Elasmobranch (Chondrichthyes) assemblages from the Albian (Lower Cretaceous) of Ukraine

A new hybodontiform shark (StrophodusAgassiz 1838) from the Lower Cretaceous (Valanginian-Hauterivian) of Colombia

“…nov. Recently Sokolskyi & Guinot (2021) suggest a pending taxonomic status for Asteracanthus (= Sphaenonchus ) compressus Rogovich, 1860 , from Albian deposits of Ukrainian due to the disappearance of the holotype. The only existing evidence of A .…”

“…9–10), which shows what appear to be tooth fragments and the base of a cephalic spine. Sokolskyi & Guinot (2021) considered this species name as valid pending further sampling and/or information on the whereabouts of the missing specimen, which would be essential to clarify the taxonomy of this dubious species. Asteracanthus aegyptiacus Stromer, 1927 , from the Late Cretaceous of Africa, was described based on isolated dorsal and cephalic spines; but recently, Michaut (2017) , using a great number of isolated fin and cephalic spines and teeth from the Maastrichtian of Niger, attempted to reconstruct the dentition of this species.…”

First occurrence of pterosaurs in Ukraine from the Albian (Lower Cretaceous) Burim Formation, Kaniv Natural Reserve

“…Burim Formation deposits within the Kaniv Natural Reserve include five layers of quartz-glauconite sands containing vertebrate fossils, as previously described by Sokolskyi & Guinot (2021). Four of the layers (A, B, C, and D) are exposed at the study site, but no vertebrate fossils have been found in layer D (Fig.…”

“…1B). These strata were estimated to be Upper Albian based on elasmobranch dental remains and findings of Mortoniceras inflatum ammonites (Sokolskyi & Guinot, 2021) and were deposited in a warm epicontinental sea in the northern part of Tethys (Menasova & Tymchenko, 2018).…”

“…A diverse upper Albian vertebrate assemblage is present in the Burim Formation deposits of the Kaniv Natural Reserve in the Cherkassy region, Ukraine. Elasmobranch specimens were recently characterized from this area (Sokolskyi & Guinot, 2021) which, combined with additional undescribed cartilaginous fish, teleosts, ichthyosaurs, plesiosaurs, and testudines, suggests a primarily marine deposit. Nonetheless, as described here, the site also yielded several teeth belonging to pterosaurs, which represent the first known pterosaur material from Ukraine.…”