The Early Ordovician gastropod Ceratopea from East Greenland

Abstract

Opercula of two species of Ceratopea are described from an outcrop of the Narwhale Sound Formation on Ella Ø. This is the second known occurrence of the genus in Greenland, but is the first illustration of specimens. One of the species herein named C. billingsi has been illustrated at least twice from other areas; it may be useful for intercontinental correlation. The second species is not formally named as all specimens are incomplete. The two species indicate the age of at least part of the Narwhale Sound Formation as late in the Early Ordovician.