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Lower Jurassic (Pliensbachian-Toarcian) belemnites from Fresney-le-Puceux (Calvados, France): taxonomy, chronostratigraphy and diversity ABSTRACT The present paper deals with the systematic description of the belemnite assemblages from the Lower Jurassic, collected at the Roche Blain quarry, Fresney-le-Puceux. In spite of the reduced thickness of the succession at Fresney-le-Puceux, 13 successive ammonite chronozones could be documented in this rather unique outcrop situation in mainland Europe. Twelve genera and 26 species of belemnites belonging to the Passaloteuthididae, Hastitidae, Megateuthididae, Salpingoteuthididae, and family 88 GEODIVERSITAS • 2018 • 40 (4) Weis R. et al. MOTS CLÉSBélemnites, ammonites, céphalopodes, stratigraphie, Pliensbachien, Toarcien, carrière la Roche Blain, Normandie.incertae sedis are described and illustrated herein. The stratigraphical range of the belemnites is correlated with the standard ammonite zonation, using the chronozone concept: the described specimens range from the lower Pliensbachian (Davoei Chronozone) to the uppermost Toarcian (Aalensis Chronozone) while ammonites indicate the Aalenian (Murchisonae Chronozone) to be present too, but these beds delivered no identifiable belemnites so far. The belemnite diversity from Normandy is compared to data from coeval outcrops in Western and Central Europe. RÉSUMÉBélemnites du Jurassique inférieur (Pliensbachien-Toarcien) de Fresney-le-Puceux (Calvados, France) : taxonomie, chronostratigraphie et diversité. Cet article traite de la systématique des bélemnites du Jurassique inférieur récoltées dans la carrière de la Roche Blain à Fresney-le-Puceux. Malgré l'épaisseur réduite de la succession de Fresney-le-Puceux, 13 chronozones successives d'ammonites ont été documentées dans cet affleurement assez unique en Europe continentale. Douze genres et 26 espèces de bélemnites appartenant aux Passaloteuthididae, aux Hastitidae, aux Megateuthididae et aux Salpingoteuthididae, ainsi qu'à une famille incertae sedis, sont décrits et illustrés ici. L'extension stratigraphique des bélemnites est corrélée avec la zonation standard des ammonites en utilisant le concept de chronozone : les spécimens décrits s'étendent du Pliensbachien (Chronozone à Davoei) au Toarcien supérieur (Chronozone à Aalensis), tandis que les ammonites indiquent que l'Aalénien (Chronozone à Murchisonae) pourrait être présent, mais ces niveaux n'ont pas livré de bélemnites identifiables jusqu'ici. La diversité des bélemnites de Normandie est comparée à celle d'affleurements équivalents en Europe occidentale et centrale. Hastites subclavatus (Voltz, 1830)

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Here we report on four highly peculiar skate teeth from Arcille and Certaldo, two Pliocene localities of Tuscany (central Italy). While being attributable to Rajiformes and somewhat reminiscent of Dipturus and Rostroraja, these specimens display an unusual multicuspid tooth design that does not match any extinct or extant skate taxon known to date. The studied teeth are thus referred to a new genus and species of Rajiformes, Nebriimimus wardi gen. et sp. nov., which is here tentatively assigned to the family Rajidae. Based on pronounced morphological similarities between the rather large-sized teeth of the latter and those of extant nurse sharks, we hypothesise that N. wardi might have been capable of actively foraging upon relatively large food items compared to other rays. This extinct skate species was likely not a common component of the Pliocene Tuscan marine vertebrate assemblages. The palaeoenvironmental scenarios that N. wardi inhabited were marginal-marine and open shelf settings characterised by tropical climate conditions. As N. wardi is currently known only from lower to mid-Pliocene deposits of the Mediterranean Basin, it is tempting to speculate that its speciation dates back to an earliest Pliocene phase of diversification that also contributed to the emergence of the Mediterranean endemic stock of extant skate species.

Sharks assigned to the carcharhiniform family Scyliorhinidae account for about 160 extant species placed in 18 genera. Most living scyliorhinids are small- to medium- sized ground sharks provided with cat- like eyes and nasal barbels similar to whiskers; hence their vernacular name, "cat- sharks". Living catsharks mostly inhabit deep or rather deep waters of the warm and temperate seas worldwide, foraging on small fishes and inverterbates. In the present paper, we report on a lateral tooth of Scyliorhinidae collected from a clay pit at Certaldo (central Italy), where marine mudstones belonging to the famously fossiliferous Pliocene successions of Tuscany are exposed. This catshark specimen represents the second bona fide record of the extinct premontreine species Pachyscyllium distans in the Pliocene of the Mediterranean Sea, as well as the geologically youngest confirmed occurrence of this species worldwide. In the Mediterranean Pliocene, P. distans thus coexisted with the similar but distinct species Pachyscyllium dachiardii. After having been widespread in Northern Atlantic, Paratethyan, and Mediterranean waters in Miocene times, P. distans became confined to the Mediterranean Sea during the Pliocene. Therefore, similar to what has recently been suggested for P. dachiardii, we hypothesise that the range of P. distans contracted southward as colder conditions took hold in the Northern Hemisphere. The eventual extinction of P. distans might be related to the first cooling episode that significantly affected the Mediterranean biota around 3 Ma.