What you have there is Polystyrene sp. iupac.. It seems to have caught a bee ( species unknown) it's very rare to catch polystyrene feeding in the wild..
When disturbed they can jump 30ft and rip a mans arm off before he has time to blink... I'm amazed you walked away from this encounter unharmed.. It must of sensed that you are a beast of un paralled strength and agility..