David Woodfall / Lesser horseshoe bats (Rhinolophus hipposideros) in magnesium mine, Shropshire, England, UK, April.

Piotr Naskrecki / Decken's Horseshoe Bat (Rhinolophus deckenii) drinking, Gorongosa National Park, Mozambique

Dietmar Nill / Slow motion clip of a Greater horseshoe bat (Rhinolophus ferrumequinum) catching a moth in flight, Germany, captive.

Ingo Arndt / Rear view of Horseshoe crab (Limulus polyphemus) with trail in sand, Delaware Bay, Delaware, USA, May

Ingo Arndt / Aerial view of the "American Falls / Horseshoe Falls", Niagara Falls, North America

Ingo Arndt / Aerial view of "American Falls / Horseshoe Falls", Niagara Falls, North America

Alex Hyde / Lesser horseshoe bat (Rhinolophus hipposideros) roosting in cave. Croatia. November.

Alex Hyde / Greater horseshoe bat (Rhinolophus ferrumequinum) roosting in cave. Croatia. November.

Doug Wechsler / Horseshoe crab (Limulus polyphemus) embryos, Delaware Bay, New Jersey, USA, June.

Juan Carlos Munoz / Horseshoe Bend in the Colorado river, near Page, Arizona, USA, February 2015.

Sean Crane / Horseshoe Crab (Limulus polyphemus) group spawning at high tide at sunset, Cape May, New Jersey

Sean Crane / Horseshoe Crab (Limulus polyphemus) group spawning at high tide at sunset, Cape May, New Jersey