Chrysanthemum species that is used for extraction of Pyrethrum is

Chrysanthemum species that is used for extraction of Pyrethrum is C. cinerarifolium.
Pyrethrum is the name of the crude extract obtained from flowers of this plant.
Pyrethrum is used as an insecticide for scabies, head lice, crab lice and their nits. The active chemicals, the Pyrethrins, are toxic to insect nervous systems.