Any one no what this is

Did a karndean bathroom today and got asked to take a look at the kitchen floor to see if I new what was up with it there's about 40sq meters like this but the hallway that's about 20 is fine solid floor underneath there all down tight as a drum

 

Is it a concrete subfloor?
looks like hairline cracks in the subfloor shadowing through?

 

im noticing a lot of direct sunlight in the pics
Possible that if it is a concrete floor that the screed has set too quick with the sunlight and cracked, but theyve not skimmed the cracks?

 

Yep it's a solid floor never seen anything like it I just took the pictures in the light to get the best effect when you rub your hand over them they are quite deep

 

latexed over a cracked floor but not filled in cracks first so it's all dropped through

 

Surely thats too much to be just cracking of the latex, there has to be an underlying problem thats caused it, is it raised up/bubbling? could it be mastic asphalt bubbling from moisture?

 

I like it

 

The house was a 1.2 million pad it's only done it in the kitchen not in the hallway that's spot on there's no bubbling or raising up it like someone's been over it with sack truck but there's far to much of it to be anything like that was just interested to see if any one new what could be

 

Someone played bumper cars with piano's

 

Could be one of those screed beetles, Latin name is whatthehellisthat, it's related to the wood boring beetle, Wood worm. Seems very keen on new enhanced quick drying screeds.
Been seeing a lot of it in and around the London area, could be getting imported from Eastern Europe and moving north!