Atopodentatus is an extinct genus of marine reptile, possibly basal sauropterygian, known from the early Middle Triassic (Pelsonian substage, Anisian stage) of Luoping County, Yunnan Province, southwestern China. It contains a single species, Atopodentatus unicus. It is thought to have lived between 247 and 242 million years ago. A near complete skeleton along with a left lateral fossil of the skull were discovered near Daaozi village, Yunnan, China. The scientific name derives from the peculiar zipper-shaped morphology of its jaws and unique dentition. The genus has been named Atopodentatus from Ancient Greek atopos (άτοπος), signifying "unplaceable, strange, extravagant, absurd, eccentric, disturbing", combined with Latin dentatus, "toothed", referring to the unusual form of arrangement and shape of the teeth. The specific name "unicus" reinforces the uniqueness of the reptile's morphology. Atopodentatus is 3 metres (9.8 ft) long. The geological strata in which the fossil was ...