size disparity evidence large-bodied were ecologically excluded reduction by competition small-bodied titanosaurs, dwarfing occurred stratigraphically earlier among several Island are descendants existing dwarfed ancestors. Finally, find indication body size-related turnover uppermost Transylvanian area.

Language: Английский

The re-description of Liaoningotitan sinensis Zhou et al., 2018

PeerJ, Journal Year: 2025, Volume and Issue: 13, P. e19154 - e19154

Published: March 11, 2025

Liaoningotitan sinensis is one of three sauropod species found in the Jehol Biota. from Lower Cretaceous Yixian Formation Liaoning, China. The discovery was an important breakthrough for researching diversity giant herbivorous animals However, research and analysis are not yet complete. This study presents a comprehensive holotype. First, skull, vertebrae, pelvic girdle, appendicular elements holotype were carefully reexamined, leading to mosaic evolution occurring skull identification new autapomorphy humerus : attachment point coracobrachialis muscle on anterior surface proximal end flat. Second, characteristics other well-preserved dinosaurs used reconstruct . Next, Euhelopus zdanskyi body type holotype, result indicating that approximately 10 m length. Finally, TNT software utilized analyze phylogenetic position , with can be classified into Euhelopodidae.

Language: Английский