This
is a rarely seen member of the Ophiuroidea, or Brittlestars, a large
example of Geocoma libanotica. The generic name is derived from
the location (Lebanon), an area better known for its fine preserved
fish and Crustaceans. The sublithographic limestone also preserved
incredible detail here as well. The genus is also known from the
Jurassic deposits of Solnhofen, Germany where
Geocoma carinata is often seen. These Brittlestars are over 50 million
years younger, showing that the genus was quite long-lived. Brittlestars
are able to regenerate lost arms. The most spectacular feature of
the larger example which is seen in ventral mode is the 3-D preservation
of the arms. Unlike most which are relatively featureless, this
one has great detail; if you run your finger over the arms, the
ambulacral detail is strikingly evident.
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