Abstract
Field and laboratory data for the larval development and life-cycles of three algal-living ostracod species from the Øresund are compared. The larval development of Xestoleberis aurantia (Baird) was found to take 60 days at a temperature of 20°C and 90 days at 12-15 dc. At 10°C the larvae died after hatching. Semicytherura nigrescelis (Baird) hatched 6-8 days after egg deposition at 2024° C and 16-18 days at 10 dc. The larvae grew to maturity in 35 and 60 days, respectively. Hemicytherura cellulosa (Norman) took 10-15 days to hatch and reached maturity after another 45 days at 20-24 DC, while it took 60 days at 10°C.