Yochelcionellids from the Early and Late Cambrian of North Greenland

Abstract

Yochelcionellids are small, slightly coiled, cap-shaped problematic molluscs characterised by a prominent tube, the snorkel, which emerges from the shell wall below the apex. They were originally described from the Middle Cambrian of Australia (Runnegar & Pojeta, 1974; Runnegar & Jell, 1976, 1980) and were assigned to the Class Monoplacophora, together with the often similarly coiled, but snorkel-lacking, helcionellids. Yochelcionella has subsequently been described from the Early Cambrian of Pennsylvania, U.S.A., by Runnegar & Pojeta (1980).