A global review of the Late Mississippian (Carboniferous) Gigantoproductus (Brachiopoda) faunas and their paleogeographical, paleoecological, and paleoclimatic implications

Abstract

The gigantic Gigantoproductus-bearing brachiopod fauna is one of the most distinct marine benthic faunas in the Late Mississippian (Early Carboniferous) in terms of its huge size, extremely thick shell, and delicate costation. A global review of 145 different occurrences throughout the world reveals a total of 57 Gigantoproductus species recorded. Our investigation into their spatial and temporal distributions indicates that Gigantoproductus was originated from the Moscow Basin in the middle Visean, and then in the late Visean migrated southwestward to western Europe and North Africa and eastward to North China, South China, and Japan. The genus reaches its acme stage in species diversity and abundance in the late Visean, then gradually declined in the early Serpukhovian, and finally disappeared in the late Serpukhovian. Gigantoproductus and its related genera were distributed mainly in the circum Paleotethys region in the tropical and subtropical zones, and favored a relatively shallow shelf environment with high energy and warm water condition with little thermal tolerance. The absence of the Gigantoproductus and its related genera in America suggests the east–west Rheic seaway was closed before the Gigantoproductus fauna appeared in the middle Visean. The waxes and wanes of the Gigantoproductus faunas temporally coincided with the paleoclimatic shift from greenhouse to icehouse stage in the late Visean and early Serpukhovian. And the final extinction of these gigantic brachiopods in the late Serpukhovian implies tropical cooling towards the late Serpukhovian by the expansion of the LPIA glaciers.