What's wrong with this lens?

I have what I thought was a nice copy of a F 35-70.

Armed with a torch I spent some time peering at my lenses (Sad I know!)and noticed the 35-70 had a problem. It appears to affect a lens element behind the front glass. It doesn't look like the fungus I've come across before.
Looking through the lens without the torch I didn't notice anything unusual.

I've taken a couple of pictures from the front and behind. Also attached a quick shot taken as a test image.

Is this fungus or a different problem?

Thanks
Sam

Humidity?

I took a lens from a coold Cornwall into the tropical Biome at Eden.

The patterns in the condensation were very wroyying.
The lens looks crystal clear to the naked eye.

Following your suggestion I popped it on a radiator for a while but there doesn't seem to be any improvement.
I'll keep an eye on it.

Wrap it in a shed load of those silica crystal bags all confined in a sealed plastic bag. The silica will draw out any moisture, don't put it on a rad, this will make the moisture condense into water droplets and screw the lens.
I know, I did it to a DA*50-135
It was insured though

And then put the bag somewhere warm

To be pedantic, putting the lens on a rad won't make the water condense at all, on the contrary it will do the opposite. However if you then cool down the lens before the nicely evaporated water has been extracted it is indeed then going to condense all over the lens innards.