Dec 18, 2008

Spiders of the Sea

How can crabs be the spiders of the sea, when there are actually sea spiders? I'm not talking about spider crabs, or even crab spiders. I mean actual arachnids roaming the oceanic depths.

Researchers exploring the Ross Sea of Antarctica dredged up this Giant Sea Spider. That's right, I said Giant Sea Spider. This particular specimen is about 10" in diameter (25 cm), and they can reach upwards of a foot on the larger specimens.

UPDATE: Christopher Taylor tells me that these aren't actual arachnids. National Geographic says that they are, but I'm inclined to defer to Christopher on this, given his expertise. He would also like us to know about the proboscis they use to ram into hapless cnidarian prey to suck out their innards. Lovely.




















Marine arachnids are found in all oceans, but are the largest and most populous in Antarctica. This is another example of deep-sea gigantism. The theory is that the cold water, few predators, and high oxygen levels allow for super-sized organisms. Maybe this is why Santa Claus chose one of the poles for his abode.

(never thought I'd tie in Santa with a sea spider post)

Thanks for the article, Nervy.

8 comments:

Danielle said...

You have now made it dangerous to go anywhere without having spider encounters...

WHY MUST YOU DO THIS TO ME?!

What if I wanted to live in blissful ignorance?!

Also, your blog is so awesome.

Raging Wombat said...

I'm sorry, and thank you. :)

Christopher Taylor said...

Sea spiders aren't arachnids, they're a different group of arthropods all of their own. Very, very odd animals.

You forgot to mention that the large tubular proboscis (at the left end of the animal in the photo) is thrust into its hapless cnidarian prey and used to suck out its internal juices.

Ivan Privaci said...

He's right - Sea Spiders are "Pycnogonids", not "Arachnids". The two Classes are related, though (along with "Merostomatids" i.e. Horseshoe crabs, interestingly enough).

They're all classified under the subphylum of "Chelicerata".

(Not sure why I know this - I usually stick to normal organisms and yeasts rather than freakish soft-celled multicellular eukaryotes).

morgan said...

You guys totally forgot to mention the fact that they have their eyes mounted on a little turret at the top of their body... so awesome!

http://www.awi.de/fileadmin/user_upload/News/Selected_Topics/Biodiversity/Life_below_Ice_Shelves/Photos_for_Download/Unknown_species/Pycno_eggs--PL_01.jpg

Nervavels said...

turreted eyes, invasive proboscis, and I like knowing about the arthropod classification. What is cnidarian? I'm fascinated. Not sure I'd want one of these as a pet though...

Sabina E. said...

god, that is one scary looking spider thingy. i would cry if i saw it while swimming in the ocean!

0s0-Pa said...

As long as they aren't toxic I won't mind them too much.
-Rich @ Most Feared Animals