Sempervivum arachnoideum, the cobweb house-leek,[1] is a species of flowering plant in the family Crassulaceae, native to European mountains, in the Alps, Apennines and Carpathians. Growing to 8 cm (3 in) tall by 30 cm (12 in) wide, it is a rosette-forming succulent perennial, valued in cultivation for its ability to colonise hot, dry areas via offsets.[2]