ID Please ¿Mammillaria or Coryphantha?

Most Coryphanthas have a groove all or part of the wat from the areole to the axil, and some have pronounced glands in the axil.So I think its a Mamm, but not sure which species yet. I'll try to get back to you in a bit.

Thanks Chris, very kind.
I also think it is a Mammillaria.
Could it be a sheldonii (pseudoalamensis-marnierana)?
The main stem is 12 cm high and 5 in diameter
Latex free

That did cross my mind, but (and I'd need to check in my greenhouse in he morning) I think marnierana has only one central spine. Its overall shape you suggest something like sheldonii. I have two or three sheldonii variants with short straight central spines, but I think they all have just one. I've checked photos that I took on a field trip and I saw straight spined sheldonii variants in St Carlos Bay, east of Alamos, and near the village of Guirocoba. If they have a central spine (some didn't) there was only one. But with such variability, who knows. I guess its never flowered for you yet?

It is new in the collection, I still don't know the flowers.

Could be M. multidigitata or M. armillata?