astrophytum myriostigma - rare species of thornless cactus in a botanical collection

astrophytum myriostigma bishop 039 cap cactus thornless rare species botanical collection succulent plant desert flora mexico star flowering ornamental xerophyte caryophyllales cactaceae magnoliopsida tracheophyta plantae cultivation ribbed areoles starshaped droughttolerant spines areole fleshy perennial exotic decorative houseplant landscape geometric symmetry natural green blooming cactoideae cacti cacteae asterias nudum