Living Fossil: Horseshoe Crab Larvae Now on Exhibit at Shikoku Aquarium

Shikoku Aquarium (located in Utazu, Kagawa) is now exhibiting horseshoe crab larvae, frequently referred to as "living fossils."

The larvae on display were originally bred and hatched at the Kasaoka City Horseshoe Crab Museum in Okayama Prefecture. These individuals were being raised for wild release before being transferred to Shikoku Aquarium for this educational exhibit.

Horseshoe crabs were once found throughout the Seto Inland Sea. However, due to factors such as land reclamation and marine pollution, they have vanished from most areas except for a few specific regions. Kasaoka City in Okayama Prefecture is designated as a national natural monument and is a known breeding ground. In Kagawa Prefecture, they are only rarely caught in bottom trawls, and their population is believed to be significantly diminished.

This exhibition recreates the natural habitat of horseshoe crabs, allowing visitors to observe the larvae as they burrow into the mud and feed on plankton.

We hope that by bringing visitors closer to these horseshoe crabs—creatures that have remained virtually unchanged for millions of years—we can encourage everyone to think about what can be done to ensure their survival into the future.

[Exhibition Details] Period: Starting Saturday, May 16, 2026 Location: 1st Floor, Main Building, Setouchi Zone (next to the "Living Fossil" space) Species: Horseshoe crab (2nd instar larvae) *Note: Exhibit content is subject to change or termination without notice based on the condition of the animals.