Calla lily (Zantedeschia aethiopica) is a rhizomatous herbaceous perennial plant which is grown outdoors in mild climates and often kept as a houseplant elsewhere. The plant has smooth-edged, arrow-shaped leaves and showy flowering spathe which varies in color from white, green, pink or yellow.
The leaves of this plant contain raphides, which are tiny, needle-shaped crystals made up of calcium oxalate. When the plant tissues are damaged, the raphides shoot out the idioblasts, which act like tiny needles, cutting into the lining of the mouth, esophagus, and/or gastrointestinal tract of the bird. Since raphides also contain toxic proteins, the lacerations made by the raphides allow these compounds to enter through the wounds, causing intense pain and harm to the surrounding tissues.