Abstract
The growth and the reproduction of the spider crab, Tiarinia cornigera was investigated at the Banda Marine Laboratory of Tokyo University of Fisheries. Chiba prefecture, and the outline of the life history was determined. The larvae of T. cornigera hatch in June to September, and metamorphose to juveniles crabs in 7 to 10 days. The juveniles grow rapidly in autumn. In winter the growth stagnates, but in spring again they grow rapidly. In June to July the puberty molt which is also the terminal molt occurs, with the development of the second sexual characteristics. Soon they mate and spawn. In a reproductive season a female spawns 4 to 6 times. At about 20 days after spawning the larvae hatch and a further brood deposited. In autumn the most of adults finished breeding are die out. It is suggested that the life span of T. cornigera is about one year in this study area.
