There is actually already an automated way to identify/remove spam when it hits our site.
It's a bot called Smoke Detector that currently has an accuracy threshold of 99.75%. So, most spam is dealt with automatically and the ones that get through don't last very long.
To help Smoke Detector fight spam, you may want to consider signing up to give Smoke Detector access to flagging spam posts with your account. This is totally safe (I've done it myself).
However, if you don't feel comfortable doing this, you can flag spam posts manually (as you did in this case) and usually find they're gone pretty quickly.
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