| Dysplanus
          acutigeniaTrilobite
      Order Corynexochida, Superfamily Illaenoidea, Family  Illaenidae Geological
      Time: Lower Ordovician, Asery Horizon Size: 45
        mm Fossil
      Site: Wolchow River Region, St Petersburg, Russia 
 
         
          |  Description: 
              Coming from the Middle Ordovician Asery Level deposits of the Wolchow 
              River region near Saint Petersburg, Russia, this is an example of 
              a rare trilobite of the genus Dysplanus. It is obviously related 
              to Illaenus, having a similar high profile of the cephalon, presumably 
              a feature that allowed it to plow the substrate looking for a meal. 
              One of the most obvious differences is that Dysplanus has NINE thoracic 
              segments rather than the TEN of Illaenus. Its dark caramel-colored 
              Calcite shell is well set off by the white limestone matrix, with 
              the trilobite preserved well centered. This is a taxon is only very 
              rarely seen. As always, the skillful Russian preparators have shown 
              this fine 3-D specimen to best advantage.
 Also
                see: Russian
            Trilobites Gallery |  |