Chinese Dinosaurs

Dong Zhiming. Encyclopedia of Dinosaurs. Editor: Philip J Currie & Kevin Padian. Amsterdam: Academic Press, 1997.

In the past two decades, great progress has been made in the knowledge of Chinese dinosaurs. A huge number of dinosaur skeletons, eggs, and footprints have been collected, studied, and displayed, with more than 100 species of dinosaurs, including eggs and footprints, described and named so far (Dong, 1992). The study of dinosaurs in China not only has greatly extended the list of dinosaurs over the world but also has made great contributions to the understanding of general theoretical problems concerning these fascinating animals (Russell, 1993).

A Brief History of the Study of Dinosaurs in China

The Chinese people call themselves “descendants of the dragon.” The fossilized vertebrate bones are known as “dragon bones.” For instance, as early as the Jin Dynasty (265-317 A.D.), a book titled Hua Yang Guo Zhi already recorded the discovery of dragon bones in Wuchen, which covered the present Santain County, Sichuan Province. Because most of the exposed strata belong to Jurassic deposits, it is highly probable that the bones discovered were actually dinosaur bones.

The earliest scientific discoveries of dinosaurs in China were made in the 1910s by Russians in the southern banks of the Heilongjiang (Amur) River. The finds were referred to a hadrosaur, Mandschurosaurus. It is the first named dinosaur in China (Riabinin, 1925, 1930).

In 1913-1915 an American geologist, George Louderback of the University of California at Berkeley, reported the first dinosaur fossils to be found in the Sichuan Basin (Louderback, 1935; Camp, 1935). A German mining engineer, Berhagel, found several fossils of dinosaurs in Mengyin, Shandong, in 1916. This site was excavated by an Austrian paleontologist, Zdansky, in 1922 and 1923. This was the well- known Euhelopus (Wiman, 1929).

Reports on these early discoveries of dinosaur fossils aroused the attention and interest of many Western paleontologists. A series of multinational expeditions came to China, such as the Central Asiatic Expeditions of the American Museum of Naturalhistory (1921-1930), the Sino-Swedish Expeditions (1927-1935), and Sino-French Scientific Expeditions (1930). The Central Asiatic Expedition was the largest of the three and proved to be the most fruitful (Osborn, 1924; Andrews, 1932).

The years 1933 to 1949 represent the initial stage in the study of dinosaur fossils in China. The progress accomplished during this period was mainly undertaken by Dr. C. C. Young. After pursuing his studies in Germany, he returned to China in 1928 and devoted himself to the study of paleovertebrates. From 1933 onwards, he began to focus his attention on the study of reptiles and conducted a series of excavations for dinosaur fossils in Sichuan, Yunnan, Xinjiang, and Gansu. He undertook the famous excavation at Lufeng Basin, Yunnan, in 1938 (Young, 1951).

In 1951 Dr. Young led an excavation of Late Cretaceous dinosaurs at Laiyang, Shandong, and collected a complete skeleton of Tsintaosaurus. A large sauropod skeleton, Mamenchisaurus, was studied by Young in 1954. In 1957, a new nearly complete skeleton of Mamenchisaurus was unearthed from Hechuan, Sichuan. This giant dinosaur was named M. hechuanensis and is the longest dinosaur ever discovered in Asia.

From 1959 to 1960, Sino-Soviet paleontological expeditions conducted large-scale excavations in the Erlen and Alxa Gobi areas of Inner Mongolia and obtained a sizable quantity of Early Cretaceous dinosaur fossils, which included Probactrosaurus (Iguanodontidae), Chilantaisaurus (Theropoda), and an ankylosaurian dinosaur. For political reasons, the expeditions were suspended in 1960.

From 1963 to 1966, the Institute of Vertebrate Paleontology and Paleoanthropology of Chinese Academy of Sciences organized expeditions that explored the Junggar and Turpan basins of Xinjiang for 3 years and discovered the pterosaur fauna of Urhe (Dong, 1973). Nearly simultaneously, a large hadrosaur skeleton was found in Shandong. It was named Shantungosaurus, measuring 15 m in length. In 1974, 106 crates of dinosaur fossils weighing more than 10 tons were collected by the Chongqing Museum from the Late Jurassic of Zigong area. These finds include two skeletons of Omeisaurus, one skeleton of Szechuanosaurus, and Tuojiangosaurus (Dong et al., 1983). In an attempt to fill in the gaps in the evolution of dinosaurs, Chinese paleontologists engaged in the study of dinosaurs have focused on the Early and Middle Jurassic strata. They began by exploring Yunnan, Guizhou, Sichuan, and the eastern part of Xizang (Tibet) from 1976 to 1979. They found Middle Jurassic sauropods, theropods, and stegosaurs (Dong, 1992).

In 1976, a large, incomplete skeleton of a sauropod was collected from the Xiashaximiao (Lower Shaximiao) Formation of the Middle Jurassic in Dashanpu of Zigong City. This specimen was named Shunosaurus lii (Dong et al., 1983). Now this site has become the well-known Dashanpu Dinosaur Quarry.

From May 1979 to July 1981, the author led the dinosaur excavations in the Dashanpu dinosaur quarry. More than 40 tons of dinosaur fossils were uncovered by the Institute of Vertebrate Paleontology and Paleoanthropology, the Chongqing Municipal Museum, and the Zigong Salt Industry History Museum. Approximately 8000 bones have been excavated, many of them large and some articulated as skeletons. The fossils include complete skeletons of sauropods(Shunosaurus, Omeisaurus, and Datousaurus), carnosaurs (Gasosaurus), stegosaurs (Huayangosaurus), ornithopods (Agilisaurus and Xiaosaurus), pterosaurs, a plesiosaur, amphibians, and fishes. They represent more than 100 individual animals and include at least 12 reptiles, including 6 different kinds of dinosaurs. From July 1981 to May 1982, this quarry was worked by a Sichuan expedition.

Dashanpu Quarry has proved to be one of the richest and most rewarding localities for Middle Jurassic dinosaurs in the world. The Zigong Dinosaur Museum was built on the site and opened in the spring of 1987. An outstanding feature of this magnificent museum is that it was erected over the stratum containing the dinosaur skeletons.

The newly reformed, open politics of China welcome foreign scholars to cooperate with Chinese colleagues. Some projects were in cooperation with the British Museum of Natural History (1982), Texas Tech University (1985), and Canada (1986-1990). The most exciting finds were made by the China-Canadian Dinosaur Project (CCDP) from 1986 to 1990.

In 1986, a dinosaur project, the CCDP was organized. This is the first joint paleontological expedition into the northwestern interior of China since the 1940s (Dong et al., 1988, 1989; Currie, 1991). The main aim of CCDP is to study Mesozoic continental strata in the north part of China, to find superb dinosaur fossils, and to trace the relationships among various groups of dinosaurs of Asia and North America. Fieldwork has been carried out in the Junggar Basin of Xinjiang, the Gobi Desert of Inner Mongolia, and the badlands of Alberta and the Arctic islands of Canada. Two special issues of the Canadian Journal of Earth Sciences were published as the scientific results of CCDP. Eight new genera and 11 new species of turtles and dinosaurs were described in these special issues. A traveling exhibition, “Dinosaur World Tour,” was displayed in several countries.

From 1992 to 1993, an expedition from the Institute of Vertebrate Paleontology and Paleoanthropology (IVPP) explored for dinosaurs along an ancient silk road. A new dinosaur site from the Early Cretaceous was found in the Mazunshan area, Gansu. Many dinosaur fossils, including iguanodontids, sauropods, and primitive protoceratopsids, were collected.

Distribution and Biostratigraphy of Chinese Dinosaurs

China has excellent outcrops yielding dinosaur remains. Rocks deposited during the lifetime of the dinosaurs were laid down on low plains and in basins by rivers and lakes. This was important for the preservation of the remains of land vertebrates. The current climate and topography is such that the rocks at many of the best dinosaur sites are not deeply covered with soil or concealed under thick vegetation. This allows the discovery and excavation of dinosaur bones.

Chinese dinosaur fossils can be divided into five dinosaur faunas and provide an almost unbroken record from the Late Triassic to the Late Cretaceous periods (Dong, 1980, 1992):

  1. Early Jurassic, Prosauropod-Lufengosaurus fauna
  2. Middle Jurassic (Bathonian-Callovian), Sauropod-Shunosaurus fauna
  3. Late Jurassic, Sauropod-Mamenchisaurus fauna
  4. Early Cretaceous, Psittacosaur-Pterosaur fauna
  5. Late Cretaceous, Hadrosaurid-Titanosaurid fauna

The Early Jurassic Lufengosaurus Fauna

This period is a significant time in dinosaur evolution. Dinosaurs were extensively distributed throughout all the continents. This cosmopolitan fauna could be named the Circum-Tethys Dinosaur Fauna (Dong, 1983). In China, this dinosaur assemblage comes mainly from southern China, such as the Lufeng and Yimen basins of Yunnan; the Weiyuan Basin of Sichuan, and the Dafang Basin of Guinzhou. So far, 23 genera of vertebrates have been recorded from the Lower Lufeng Formation. It represents what is here termed the prosauropod-Lufengosaurus faunal complex (Dong, 1980, 1992; Zhen et al., 1985). Representative dinosaurian taxa include three genera of prosauropods, Lufengosaurus, Anchisaurus (Gyposaurus), and Yunnanosaurus; theropods (Lukosaurus, Sinosaurus, and Dilophosaurus); a stegosaur (Tatisaurus); and small ornithopods (Dianchungosaurus) (Young, 1941, 1942, 1951).

Kunmingosaurus wudingensis was a primitive sauropod from the Early Jurassic of Wuding, Yunnan. Its head and lower jaw are rather deep, with spoon- shaped teeth; the sacrum consists of six vertebrae. Its pelvic girdle shows sauropod-like features, modified in the form of a plate. This dinosaur is 7.5 m long and has a relatively short neck. Its heavy body is supported by four massive and straight legs (Dong, 1992).

The discovery of Dilophosaurus in the Lower Lufeng Formation was an important find in China made by the Kunming Museum in 1986 (Wu, 1992). It provided evidence that the age of the Lower Lufeng Formation was Early Jurassic. Young (1951) argued for a Rhaetic age of the prosauropod-Lufengosaurus fauna of the Lower Lufeng Formation. It is now considered Early Jurassic in age by most paleontologists (Chen et al., 1982; Wu, 1991; Wu et al., 1993).

The Middle Jurassic Shunosaurus Fauna

The Middle Jurassic is a period when many major dinosaur taxa seemed to make their first appearances. They became the dominant members through a rapid radiation. Middle Jurassic dinosaurs in China come from two major areas: the Sichuan and the Junggar basins. In Sichuan, the Dashanpu is a well-known Middle Jurassic (Bathonian-Callovian) dinosaur site. It produced a primitive sauropod-Shunosaurus fauna from the Lower Shaximiao (Xiashaximiao) Formation. The Shunosaurus fauna contained sauropods (Protognasaurus, Shunosaurus, Datousaurus), theropods (Gasosaurus and Szechuanosaurus), a stegosaur (Huayangosaurus), and ornithopods (Xiaosaurus and Agilisaurus).

Shunosaurus, a short-necked sauropod, is the best known dinosaur, with 12 or more complete skeletons and three well-preserved skulls discovered. Omeisaurus is a large sauropod. Omeisaurus tianfuensis has a bony club at the end of the tail for defense.

Agilisaurus louderbacki was a small fabrosaurid dinosaur (Peng, 1990). The material includes a nearly complete skeleton, with a complete skull. Many remains ranging from juveniles to adults were found at the Dashanpu site.

Huayangosaurus was a rather primitive stegosaur, with six or seven small teeth on the premaxilla. The bony plates are variable in shape and are arranged symmetrically along its back from the neck to the end of the tail. A pair of large bony plates also lie on the shoulders. Twelve individuals were found at Dashanpu Quarry.

Middle Jurassic deposits are also distributed extensively in the Junggar Basin, Xinjiang. They are called the Wuciawan Formation and are composed of light gray, fine to medium-grained feldspathic quartzitic sandstones, sandy mudstones, and siltstones. The environments of deposits were fluvial to deltaic. Bellusaurus sui was a small sauropod (4.8 m). Seventeen individuals have been found from the single quarry of Konglonggou (Dinosaur ravine), Kelamaili region. Evidently a herd of these animals had been overwhelmed in a flash flood. Morphological features suggested that they could be a group of juveniles.

Monolophosaurus is an allosaurid with a well-developed ridge on the top of the head. The material is a nearly complete skeleton with a complete skull and was collected from the Wucaiwan Formation in the Jiangjunmiao site in 1984 (Zhao and Currie, 1993).

The Late Jurassic Mamenchisaurus Fauna

The Late Jurassic represents a golden age of dinosaurs. Sauropods were flourishing and became the most abundant taxon, evolving giantism during the Late Jurassic. They reached their maximum size and greatest diversity, with a nearly global distribution. Chinese records of the Late Jurassic dinosaur-bearing strata to date are mainly from the Shishugou Formation of the Junggar Basin, the Xiangtang Formation of Gansu Province, the Mengyin Formation of Shandong Province, and the Upper Shaximiao (Shangshaximiao) Formation of the Sichuan Basin.

The main dinosaur fossils yielded by the Upper Shaximiao Formation include sauropods (Mamenchisaurus and Omeisaurus), theropods (Szechuanosaurus, Yangchuanosaurus, and Sinraptor), ornithopods (Gongbusaurus and Yandusaurus), and stegosaurs (Chialingosaurus, Tuojiangosaurus, and Chungkingosaurus).

Mamenchisaurus hechuanensis is the most famous sauropod of China, known from a fairly complete skeleton lacking only the skull and forelimbs. Mamenchisaurus was placed in a family of its own. C. C. Young pointed out that the Mamenchisauridae is similar to the Diplodocidae. Recently, however, an incomplete skeleton with a nearly complete skull of Mamenchisaurus was found in Raxian County by the Municipal Museum of Chongqing and a complete lower jaw was collected by CCDP. The skull of Mamenchisaurus is tiny when compared with the enormous size of the animal. It has the spatula-like teeth instead of the pencil-like teeth of the Diplodocidae, so Mamenchisauridae is valid.

Yangchuanosaurus was an allosauroid. It is known from an almost complete skeleton that lacks only forelimbs and some caudal vertebrae. This genus has three species, Y. shangyouensis, Y. magnus, and Y. hepingensis. The latter is a large form and was collected from the same beds as the former. The material consists of a complete skull, vertebrae, pelvic girdle, and hindlimbs. Recently it was referred to Sinraptor as a new species, S. hepingensis (Currie and Zhao, 1993), in a new taxon, Sinraptoridae.

Stegosaurs are the most bizarre dinosaurs found in the Upper Shaximiao Formation. Since the first skeleton of stegosaurs was found, the bony back plates of these dinosaurs have vexed paleontologists; both their function and their arrangement are still being argued. Tuojiangosaurus’s bony plates are symmetrically arranged in pairs. This is similar to those of Kentrosaurus of eastern Africa. A pair of large and symmetrical bony plates lying on the shoulders is preserved in a new specimen collected from Heping, near Zigong, with a piece of skin also found from this specimen.

In the summer of 1987, the CCDP worked in the Jiangjunmiao region and found a lower jaw and a series of cervical vertebrae at the Shishugou Formation. It was identified as Mamenchisaurus sinocandorum, the largest sauropod in Asia (Russell and Zheng, 1993). A nearly complete allosauroid, Sinraptor, was collected from the same horizon. It was described and named S. dongi by Currie and Zhao in 1993. This is the most complete skeleton of a theropod from China.

The Early Cretaceous Psittacosaurus Fauna

In Late Mesozoic times, East Asia comprised three major blocks: Siberia, north China, and south China (Lee et al., 1987). Paleomagnetic data appear to point out that all these parts of East Asia occupied the same relative latitude in the Lower Cretaceous. The landscape in the northeastern part of Asia was dominated by a plateau, including north China, Mongolia, and southern Siberia (North China Block). It was covered with alluvial plains or some large lake basins. A river, the ancient Heilongjiang, flowed west to east on this highland, where vegetation flourished (Chen, 1977). This area formed a special ecological province where there lived an endemic dinosaur assemblage (Dong, 1992; Russell, 1993). This unique group of dinosaurs (the Psittacosaurus fauna) had evolved by the early Cretaceous in northeast Asia. Several fossil birds were found in the Early Cretaceous deposits of northeast China (Sereno et al., 1990; Hou et al., 1993). These animals are collectively known as the Psittacosaurus fauna and are found in the Qingshan Formation of Shandong, the Tugulu Group of the Junggar of Xinjiang, the Zhidan Group, the Ejinhoro Formation of Ordos, and so on. This fauna contains Psittacosaurus, theropods (Kelmayisaurus, Phaedrolosaurus, and Tugulusaurus), an iguanodontid (Probactrosaurus), a stegosaur (Wuerhosaurus), a protoceratopsid (Microceratops), and a pterosaur (Dsungaripterus).

During the Early Cretaceous Period, there were two separate dinosaur faunas in the nonmarine deposits of north and south China, which are regarded as a separate district of the biogeographic province. The Psittacosaur-Pterosaur fauna is mainly found in the northern part of China (Dong, 1993).

A dinosaur fauna from the Early Cretaceous was reported at Tebch by Bohlin in 1950. Tebch means the “black plate” in Mongolian because the black lava (basalt) that may be of the mid-Aptian age (110 + 0.52 Ma) lies on top of the hill, with a thickness of 1.5-3 m (Eberth et al., 1993). The dinosaur fauna consists of Prodeinodon sp. and Psittacosaurus mongoliensis. In the summer of 1990, this locality was reexamined by the CCDP.

Nanshiungosaurus is a most interesting dinosaur from the Nanxiong Basin and is known from an incomplete skeleton. This animal has a special pelvis that identifies it as a therizinosaur. The ilium is low, and the anterior apophysis is well developed and extends outward. The pubis is straight, and the exterior edge is thick. The ischium is thin and plate-like and the distal end expands and is fused. The age of the Nanxiong Formation was suggested as Maastrichtian.

Wannanosaurus is a small dome-headed dinosaur (pachycephalosaur), with a large supratemporal fenestra and a completely flattened cranial roof. The frontoparietal region is thick, and the external surface of the skull roof cranial bone is ornamented by small and densely distributed bony processes; the ornamentation on the temporal region is well developed.

Protoceratops was the most common dinosaur discovered from Bayan Mandahu, with 66 specimens of all sizes ranging from skull lengths of 2 cm to more than 1 m. The most important and interesting discovery at this locality was two mass graves of the ankylosaurid Pinacosaurus including 12 individual juveniles the size of small sheep. They were found in a nest, lying in their original positions covered by presumably windblown sand. Small theropods, including Velociraptorand Oviraptor, were collected, and many turtles, lizards, numerous nests of dinosaur eggs, and mammals were unearthed. In sedimentological features the beds are apparently similar to the Djadokhta Formation of Mongolia.

Dinosaur Eggs

Dinosaur eggs from the Late Cretaceous are abundant in China. At first, only simple descriptions were published based on the outer structure of the eggshell. Recent studies, mainly by Zhao and collaborators, are based on observations of the microstructure of the eggshell. Microscopic analysis of eggshells from the Late Cretaceous of China indicate that at least 12-15 dinosaur species are represented by the eggs. We have observed eggshells from the Nanxiong Basin that are unusual, indicating eggs from the end of Cretaceous that did not hatch.

The dinosaurian eggs from the Wangshi Formation of the Late Cretaceous were studied by Chow in 1951. Thereafter, Young (1953) and Zhao (1979) restudied and reclassified two groups: Spheroolithid and Elongatoolithid. These eggs were distributed in the red clays of the middle-upper part of the Wangshi Formation.