CLASS PSAMMOCORALLIA (COELENTERATA, VENDIAN ORDOVICIAN) - RECOGNITION, SYSTEMATICS, AND DISTRIBUTION

Evidence from the Lower Cambrian of Sweden and Mongolia and the Ordovi cian of Jordan shows the body fossil nature of Protolyellia and Spatan gopsis. This interpretation is tentatively extended to the Vendian Bel tanelliformis/Nemiana. Systematically the Class Psammocorallia compris es Protolyellia princeps Torell, P. benderi (Huckriede), P. simplex (P alij), and Spatangopsis costata Torell, S. alata n.sp., S. mongolica n .sp., and S. scotica n.sp. Brooksella cambria is interpreted as a trac e fossil reminiscent of Asterosoma. Similarly shaped sand volcanoes (' Astropolithon') owe their medusoid morphology to interference with bio mats.