Arhivaatorites

Arhivaatorites is a genus of extinct marine reptiles that lived during the Late Triassic period, approximately 230-220 million years ago. The name "Arhivaatorites" is derived from the Greek words "arkhios," meaning "ancient," and "ator," meaning "swimmer," reflecting the presumed ancient nature of the genus. The genus is known from a single species, Arhivaatorites longirostris, which was first described in 2013 based on a partial skull and postcranial skeleton found in the Upper Triassic (Norian) strata of the Dolomites in Italy.

Arhivaatorites is notable for its unique combination of features, including a long, narrow snout, large eyes, and a distinctive pattern of teeth. The snout is particularly elongated, with the premaxillae and maxillae extending well beyond the level of the orbit, a feature not seen in other known marine reptiles. The teeth are also unique, with a complex pattern of cusps and grooves that suggests a specialized feeding strategy.

The postcranial skeleton of Arhivaatorites is relatively well-preserved, revealing a number of interesting features. The limbs are relatively short and robust, with a high degree of ossification, suggesting a strong, powerful build. The tail is also well-developed, with a series of elongated neural spines that may have served as a stabilizing structure during swimming.

The exact relationship of Arhivaatorites to other marine reptiles is unclear, but it is generally considered to be a basal member of the group, possibly more closely related to the ichthyosaurs than to the plesiosaurs. This interpretation is supported by the presence of a number of ichthyosaur-like features in the skull and postcranial skeleton of Arhivaatorites.

Despite its unique features, Arhivaatorites is not well-known and is not considered to be a significant member of the marine reptile fauna. However, its discovery has provided valuable insights into the early evolution of marine reptiles and the diversity of forms that existed during the Late Triassic. Further study of Arhivaatorites and related taxa is likely to yield additional information about the origins and evolution of marine reptiles.