SauropodomorphaDiplodocinaeNMMNH 3690

Diplodocus hallorum

NMMNH 3690

Known skeletal material of Diplodocus hallorum NMMNH 3690 — elements preserved drawn in white against a black body silhouette, estimated length ~30 m
Known material · Scale bar = 1 meter
Taxon
Diplodocus hallorum (Gillette, 1991)
Specimen
NMMNH 3690
Repository
New Mexico Museum of Natural History & Science
Formation
Morrison Formation
Locality
New Mexico, USA
Estimated length
~30 m (98 feet)
View
Left lateral
Basis
Known material only — holotype, too incompletely preserved to restore
Drawing
© Scott Hartman
Drawn
2006, revised 2026

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The holotype of Diplodocus hallorum, collected from the Morrison Formation of New Mexico and originally described in 1991 as a new genus, Seismosaurus. Only part of the skeleton was ever recovered, but it is enough to place this among the longest specimens of Diplodocus ever found…though at around 30 meters in length, it was far smaller than estimates published during its excavation and prep.

Because so much is missing, the page shows the known material on its own rather than a full reconstruction.

Other Diplodocus hallorum specimens

Known skeletal material of Diplodocus hallorum AMNH 223 — elements preserved drawn in white against a black body silhouette, estimated length ~28 m
AMNH 223

← all Diplodocus hallorum specimens