Mosasauroid predation on an ammonite – Pseudaspidoceras – from the Early Turonian of south-eastern Morocco

Abstract

ABSTRACT:Gale, A.S., Kennedy, W.J. and Martill, D. 2017. Mosasauroid predation on an ammonite -Pseudaspidoceras -from the Early Turonian of south-eastern Morocco. Acta Geologica Polonica, 67 (1), 31-46. Warszawa.A juvenile specimen of the ammonite Pseudaspidoceras from the Early Turonian of the Goulmima area in the Province of Er-Rachida in south-eastern Morocco shows clear evidence of predation by a tooth-bearing vertebrate. Most of the body chamber is missing, as a result of post-burial compactional crushing. The adapertural part of the shell on the left flank of the surviving fragment of body chamber bears six circular punctuations; the right flank four. These are interpreted as the product of a single bite by a mosasauroid, probably a Tethysaurus.The taxonomy of the Goulmima Pseudaspidoceras is discuused in an appendix.

The old and the new plankton: ecological replacement of associations of mollusc plankton and giant filter feeders after the Cretaceous?

“…The extreme differences in size (up to three orders in magnitude) between adults and juveniles in large ammonites indicate that the range of potential predators changed significantly throughout the life history of these cephalopods. As hatchlings and small juvenile planktonic forms, moderate-sized to large suspension feeders and small predators likely used them as a food source but for adult puzosiids and other large ammonites, only large predators such as mosasaurs, pliosaurs and large fishes can be considered, although the seeming direct evidence for such a trophic relationship is still under debate ( Kauffman & Kesling, 1960 ; Tsujita & Westermann, 2001 ; Kauffman, 2004 ; Gale, Kennedy & Martill, 2017 ). Latest Cretaceous juvenile ammonites were possibly not the primary food source of ichthyosaurs since the latter became extinct already in the Cenomanian and are unknown from stomach contents to our knowledge.…”

A new cuspidate ptychodontid shark (Chondrichthyes; Elasmobranchii), from the Upper Cretaceous of Morocco with comments on tooth functionalities and replacement patterns

“…The probable ammonite hunters † Asflapristis and † Ptychotrygon (sclerorhynchid sawfishes) can be instead considered third-level predators. Generalist elasmobranchs (predators/scavengers), such as † Squalicorax , that were able to feed on an even larger prey (e.g., marine reptiles and other sharks) conversely occupied the top of the trophic hierarchies (‘apex predators’; see also Stewart, 1980 ; Schwimmer et al, 1997 ; Everhart and Caggiano, 2004 ; Gale et al, 2017 ; Ehret and Harrell, 2018 ; Amadori et al, 2020a ; Cooper and Martill, 2020 ). The early Turonian marine environment of the Goulmima/Asfla region ( Fig.…”

“…mosasauroids and plesiosaurs) and, more rarely, elasmobranchs (e.g. Bardet et al, 2003a , b ; Kennedy et al, 2008 ; Cavin et al, 2010 ; Claeson et al, 2013 ; Angst and Bardet, 2015 ; Gale et al, 2017 ; Meister et al, 2017 ; Allemand et al, 2018 ; Villalobos-Segura et al, 2019 , 2021 ; Cooper and Martill, 2020 ). Additionally, the limestones of the Akrabou Fm include shell beds, with a low-diversified bivalve assemblage, and stromatolites in various horizons ( Kennedy et al, 2008 ; Cooper and Martill, 2020 ).…”

Planktonic foraminifera document palaeoceanographic changes across the middle Cenomanian carbon-isotope excursion MCE 1: new evidence from the UK chalk

“…Paul et al 1994; Gale & Christensen, 1996; Wilmsen, 2003). Similarly, a southward incursion of boreal assemblages containing Praectinocamax plenus characterizes cooling episodes known as the Plenus Cold Event (PCE; Gale & Christensen, 1996; Jarvis et al 2011; Jenkyns et al 2017; Gale et al 2019a; O’Connor et al 2019) that interrupted the supergreenhouse conditions during part of the Cenomanian–Turonian positive δ 13 C excursion that identifies the OAE 2.…”