This reddish trilobite of the species Elrathia kingi shows  a rare pathology on the right free cheek is well noticeable.  There are two nodes with about 2-3 mm in size.  These could be injuries at a late stage of healing.  Such nodes or pustules are also interpreted as potential parasitism on Trilobites.   Injuries, especially predation marks are actually not that rare at Elrathia kingi. This type of pathology, on the other hand, is very unusual Elrathia kingi.  
The trilobite also offers a beautiful reddish preservation and presents itself in the middle of the decorative matrix.  The Elrathia itself is about 28 mm long.

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