The scientific classification of Hymenocephalus rigidus is kingdom plantae, order asterales and family asteraceae which is a family of flowering plants in the daisy family.
Kingdom: Plantae Order: Asterales Family: Asteraceae Asteraceae or Compositae (commonly referred to as the aster, daisy, composite, or sunflower family), is a very large and widespread family of flowering plants (Angiospermae). Hymenocephalus is a genus of flowering plants in the daisy family. 
