Source: China News Network
BEIJING, Oct. 26 (Xinhua) -- The latest research team of Xu Guanghui of the Institute of Vertebrate Paleontology and Paleoanthropology of the Chinese Academy of Sciences (Institute of Paleovertebrates of the Chinese Academy of Sciences) on three 244 million-year-old ancient fish fossils collected from the Triassic marine strata of Luoping, Yunnan Province, has found that they are the oldest ribbed schizocephalic fish known in the world, and the earliest discovery record of ribbed schizocephalic fish has been advanced by about 2 million years. It was also the first discovery of the fish in Asia, hence the name Asian ribbed schizocephalus.
Researcher Xu Guanghui presents a 244 million-year-old fossil specimen of the Asian rib-scaled schizocephalus. Photo by Sun Zifa, a reporter from China News Service
Xu Guanghui, a researcher, said in an interview with the China News Agency reporter in Beijing on the 26th that the name of the ribbed tooth fish comes from its transition state from the split tooth fish to the ribbed fish. The Asian ribbed toothfish found in this study is a rare species in the Luoping biota 244 million years ago, the research team spent more than 10 years in Luoping field research sampling, so far only found 3 fossils of this ancient fish species, fortunately they are very well preserved, can completely restore their morphological characteristics, for the study of ribbed toothfish skeletal morphology and phylogenetic relationship provides important information.
A total of three fossil specimens of the 244 million-year-old Asian ribbed toothfish have been found so far. Photo by Sun Zifa, a reporter from China News Service
He said stratigraphic studies of the ribbed squamous fish chronological studies show that the Asian ribbed schizocephalus is about 244 million years old, 2 million years earlier than the previously found in Europe, thus renewing people's understanding of the origin of the ribbed toothfish family and the recovery of Triassic marine life. The research results have been published online by the latest issue of the international professional academic journal PeerJ.
Enlarged view of the head of a regular specimen of the Asian ribbed schizocephalus. Photo courtesy of Xu Guanghui
According to the Institute of Paleovertebrates of the Chinese Academy of Sciences, about 250 million years ago, the most catastrophic end-Permian mass extinction event occurred in the history of life on Earth. In order to understand the subsequent Triassic ecological reconstruction, Xu Guanghui's research team has conducted continuous research on the Triassic marine strata in Yunnan-Guizhou region of China for more than 10 years, and has discovered and named 21 aquatic vertebrate fossils.
Xu Guanghui said that the Asian ribbed schizocephalic fish named in this study is a small carnivorous fish living in shallow seas, which can eat some small invertebrates with hard shells such as shrimp, and its characteristics include 3 columns of higher scales in the front of the body, and a prominent posterior spine on the abdomen of the proximal dorsal scales, while the European counterpart has only 2 rows of higher scales in the front of the body.
Orthotype specimen and restoration of the Asian rib-scaled schizoty-toothed fish. Photo courtesy of Xu Guanghui
The ribbed schizocephalus is a representative species of the new fin fish trunk during the recovery period of central Triassic marine organisms, and the earliest fossil record was found in the marine strata of Italy and Switzerland 242 million years ago, and the asian ribbed toothfish was found to advance the earliest record of the discovery of the ribbed squamous fish by about 2 million years, increasing the academic understanding of the biogeography of the ribbed squamous fish.
Researcher Xu Guanghui introduced the research results of the Asian ribbed toothfish 244 million years ago. Photo by Sun Zifa, a reporter from China News Service
He pointed out that because the ribbed schizocephalic fish have the transitional characteristics of both ribbed and schizocephalic fish, their taxonomic location is difficult to determine. Based on the detailed comparison and branching systematics of eurasian ribbed toothfish, the latest study proposes for the first time that the ribbed squamous fish is a sister group of leaky fish, and newly establishes the ribbed tooth fish family and classifies it into the order Ofhopods. "This study solves the taxonomic problem of ribbed schizocephalus and is also important for understanding the early evolution and biogeography of Triassic neofinfish." (End)