Dinosaurs That Start With O
Explore a complete list of over 30 dinosaurs that start with the letter O.
Each dinosaur listed has a dedicated page with information on classification, diet, size, fossil evidence, geographic distribution, and maps of known fossil locations, where available. Pages may also include size comparison charts, fossil representations, and in-depth descriptions based on current scientific research.
The amount of information varies by species, depending on the completeness of fossil discoveries.
Diet: Herbivore.Size: Total body size uncertain due to lack of
remains.Time Period: Kimmeridgian/Tithonian of the Jurassic.
Diet: Herbivore.Size: Tibia about 405 millimetres (0.45 meters)
long. Total body size unknown due to overall lack of fossil remains.Time Period: Toarcian of the Jurassic.
Diet: Herbivore.Size: Estimated†at up to 6†‬meters long.Time Period: Maastrichtian of the Cretaceous.
Diet: Uncertain.Size: Uncertain due to lack of remains, but possibly about 1.8 to 2.1 meters long..Time Period: Maastrichtian of the Cretaceous.
Diet: Uncertain.Size: Roughly estimated at about†‬1.2-1,2†‬meters
long.Time Period: Late Cretaceous.
Diet: Herbivore.Size: Up to†‬12†‬meters long.Time Period: Maastrichtian of the Cretaceous.
Diet: Herbivore.Size: Around†‬10†‬to just over†‬15†‬meters
long.†‬Full size depends upon the species.Time Period: Bathonian/Callovian of the Jurassic.
Diet: Insectivore�Size: Unavailable.Time Period: Campanian of the Cretaceous.
Diet: Herbivore.Size: Estimated up to†‬6†‬meters long.Time Period: Campanian of the Cretaceous.
Diet: Herbivore.Size: Estimated at†11 to 13†‬meters long.Time Period: Campanian to Maastrichtian of the
Cretaceous.
Diet: Carnivore.Size: Uncertain due to incomplete fossil material.Time Period: Maastrichtian of the Cretaceous.
Diet: Herbivore.Size: Unavailable.Time Period: Campanian of the Cretaceous.
Diet: Carnivore.Size: Uncertain due to lack of fossils,†‬but
comparison to related genera suggests that Ornithodesmus
grew to
roughly about†‬1.8†‬meters long.Time Period: Early Cretaceous.
Diet: Carnivore.Size: Estimated at†‬2†‬meters long,†‬possibly
slightly†‬larger.Time Period: Kimmeridgian of the Jurassic.
Diet: Possible omnivore.Size: Exact size depends upon the species in
question.†Larger individuals approximately 3.8 meters long.Time Period: Campanian to Maastrichtian of the
Cretaceous.
Diet: Herbivore.Size: Uncertain.Time Period: Barremian of the Cretaceous.
Diet: Herbivore.Size: Estimated about†‬2.5†‬meters long.Time Period: Campanian of the Cretaceous.
Diet: Carnivore.Size: Unknown due to lack of remains.†‬Holotype
tooth†‬is†‬27†‬millimetres long.Time Period: Maastrichtian of the Cretaceous.
Diet: Herbivore.Size: 2.1 meters long for adults.Time Period: Cenomanian of the Cretaceous.
Diet: Herbivore.Size: Precise size uncertain due to lack of
remains,†‬but estimated to be in the region of about†‬4-5†‬meters
long.Time Period: Late Barremian of the Cretaceous.
Diet: Carnivore/Piscivore.Size: Unknown due to lack of fossil remains.â€
‬Holotype tooth is†‬49†‬millimetres long.Time Period: Mid Tithonian of the Jurassic.
Diet: Carnivore/insectivore.Size: Uncertain due to lack of remains.Time Period: Late Jurassic.
Diet: Herbivore.Size: Uncertain but probably somewhere in the region
of†‬1.5†‬to†‬2†‬meters long.Time Period: Oxfordian/Tithonian of the Jurassic.
Diet: Herbivore.Size: About†‬2†‬meters long.Time Period: Late Jurassic.
Diet: Herbivore.Size: 7†‬to†‬8†‬meters long,†‬67†‬centimetre
skull.Time Period: Aptian to Cenomanian of the Cretaceous.
