[1] Their fossil remains date to the Cretaceous period (144 - 66.4 MYA).

Its child geniuses are Acanthechinopsis, Acrocidaris, Acrotiaris and Aplodiadema.

The distribution of fossils in the Cretaceous are in Algeria, Brazil, Egypt, France, Hungary, Jordan, Madagascar, Morocco, Nigeria, Peru, Portugal, Saudi Arabia, Spain, Switzerland, the United Arab Emirates, the United Kingdom, United States (Texas), and Yemen.

In the Jurassic found in Ethiopia, France, Germany, India, Luxembourg, Morocco, Poland, Portugal, Saudi Arabia, Somalia, Switzerland, and the United Kingdom.

[2] The full fossil reference needs translation into English.