Spiny cactus

Thanks to all those kind people who favorited my sunrise on 26th. I will try to catch up with you, but today has been busy. I've just had time to try one or two macros of this Stenocactus in our conservatory, although I believe it may have changed its name. The systematics of cacti seems to be very much in flux, and it is difficult to get a definite name on species.