Piskawhat?

I’m getting buried alive under an avalanche of spam. Most of the offending items appear to start with the nonsense word piskasosiska, plus a unique numeric code that appears to correspond to the contents of the spam message. Presumably this is to make it easier to verify the spread of a particular unsolicited spam comment.

Anyone got any idea which bot network is sending these messages? I want them gone, and I’m about a heartbeat away from shutting comments down on this site entirely.