strongly appending beak. Of the conical premaxillary teeth, the first is the largest. The maxilla bears eighteen teeth. The eye socket is surrounded by the lacrimal, a single supraorbital and a large postorbital, excluding the prefrontal and the jugal from the orbital rim. The postcranial skeleton was in 2001 not described in any detail. The skulls, though of large and thus not juvenile individuals, do not show a distinctive pattern of fused caputegulae, head tiles. This inspired Carpenter to propose an alternative hypothesis of ankylosaur skull osteoderm formation. Formerly, it had been assumed that such armour plates were either formed by direct skin ossification into distinct scutes which later fused to the skull (the more popular theory), or by a reaction of the skull bones to the pattern of overlying scales. The lack of a clear pattern in Cedarpelta suggested to Carpenter that the ossification took place in an intermediate layer between the scales and the skull roof itself, which he surmised to have been the periosteum. Classification Carpenter (2001) placed Cedarpelta within the family Ankylosauridae and offered two interpretations of its position. The first was that it could be the basalmost known ankylosaurid, i.e. the first discovered branch to split off from the ankylosaurid stem line. This would be in line with its plesiomorphic traits and the fact that the in 2001 supposed Barremian age made it one of the oldest known ankylosaurids. The second was that it formed an early ankylosaurid branch, or clade, Shamosaurinae together with Gobisaurus of north-central China and the eponymous Shamosaurus of Mongolia. Thompson et al. (2012), Chen et al. (2013), Yang et al. (2013), Han et al. (2014), Arbour & Currie (2015), Arbour et al. (2016), Arbour & Evans (2017), Yang et al. (2017), Zheng et al. (2018), Rivera-Sylva et al. (2018), Park et al. (2019) and Frauenfelder et al. (2022) have all found Cedarpelta to be within Ankylosauridae, as either within a polytomy with Liaoningosaurus, Aletopelta, Chuanqilong, Gobisaurus and Shamosaurus or as sister taxon to Chuanqilong. The results of Arbour & Currie (2015) are reproduced below. Vickaryous et al. (2004) interpreted Cedarpelta as the basalmost member of the family Nodosauridae, positioned even below the nodosaurids Pawpawsaurus, Silvisaurus, and Sauropelta. Wiersma & Irmis (2018) also interpreted Cedarpelta as a nodosaurid. The results of Vickaryous et al. (2004) are reproduced below. See also Timeline of ankylosaur research References Early Cretaceous dinosaurs of North America