Life history of Mytilocypris henricae (Chapman) (Crustacea: Ostracoda) in Lake Bathurst, New South Wales

Abstract

The life history of the halobiont ostracod M. henricae was studied over a 2.5-year period in Lake Bathurst, a slightly saline lake in New South Wales. Samples were collected monthly or bimonthly between March 1981 and May 1982 and weekly between August 1982 and June 1983. Relative abundance of all nine life stages (eight larval stages and one adult stage) in the samples was determined. Furthermore, in 10 selected monthly samples, sex-ratio, relative abundance of three female maturity stages and number of eggs in uteri of ovigerous females were monitored.

Nearly all life stages were present throughout the year and M. henricae is thus a perennial form in Lake Bathurst. Relative abundance of life stages suggests that M. henricae produces three successive generations per year. The spring generation, hatched from eggs laid during winter, matures around November-December. Its larval development takes between 4 and 5 months. The summer generation matures after a larval development of 2.5 months; this short period is ascribed to more favourable temperatures. The autumn generation takes about 4 months to mature.