Atlantic Horseshoe Crab Limulus polyphemus

Horseshoe Crab
Horseshoe Crab
Horseshoe Crab
The Horseshoe Crab was originally called the Horsefoot crab being thought to resemble a horse's hoof. It is a "living fossil" since similar forms are said to have lived over 230 million years ago.
Horseshoe Crab
Horseshoe Crab
Horseshoe Crab
They are not true crabs, nor even crustaceans, but are closely related to arachnids (spiders, scorpions). They have 9 eyes and blood which turns blue when exposed to air.
Horseshoe Crab
Horseshoe Crab
Horseshoe Crab
There are 4 living species, similar-looking but in 3 genera. That shown is the Atlantic Horseshoe Crab, native to the eastern coast of North America. The other 3 are native to Asia.
Horseshoe Crab
Horseshoe Crab
Horseshoe Crab
They can regrow lost limbs. They burrow in the sand for prey, walk on the seabed but swim usually upsidedown. Larger females can grow to 60cm long including tail. They are vulnerable due to over-harvesting and habitat loss. Their blue blood is used in medical science across the globe to rid vaccines of bacteria, including Covid-19 vaccines, increasing the pressure on them.