white cactus flower with yellow stamens and pistil in the botanical collection, odessa

cactaceae cactus cacti plant succulent bloom flower white nature botany collection desert xerophyte flora species genus taxonomy ecology horticulture greenhouse dry arid spines thorns biodiversity macro closeup prickly ornamental bloomtime growth xerophyteplant exotic environment rare decorative succulents cultivated specimen biology conservation ecosystem wildflower landscaping cacteae