Spider mum

A spider mum was a variety of chrysanthemum flowers native to Earth, characterized by long, skinny petals resembling a spider's legs.

Nancy Conlon brought a spider mum to Fabian Stevens's sickbay room while he was suffering from the effects of the Ardanan parasite which had infected him in 2377. The death of the flower several days later inspired Dr. Sarjenka to propose a way of killing the parasite.