Help me identify this small colorful spider found in Amazon Basin of Bolivia

[Hanumann]

I was walking on one of the hiking trails in Madidi National Park in Bolivia's Amazon Basin with my tour guide when I spotted a small, very exotic looking spider nested in its web amidst the dense foliage.

The little gal (she) was no bigger than ¼ inch (6mm) long, but had an unusual oblong shaped body with yellow markings on her flanks and rump. I maneuvered my camera within 2 inches of the creature and snapped a couple of pictures.

I know that this particular spider is by no means rare nor is it one of the more abundant spider species in the Amazon rainforest. Admittedly I am not a spider expert nor do I consider myself that knowledgeable about spiders. That being said, are there any arachnophiles out there who can identify this little beauty?:wall:

 

[Widowman10]

possibly a micrathena species.

edit: looks just like this one here (no ID given here though)

 

[davisfam]

We would def. have to agree with ‘Widowman10’ on this spider being from the genus Micrathena. After doing a little more research on this genus in the Bolivia area, we think it’s a possibility of two different species, if not more.

Our first possible ID is the M. sagittata (Arrow shaped Micrathena) although the center of the dorsum is not yellow as usually seen with M. sagittata nor are the tubercles red at the base. Here is a link to the M. sagittata:
http://bugguide.net/node/view/2020

Our second possible ID is the M. pichincha although this species is not an exact match either. Here is a link to the M. Pichincha:
http://upload.wikimedia.org/wikipedia/commons/6/67/Micrathena.pichincha.-.tanikawa.jpg

-This genus is known to be variable; the red highlights are not always present in the M. sagittata. Also, this is a very abundant genus with over 100 species, almost all of them neo-tropical, so there may be other candidates for an ID as well.

-This spider looks VERY similar to the one pictured in this thread although I am not sure if this species is in the South America range.
Micrathena pungens
http://upload.wikimedia.org/wikipedia/commons/8/8c/Micrathena.pungens.-.tanikawa.jpg

Here is a link to a document stating new species in the genus Micrathena:
http://www.americanarachnology.org/JoA_free/JoA_v32_n2/arac-032-02-0332.pdf

I hope that information helps in some way or another.. Good Luck!!