Placodonts ("Tablet teeth") were a group of marine reptiles that lived during the Triassic period, becoming extinct at the end of the period. It is believed that they were part of Sauropterygia, the group that includes plesiosaurs. Placodonts were generally between 1 to 2 metres (3 to 7 ft) in length, with some of the largest measuring 3 metres (10 ft) long.

The first specimen was discovered in 1830, and they have since been discovered throughout central Europe, North Africa, the Middle East and China.

Read more about PlacodontsPalaeobiology, Classification

Other articles related to "placodonts, placodont":

Placodonts - Classification
... was previously considered to be a basal superfamily of placodonts with the sole member Helveticosaurus ... However, it is now thought that Helveticosaurus was not a placodont but possibly an unusual member of the Archosauromorpha ...
... This aquatic animal was a nothosaur, an early relative of the plesiosaurs and placodonts ... Pachypleurosauria Nothosauria Pistosauroidea Plesiosauria Placodontia Basal placodonts Paraplacodus Pararcus Placodus Cyamodontoidea Macroplacus ...
Placodont - Palaeobiology
... But unlike the marine iguana, which feeds on algae, the placodonts ate molluscs and so their teeth were flat and tough to crush their shells ... as ichthyosaurs and nothosaurs, and later placodonts developed bony plates on their backs to protect their bodies while feeding ... By the Late Triassic, these plates had grown so much that placodonts of the time such as Henodus and Placochelys resembled the sea turtles of modern day ...