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Black Spider with Red Dot

Where is the "dot" on the black spider? Are you sure it's a dot and not an ...
http://www.chacha.com/question/what-spider-is-blac...
a pimple with black heads?
http://uk.answers.yahoo.com/question/index?qid=201...
This sounds like a black widow, so stay away
http://www.blurtit.com/q5605111.html
It is probably a Black Widow spider. If the underside of it's abdomen has 2 red triangle shapes that look like an hour glass, it is definately a Black widow and is poisonous.
http://www.blurtit.com/q4511567.html
Sounds like a widow spider so probably.
http://www.blurtit.com/q2636235.html
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Black Spider with Red Dot

I Googled "spider with red dot on back" and came up with this link, which I think has your answer: http://wiki.answers.com/Q/Black_fuzzy_sp…
answers.yahoo.com
Featured are the brown recluse, black widow, hobo spider, wolf spider, ... color from yellowish orange to red and its shape may range from an hourglass to a dot.
www.termite.com
The black widow spider is perhaps the best-known member of the genus. ... top of the abdomen — some may have a pair of red spots or have no marking at all.
en.wikipedia.org