A new neoselachian shark from the Upper Triassic of Grozon (Jura, France)

Abstract

Two successive assemblages of vertebrate microremains have been found at Grozon (Jura, northeastern France). Palynological analysis confirms a Norian age for the first one and a Rhaetian age for the second. A new species of neoselachian shark, Grozonodon candaui , is erected from isolated teeth of Norian age, based on their enameloid ultrastructure. Distinctive parallel-fibred enameloid is recognized among teeth previously assigned to Hybodus minor , which therefore represents another early neoselachian shark. These structural characteristics confirm the close relationship of hybodont and neoselachian sharks.