A new genus and species of extinct ground shark, †Diprosopovenator hilperti, gen. et sp. nov. (Carcharhiniformes, †Pseudoscyliorhinidae, fam. nov.), from the Upper Cretaceous of Germany

Abstract

We describe a new genus and species of extinct ground shark, †Diprosopovenator hilperti, gen. et sp. nov. (Elasmobranchii, Carcharhiniformes), based on a single incomplete skeleton with dentition recovered from basinal marine late Cenomanian (Metoicoceras geslinianum ammonite zone) organic-rich deposits of northern Germany. The new carcharhiniform is characterized by a unique combination of dental morphologies, indicating close architectural resemblance to the family Scyliorhinidae (catsharks). However, the very distinct tooth root morphology readily separates the new taxon from all other scyliorhinids. The extinct Cretaceous carcharhiniform †Pseudoscyliorhinus (represented by †Ps. schwarzhansi and †Ps. reussi) shares tooth root morphologies and vascularization patterns with †Diprosopovenator, gen. nov. We hypothesize that these two sharks form part of an extinct group of carcharhiniforms characterized by a distinct root morphology (viz., low hemiaulacorhize roots with very flat and strongly flared basal faces protruding below the crown labially and mesiodistally and with a well-developed central labiobasal notch). Consequently, we propose a new family of Late Cretaceous carcharhiniforms, †Pseudoscyliorhinidae, fam. nov., to include the new taxon, as well as †Pseudoscyliorhinus. †Pseudoscyliorhinidae, fam. nov., shows a wide European distribution during the Late Cretaceous, ranging from the early Cenomanian to the late Campanian. The longevity of Scyliorhinidae, with a fossil record extending back into the Middle Jurassic, however, remains ambiguous and unresolved; therefore, it may be best to regard the assignment of fossil taxa to Scyliorhinidae as currently uncertain pending further taxonomic work.

Comment on the letter of the Society of Vertebrate Paleontology (SVP) dated April 21, 2020 regarding “Fossils from conflict zones and reproducibility of fossil-based scientific data”: the importance of private collections

“…-Sharks: René Kindlimann, in Klug and Bolliger 2012;Mollen et al 2012;Kriwet et al 2015;Pollerspöck et al 2018;Jambura et al 2018Jambura et al , 2019Bracher et al 2019;Stumpf et al 2019;Slater et al 2020;…”

Njoerdichthys dyckerhoffi gen. et sp. nov. (Pycnodontiformes, lower Turonian) northward migration caused by the Cretaceous Thermal Maximum

“…This succession of basinal, blackish laminated marlstones (“black shales”) belongs to the Hesseltal Formation ( Hiss et al, 2007a , 2007b ), which occurs in Westphalia and Lower Saxony (northern Germany). Although its academic exploitation did start only a couple of decades ago, it produced a large number of new insights into the occurrence and taxonomy of Cretaceous aquatic vertebrates ( Kriwet and Gloy, 1995 ; Maisch and Lehmann, 2000 ; Diedrich, 2001 , 2012 , 2014 ; Müller, 2008 ; Stumpf et al, 2019 ). Apart from these extraordinary Fossil Lagerstätten, significant fish finds in the basinal facies of the Late Cretaceous are rare (e.g.…”

“…Lithologically a bit incorrect, these laminated marls are referred to as “black shales”, which are famous for its well-preserved invertebrates (inoceramids: Hilbrecht and Dahmer, 1991 ; ammonites: Wippich, 2005 ; Hauschke et al, 2011 ; Klug et al, 2012 ; Kennedy and Kaplan, 2019 ; crustaceans: Neumann and Jagt, 2003 ; Hauschke et al, 2011 ; Schöllmann and Hauschke, 2012 ). Even more fascinating is the rich vertebrate assemblage ( Zawischa, 1982 ; Kriwet and Gloy, 1995 ; Maisch and Lehmann, 2000 ; Müller, 2008 ; Diedrich, 2012 , 2013 , 2014 ; Smith et al, 2019 ; Stumpf et al, 2019 ).…”