J507 - Museum Grade Rare Jeholotriton paradoxus - Primitive Jurassic Salamander - Daohugou Beds

Jeholotriton is a genus of primitive, neotenic (retaining larval features) salamanders from the Middle/Late Jurassic (approx. 164–155 Ma) of Inner Mongolia, China. Found in the Daohugou Beds, it is a key fossil for early urodele evolution, with specimens often showing well-preserved, soft-tissue impressions, short limbs, and 16-17 presacral vertebrae. 

Key Details of Jeholotriton paradoxus:

Age and Location: Primarily found in the Daohugou Bed, which is considered late Middle Jurassic to early Late Jurassic, not the Early Cretaceous as previously thought. 

Link to info about Tiaojishan Formation: Tiaojishan Formation

Characteristics: It is a small salamander with a distinctively shaped "paradoxical" skull, from which it derives its species name, J. paradoxus. It shows paedomorphic features (retaining juvenile traits into adulthood), such as larval-like skull structure and unossified carpal/tarsal elements.

Diet: Studies of fossilized guts show that Jeholotriton (along with Chunerpeton) fed on aquatic, invertebrate prey such as juvenile conchostracans (Euestheria luanpingensis), indicating a specialized, lacustrine (lake-dwelling) diet.

Evolutionary Significance: Jeholotriton is considered a member of the Cryptobranchidae family (giant salamanders) and represents a key, early branch in the evolution of modern salamanders (Urodela). 

Jeholotriton is often associated with the Jehol Biota, although the Daohugou fossils are actually older than the main Jehol fauna. 

Observations about our specimen: Our specimen, among all others, we can consider it a masterpiece. Its size is extraordinarily large in comparison with the average of this primitive salamander.

Regarding to its preservation: It is exceptional as it corresponds to a "Konservat-Lagerstätten" fossil. Coined by Adolf Seilacher in 1970, Lagerstätte means "storage place" or "site". Konservat implies high-quality preservation. Focus on quality (exceptional preservation of soft parts).
Our specimen perfectly shows the impression of all soft parts.
During the excavation of the fossil, the final slab broke into various fragments which were subsequently glued and filled, making the piece stable again. Considering these restorations in the matrix, the fossil in itself does not pose any type of restoration other than the fractures that cross it and were glued and filled.