Diplodocid

Skeletal reconstruction of Diplodocus in the Natural History Museum

• North America
• Asia
• Europe
• Africa

The Diplodocidae are a taxon of sauropod dinosaurs, which are detectable in the Upper Jurassic fossil. They include, inter alia Supersaurus and Seismosaurus, the largest known animals that ever inhabited the mainland. Better known representatives are Apatosaurus and Diplodocus. Sereno (1998) defined the Diplodocidae as originating line based taxon ( stem- based definition), which includes all taxa with Diplodocus as are more closely related with Dicraeosaurus. Some skin imprints of some diplodocids were first found by Stephen Czerkas in 1992 and were probably imprints of a tail.

Features

The representatives of the diplodocids were built relatively easily due to their bone anatomy. Neck and tail were significantly extended. Another feature is the long, low, sloping skull with pin-like teeth. The forelimbs were substantially shorter than the rear legs.

System

Outer systematics

The Diplodocidae is usually considered to be the sister taxon of Dicraeosauridae. Both groups are often, as summarized for example by Harisson and colleagues ( 2004), as Fragellicaudata and, together with the species and basal Rebbachisauridae group Diplodocoidea.

Cladogram to Harrison et al. (2004):

Diplodocidae

Dicraeosauridae

Rebbachisauridae

Upchurch et al. (2004 ), however, holds the Fragellicaudata invalid and provides all three families dar. as Schwesteraxa

Inside systematics

Lovelace and colleagues (2008 ) divide the Diplodocidae in the Apatosaurinae and in the Diplodocinae. While the Apatosaurinae includes, among others, the genera Apatosaurus and Supersaurus that Diplodocinae includes the two genera Diplodocus and Barosaurus.

Whitlock (2011 ), however, keep the Apatosaurinae for paraphyletic. Apatosaurus and Supersaurus are regarded as basal ( original ) genera. The Diplodocisaurinae is also absent; Diplodocus and Barosaurus are derived diplodocids.

Cladogram simplified after Withlock (2011):

Apatosaurus

Supersaurus

Dinheirosaurus

Tornieria

Barosaurus

Diplodocus

Genera

• Amphicoelias
• Apatosaurus
• Atlantosaurus
• Barosaurus
• Dinheirosaurus
• Diplodocus
• Dyslocosaurus
• Dystrophaeus
• Eobrontosaurus
• Kaatedocus
• Seismosaurus
• Supersaurus

Age and Paläobiographie

All secure the Diplodocidae assignable fossils date from the Kimmeridgian and Tithonian ( Upper Jurassic ). Finds originate mainly from the North American Morrison Formation. From Europe only Dinheirosaurus is known. An African Diplodocide is Tornieria.