Did anyone mention that there is, to date,
no "Spyware" for the Mac?
So, by definition, there is no "antispyware" for the Mac. That answers the original question.
And you can be certain that, should any Spy loophole become evident, Apple will be quick to issue a security update. Unlike Microsoft, Apple is not bogged down with thousands of malware problems already, so its reaction time is likely to be much better.
Should you wish to keep track of outgoing traffic, however, then software such as Little Snitch will cheerfully interrupt your work pattern and add to your paranoid worries.
