Black Widow (Latrodectus hesperus)

Shelob's Lair

Across the width and height of the tunnel a vast web was spun, 

orderly as the web of some huge spider, but denser-woven and far greater, 

and each thread was thick as rope.

    Sam laughed grimly. 'Cobwebs!' he said. 'Is that all? Cobwebs! 

But what a spider! have at 'em! Down with 'em!'

    In a fury he hewed at them with his sword, but the thread that he struck did not break.

It gave a little and then sprang back like a plucked bowstring,

turning the blade and tossing up both sword and arm.

--The Two Towers by J.R. Tolkien