Survival and recovery of calcareous foraminifera pursuant to the end-Permian mass extinction

Ninety-one percent of calcareous foraminiferal genera became extinct during the end-Permian mass extinction. The Early Triassic Epoch was a survival phase characterized by a short-lived proliferation of disaster forms and then a prolonged interval of low diversity. The orders Miliolida and Lagenida experienced limited taxonomic re-diversification in Early and Late Anisian time, respectively. All fusulinoidean fusulinides became extinct in Late Permian time, and only two non-fusulinoidean genera persisted into the Early Triassic. Triassic fusulinides diversified to just five genera before the order became entirely extinct in Late Triassic time. Involutinides originated in Olenekian time from an unknown ancestor. They did not significantly diversify until Late Triassic time.