Tanystropheus

Tanystropheus is an extinct genus of archosauromorph reptiles from the Middle Triassic of Europe. It is distinguished by an exceptionally long neck composed of many elongated cervical vertebrae, which was proportionally longer than its trunk. The skull is relatively small, and the teeth are sharp, indicating a carnivorous diet that likely targeted fish and other small aquatic prey. The overall body plan is compact, with limbs less elongated than the neck.

The ecology of Tanystropheus remains debated. Some reconstructions interpret the animal as aquatic or semi-aquatic, using the long neck to seize prey in shallow water while the body remained submerged or resting on the shore. Others suggest a more terrestrial habit or wading lifestyle. The neck’s biomechanics and wear patterns on the vertebrae continue to be analyzed to resolve these questions.

Fossils have been found mainly in the Besano Formation and at Monte San Giorgio, in what is now northern Italy and southern Switzerland. The rocks date to the Middle Triassic, roughly around the time of significant diversification of early archosauromorphs following the Permian-Triassic boundary.

Tanystropheus belongs to the family Tanystropheidae within Archosauromorpha. The most well-known species are Tanystropheus hydroides and Tanystropheus longobardicus, with several other named forms proposed over the years, though not all are universally accepted. Ongoing phylogenetic work continues to clarify its relationships with related long-necked reptiles.