A recently discovered clypeasteroid, Echinodiscus colchesterensis species novum, from the Alexandria Formation (Late Tertiary), South Africa
Smuts, Willem J
BERNARD PRICE INSTITUTE FOR PALAEONTOLOGICAL RESEARCH
A recently discovered astriclypeid, Echinodiscus colchesterensis sp. nov. from the Late Tertiary of South Africa is described and classified as ancestral to the living E. bisperforatus on the basis of certain morphological characteristics and parameters. These include a smaller interlunule angle, different ambitus shape, breadth/ length ratio, and similar growth trends.
astriclypeid , interlunule angle