Morphometry, Microstructure, and Wear Pattern of Neornithischian Dinosaur Teeth From the Upper Cretaceous Iharkút Locality (Hungary)

Abstract

Teeth of iguanodontian ornithopods and ceratopsians could be remarkably similar, thus the referral of isolated dental material to particular neornithischian clades can be highly problematic. These groups are represented by the rhabdodontid Mochlodon vorosi and the basal coronosaurian Ajkaceratops kozmai in the Upper Cretaceous Csehbánya Formation at Iharkút (western Hungary). Whereas teeth of the former taxonMochlodon are common elements at the locality, no dental material belonging to the latter speciesAjkaceratops was identified until now. Here we used mathematical statistical approaches, as well as tooth wear and dental microstructure analysis in order to decide whether the teeth previously referred to Mochlodon can be treated as a homogenous sample, or some remains belong rather to Ajkaceratops.According to our results, there was a striking morphological and structural convergence between the teeth of the latterboth taxa. However, the wear study revealed the existence of two different patterns within the sample. One is characterized by straight and parallel microstriations that suggest orthal movements during the jaw closure. This pattern was associated with Mochlodon. The other pattern appeared only on a few teeth, and it can be differentiated by its distinctive curved microstriations that indicate circumpalinal chewinga significant palinal component. Since Because curved striations were have never been described in ornithopods, but were are found in several neoceratopsians, this pattern was associated here with Ajkaceratops. Here we present the first teeth that can provisionally be referred to the latter genus. We believe that the methodology discussed in this paper will facilitate distinguishing ceratopsian and ornithopod teeth in other localities as well.

A new microvertebrate assemblage from the Mussentuchit Member, Cedar Mountain Formation: insights into the paleobiodiversity and paleobiogeography of early Late Cretaceous ecosystems in western North America

“…12H – 12L ) is a small, triangular tooth with a CH of 1.4 mm, a FABL of 1.49 mm, and a BW of 0.79 mm, possibly pertaining to Neornithischia, Ankylosauria, or Pachycephalosauria. It has seven cusps, a typical characteristic of premaxillary teeth of basal euornithopods ( Oreska, Carrano & Dzikiewicz, 2013 ), and lacks an elevated rim along with the primary and secondary ridges present in ornithopod teeth such as Zalmoxes ( Virág & Ősi, 2017 ).…”

Exceptionally simple, rapidly replaced teeth in sauropod dinosaurs demonstrate a novel evolutionary strategy for herbivory in Late Jurassic ecosystems

“…Despite nearly two centuries of study and the discovery of novel tooth forms, our understanding of dinosaur dietary ecologies remains limited compared to other groups, such as mammals [1,2]. Much of what is known relies on osteological comparisons to extant analogues, frequently noted in early discoveries [3], microwear analyses [2,[4][5][6][7][8][9], and the rare preservation of stomach contents [10][11][12][13][14]. The few studies that have applied quantitative methods to the study Open Access of dinosaur dentitions have yielded tantalizing insights.…”

Dental microwear texture reflects dietary tendencies in extant Lepidosauria despite their limited use of oral food processing

“…[24,25]) were long restricted to large herbivorous mammals [13,22,26] and extant and extinct primates as well as for reconstruction of hominin diets [27][28][29][30]. Stereomicroscopic dental microwear has also been applied to dinosaur species, mainly sauropods, hadrosaurs and ceratopsians [31][32][33][34][35][36][37][38]. Further work focused on different Triassic amniotes [39] or extinct heterodont crocodiles [40,41].…”