Diplodocus now common scientific opinion that "Seismosaurus hallorum" is a species of "Diplodocus". This genus of dinosaurs lived in what is now mid-western North America at the end of the Jurassic period. "Diplodocus" is one of the more common dinosaur fossils found in the middle to upper Morrison Formation, between about 154 and 152 million years ago, during the late Kimmeridgian age. The Morrison Formation records an environment and time dominated by gigantic sauropod dinosaurs, such as "Apatosaurus", "Barosaurus", "Brachiosaurus", "Brontosaurus", and "Camarasaurus". "Diplodocus" is among the most easily identifiable dinosaurs, with its typical sauropod shape, long neck and tail, and
Alan the Dinosaur Alan the Dinosaur Alan the Dinosaur is the name given to an unidentified Sauropodomoph fossil, found in Whitby in 1995, regarded as the oldest sauropod dinosaur found in the United Kingdom. It is now in the Yorkshire Museum. The fossil was discovered in Whitby in 1995 by Alan Gurr whilst on a field trip to the site led by geologist Phil Manning. A chunk of sandstone fell from cliff face and was inspected by the finder, who spotted the fragment of vertebra. As it is not identifiable to species level, it gained the nickname 'Alan' in commemoration of its finder.