This positive/negative of a hatchling Keichousaurus (Pachypleuroceras) is the smallest specimen that we have ever seen. The bone detail is fantastic, particularly on the skull. From an old British collection, acquired before the 1980's.
Location: Guizhou Province, China
Age: Early Triassic - 240 million years old
Measurements: 3cm (length) x 2.5cm (width)
