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The Eurydesma Fauna characterizes the Late Pennsylvanian-Permian glacial-postglacial sedimentsrecorded in several Gondwanan basins during the Late Paleozoic Ice Age (LPIA). Brachiopods, as one the mostsignificant components of this fauna, are herein analyzed along with the associated bivalves, in two key sections fromwestern and eastern Gondwana (Bonete Formation in the Sauce Grande Basin, eastern Argentina, and the Wasp HeadFormation in the southern Sydney Basin, eastern Australia). The preliminary quantitative analysis indicates a highcompositional similarity in both regions but occupancy exhibits important differences: brachiopod-dominated faunascan be found in eastern Australia (Tomiopsis and Trigonotreta are the most frequent taxa), and bivalve-dominated faunasare characteristic in eastern Argentina, where the brachiopods are poorly represented with the genera Tivertonia andTomiopsis. In this locality, the development of r-strategy taxa, such as the bivalve Eurydesma, during the end of a glacialepisode would adversely affect brachiopods? abundance. This is also consistent with previous studies that indicatethat brachiopods already showed a decrease in importance in Pennsylvanian communities from Argentina. Relativeabundances of brachiopods and bivalves in both localities may reflect differences in the regional environmental conditionsbut, unfortunately, eastern Argentina lacks younger records to compare the faunal turnover with that of theAustralian sequences. Despite the ecological structural differences identified (i.e. brachiopod:bivalve ratio), the postglacialEurydesma fauna flourished in western and eastern Gondwana and it is striking that two faunas located on theopposite margins of this paleocontinent show such high compositional similarity during the development of a globalpostglacial event. This is particularly significant considering that the type of the basins (i.e. restricted vs open basins),biological features, paleoenvironmental conditions directly related to glacial dynamics, and also the diachronism of thetransgression, can be controlling the composition of this fauna.