to think this could be signs of a mould infestation? (pics included)

[Peanutters]

Been hiding out in the family's coastal house (you can only begin to imagine the humidity levels), and I've just noticed this in the corner of one of the rooms after having the air-conditioning switched on 24/7 since I came here.

I've surmised that this water mark comes from some sort of condensation issue on the insulation pipes (might have to get that changed soon). My primary concern however, is whether this is a sign of a mould infestation? Second picture (area to the right of air-con in picture 1 taken from a "bottom view") is taken in the dark with a yellow flash, but the greenish "spots" can still be seen.

What's a mould infestation?

Mould is everywhere and thrives where there is damp.

You have air con making the house cold in a very humid area. Surely every day is a battle against mould? Just bleach it

It looks as though there may be a leak - there's what looks like a boxed in pipe around the area.

Looks more like water stains from a leak than mould.

Difficult to tell from the pictures, but looks more like green algae than mould. So if sun is shining on a wet area? Or as caffeinestream says, stains from a leak.

Looks like a leak to me too.