Hi Erin, welcome to the forum.
You might not get many posts to this question, as it was very reciently covered in extreme depth (winks at Hanibal <img src="wink.gif" width=15 height=15 align=middle> ), it is not that people on this forum are unsocialble, it is just they are a little battle weary <img src="smile.gif" width=15 height=15 align=middle>
To answer your question, Hanibal is right, even though the book just described it as a Harpy (normally only serrated), the film makers seemed to have got hold of a quite rare (until this coming year), plain edged Harpy.
Stick around and you will learn an awful lot about knives, and Spydercos in particular.
"Walk softly, but carry a big stick."