A Moldly Screwtop?

Last night I went downstairs to my basement to put a couple of wines away for safe keeping. While moving some of my other wines over to make room, I came across a Chardonnay that my wife and I had bought from a California Central Coast winery. The wine had developed mold at the base of the screwcap foil as well as the seam where the screwcap breaks off. In addition, the wine had lost about an inch of liquid compared to the bottle fills of other wines from the same winery that we bought on the trip. No other wines were affected.

I have seen mold on a cork before but never on a screw cap. It looks more like a science project or lost vegetables found in the fridge after a couple months.

I'm curious as to if anyone has seen this happen before?