August 31 , 2016

The association between Megaloolithus cf. siruguei eggs and hadrosaurid (Telmatosaurus transsylvanicus) hatchlings that was reported 25 years ago in Maastrichtian mudstone from Tustea (Hateg Basin, Romania) is reviewed in this paper. Subsequent to the original descriptions of this association, eggshell micro- and ultrastructure have been compared with M. siruguei from northern Spain and southern France which allowed a safe assignment of the Tustea eggs to this oospecies. Although the eggshell correspondence with M. siruguei from southern Europe is well-sustained by microstructural features, SEM analysis of the Tustea eggs has revealed Y-shaped pore canals, now considered diagnostic to Megaloolithus patagonicus. Thus, in addition, the controversial embryonic tooth, associated with undetermined incompletely calcified remains inside a broken egg from Tustea, not clearly presented before is discussed here as a conclusive proof allowing the referral of the M.siruguei eggs from Tustea to Telmatosaurus transsylvanicus. Some taphonomic aspects related to the eggs hatchling are interpreted on the basis of high-resolution computed tomography images.

Dan Grigorescu (2016)
The ‘Tustea puzzle’ revisited: Late Cretaceous (Maastrichtian) Megaloolithus eggs associated with Telmatosaurus hatchlings in the Hateg Basin.
Historical Biology (advance online publication)
doi: http://dx.doi.org/10.1080/08912963.2016.1227327