Chinese palaeontologists identify new shrimp species

NANJING -- Chinese palaeontologists have established a new species of a shrimp fossil unearthed in Southwest China's Yunnan province, dating back 518 million years.

The new species, Innovatiocaris maotianshanensis, was formerly known as an Anomalocaris, meaning abnormal shrimp, as its appearance is quite similar to the already known radiodont, according to the Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences.

The fossil of the new shrimp species was collected from the early Cambrian fauna of the Chengjiang sedimentary deposit in Maotianshan Mountain.

Similar to Anomalocaris, it has a streamlined trunk with paired paddle-like blades and gill flaps for swimming and breathing, a pair of spiny pincers and a pair of large compound eyes on the head, and radial mouthparts beneath the head, said Zeng Han, associate researcher of the institute.

However, I.maotianshanensis has a pair of particularly elongated tail forks, and the morphological details of its front claws are distinctly different from those of Anomalocaris, said Zeng.

Researchers have also conducted an evolutionary analysis of the genus, which indicated that it is already very close to the evolutionary starting point of Anomalocaris, said Zhao Fangchen, who led the study.

Zhao added that the discovery also provides important clues for understanding the evolution and ecology of early euarthropods during the early Cambrian period.

The study was published in the Journal of the Geological Society in December 2022.