Broodstock of the venerid clam Katelysia rhytiphora (Lamy) and of the Sydney cockle Anadara trapezia (Deshayes) were induced to spawn using temperature fluctuations. Larval cultures of K. rhytiphora contained D veligers (97.1±3.7 μm shell width) within 48h, umbonate larvae by day four and pediveligers by day 11. On day 12, pediveligers (198.3±5.39 μm shell width) were placed on settlement screens and allowed to metamorphose over the following 9 days. Larvae of A. trapezia developed to D veliger stage (92.0±3.3 μm shell width) after 48 h and had reached pediveliger (approx. 220 μm) on day 14, at which time they suffered catastrophic mortality.