Cambrian bivalved arthropods

Abstract

This monograph is part of a series of publications by the two authors and their collaborators (Williams et al. 1994; Hou et al. 1996; Melnikova et al. 1997; Williams & Siveter, in press) aiming toward a comprehensive inventory of an important component of the Palaeozoic arthropod fauna: the bradoriids and the phosphatocopids. These two groups of small bivalved arthropods occur worldwide from the early Cambrian to the early Ordovician. From the time of their discovery in the late 19th century, these fossils were referred to the ostracod crustaceans until their soft parts were discovered in the Upper Cambrian of Sweden (phosphatocopids of the orsten faunal assemblage; Muller 1979, 1982), the Middle Cambrian of Australia (Walossek et al. 1993), the Lower Cambrian of Great Britain (a phosphatocopid baby, Hinz 1983), and the early Cambrian of China (Chengjiang fauna; Hou et al. 1996 for the braSeilacher, A. 1992: Vendobionta and Psammocorallia: lost constructions of Precambrian evolution. Journal of the Geological Society, London 149,607413. Seilacher, A. 1994: Early multicellular life: Late Proterozoic fossils and the Cambrian explosion. In Bengtson, S. (ed.): Early Life On Earth Nobel Symposium No. 84, 389400. Columbia University Press, New York, N.Y. Valentine, J.W. 1992: Dickinsonia as a polypoid organism. Paleobiology