Contributed by Bruno Pereira, December 2011
Diagnostic Features |
|
---|---|
Distribution | Eocene, Armenia |
Type | P. armenica Poretskaya, 1968, p. 290, by original diagnosis |
Species Included |
|
Classification and/or Status | Echinacea; unnamed family (triplacidiids) Monotypic |
Remarks | Originally placed in the Phymosomatidae but ambulacral plating argues against this. Close to Triplacidia, differing in having a rather irregular distribution of ambulacral tubercles to its compound plates. Poretskaya, E. S. 1968. Polyplacidia artenica - a new genus and species of sea urchin from south-western Armenia. Ezhegodnik Vsesouznoe Paleontologicheskoe Obschchestvo 18, 286-297, figures 1-6, plates 1-2. [in Russian] |