Amphicoelias Fragillimus, potentially the largest dinosaur ever, is believed to have roamed the Late Jurassic period. Known primarily through fragmentary evidence, this sauropod may have reached lengths of up to 60 meters. Its immense size suggests it played a crucial role in its ecosystem, likely shaping vegetation patterns as a massive herbivore.

Amphicoelias fragillimus is a genus of sauropod dinosaur that lived during the Late Jurassic period, approximately 150 million years ago. Fossils attributed to this species have been found in what is now the Morrison Formation in the western United States, particularly in the state of Colorado.

During the Late Jurassic, the region that is now the Morrison Formation was characterized by a semi-arid climate with distinct wet and dry seasons. The environment consisted of floodplains with rivers and streams, as well as open woodlands and fern prairies.

Amphicoelias fragillimus, like other sauropods, was a herbivore that likely fed on a variety of vegetation, including conifers, ferns, and cycads. Its massive size suggests it played a significant role in the ecosystem by aiding in the spreading of plant seeds and creating pathways through dense vegetation.