Extraordinary Fossil in the Collections of the Regional Museum in Most

Exhibit of the Month 4 / 2017

Extraordinary Fossil in the Collections of the Regional Museum in Most

In 2011, among the yet unclassified samples of geological collections of the Regional Museum in Most, an extraordinary fossil was discovered. On one piece of limestone, distinct, partially damaged bones were visible. After consulting with RNDr. Boris Ekrt, the curator of the vertebrate collection of the paleontological department of the National Museum in Prague, a sensational discovery was made.

The bones on the piece of rock were identified by RNDr. B. Ekrt as bony elements of the fin of a marine reptile of the genus Plesiosaurus. The fossil was discovered before 1889 in a limestone quarry near the village of Lahošť, not far from Duchcov. At the turn of the 19th and 20th centuries, the find was studied by the prominent paleontologist Antonín Frič. He classified it into the group of predatory marine reptiles, to the species "Hunosaurus fasseli". At this time, he also created a plaster cast, which is stored in the National Museum. The cast significantly helped to identify the find, which had been considered lost for decades.

The "rediscovered" unique specimen is not complete, as its part with one bone element, which is marked with the number Ob 00047 on Frič's cast, has not been found. During the geological period of the Cretaceous (approximately 145 to 66 million years ago), a large part of the territory of Bohemia was covered by a warm, shallow sea. The Cretaceous sea was rich in marine sponges, cephalopods, crustaceans, echinoderms, fish, sharks, and many other species of fauna and flora. The abundance of Cretaceous marine fauna likely caused some terrestrial reptiles to return to the aquatic environment in search of food. Some species of Cretaceous reptiles, such as the genus Mosasaurus, grew to lengths of up to 10-12 meters. Our Lahošť "lizard" was a tiny creature compared to them, measuring around two meters.

The fossil is one of the few rare finds of marine reptiles from the Mesozoic era in the territory of the Czech Republic. Its age is about 90 million years.

In the newly planned natural science exhibition of the Regional Museum in Most, this exceptional fossil will have a significant place. Museum worker Ing. Jaroslav Bažant created a life-size model for the presentation of this unique specimen.