The "Time Cinema" of the dinosaur era, this is Lufeng, Yunnan!

The discovery of the Lufeng ancient vertebrate fauna plays a very important role in the evolution of vertebrates. The most obvious feature of the evolution of vertebrates to the Mesozoic era is that reptiles represented by dinosaurs replaced the amphibians hidden in the late Paleozoic era, completing the evolution of vertebrates from amphibious to completely terrestrial. Therefore, we often call the Mesozoic era the "Age of Reptiles" and the "Age of Dinosaurs". The Lufeng dinosaurs are at the early node of the "Age of Dinosaurs". Therefore, they have obvious advantages and important positions in the history of vertebrate evolution and are unique in the world's dinosaur culture. Mesozoic dinosaurs in the scientific sense actually refer to the two major categories of reptiles, namely sauropods and ornithopods. After the appearance of the two, they soon parted ways and differentiated rapidly in their own different directions. In the Lufeng area, before they parted ways, there was a brief "honeymoon period" of symbiosis between the two. In other words, the two types of dinosaurs were found to coexist in the Lufeng area: the prosauropod dinosaurs Lufengosaurus, Yunnanosaurus, Sinosauropterygian, and Lugousaurus coexisted with the ornithischian dinosaurs Dadilong, Dawasaurus, and Dianzhongsaurus. Detailed research on the two types of dinosaur fossils can not only restore the survival struggle between herbivorous dinosaurs (sauriformes) and carnivorous dinosaurs (ornithischians), which was both symbiotic and competitive, but also explore the reasons and ways for the two to part ways and evolve in their own unique directions.

1. Xu's Lufengosaurus

Description of the fossil morphology of Lufengosaurus xu. Lufengosaurus xu is one of the most representative dinosaurs in Lufeng area. It belongs to the prosauropod herbivorous dinosaur and lived in the early Jurassic period. It was first discovered in the Jurassic Lufeng Formation in Shawan, Lufeng in 1938 by Bian Meinian, Yang Zhongjian and others. It is known as the "first dragon in China". It is of medium size, about 4.5 to 6 meters long, with a small and not very elongated skull, large round eye sockets, a strong tail, and the first fingers (or toes) of the hands and feet are particularly developed. There are at least 25 teeth in the upper and lower parts of the mouth. These teeth are similar in shape to leaves, with tiny serrations on the front and back edges. Generally speaking, Lufengosaurus xu has 9 cervical vertebrae, 14 dorsal cones, 3 sacral vertebrae, 38 to 48 caudal vertebrae, 24 venous arcs, and can walk upright.

After leaving Yunnan, Bian Meinian recorded what he saw and heard and published an article titled "The Excavation of Dinosaurs in Lufeng, Yunnan" in the Ta Kung Pao in 1939, leaving us precious historical data.

Lufengosaurus xu belongs to: Sauropoda, Saurischia, Sauropodomorpha, Massospondylidae, Lufengosaurus

Figure 1: Xu's Lufengosaurus group (Source: Lufeng Dinosaur National Geopark Promotional Atlas)

2. Giant Lufengosaurus

The giant Lufengosaurus is a herbivorous dinosaur of the prosauropod family. It lived in the early Jurassic period. Its fossils were found in the Jurassic Lufeng Formation in Lufeng. It is one-third larger than Lufengosaurus xusii and heavier. It is about 9 meters long and 4 meters high. It has 9 cervical vertebrae, 14 dorsal cones, 3 sacral vertebrae, 38 to 48 caudal vertebrae, and 24 arcs. Its hind legs are strong and it can walk upright. Compared with its hind limbs, its forelimbs are quite short and its vertebrae are thick. Its talus is very slender in the horizontal direction, and is thicker than that of Lufengosaurus xusii. The difference in size is also very large.

The giant Lufengosaurus belongs to: Sauropoda, Saurischia, Sauropodomorpha, Massospondylidae, Lufengosaurus

Figure 2: Group of images of giant Lufengosaurs (Source: Lufeng Dinosaur National Geopark Promotional Atlas)

(3) Xinwa Jinshanosaurus

Xinwa Jinshanosaurus is a giant prosauropod omnivorous dinosaur that lived in the early Jurassic period. Its fossils were found in the Jurassic Lufeng Formation in the Lufeng Basin. It is about 8.6 meters long and 4.2 meters tall. It has heavy and strong bones, a relatively small skull, and a head length of 37.5 centimeters. It has a long dentition and a large number of teeth. It has short forelimbs and walks on its hind limbs most of the time. Xinwa Jinshanosaurus has a strong femur, thick limb bone walls, and short forefoot bones.

Figure 3: Xinwa Jinshanosaur Group (Source: Lufeng Dinosaur National Geopark Promotional Atlas)

(IV) Anagawa Street Dragon

Anachuanjiesaurus is a herbivorous sauropod dinosaur that lived in the Middle Jurassic. Its fossils were first discovered in the Chuanjie Formation of the Jurassic System in the Chuanjie Basin. It is about 27 meters long and 6.5 meters tall. It is huge, with a long neck and tail, and a very small skull.

Ana Chuanjiesaurus is one of the most representative dinosaurs in Lufeng. It was found in the Chuanjie Formation in Ana Village, Dinosaur Mountain Town, Lufeng City. It was discovered by a farmer while working in his own field. Because he had heard about the dinosaur fossil display activities organized by Lufeng City and had a certain understanding of dinosaur fossils, he took the fossil to the Lufeng Dinosaur Museum at that time for experts to identify it. After confirming that it was a dinosaur fossil, Lufeng carried out a larger-scale on-site exploration activity, and then discovered the world-renowned "Yunnan Chuanjie Dragon Turtle Tomb", which set off another climax in Lufeng dinosaur research. Through preliminary excavation, the "dinosaur cemetery" at the level of the dinosaur fauna in Laochangqing, Chuanjie was found. In addition, the "Lufeng Sauropoda Fauna", "Chuanjie Dinosaurosaur Fauna" and "Yunnan Mamenchisaurus Fauna" representing the Early, Middle and Late Jurassic were discovered on the unified section of the Chuanjie area. They are rare at home and abroad and are a new breakthrough in the study of Jurassic stratigraphic paleontology.

Anachuanjiesaurus belongs to the suborder Sauropoda

Figure 4: Anachan Street Dragon Group (Source: Lufeng Dinosaur National Geopark Promotional Atlas)

5. Diplodocus sinensis

Diplodocus sinensis is a carnivorous theropod dinosaur, the top predator in the ecosystem at that time, living in the early Jurassic period, and its fossils were found in the Jurassic Lufeng Formation in the Lufeng Basin. It is about 6 meters long and 2.4 meters high, with a large skull, short forelimbs, good at running, and two large bone crowns on its head, so it is named "Diplodocus".

Sinosaurus belongs to: Saurischia, Theropoda, Neotheropoda

Figure 5: Chinese Diplodocus group (Source: Lufeng Dinosaur National Geopark brochure)

(6) Triassic Chinese Dragon

Sinosaurus triassic, a theropod of Sinosaurus triassic. It was first studied by Yang Zhongjian, a pioneer in Chinese dinosaur research, who published a paper in 1948 and named this dinosaur Sinosaurus triassic. However, due to the fragmentation of the specimen, which only has a jawbone and three teeth, we know very little about the specific situation of this dinosaur.

On March 24, 2023, an article published in the British Journal of Historical Biology systematically introduced the characteristics of the Triassic Sinosaur and compared it with the Chinese Diplodocus specimens found in Jinning and Shuangbai, Yunnan. It was found that there were several differences between the two types of dinosaurs, proving that the Triassic Sinosaur was an independent type of dinosaur. This paper was jointly researched and published by Zhang Zechuan and You Hailu from the Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences, and Wang Tao from the Dinosaur Fossil Protection and Research Center of Lufeng Municipal Natural Resources Bureau. The three newly discovered features are considered to be unique to this species: one is the vertical ridge that develops from the ventral side of the maxilla to the dorsal and ventral side of the nasal ridge, the second is that the ventral boundary of the preorbital window is mainly formed by the anterior process of the neck, and the third is the window between the nose, lacrimal gland and prefrontal lobe.

Figure 6: Triassic Sinosaur skull fossil

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7. Pangeraptor

In 2014, the journal Zootaxa published a paper on Pancharaptor published by You Hailu, Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences, which officially made the research results of the fossil public to the world. As the only coelophysis dinosaur discovered in Asia, the Pancharaptor specimen preserves a relatively complete head and postcranial skeleton, with a body length of about 2 meters and a height of about 0.5 meters. It was probably close to an adult individual when it died. The specimen is small in size, with a skull length of 11.1 cm, a maxillary snout to the ventral end of 11.1 cm, a presacral spine length of about 58 cm (trunk to neck length ratio of about 1.3), a shoulder blade length of 8.6 cm, a femur length of 16.4 cm, and a tibia length of 18.2 cm. Early theropod dinosaurs usually had a long tail that accounted for more than half of the total body length, which means that this dinosaur may have been about 2 meters long when it died. The height of the hips is about half a meter.

2 Pancharaptor belongs to: Theropoda, Coelophysis, Pancharaptor

Figure 7: Photo of Panguraptor fossil (Source: You Hailu's 2014 paper)

8. Golden Age Dragon

The first systematic introduction to Jinshidaisaurus was published in a paper by Wu Xiaochun, Philip J. Ali, Dong Zhiming, Pan Shigang, Wang Tao, and others in 2009. Jinshidaisaurus is characterized by the occipital process excluding the supraoccipital process from the foramen magnum, the lateral occipital process slightly tilted downward (about 110 degrees from vertical), the sharp epiphysis and the thin axis between the neural crest, which is wider than that of other theropod dinosaurs; the length of the pubis from the ventral to the posterior part is almost the same as that of the ilium; the lack of a ventral notch distal to the obturator foramen on the sciatic bone; and a relatively long ischium (more than 96% of the length of the stock).

Golden Age Dragon belongs to: Theropoda

(9) Cheng’s Xingxiu Dragon

The first paper on Cheng's Xingxiusaurus was published in Science in 2017 by Wang Yaming, You Hailu, Wang Tao and others. Cheng's Xingxiusaurus was a medium-sized sauropod with a unique combination of the following characteristic states: both horns and horns, relative to the external mandibular membrane foramen; a laterally expanded plate-like roof on the top of the posterior vertebra (converging in basal sauropods); four sacrums, two primitive sacrums consisting of a dorsal sacrum and a coccygeal sacrum (converging in derived sauropods); a robust scapula with extremely expanded ends; a strongly concave ventral margin of the posterior acetabular process of the iliac acetabulum; an elongated pubic plate proximally relative to the pubic apron, which is about 40% of the total pubic length (converging in basal sauropods); a narrower posterolateral process of the distal tibia and extending more laterally distally than the anterolateral process; a median elevation on the posterior margin of the astragalus; and a strongly expanded proximal metatarsal V with a proximal width/total length ratio of 0.85.

Figure 9: Cheng's Xingxiusaurus fossil (Source: 2017 Science magazine "A new basal sauropodiform dinosaur from the Lower Jurassic of Yunnan Province, China")

(10) Sun's Yizhou Dragon

In 2018, a paper on Sun's Yizhousaurus was first published in the journal Science by Zhang Qiannan, You Hailu, Wang Tao and others. Both nasal bones in the fossil specimen's skull are long and narrow, but their posterior parts are fractured, with a large hole penetrating the center of the skull top. Each nasal part produces two processes, the anterior ventral process is very short, and extends ventrally for a limited distance along the ascending process of the maxilla, which is different from the case of most non-sauropods, in which this process reaches about halfway along the ascending process of the maxilla. The ventral keel develops on the first three dorsal parts, but gradually disappears posteriorly. The ventral keel develops on the first three dorsal parts, but gradually disappears posteriorly. The first three dorsal neural spines have a laterally widened dorsal crest, a feature present in other Lufeng specimens, including Yunnanosaurus.

Figure 10: Sun's Yizhou dragon skull fossil (Source: 2018 Science magazine "A new sauropodiform dinosaur with a 'sauropodan' skull from the Lower Jurassic Lufeng Formation of Yunnan Province, China")