Master of water control!
My scientist discovered the oldest three-pointed fish more than 400 million years ago
Our reporter Lu Chengkuan
On August 2, the reporter learned from the Institute of Vertebrate Paleontology and Paleoanthropology of the Chinese Academy of Sciences that its researchers discovered the oldest tricuspid fish 419 million years ago in Qujing, Yunnan.
The fish was discovered in the Xishancun Formation of the Lohokovian in the Early Devonian about 419 million years ago. It was named Liu's Sicklefish. It is a new genus of armored fish, Tricuspidae, and it is currently known. The oldest member of the tricuspidae.
Related research results were published online in the international academic journal "Historical Biology".
The name of the genus Liu's Sicklefish indicates that its horns and inner horns are combined into a sickle shape, and the species name is dedicated to the discoverer of the fossil and the first person to study armored fish-Mr. Liu Yuhai.
"Its discovery enriches the morphological characteristics of the tricuspidae, and provides key materials for exploring the adaptive radiation of armored fish in the Lohokoffian of the Early Devonian. At the same time, it is useful for studying the origin and diversity of tricuspidae. And paleogeographical distribution, as well as exploring the morphological function of armored fish horns and anastomoses are also of great significance." said the corresponding author of the paper and associate researcher of the Institute of Paleospine, Chinese Academy of Sciences, Gai Zhikun.
Sickle-horned fish belong to the subclass of jawless armored fish in the broad classification. There is only one relatively complete fossil at present, which was discovered by Mr. Liu Yuhai during a field investigation in Qujing, known as the "Kingdom of Ancient Fish" in the 1980s. .
Armored fishes are a type of extinct armored fishes with "helmet and armor". They are currently only found in the Silurian-Devonian strata in China and northern Vietnam. They have a strong indigenous color.
Gai Zhikun said that as a branch of the jawed group, the study of armored fish can help us understand the evolution of the key characteristics of jaws.
Tripointed fishes belong to the order of the Armorfish subclass True armored fishes. It was originally discovered in Dalle Town, Xiangzhou County, Guangxi Province. It is due to the type species Bigeye Tripointed fish with a pointed snout and a pair of laterally extending sharp horns. Named after.
Gai Zhikun emphasized that the tricuspididae is a relatively specialized group in the order True Armorfish, which is of great significance to our understanding of the radiation evolution and ecological diversity of Armorfish in the Early Devonian.
The results of phylogenetic analysis showed that Sickle-horned fish, Winged-horned fish and Tri-pointed fish together formed a single line-Tri-pointed fish family.
The obvious snout angle and the sickle shape of the angle and the inner angle of the sickle fish can be used as important distinguishing characteristics of the tricuspidae.
Traditional morphological analysis believes that armored fishes are benthic fishes with weak swimming ability. Therefore, there are also many disputes about the morphological functions of the anastomoses and horns.
Different paleontologists have different explanations for the functions of these different forms of head carapace protrusions, such as maintaining the balance of the fish body, predation aids similar to shovel that stirs food on the bottom of the sea, special sensory organs, and ship anchors. Fixed effects, and increased body size to deter predators, etc., vary.
Hydrodynamic analysis based on armored fish shows that the laterally extending wing angles of the head armor may increase their lift in the water when water flows, similar to the ground effect of an airplane wing during takeoff.
This kind of lift is essential for armored fishes that wear thick armor and lack double fins. It can well overcome its own gravity and achieve more efficient cruises.
Gai Zhikun said that this indicates that some armored fishes may be active swimmers like bony armored fishes. Although they do not have double fins, they can adopt more various sports strategies to well manipulate the surrounding head armor. Water flow to achieve higher mobility and flexibility.
(Science and Technology Daily, Beijing, August 2nd)