Here is a inexpensive example of a trilobite of the species Ogygiocarella debuchii  with some very nice details. 
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Location:  | Minsterly, Shropshire, UK | ||
| Size of Trilobite: | about 79 mm long | ||
| Age: | Ordovician, Llanvirn Didymograptus artus-Biozone Hope Shale Formation (about 455 Mill. Years) | ||