The Yunnan-Guizhou region was once an ocean. Did the maritime overlord "make its fortune" from here?

China's Yunnan and Guizhou regions were once mostly submerged by the ocean. The unique environment and geological structure make the Yunnan and Guizhou regions a recognized fossil producing area. The Panxian and Luoping faunas are famous for their rich fossil species, good preservation, and high degree of differentiation.

The Panxian fauna in Guizhou and the Luoping fauna in Yunnan both lived in the Middle Triassic. Although there are some differences in their composition and morphological types, the biodiversity composition of marine reptiles in their faunal communities is relatively similar at the family level, so they are often referred to as the Panxian-Luoping fauna .

The Panxian-Luoping fauna also marks the full recovery of the marine ecosystem in the Middle Triassic, proving the process of rapid differentiation and radiation of the ecosystem in the Middle Triassic.

The Panxian fauna is considered to be one of the oldest marine reptile communities in the world in the Middle Triassic. Its biological community is mostly composed of groups adapted to near-shore shallow water environments, and it has very important scientific research significance for the study of the evolution of Triassic marine reptiles.

The Panxian ichthyosaur fossil is one of the most representative marine reptiles in the Panxian fauna. It is the most abundant and well-preserved. It is believed by many scientists to be the oldest primitive ichthyosaur known to date. It can serve as a key link in how the primitive ichthyosaur of the Early Triassic grew step by step into the overlord of the Mesozoic ocean. It can also provide strong evidence for the study of the relationship between the evolution of ichthyosaurs and the ancient marine environment and ancient geographical changes to a certain extent.

Compared with the Panxian fauna, the abundance and diversity of fish and arthropods in the Luoping fauna are significantly higher than those in the Panxian fauna. A large number of Triassic fish fossils were first discovered, and then a large number of marine reptiles, arthropods, etc. fossils were discovered one after another. Arthropods mainly dominated, and the fish species were also rich and diverse, including Nelson's winged cod, Luoping strong fish, high-back Luoxiong fish, etc. in the collection of the National Museum of Marine Life.

Fishes such as Nelson's winged cod are all ray-finned fish that lived in the Triassic period. Nelson's winged cod is relatively rare in the Luoping fauna. Its discovery also represents the first discovery of winged cod in Asia. As the latest representative of the genus, its discovery shows that the genus continued until at least the early Middle Triassic before it became extinct.

Luoping Strongfish is one of the largest bony fishes found in the Luoping fauna. Its body length can reach 40 cm. It is the largest bony fish found in the Middle Triassic in the world.

The high-backed mullet, as the name suggests, has a body outline that is approximately triangular, with a high bulge on the back before the dorsal fin.

Overall, the Panxian-Luoping faunas are representative biological communities that represent the Middle Triassic biological recovery and have important scientific research significance.