Diplodocus

double beam

• diplos · Greek · double
• dokos · Greek · beam

The name means "double beam" and refers to the paired, beam-like projections on the underside of the tail vertebrae (chevron bones). Marsh chose it because the chevrons had two projecting points, one forward and one backward, a feature he thought was unusual. Similar chevrons were later found in other sauropods.

Named by

Marsh

Year named

1878

Period

Late Jurassic

Stages

Kimmeridgian – Tithonian

Found in

Morrison Formation, western USA (Colorado, Utah, Wyoming, Montana)

A well-known diplodocid sauropod. The type species is Diplodocus longus.