Friday, April 22, 2011

Friday Field Notes-- Distracted by Spiders...

Nephila jurassica...  (found in the Daohugou beds in northeastern China)



...And this is exactly why I can't get *anything* done.  That up there is the biggest spider fossil ever found (thanks, Alice!!).  Not just any old spider, either.  I took one look at the name and said, "Ooh! Ooh! Ooh! Nephila!!"


That's right-- that amazing, 165-million-year-old Mid-Jurassic fossil is in the same genus as my beloved Jorougumo (Nephila clavata).  This one, remember?

Nephila clavata (Jorougumo...the Binding Lady)  Compare the legs!  The Betty Grable of spiders...;-))


And with this fossil, genus Nephila is now 130 million years older than previously suspected (the oldest known fossil prior having been a mere 34 million years old).  But just look at those legs!  There's no doubt that the Jurrasic had orb-web spiders.  It's spiders that spin huge, sticky webs that sport those beautiful, curving, fine-tipped legs that can dance across an intricate web evolved to trap insects without getting stuck themselves.  According to the Smithsonian article, those fossil legs stretched 6 inches! (Go read the article--they think it may even have been able to catch and eat small bird-like dinosaurs!)

Carefully...carefully...or she will eat you...;-))


Unlike modern members of the Nephila genus, however, some researchers think the Jurassic species was not sexually dimorphic--that the male was possibly roughly the same size as the female.  A 130-mya male spider fossil of the Cretaraneus genus found in Spain was the same size as the female, leading researchers to postulate that Nephila at that time may also not have been dimorphic.

Wheee! I am so addicted to spiders:-))

Araneus diadematus... Niwaonigumo (European Garden Spider)
Click to enlarge...you know you want to;-)

The other day I was walking home from school and saw this *darling* little spider, who was so itty-wee my camera wouldn't focus on her.  Had to put my hand behind her so she'd be in focus instead of the background foliage.  But I don't know who she is!  Spider Experts of teh Interwebs-- HELP!  Who is this spider?  Found
April 17 in Yokohama, Japan in a bush next to the street at eye level... should I put her on milk cartons?

Update:  I do now-- should have done more homework before posting.  But I thought I'd be days searching for "small brown spider" on Google image search...   So, after smacking my head into the table when I realized that she was sitting on an orb-web...well, duh.  I could have put "small brown orb-web spider" into Google and gotten there much sooner.  So she's "just" a garden spider--also called the Diadem Spider or Cross Spider because of the markings on her back (interesting side note:  "The white dots result from cells that are filled with guanine, which is a byproduct of protein metabolism.").  In Japanese, she's "Niwaonigumo"--the Garden Ogre Spider.

Here's where things get interesting, though.  Turns out, Nephila clavata above, Araneus diadematus here, and Argiope bruennichi below used to all be classified in the same genus-- Epeira, a sort of catch-all taxa for a wide range of spiders in the 19th century.  Curvy legs and round web?  Into Epeira you go!  Until, that is, somebody noticed that Epeira was getting *awfully* full, and started splitting.  The Golden Orb Web spiders (Jorougumo above, and also apparently the new Chinese fossil as well) were given an entirely distinct family to themselves (the Nephilidae) and four separate genera (Clitaetra, Herennia, Nephila, and Nephilengys).  More than enough space for everyone to get his own bedroom.  Epeira was dumped in favor of Araneidae (the former now being considered a junior synonym of the latter), into which family both the above Araneus genus (my pretty Diadem Spider) and the Argiope genus below (the gorgeous silver-faced Wasp Spider) were placed.

There!  A nice, neat family, dusted and cleared of clutter.  Sort of.  Looking up Araneidae to see which genera were put there, I find... 30 genera starting with the letter "A".  170 genera all together in the Araneidae family.  I'd say there's a bit more spring cleaning to be done..;-)
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Oxytate striatipes... Wakabagumo

I also found (and nearly stepped on--gomen!) this lovely one whose name in Japanese is "Wakabagumo".  A name which means, appropriately, "Young Leaf Spider"--and he's exactly the color of a glowing new leaf.  Yes, that's right, He in this case.  This species is sexually dimorphic (the male being about 8-10mm, the female 12-13mm), but not so much as Jorougumo.  The male is more easily  distinguished by his narrower abdomen than by his size.  Not an orb Web spider, though-- this one is a Green Crab Spider (family Thomisidae), so called because of the way they hold their front legs and the fact that they can scuttle in a manner similar to crustaceans.

Tiny new Ginkgo leaves illuminated by the morning sun...



See?  Same color...










"Hey! Giant person! Look out!"


 ...the only reason, in fact, delicate little Wakabagumo was saved from being squashed was a young grasshopper who jumped in front of me.  I stopped to look at him, then thought I saw another.  But, no!  Almost the same size and color, but a new (to me) spider!  Squee!

 And I almost stepped on him!  I tried to tiptoe after that, big hulking giant that I am...


*********
...and in other spider news...

Nagakoganegumo... Argiope bruennichi (Family: Araneidae)
...striking silver-faced Argiope, the Wasp Spider (a writing spider), whom I posted about last fall, I'm hoping to see again soon.  At the end of that post, I put up a photo of her egg sac, which was precariously pasted into a chain-link fence.  I kept an eye on it all winter.  And in January...

they made it!
Now I have to think of baby spider names...












Mata asobou, ne!

p.s.-- I promise I will post the rest about Tsukushi.  That's a whole 'nother rabbit hole, though... nodes and spores and strobili and...

9 comments:

  1. Isn't it cool! It was found in northeastern China (the link is in the caption under the fossil photo). I didn't post the other photo in the Wired Science article that Alice links to-- it's a close-up of one of the legs, and you can see the hairs on it!

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  2. I got a bit interested after clicking Alice's. Here's a couple more links for you:

    The oldest spider web found in amber

    And

    Spiders In Space. (I had to capitalise it, cos I keep saying it like the Muppets, Piiiiigs Iiiiiiin Spaaaaaace. Ahem.)

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  3. Daz--oooh! Thanks for clicky links! (And... as soon as my eyes focused on "Spiders In Space", my brain went "Spiiiiders Iiiiiin Spaaaaace"... we obviously watched the same Muppetts' episodes:-))

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  4. Nothin' like a bit of high culture, I say. And that was quite possibly nothin' like… :-)

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  5. i TOTALLY thought of you earlier this week when i saw that spider fossil - i was going to email you, but i got distracted by novely stuff and forgot. Glad someone else was on the ball
    And yay for the baby spiders!!

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  6. Daz--high culture indeed;-))

    Sarah-- you thought of me? Thanks! Wow--*everybody* is totally more on the ball than I am! No fewer than three people saw that spider article and told me about it... *sigh* permanently out of it, I suppose. No worries about distractions--as you can see, it happens to me all the time! Novely stuff is really important--go get that novel queried, girl! We want to *read* it!

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  7. I totally thought I'd commented on this but it's not there! I hate that.

    Anyways, once again, all this is so fascinating and I love the gorgeous Jorougumo still.

    I always think of you whenever I am out and see a spider. "D'Oh! I should have brought the camera to take a pictures for Amy!"

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  8. Yeah--I hate when that happens, too... isn't she a gorgeous one? Thanks for posting that! And thanks for thinking of me when you see spiders:-))

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