(Node spiders with human heads... or, uhm, something.)
Yet another one of those monsters that have changed more than a little bit over the history of Dungeons & Dragons.
In Classic D&D, monsters called "aranea" appear in module X1 The Isle of Dread that came with the D&D Expert Rules. Araneas are a race of giant spiders. They're about the size of a small horse, and are easily distinguished by the big lump on the back and their almost hand-like claw extensions in their legs. This lump holds their brains. As you might expect from the size of the brains, araneas are very intelligent and are competent spellcasters. Araneas live in middle of the uncharted jungles of the Isle of Dread in their spider-web homes. ("All home-woven!", they say...)
X1 is undoubtedly one huge module that had some impact later on, so quite oddly, Dungeons & Dragons 3rd Edition also includes them! (Which is somewhat interesting, with precursory googling I couldn't find a reference that they would have appeared in AD&D 1st/2nd ed. Monstrous Manuals... please correct me if I'm wrong.) As in the case of kobolds, they're quite recognizable even when they're not the same. The (so far non-OGL-licensed part of) System Reference Document describes aranea as a shapechanger that appears naturally as a large spider, and change into a humanoid or a spider-humanoid hybrid form. Regrettably, this form isn't described that well in the SRD so I can't say whether the form is similar to the X1 araneas, but other stats seem familiar (three hit dice and tons of web, indeed!) It may have been just a caffeine hallucination or a bad nightmare after that, but it also seemed to me that these creatures were also included in Neverwinter Nights toolset.
(I've also heard some rumors that the kopru - another monster race from The Isle of Dread - would have got reincarnated in 3rd edition at some point, but it's not in the SRD. But then again, the SRD doesn't cover everything...)
Sources:
- David Cook ja Tom Moldway. X1 Vaarojen saari, Dungeons & Dragons Fantasiaroolipeli Expert-seikkailumoduli. Protocol Productions ja TSR, inc., 1988.
- Wizards of the Coast and Open Gaming Foundation. "Monsters (A)". System Reference Document, 25/11/2001. Online <URL:http://www.opengamingfoundation.org/srd/srdmonstersa.html>. Accessed 2003-01-07. Author information missing.