Here is a large and pathological "Utah Trilobite" of the species Modocia typicalis from the Marjum - Formation. This trilobite shows on the left librigena a very nice pathology in a fairly early stage of regenaration. The left genal spine is only rudimentary regenerated as a small inward curved micro spine. Also the anterior border and the burrow furrow of the left librigena are dis formed.
Usualy this kind of injures are been interpreted as predatory bite marks from trilobite hunters such as Anomalocaris. But also a injury during the molting would be plausible on pathological trilobites like this. However this piece demonstrates nicely the remarkable regeneration and efficient wound closure capability’s of Trilobites as it is illustrated on many symposia by Michael Zwanzig (Berlin).
The trilobite itself offers beside of the pathology a respectable size and a detailed preservation.

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