Laosaurus

stone lizard

• laas / laos · Greek · stone
• sauros · Greek · lizard

The name Laosaurus comes from the Greek words 'laas' (also spelled 'laos'), meaning 'stone', and 'sauros', meaning 'lizard' — so it literally means 'stone lizard'. It was named by the famous American paleontologist Othniel Charles Marsh in 1878. The name is thought to refer to the stony or petrified nature of the fossil material, a naming convention common in 19th-century paleontology. The genus was based on fragmentary vertebrae and other remains from the Morrison Formation of Wyoming.

Named by

Marsh

Year named

1878

Period

Late Jurassic

Stages

Kimmeridgian – Tithonian

Found in

Morrison Formation, Wyoming, USA

Laosaurus is generally considered a nomen dubium, as it is based on very fragmentary and non-diagnostic material (isolated vertebrae and teeth). Several species were originally assigned to it (e.g. L. celer, L. gracilis, L. consors), but most have since been reassigned to other genera or abandoned. It was a small ornithopod dinosaur. The fragmentary nature of the type material makes it impossible to reliably diagnose the genus or confidently refer other specimens to it.