The Diet of Metriorhynchus (Thalattosuchia, Metriorhynchidae): Additional Discoveries and Paleoecological Implications

Abstract

A new metriorhynchid specimen with stomach contents is described here. Assigned to Metriorhynchus cf. superciliosus., this specimen has a clear longirostrine form as indicated by its gracile and elongated mandibular rami. This is the second example of gastric contents described for Metriorhynchidae. This specimen’s preservation allows the identification of the gill apparatus remains of Leedsichthys, the giant suspension-feeding osteichthyan from the Jurassic, including its gill rakers. The gastric contents also contain remains of invertebrates. This specimen indicates that Leedsichthys was not the direct prey of these crocodiles but more that its body was scavenged by them. Longirostrine metriorhynchids were piscivorous but also opportunistic and may have had more of a scavenging component in their lifestyle than previously understood, as all discovered fossils point in this direction.