Name: Ophiurina lymani
Phylum Echinodermata, Class Ophiuroidea, Order Ophiurida
Geologic Time: Lower Devonian Seigenian/Emsian Stage
Size (25.4 mm = 1 inch): 37 mm armspan
Fossil Site: Hunsruck Slate, Bundenbach Germany
 This
is a particularly well preserved specimen of an Ophuroid (brittlestar)
fossil known as Ophiurina lymani. The Hunsruck slate is famous for
its fossils, many of which have pyritization present. Rapid burial
and pyritization was what led to the many wonderful examples of early
Devonian life from the region. The chemistry of the silt was such
that low organic content and high levels of iron and sulfur allowed
the pyrite to diffuse into the tissues rather than be deposited in
the sediment. The mudstones were metamorphosed into slate during the
Carboniferous. The slate was quarried for roofing tiles, and the quarrymen
would save the fossils for later sale. Now that the quarries are no
longer open, future supplies of these wonderfully preserved benthic
organisms will only come from existing collections. This is an exceptional
example from this famous Lagerstatt fossil site. |
