Cacti Identification

Not sure what this little guy is, or how to properly care for him!
Any help would be appreciated - many thanks in advance.

 

Fenestraria. Sweet little thing. Not too much water, diluted feed. Do this every couple of weeks in summer, once a month in winter if at all. Do not let it sit in water.
They have unusual lacy petals on their flowers. Very nice.

 

It is a Fenestraria

You will need to see the flowers to narrow it down to one of the 2 species
rhopalophylla has white flowers
aurantiaca has yellow flowers

If I remember correctly the yellow species is found in the Richtersveld in SA, south of the Orange River
And the white is from north of the Orange River in Southern Namibia

Sew,
If you want your plant to flower, it will need as much sun as possible.