I think they swim upside down.

Oh, My Fucking Celestia! O.O

I picked one of these guys up at an aquarium once, they’re cool as fuck.

._. Excuse me, I feel sick.

I actually think these guys were really cool…till i saw this now their on the nope list.

For some reason, seeing that crab makes me feel sick..

Fun fact: Horseshoe crabs do not have jaws, the crush their food with their legs.

@Gundlach  
i thought more green  
used to stop bleeding

ohh trilobites

Kabuto you’re still the second best fossil mon. Areodactyl is always 1st.

@Background Pony  
Not exactly gills, but similar. They’re called book lungs, and they pump the crab’s blood with each flapping motion, as well as moving themselves through the water to pick up oxygen. Scorpions also have book lungs. It’s one of the reasons they’re so hard to fumigate. Unlike insects who have breathing holes all over their bodies providing a path for the poison to go deep inside, scorpions and horseshoe crabs have a membrane barrier between their blood and the air.
 
When I was a little cub, I used to go out on the beach during hatching time, and help their little larvae make it from the nests to the water. Horseshoe crabs are 100% beneficial and harmless.

@ninjasquirle  
and to make sure that batches of medicine or medical equipment aren’t infected before they are sent out/used

I’m with Fluttershy here, horseshoe crabs are cool. Also adorable.

Not only is their blood blue, but its one of the most powerful natural disinfectants evar

@Darth Biomech  
I’m not super good with horseshoe crab biology, but I think those are its gills.

These things are a delicacy in Southern China.

Horseshoecrab: “Fluttershy, Will you help me get up or whatever?”

Fun Fact: Horseshoe crabs, despite their name, are actually more related to spiders than to their crustacean counterpart.

@Poptard  
Agreed.
 
@ninjasquirle  
Awesome.

It is cute, I think. Also didn’t knew that they also have flaps for swimming. 0_o

They cometh.  

 
Nice doggy

I actually really like these guys because they are interesting biologically as they are over 450 million years old and ironically are much more related to arachnids than crustaceans. Also their blood while blue is used by medical companies to detect bacterial infections in people.

Oh my god, it’s like a facehugger. I know what my nightmares will be filled with tonight.