The shells of juvenile queen conches are strikingly different in appearance from those of the adults. Noticeable is the complete absence of a flared outer lip; juvenile shells have a simple sharp lip, which gives the shell a conical or biconic outline. In Florida, juvenile queen conches are known as "rollers", because wave action very easily rolls their shells, whereas it is nearly impossible to roll an adult specimen, due to its shell's weight and asymmetric profile. Subadult shells have a thin flared lip that continues to increase in thickness until death.