Ichthyovenator: Early Cretaceous Asian spinosaurid with a split dorsal sail

Discovery and naming

Partial skeletal material attributed to Ichthyovenator was uncovered in Laos; the finds included vertebrae and pelvic elements among other bones. These fossils provided enough distinctive information for researchers to recognize it as a new taxon and to describe its anatomy in a formal publication.

Appearance and notable features

Ichthyovenator is considered a medium-sized member of its family. It is especially notable for an unusual dorsal profile formed by elongated neural spines along the vertebrae, producing a split or sinuous sail over the hip region. Like other spinosaurids, it had skull and tooth adaptations that resemble those of modern crocodiles, adaptations that are commonly interpreted as useful for catching aquatic prey.

Classification and geographic context

As a spinosaurid, Ichthyovenator adds to a small but growing record of this clade in Asia. In addition to Ichthyovenator, other spinosaurid occurrences on the continent include Siamosaurus and the taxon referred to as "Sinopliosaurus" fusuiensis. These discoveries indicate that spinosaurids were more widely distributed during the Early Cretaceous than once thought.

Paleobiology

Multiple lines of evidence suggest that many spinosaurids spent significant time near water and consumed aquatic prey. The jaw shape and tooth morphology seen in Ichthyovenator and its relatives are consistent with piscivory, although they may also have taken other kinds of food. Interpretations of their behaviour emphasize a semi-aquatic lifestyle rather than a purely terrestrial one.

• Temporal range: Early Cretaceous (about 125–113 Ma)
• Known from: fossil material recovered in Laos
• Group: Spinosauridae (fish-eating, crocodile-like theropods)