Like other ichthyosaurs,
Eurhinosaurus was a high-speed swimmer, using the lateral oscillations of their caudal fluke on a flexible tail stock for swimming. The
postcranial morphology of
Eurhinosaurus was intermediate between those of very fast-swimmers and slower, more flexible predators.
Eurhinosaurus had a slender fusiform body with long limbs and fluke. Neural spines of fluke vertebrae were very short and almost erect. The relatively large hind limbs of
Eurhinosaurus suggested their use in steering and probably propulsion at a very low speed. The swimming style of
Eurhinosaurus was
thunniform. Their hypocercal caudal fin, which was mounted on the narrow
peduncle, moved through the water in a sinuous curve by the powerful muscles of the posterior trunk and the anterior tail region. From this motion, a strong force would be generated to push
Eurhinosaurus forward. Like other ichthyosaurs,
Eurhinosaurus probably was a deep diver.
Eurhinosaurus has a very large orbit with
scleral ring, a circular shaped bone that was embedded in their eye. The scleral ring was probably used to maintain the shape of their eyes against the high
pressure in the deep sea while they were diving. The big eye of
Eurhinosaurus suggested that they had very good visual capacity, which helped them see clearly in the dark environment of the deep sea.
Feeding mechanisms and diet Inferred from their extreme overbite, the genus probably used a predatory strategy close to
Xiphias, or the swordfish of today. The elongated, densely toothed upper jaw was used as weapon to penetrate or injure small soft prey items.
Eurhinosaurus belongs to the "Pierce I" predatory guild, so its dietary habits were consisted of small and soft, very delicate prey, such as small fishes, oysters, and
squid-like cephalopods. == Palaeoenvironment ==