Charybdis is a genus of swimming crabs from the Portunidae family that is still present today. In this case, it is a very young fossil being only around 10,000 years old. It comes from the Holocene deposits of a coastal outcrop near the city of Shizuoka in Japan. The crabs from this site are preserved in more or less heavily cemented geodes, almost all of which have a weathered and soft outer layer. Underneath, the rock can be extremely hard and concrete-like, which does not allow any separation from the fossil. An adequate preparation is then only possible with a sandblasting unit.

This specimen was covered with only a few millimeters of stone on both sides, making it comparatively easy to work with. Legs and carapax could be exposed on both sides and the pincers were fully exposed. The shell has an excellent preservation of detail.
Fossil: Charybdis japonica, female specimen

Locality: Shizuoka (Japan)

Formation: Holocene

Total Width: 11cm (4.3 inch)

Collection: Takashi Ito

Work required: 5 hours