Diplodocid

Diplodocids, or members of the family Diplodocidae ("double beams"), are a group of sauropod dinosaurs.Holtz, Thomas R. Jr. 2012. Dinosaurs: the most complete, up-to-date encyclopedia for dinosaur lovers of all ages. Winter 2011 AppendixGillette D.D. 1996, Stratigraphic position of the sauropod Dystrophaeus viaemalae Cope and its evolutionary implications. In: Morales, Michael (ed) The continental Jurassic. Museum of Northern Arizona Bulletin 60: 59-68. The family includes some of the longest creatures ever to walk the earth, including Diplodocus and Supersaurus, which may have reached lengths of up to .

With their peg-like teeth they could strip leaves from branches, and leave the grinding to gastroliths. They bacteria in their vast stomachs would break down the cellulose in the leaves, and the product would be absorbed further on in the alimentary canal.

The diplodocids have two sub-families:
Diplodocinae: Diplodocus and other long, slender forms.
Apatosaurinae: Apatosaurus and other stockier types.

Their cousins the brachiosaurs are put into a sister family. The much later titanosaurs were the last group of sauropods on Earth.

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