Asaphus cornutus Russian trilobite

This fossil exemplifies the expression of the trilobite genome at its finest. A huge and magnificent Asaphus cornutus from the Ordovician strata near Saint Pertersburg, Russia. This specimen is at or near the species size limit and has extraordinary exoskeleton preservation. The Asaphus is in assciation with a 38 mm-diameter cystoid. This taxon derives its species name cornutus from the Latin for horned, referring to the eyestalks. Asaphus cornutus is midway or so in an evolutionary adaptation sequence of increasing eye stalk heights among Russian Ordovian trilobites on the Asaphidae family.

Also see: Russian Trilobites Gallery Russian Asaphidae Evolution Sequence