Strongylocentrotus purpuratus (Stimpson 1857)

Maximum longevity: 50 years Observations: Even though the purple sea urchin has been an important model for biomedical research, its ageing process has not been studied in detail. Based on growth rates, it has been estimated that these animals can live over 50 years (Ebert 1967). Since evidence suggests that the red sea urchin (*Strongylocentrotus franciscanus*) is extremely long-lived with no detectable signs of ageing, the purple sea urchin may also be extremely long-lived and its maximum longevity may be considerably underestimated.