Horseshoe Crab Anatomy. This video shows both a live male and female horseshoe crabs. I show you how to tell what sex the horseshoe crabs are and point out different parts of their anatomy, such as 10 eyes. These horseshoe crabs were captured at Mosquito Lagoon in Titusville, Florida just a few mile from the Kennedy Space Center. To learn more about horseshoe crabs go to