Snail dying or mating?

[Alex.M.]

I got these mexican turbo snails roughly 5 days ago. They have all been extremely active and moving constantly. After dinner I found my largest snail upside down with another snail crawling on it. I flipped him right side up and watched as he flipped him self over again. The large snail is active moving around while upside down and pooping. The smaller snail seems to be leaving white dots on the flesh of my larger snail. I have attached a picture.

When I moved closer, his foot curled up like in the picture but when I watch from the distant, hes moving around, mainly on the smaller snail. The picture cant show size, but the small white one is roughly .5 inches while the larger one is closer to 3 inches in diameter.

 

[Alex.M.]

So this is an update. There are mixed opinions on the internet about turbo snails ability to right themselves when flipped. I decided to chance it again and right my snail, but this time I held him against my rocks and he latched on quickly and now is crawling happy again. The other snail is still attached so I have no idea if they are mating or not.I did measure him while i held him and he is 3.46 inches across, which is far larger than he should be.