Caseids first appear in the fossil record at the end of the Carboniferous and are already present in both North America and Europe with small predatory forms like Eocasea and Datheosaurus. These faunivorous caseids also exist at the beginning of the lower Permian, such as Callibrachion, and may have existed until the base of the middle Permian with Phreatophasma.
Caseids first appear in the fossil record at the end of the Carboniferous and are found in both North America and Europe. Small predatory forms like Eocasea and Datheosaurus exist alongside them. These faunivorous caseids also appeared early in the lower Permian, such as Callibrachion, potentially continuing until the base of the middle Permian with Phreatophasma.