The Saudi Royal Commission for AlUla has announced the discovery of exceptionally rare horseshoe crab fossils in Saudi Arabia, dating back approximately 465 million years. This significant find offers new insights into ancient marine life and geological events.

• These fossils are among the oldest known horseshoe crab fossils worldwide, dating to the Ordovician period (approximately 485-444 million years ago).
• The discovery was made in the AlGharameel Nature Reserve in AlUla, northwest Saudi Arabia, and was published in the peer-reviewed journal Gondwana Research.
• A notable detail is that all fossils were preserved upside down, a previously unrecorded mode of preservation, with trace fossils indicating attempts to self-right.