Horseshoe crabs live in the shallow coastal waters and near the estuary delta, and are mainly mobile benthos, which may be the most ferocious carnivorous invertebrate at that time. At that time, early vertebrates such as jaws were no match for it. Carboniferous and Permian species are mostly found in coastal coal swamp environment. Fossils have been found in Europe, Asia, North America and other places, and also in China. This paper reports the Carboniferous dermatoptera in Tangshan and the juvenile platyptera in the Three Gorges of the Yangtze River.