AI imageMatch with prompt
86% (6/7 items)
Where the image differs from the prompt
- Neck still slender, not thick like BrontosaurusShould be: Deep, heavy body and thick robust neck
See the checklist, prompt and sources
- ✓Very long neck held forward and roughly horizontal, not upright
- ✓Extremely long whip-like tail held off the ground
- ✓Pillar-like legs, front legs slightly shorter, a single front clawThumb claw not clearly visible
- ✕Deep, heavy body and thick robust neckNeck still slender, not thick like Brontosaurus
- ✓Whole animal visible in side view
- ✓Scene matches the period and the fossil site
- ✓No text, people or modern objects
Checked by Claude Opus 5.5 (checked item by item from the image) on Oct 28, 2026. The score is the share of checklist items the image gets right; it is not an expert scientific review.
Prompt used to create the image
Scientifically accurate paleoart of Brontosaurus, a herbivore Diplodocidae dinosaur from Kimmeridgian–Tithonian times (154.8–143.1 million years ago). A very long neck held roughly horizontal, extending forward rather than straight up. An extremely long, whip-like tail held off the ground. Reference: Brontosaurus is a genus of herbivorous sauropod dinosaur that lived in present-day United States during the Late Jurassic period. It was described by American paleontologist Othniel Charles Marsh in 1879, the type species being dubbed B. excelsus, based on a partial skeleton lacking a skull found in Como Bluff, Wyoming. In subsequent years, two more species of Brontosaurus were named: B. parvus in 1902 and B. yahnahpin in 1994. Brontosaurus lived about 156 to 146 million years ago (mya) during the Kimmeridgian and Tithonian ages in the Morrison Formation of what is now Utah and Wyoming. Anatomy: pillar-like legs with the front legs slightly shorter than the hind legs, front feet with a single thumb claw; a deep, heavily built body and a thick, robust neck. Full body in side view, whole animal visible, standing in a semi-arid Late Jurassic floodplain like the Morrison Formation of western North America, with conifers, cycads, ginkgoes, tree ferns and ferns along a river, no grass and no flowering plants. Natural history museum illustration style, realistic textures and natural daylight, muted natural colors. No text, no labels, no humans, no modern objects.
Facts in the prompt come from Wikipedia (en) and Paleobiology Database
Brontosaurus
Name meaning: From Greek, meaning "thunder lizard".
📏 About 22 m long, longer than two buses, and around 15 tonnes.
📐 Compare its size with other dinosaurs →Find it in a game
In Drifting Continents, guess where its fossils were found on the ancient Earth · opens the game at globe.dinocodex.com
Pin Brontosaurus on the globe
Brontosaurus was a long-necked sauropod from Late Jurassic North America, with a thick, strong neck, a huge body on four pillar-like legs and a long whip-like tail.
Fun facts
- For about a century scientists treated Brontosaurus as a duplicate name for Apatosaurus, until a 2015 study found enough differences to make it a genus of its own again.
- It stayed one of the most famous long-necked dinosaurs even while its name was out of use.
Who lived alongside it
Dinosaurs found in the same rock formation as Brontosaurus (Morrison), so they lived in the same region at roughly the same time.
Allosaurus
Camarasaurus
Stegosaurus
Apatosaurus
Diplodocus
Camptosaurus
Nanosaurus
Dryosaurus
Formation data from the Paleobiology Database, counting only each genus's main formations. One formation can span hundreds of thousands to millions of years, so this doesn't mean any two of them ever met.
Scientific details
- Classification
- Sauropodomorph (long-necked)
- Family
- Diplodocidae
- When it lived
- 143.1–154.8 million years ago
- Geologic stages
- Kimmeridgian – Tithonian
- Named by
- Marsh, 1879
- Fossil occurrences
- 23 sites
Countries with fossils
- United States
Data from Paleobiology Database and Wikidata