Reproduction in Tasmanian populations of Heliocidaris erythrogramma (Echinodermata : Echinometridae)

Abstract

H. erythrogramma sampled during 1974 and 1975 in eastern and south-eastern Tasmania showed asynchronous summer spawning. Most spent urchins were found during the early autumn. Recovering spent gonads, with abundant eosinophilic nutritive cells, were common during the winter and active regeneration was seen in late winter and spring. A clear cyclical pattern of gonad indices was not evident.

The smallest specimen in which sex could be determined by histological examination of gonads was 2.3 cm in test diameter although the urchin probably first spawns when 4-5 cm in diameter.

Gonad colours ranged from yellow to black and this did not relate clearly to gametogenic stage; lighter-coloured gonads were, however, usually larger than those of darker colour.