| Cyrtometopus
      clavifronsTrilobites
      Order Phacopida, Suborder Cheirurina, Superfamily Cheiruroidea,
      Family Cheiruridae Geologic
             Time: Lower Ordovician, Kunda Horizon Size: 35
          mm  Fossil
            Site: Wolchow River Region, Kunda Horizon, St.
        Petersburg region, Wolchow river, Russia 
 
         
          |  Description:
                Coming from the nearly half billion year old Middle Ordovician
                Kunda
              Level deposits of the Wolchow River region near Saint Petersburg,
                Russia, this is an example of a member of the Order Phacopida,
                Family
              Cheiruridae of the genus Cyrtometopus. Its affinities with other
                 Cheirurids such as Nieszkowskia
                are apparent, but there are substantial differences as well.
                The
              trilobite itself is 35 mm long (measured along the curve) and 25
                mm wide at the dramatically backswept pygidial spines. 
                Notice  the small Brachiopod to the left of the right genal
              spine. Also 
              see: Russian
              trilobites.
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