Tuesday, June 26, 2012

X/ABC Wednesday


X is for Xiphosuran 

Xiphosuran is an anthropod of the order Xiphosura which includes horseshoe crab and other extinct forms.  I found this strange-looking creature at the shores of Snake Island in Palawan---it was the first time that I have seen a horseshoe crab (Carcinoscorpius rotundicaudia), I didn't think it was a living creature.  I noticed the metallic look of its shell, thought it was a helmet of some kind.  When it moved, I thought it was sea turtle but when I looked closely, the shell resembles that of a crab.  Nobody can tell me at the time what this was called.  When I came home, I showed this image to my brother and he said it's a mangrove horseshoe crab.

Despite its name, horseshoe crabs are more closely related to spiders and scorpions than to crabs.  They live primarily in and around shallow ocean waters and occasionally come  on shore for mating.  Horseshoe crabs have no hemoglobin in their blood, they have hemocyanin to carry oxygen.  Because of the copper present in hemocyanin, their blood is blue.  Their blue blood is widely used in biomedical sciences for the development of drugs for diseases like mental exhaustion and gastroenteritis.

Considered by biologists as living fossils because they have remained practically unchanged in terms of shape and size for millions of years.  Fossils of horseshoe crab have been dated to roughly 450 million years ago.


Linking to ABC Wednesday

12 comments:

Mar said...

How interesting!! fun looking creature :)

X is for Xarel.lo

Roy Schulze said...

If they only come on shore for mating, shouldn't this photo be rated X? My unseasonal entry this week is Ex Mess.

Roger Owen Green said...

Hmm - thought maybe a hermit crab stole a shell!
ROG, ABC Wednesday team

Photo Cache said...

so much new knowledge in this one post. thank you.

that thing :) looks very familiar to me, idk why.

Meoww said...

I have seen these crabs in a comic book, long back (!) and that they were used in medical research. Blood is blue- Interesting.

Leslie: said...

Wow! I guess you can't eat them, huh?

Leslie
abcw team

Carver said...

Great choice for X day. Carver, ABC-Wed. Team

Jama said...

I remembered a late uncle who used to bring the horseshoe crab from his fishing trip and the aunt would cook it for us. Not much flesh but the eggs are divine! There's a few restaurant in Malaysia that sell this dish.

eJoops said...

Wow, that's a cool looking crab!

X is for Xeroderma

chubskulit said...

I'm not sure if I have seen one of those or not. I grew up in a coastal area but I don't think, I have seen one..

Xanthopsia
Rose, ABC Wednesday Team

magiceye said...

that was new and interesting. thank you

Annie said...

Nice photo of that cool sea creature!