Finally, we might have an answer for that long-standing palaeontological enigma!
Fischer V, Bardet N, Benson RBJ, Arkhangelsky M & Friedman M. 2016. Extinction of fish-shaped marine reptiles associated with reduced evolutionary rates and global environmental volatility. Nature Communications 7:10825. Freely available here and here (combined article + Supp Info) Covered in the several news, including Science, BBC, The European Commission, etc. See also ULg's Reflexion article here.
The last ichthyosaurs. Two ichthyosaurs (Pervushovisaurus bannovkensis) wander through a middle Cenomanian low latitude ecosystem that will prevail for most of the Late Cretaceous: high sea level and sea temperatures, rudist reefs (Ichthyosarcolites, Hippurites), newly radiating neoselacian sharks and acanthomorph fishes (Aipichthyoides). Artwork by © Andrey Atuchin 2016, based on Fischer & al 2016.
Fischer, Arkhangelsky, Stenshin, Uspensky, Zverkov & Benson 2015. Peculiar macrophagous adaptations in a new Cretaceous pliosaurid. Royal Society Open Science.
Open access, downloadable here!
During the Middle and Late Jurassic, pliosaurid plesiosaurs evolved gigantic body size and a series of craniodental adaptations that have been linked to the occupation of an apex predator niche. Cretaceous pliosaurids (i.e. Brachaucheninae) depart from this morphology, being slightly smaller and lacking the macrophagous adaptations seen in earlier forms. However, the fossil record of Early Cretaceous pliosaurids is poor, concealing the evolution and ecological diversity of the group. Here, we report a new pliosaurid from the Late Hauterivian (Early Cretaceous) of Russia. Phylogenetic analyses using reduced consensus methods recover it as the basalmost brachauchenine. This pliosaurid is smaller than other derived pliosaurids, has tooth alveoli clustered in pairs and possesses trihedral teeth with complex serrated carinae. Maximum-likelihood ancestral state reconstruction suggests early brachauchenines retained trihedral teeth from their ancestors, butmodified this feature in a uniqueway, convergent with macrophagous archosaurs or sphenacodontoids. Our findings indicate that Early Cretaceous marine reptile teeth with serrated carinae cannot be unequivocally assigned to metriorhynchoid crocodylomorphs. Furthermore, they extend the known diversity of dental adaptations seen in Sauropterygia, the longest lived clade of marine tetrapods.
We are delighted to announce that EDDyLab secured a significant grant from the FNRS to organise the upcoming ICGP596 meeting in Brussels. Link to dedicated website here.
Denayer J, Prestianni C, Gueriau P, Olive S & Clément G. 2015. Stratigraphy and depositional environments of the Late Famennian (Late Devonian) of Southern Belgium and characterization of the Strud locality. Geological Magazine.
Open access version (soon!)
Olive S, Clément G, Denayer J, Derycke C, Dupret V, Gerrienne P, Gueriau P, Marion Jean-marc, Mottequin B & Prestianni C. 2015. Flora and fauna from a new Famennian (Upper Devonian) locality at Becco, eastern Belgium. Geologica Belgica 18. 92–101.
Free publisher version
Olive S, Clément G, Daeschler E.B. & Dupret V. In Press. Characterization of the placoderm (Gnathostomata) assemblage from the tetrapod-bearing locality Of Strud (Belgium, Upper Famennian). Palaeontology, first view.
Bardet N, Fischer V, Machalski M. 2015. Large predatory marine reptiles from the Albian–Cenomanian of Annopol, Poland. Geological Magazine, first view.
Open-access author post print
During the Early–Late Cretaceous transition, marine ecosystems in Eurasia hosted a diverse set of large predatory reptiles that occupied various niches. However, most of our current knowledge of these animals is restricted to a small number of bonebed-like deposits. Little is known of the geographical and temporal extent of such associations. The middle Albian – middle Cenomanian
phosphorite-bearing succession exposed at Annopol, Poland produces numerous ichthyosaurian and plesiosaurian fossils. These are mostly isolated skeletal elements (e.g. teeth, vertebrae), but disarticulated partial skeletons and an articulated, sub vertically embedded ichthyosaur skull are also available. The following taxa are identified: ‘Platypterygius’ sp., cf. Ophthalmosaurinae, Ichthyosauria indet., Polyptychodon interruptus, Pliosauridae indet., Elasmosauridae indet. and Plesiosauria indet. The large-sized ichthyosaur ‘Platypterygius’ and the pliosaurid Polyptychodon interruptus predominate within the upper Albian – middle Cenomanian deposits. The Annopol record, combined with data from England, France and western Russia, suggests that ‘Platypterygius’ and Polyptychodon interruptus formed a long-term, stable ecological sympatry in marine ecosystems of the European archipelago, at least during the Albian – middle Cenomanian. In addition, the marine reptile assemblage from Annopol is distinct from other Eurasian ecosystems in containing also elasmosaurids in its Albian portion.
We are delighted to announce that EDDy Lab teams with RBINS and MNHN Paris to organize a session at the Geologica Belgica Meeting 2016 (Mons, Belgium, January 26-29, 2016):
Terrestrialization and the return to the sea: paleoecological and adaptative perspectives for major shifts of the history of life
You will be able to register and submit abstracts for the session via the website of the conference (deadline for abstract is Sept. 25 2015) https://sites.google.com/site/5thgbmeeting/home
When doing so, please do not forget to mention the name of the session where required.
Feel free to forward this message to any of your colleagues and students who might be interested.
We hope to see you in Mons for constructive exchanges of view, possibly around a few beers!
O. Lambert RBINS, Brussels, BE – A. Houssaye MNHN Paris, FR – V. Fischer University of Oxford, UK and ULg, BE
The EDDy Lab teams with RBINS to organize the IGCP596 meeting in Brussels, 20-22 September 2015! Check the dedicated website here.