Which Exotics?

Hi dendy,
First is Echinocereus as is the second and third, I'm not sure about the exact naming as they were grown from packets of mixed seed.
Third is a lobivia and the last is notocactus ottonis.
They are all easy to grow and flower, along with rebutia which really grows like a weed and self seeds in pots of other plants but flowers in spring in all shades of red/orange white or yellow.