Leaiid Conchostracan Zone in Antarctica and Its Gondwana Equivalents

Abstract

Two species of conchostracans (class Crustacea) occur in the coal measures of the Ohio Range, associated with a typical Glossopteris flora. New Leaia and Cyzicus (Lioestheria) species occur in a restricted zone near the top of the stratigraphic section. The biofacies represents a swampy environment and deposition in short-lived ponds of still water under variable weather cycles. The zone compares closely with the leaiid zones in South Africa, South America, and Australia, and is assigned to the Middle-Upper Permian, specifically, Lower Beaufort age.