The highly fossiliferous succession of Smithian (Early Triassic) ammonoids from northwestern Guangxi (South China) provides a key equatorial record, at the boundary between Tethys and Panthalassa. After the end-Permian extinction, ammonoids reached their first major diversity peak during Smithian times, coupled with a marked contrast in their latitudinal distribution. This monograph contains a part of the fundamental taxonomic and biostratigraphic data of a more comprehensive research project addressing patterns of recovery in time and space of Early Triassic ammonoids and other marine clades, in conjunction with global paleoceanographic and paleoclimatic changes.
Arnaud Brayard is currently assistant lecturer in Paleontology in the Laboratoire des Mecanismes et Transferts en Geologie, Toulouse, France. His main research topic is the paleobiogeography and diversity of Early Triassic ammonoids, with emphasis on interactions between climatic changes and large-scale biodiversity patterns in time and space. Hugo Bucher is professor of Paleontology with the University of Zurich and with the Earth Science Department of the Swiss Federal Institute of Technology Zurich. Patterns of biotic recovery following mass extinctions are among his main research topics, with emphasis on the Early Triassic and ammonoids. Other related research topics of his include quantitative biochronology and biogeography, as well as the morphogenesis of the mollusk shell and its phylogenetic implications.