Isolated pliosaurid teeth from the Albian–Cenomanian (Cretaceous) of Annopol, Poland

Abstract

ABSTRACT:Madzia, D. and Machalski, M. 2017. Isolated pliosaurid teeth from the Albian-Cenomanian (Cretaceous) of Annopol, Poland. Acta Geologica Polonica, 67 (3), 393-403. Warszawa.Brachauchenine pliosaurids were a cosmopolitan clade of macropredatory plesiosaurs that are considered to represent the only pliosaurid lineage that survived the faunal turnover of marine amniotes during the JurassicCretaceous transition. However, the European record of the Early to early Late Cretaceous brachauchenines is largely limited to isolated tooth crowns, most of which have been attributed to the classic Cretaceous taxon Polyptychodon. Nevertheless, the original material of P. interruptus, the type species of Polyptychodon, was recently reappraised and found undiagnostic. Here, we describe a collection of twelve pliosaurid teeth from the upper Albian-middle Cenomanian interval of the condensed, phosphorite-bearing Cretaceous succession at Annopol, Poland. Eleven of the studied tooth crowns, from the Albian and Cenomanian strata, fall within the range of the morphological variability observed in the original material of P. interruptus from the Cretaceous of England. One tooth crown from the middle Cenomanian is characterized by a gently subtrihedral cross-section. Similar morphology has so far been described only for pliosaurid teeth from the Late Jurassic and Early Cretaceous. Even though it remains impossible to precisely settle the taxonomic distinctions, the studied material is considered to be taxonomically heterogeneous.

Morphological and phylogenetic aspects of the dentition of Megacephalosaurus eulerti, a pliosaurid from the Turonian of Kansas, USA, with remarks on the cranial anatomy of the taxon

“…obs. ), and the assemblage of isolated tooth crowns once attributed to 'Polyptychodon' (Madzia, 2016;Madzia & Machalski, 2017), but differ from the teeth of Gallardosaurus iturraldei (Gasparini, 2009), Pliosaurus spp. (Knutsen, 2012;Benson et al 2013;Gasparini & O'Gorman, 2014;O'Gorman, Gasparini & Spolletti, 2018), Makhaira rossica (Fischer et al 2015), Stenorhynchosaurus munozi (Páramo-Fonseca et al 2016) and Luskhan itilensis (Fischer et al 2017), which are carinated and subtrihedral to trihedral, and the tooth crown of the Crimean pliosaurid (Zverkov, 2015), which is carinated and trihedral-to-'trapezoid' in its cross-sectional shape.…”

“…However, Madzia (2016) recently concluded that the dental material ascribed to P. interruptus does not show any autapomorphies and hypothesized that it is most likely too variable to represent a single species, prompting a revision of all other specimens attributed to this historical taxon (such studies are currently being undertaken; e.g. Sachs et al 2016b,c;Madzia & Machalski, 2017;Sachs et al 2018), rendering the taxon itself a nomen dubium. Indeed, detailed assessments of the dental morphology of pliosaurids with well-preserved dentitions might be crucial for these studies.…”

Increased pliosaurid dental disparity across the Jurassic–Cretaceous transition

“…, ; Zverkov ; Madzia ; Páramo‐Fonseca et al . ; Madzia & Machalski ; Gómez‐Pérez & Noè (see Zverkov et al . , documents for detailed account of each taxon included).…”

Estimating the evolutionary rates in mosasauroids and plesiosaurs: discussion of niche occupation in Late Cretaceous seas

“…Instead, if really belonging to a brachauchenine (and not a robust-toothed polycotylid), it seems to merely represent a relict of the once widespread pliosaurids. In turn, other isolated elements belonging to pliosaurids and polycotylids, such as those studied by Kear et al (2014), Madzia & Machalski (2017), , , Sachs et al (2020), and Zverkov & Pervushov (2020) might suggest a higher taxic diversity and a wider geographic distribution of the clades during the Albian-Turonian ('middle' Cretaceous).…”