Barosaurus (Barosaurus lentus Marsh, 1890) - Size, Diet & Jurassic Period Facts

Q: What makes Barosaurus scientifically significant?

Barosaurus provides critical insights into the evolutionary radiation of Sauropodomorpha. Holotypes and fossil evidence indicate: Iconic mounted skeleton rearing up on its hind legs at the American Museum of Natural History, NYC.

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Barosaurus (Barosaurus lentus Marsh, 1890) - Size, Diet & Jurassic Period Facts | DinoOrigin

Evolutionary Taxonomy & Cladistics

View Dinosaur Phylogeny

Phylogenetic classification of Barosaurus lentus Marsh, 1890 based on peer-reviewed cladistic analyses of diagnostic skeletal synapomorphies.

Taxonomic Rank	Taxon / Clade	Diagnostic Context
Kingdom	Animalia	Monophyletic prehistoric clade
Phylum	Chordata	Monophyletic prehistoric clade
Clade	Dinosauria	Monophyletic prehistoric clade
Order	Saurischia (Lizard-Hipped Dinosaurs)	Characterized ancestrally by a triradiate pelvis with an anteriorly pointing pubis.
Suborder	Sauropodomorpha	Herbivorous saurischians characterized by elongated necks, columnar limbs, and enormous body volumes.
Genus	Barosaurus	Monophyletic prehistoric clade
Species	Barosaurus lentus Marsh, 1890	Specific authority designation

Anatomy & Physical Characteristics

Barosaurus ('heavy lizard') was an imposing diplodocid sauropod from the Late Jurassic Morrison Formation. While closely related to Diplodocus, Barosaurus possessed a significantly longer neck consisting of 16 heavily elongated cervical vertebrae, balanced by a relatively shorter tail.

Its immense reach allowed it to browse upper forest canopies or sweep across broad expanses of riverine vegetation.

Diagnostic Morphological Traits

Graceful diplodocid silhouette with an extremely long neck, slender pencil-like teeth, and pillar-like limbs.

Comparative Scale & Biometrics

Anatomical dimensions relative to an average adult human (1.8 m / 6 ft tall)

Approx. 15.0× human length

Barosaurus (Length)24–27 m (78.7–88.6 ft)

Adult Human1.8 m (6.0 ft)

Length

24–27 m (78.7–88.6 ft)

Height

5–6.5 m (16.4–21.3 ft)

Estimated Mass

18.0–26.0 metric tons (39,683–57,320 lbs)

Diet & Feeding Ecology

All Herbivore Species

Trophic Guild: Herbivore

Herbivorous; stripped leaves from tall conifers, ginkgoes, and ferns.

Paleobiology & Behavior

Extremely long-necked sauropod utilizing its cervical column to reach high tree canopies without rearing. It shared the expansive Morrison river floodplains with allied diplodocids such as Diplodocus and lived alongside formidable apex carnivores like Allosaurus.

Habitat & Ecological Biome

Prehistoric Depositional Setting

Inland river systems and floodplain forests of the American West.

Fossil Evidence & Specimen Records

Preserved Skeletal Material & Bonebeds

Iconic mounted skeleton rearing up on its hind legs at the American Museum of Natural History, NYC.

Discovery & Taxonomic Naming History

Year of Discovery / Description1889

Type Specimen Locality & FormationMorrison Formation, South Dakota, United States

Found by Mrs. E. R. Ellerman; named by O.C. Marsh in 1890.

Geological Era & Chronostratigraphy

Explore All Jurassic Period Fauna

Jurassic Period PeriodTemporal Interval: 155–150 Ma (million years ago)

Marked by lush greenhouse climates, the breakup of Pangaea, and the evolutionary explosion of sauropods, plated stegosaurs, and apex megalosauroid and allosauroid theropods.

Where It Lived & Paleoenvironment

North America Dinosaurs

During the Mesozoic Era, continental drift progressively reconfigured land bridges, atmospheric currents, and regional precipitation regimes. Fossils of Barosaurus evidence its adaptation to the paleoenvironments of North America.

Paleogeographic RealmNorth America (North America)

Home to the fossil-rich Morrison Formation of the Late Jurassic and the Hell Creek and Dinosaur Park Formations of the Late Cretaceous.

Fossil Discovery Locality

Scientific Significance & Evolutionary Impact

The anatomical architecture of Barosaurus serves as a crucial benchmark in vertebrate paleontology, illustrating key adaptive radiations within Sauropodomorpha.

Phylogenetic Placement: Informs cladistic debates concerning the divergence, skull biomechanics, and skeletal evolution of Jurassic Period fauna.
Paleoecological Guild: Documents trophic specialization (Herbivore) and predator-prey dynamics across its regional ecosystem.
Taphonomic Record: Iconic mounted skeleton rearing up on its hind legs at the American Museum of Natural History, NYC.

Frequently Asked Questions About Barosaurus

Scientifically verified answers based on peer-reviewed paleontological evidence.

Q1.When did Barosaurus live?

Barosaurus lived during the Jurassic Period Period, approximately 155–150 Ma (million years ago). This places it within the Mesozoic Era.

Q2.How big was Barosaurus?

Paleontological estimates place Barosaurus at a length of 24–27 m (78.7–88.6 ft), a hip/standing height of 5–6.5 m (16.4–21.3 ft), and a body mass of 18.0–26.0 metric tons (39,683–57,320 lbs).

Q3.What was the diet of Barosaurus?

Classified as a herbivore, Barosaurus specialized in consuming Herbivorous; stripped leaves from tall conifers, ginkgoes, and ferns..

Q4.Where were Barosaurus fossils discovered?

Fossil specimens of Barosaurus have been recovered from Morrison Formation, South Dakota, United States, with notable historic specimens documented in 1889. Found by Mrs. E. R. Ellerman; named by O.C. Marsh in 1890.

What makes Barosaurus scientifically significant?

Academic Literature & Peer-Reviewed References

Authoritative citations establishing the factual taxonomy, biometrics, and anatomy of Barosaurus.

American Journal of ScienceView Publication
Marsh, O. C. (1890). Description of new dinosaurian reptiles. American Journal of Science, 39(229), 81-86. https://doi.org/10.2475/ajs.s3-39.229.81
Curated & Verified: 2026-09-24

Barosaurus

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