Life History

Grows exponentially in which the instantaneous growth rate is proportional to the body mass which has been achieved. An acceleration of the absolute growth rate is reflected in a concave growth curve, growth is slow initially and accelerates as mass increases. Has very low growth rates (Yamaguchi 1977).

Juvenile life span estimated to be about 2 years from metamorphosis to transformation into the pin-cushion form. Initial juvenile size 0.5mm in diameter, about 18μg underwater weight. Transform to adult at a certain size (about 50mm in arm radius). Average newly formed adult is about 23g underwater. Metamorphoses from a flat pentagon-like juvenile into the pincushion shaped adult. Takes about 6.5 months to grow from 18 μg – 1g, about 9.6 months to grow 1g -6g and about 8.7 months from 6g – 23g. Unknown if newly formed adult is sexually mature. Total lifespan unknown, hypothesised to be long. (Yamaguchi 1977)

Larvae lives a pelagic life style, showing negative geotaxis during this life span (Yamagutchi 1977).