Natural History

Natural History

View full screen - View 1 of Lot 4. A Mounted Plesiosaur Skeleton.

A Mounted Plesiosaur Skeleton

Lower Jurassic (approx. 190 million years ago), Lower Lias, Blockley, Gloucestershire, England

Auction Closed

July 26, 08:15 PM GMT


600,000 - 800,000 USD

Lot Details


A Mounted Plesiosaur Skeleton

Plesiosaur cryptoclidus sp. (likely C. eurymerus)

Lower Jurassic, Lower Lias (approx. 190 million years ago)

Blockley Quarry, Blockley, Gloucestershire, England

132 inches (11 feet) in length; skull length approx. 10 ½ inches from base to tip. Roughly 130 fossil bones with additional cast elements.

Mounted on a custom armature in 8 sections that can be assembled and rigged in two places from the rib cage for hanging. Sections comprising the mounted skeleton are: Skull; Neck; Torso/ribcage (including breast plate and pelvis); Tail; and each of four flippers.

The skeleton has a complete thorax, as well as parts of its tail, neck, limbs and even parts of the fragile skull, with bones preserved intact without distortion, and densely mineralized.

Discovered in the Blockley quarry, Gloucestershire, England in the early 1990s;

Private German collection;

Sotheby's Paris, Natural History, 2010 (lot 51);

American collection, acquired in the above


Plesiosaurs represent a diverse family of aquatic reptiles that adapted to life in the open seas. The fossil record shows that plesiosaurs lived all over the world from the Triassic to the end of the Cretaceous Period, where they became extinct together with the dinosaurs 65 million years ago. They evolved a unique body design not seen in other marine creatures. Their relatively small heads had jaws packed with numerous menacing, long pointed teeth on a snake-like neck. Although the body was rigid, it could nonetheless swim rapidly using its large, powerful flippers. In contrast to the elongated neck, the tail was relatively short. Currently, the scientific knowledge that has been gathered indicates that plesiosaurs were extremely fast predatory reptiles. They may have hunted fish and squid, as well other small prey. One fossil specimen discovered in Late Cretaceous rocks in Kansas had fetal bones preserved in the body cavity, demonstrating that at least some plesiosaurs (Polycotylus species) gave birth to living young (viviparous) rather than laying eggs.

The prolific fossil hunter Mary Anning discovered the first skeleton of a Plesiosaur in 1823 on England’s famous “Jurassic Coast” in Lyme Regis. The discovery sparked much debate due to the reptile’s odd appearance, and even inspired geologist Thomas Hawkins’s “Book of the Great Sea Dragons,” published in 1840. The Natural History Museum in London showcases several of Anning’s finds, including her Plesiosaur. Mary Anning is one of the most influential women in the history of paleontology; her contributions to the science remain unequalled. 

The history of the Plesiosaur is intertwined with that of the elusive Loch Ness monster of Scottish folklore, as many have drawn morphological comparisons between the Plesiosaur and the infamous “Nessie,” whose sightings stretch back to the sixth century, but increased significantly following the discovery in the early 19th century. Although accounts of the monster differ, recorded sightings have described “Nessie” with a long neck, small head, and four flippers, making it extremely similar in appearance to Plesiosaur and fueling speculation that it could very well be a descendant of the animal. Modern research has also found that Plesiosaur remains have been discovered in ancient riverbeds, indicating that some may have lived in freshwater environments (such as Loch Ness) where previously they were thought to only reside in saltwater. In any event, the legend of Loch Ness has provided an entry point for the continued exploration and education of Plesiosaur and prehistory.    


O’Keefe, F. R. & Chiappe, L.M. 2011. "Viviparity and K-selected life history in a Mesozoic marine reptile". In: Science, 333, 870-873.