Diplodocus sp. (juvenile)

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Time: Late Jurassic (~150–145 million years ago)

Region: Montana, USA

Formation: Morrison Formation, Mother's Day Quarry

Coloration Data

In Gallagher et al. (2025), several skin specimens (CMC VP 20857, CMC VP 20858, CMC VP 15915, CMC VP 10660, VP 10662, and VP 10659) belonging to a juvenile Diplodocus were examined. The precise anatomical placement of these epidermal fragments on the body has not been determined. Elongated microbodies interpreted as fossilized melanosomes were discovered within the scales. Their dimensions fall within the size range of pheomelanosomes (brown/reddish pigments) of extant birds, as well as the melanosomes of the black caiman. The diversity of these structures suggests that the dinosaur's skin possessed an intricate color pattern, indicating that juvenile diplodocids were likely spotted or mottled. However, because fossil melanosomes can undergo diagenetic alterations in shape over geological time, the exact hues of this patterning remain unresolved.

Method: Scanning electron microscopy (SEM).

Publications

• Tess Gallagher, Dan Folkes, Michael Pittman, Tom G. Kaye, Glenn W. Storrs, Jason Schein (2025)
  A study of the coloration of a juvenile Diplodocus.

Documents and files

• Gallagher_et_al_2025.pdf (PDF)
  Article from Royal Society Open Science on the coloration of Diplodocus sp.

Reconstructions

Fossils

Size comparison