that's quite a rockin' pellicle. I don't have experience with bugged beers so I couldn't say exactly, but i think this kind of 'skin' usually is a combination of aerobic bacteria and non-traditional yeasts.
It's sat atop a small (1 litre) jar of spent trub / old beer. Very little residual sugar in it when I'd set out to capture something wild so I'm half hoping it's pediococcus... I'll use it to seed a lambic beer in the autumn.