A partial skeleton of a Pliocene balaenid whale (Mammalia, Cetacea, Mysticeti) is described and compared to a large set of extant and fossil Balaenidae. The specimen (MCRE 232834) includes a jugal, both mandibular rami and part of the postcranial skeleton including several vertebrae, complete ribs, hyoid, pelvis, a single scapula and a single partial forelimb. The specimen was found at a site in the vicinity of the San Valentino Castle, about 16 km S from Reggio Emilia, close to the town of Castellarano, Emilia Romagna (northern Italy). Molluscs and foraminifers indicate a late Zanclean age for MCRE 232834, constrained between 3.8 and 3.6 Ma. A taphonomic analysis revealed that after death the individual sunk on the sea floor upside down and underwent a series of biostratinomic processes eventually leading to the collapse of the ribcage and to the disarticulation of the posterior thoracic, lumbar and caudal vertebrae, together with the loss of several skeletal elements including the skull. Shark teeth and encrusting molluscs demonstrate that the specimen was exploited by different organisms during its decay. The study of the skeleton revealed that MCRE 232834 shows an abruptly converging anterior ends of the mandibular rami, well-developed olecranon process in the ulna, peculiar morphology of the cervical vertebrae and enlarged attachment sites for axial muscles in the ribs. Based on the morphology of the cervical vertebrae, mandible and scapula, MCRE 232834 can be assigned to a new genus and species of the family Balaenidae, i.e., Charadrobalaena valentinae n. gen., n. sp., which is part of a primitive clade of balaenids that is the sister group of the crown balaenid whales. A functional analysis of the vertebral column revealed that it was able of comparatively faster and more agile swimming with respect to the extant balaenid species.The conodont study focused on biodiversity variation during the late Frasnian biologic crisis and across the Fr-Fm transition up to the end of recovery in the Palmatolepis minuta minuta Zone. Polygnathids dominate until the upper part of Zone 13b when palmatolepids become prevalent. In Zone 13c, their dominance continued into the lower Famennian. Increase of icriodids was paralleled by the onset of palmatolepid dominance. The end-Frasnian biological crisis impacted heavily on conodonts, extinguishing the ancyrodellids and wiping out all palmatolepids except for a single species, Palmatolepis ultima. The scenario cannot be attributed to anoxia because the seawaters were well oxygenated. The Lower and Upper Kellwasser extinction events (LKWE and UKWE), connected with the end-Frasnian biologic crisis were identifiable by conodonts even in the absence of sedimentary signatures of anoxic facies. The Lower Kellwasser Event is associated with a decreasing-temperature trend. Two phases of the Upper Kellwasser Event have been discriminated. Both are connected with decreasing temperature based on conodont apatite δ¹⁸O. Enhanced burial of organic matter is indicated by increase in δ¹³C measured on whole-rock carbonate in the Pramosio A section from the uppermost Zone 13b to the base of the Famennian. This positive shift in δ¹³Ccarb pre-dates the shift in δ¹⁸O. Conodont abundances are higher in Pramosio A than in Freikofel T. Exceptional abundances occur in Zone 13b in PRA section, peaking in pelagic environments with palmatolepid conodonts concurrent with increase of other pelagic biota, especially ammonoids and radiolarians. This is consistent with transgressive phases. Low abundances often coincide with rudstone levels equating with low-stand phases. Those in the early Famennian are inferred to reflect events during the worldwide biological crisis. Three transgressive-regressive cycles have been identified during Zone 13b in the Carnic Alps; the regressive trend of the last cycle persisted throughout Zone 13c when the basin reached low-stand conditions followed by a transgressive phase immediately above the Fr-Fm boundary. The transgressive-regressive cycles were of high frequency and possibly of fourth order because the time interval between the lower and upper Kellwasser positive δ¹³C excursions, equivalent to the interval uppermost Zone 12 to uppermost Zone 13c, has been estimated at about 600 kyr.

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