New longirostrine crocodylomorph remains from the Blesa Formation, Barremian, in the Iberian Peninsula, Spain

Purpose Crocodylomorpha has been a highly morphologically and ecologically diverse clade over time. During the Mesozoic and Cenozoic, several crocodylomorph lineages colonized the marine environment; however, by the late Early Cretaceous the extinction of Thalattosuchia and the origination of new marine forms occur, and the “Middle” Cretaceous is a period of time where marine crocodylomorphs are poorly known. Here we describe two rostrum fragments (MPZ 2016/78 and MPZ 2016/79) collected in the upper part of the Blesa Formation (Barremian, Lower Cretaceous) in Teruel (Spain). The “Upper” Blesa Fm has been interpreted as a coastal–transitional depositional environment. Results The specimens correspond to long-snouted crocodylomorphs. MPZ 2016/78 is the left half of a fragmentary rostrum with heterodonty in dentition size, M4? and M5? being the largest alveoli. This suggests that it belongs to a crocodylomorph with a generalist diet. By contrast, MPZ 2016/79 is a fragmentary right half of a more gracile and slender long rostrum. It is homodont in size, with several small teeth, common in animals specialized for ichthyophagy. Conclusions MPZ 2016/78 and MPZ 2016/79 have been assigned to Crocodylomorpha indet. This new crocodylomorph material, together with the fossil remains of marine vertebrates previously found in the same region (plesiosaurs, chelonians, osteichthyans, chondrichthyans and a new crocodylomorph), suggests that the “Upper” Blesa Formation was a coastal zone with a great wealth of fauna, making it an interesting area for the study of Barremian marine vertebrates.