Existing unprotected turtle species

Maoming unguarded turtle: it belongs to the hidden-necked turtle. The cutin shield on the crustacean often degenerates, and the posterior leaves of the marginal plate and abdominal nail atrophy. Live in fresh water. Some do have heads, but not many. I haven't seen the limbs so far, but many of them have preserved some broken limbs. The best material for unguarded turtles should be Germany. The perfect shell, skull, limbs and even the smallest coccyx are well preserved. 1In July, 983, a turtle named Maoming was discovered in China by Japan. Keiichi Ono, a paleontologist from the National Science Museum of Japan and the Japanese Institute of Natural History, wrote to the author, attaching a photo of the back and abdomen of a fossil turtle. The letter said that he believed the turtle was a Maoming turtle, and asked the author to verify it. After observation and comparison, the author gives a positive answer. Maoming is a city in the south of Guangdong Province. In Datang area of Jintang, this city, a set of oil shale strata is exposed, which is an oil refining mining area, and the age is in the late Eocene, about 40 million years ago. There have been fossils of Maoming turtle, oil Malay crocodile and fish, among which Maoming turtle is the most abundant. 1958, when the author went to this area for investigation, he collected more than 20 pieces of Maoming turtle fossils at one time. The scientific name of Maoming turtle is Anos-teira maomingensis, which means an-, no, no in Greek; The name "Maoming boneless turtle" is obviously unreasonable, because turtles can't be boneless. The biggest difference between Maoming turtle and other ordinary turtles in the structure of its carapace is that it has no horny shield, and its carapace only consists of a bone plate. Therefore, the original meaning of Latin word is no shield. The author translated it as "Maoming turtle without shield", referred to as Maoming turtle for short. This kind of translation is widely adopted by domestic scholars. The unguarded turtle is an extinct genus, belonging to cryptocephala, Trionychus. It lived in Paleocene-Oligocene (70-30 million years ago) and has fossils in Europe, North America, North Africa and East Asia. In addition to Maoming species, there are unguarded turtles in Mongolia, Manchuria, Lingnan and Shandong. It can be seen that this turtle was widely distributed in China at that time. The shield-free turtle is a freshwater turtle. It can't cross the ocean. How can it cross to Japan? It was explained that the Japanese island where the turtle lived at that time was connected with Chinese mainland, so the shield-free turtle living in fresh water was naturally free to come and go. Later, the island drifted away, and it is possible to find the same unguarded turtle in both places. Here, vertebrate fossils provide scientific evidence for paleogeography (Figure 43). By the way, it is often reported: "Because this fossil was found in ×× (place name), it is called ×× dragon (or ×× beast, ×××× turtle), which is incorrect. If you press this button, the unguarded turtle found in Japan this time should be called "unguarded Japanese turtle" or other names, not Maoming turtle. This violates the transcendental law in biological nomenclature, resulting in the confusion of "the same thing with different names". The correct way should be: if the structural characteristics of the later discovered organism are the same as those of the known species, it should be classified as a known species, which is also called the name of the known species, regardless of whether the known species is found at home or abroad, or whether it is named by its characteristics, name or place name. This time, Japanese scholars classified the turtle fossils found in China as Maoming turtles in China, which is the reason. In fact, at this time, the word "Maoming" did not represent a place name in China, but became a specific name in paleontology. Just like someone named "Nanjing" in our country, he is not necessarily from Nanjing.