none A field study was undertaken to determine the phenologies of the solitary larval endoparasitoids Cotesia urabae and Dolichogenidea eucalypti in relation to that of their bivoltine host Uraba lugens. C. urabae had two generations within both the summer and the winter generation of U. lugens , and D. eucalypti had two generations in the summer but only one generation in the winter. D. eucalypti parasitised a narrower range of host sizes in the field. Both parasitoids attacked recently hatched (typically 1st instar) or "small hosts" at the beginning at each host generation. In summer D. eucalypti was the first to emerge from hosts, but both D. eucalypti and C. urabae , emerged from hosts which had modes of 0 multiplied by 85-1 multiplied by 05 mm in head capsule width and 0 multiplied by 9-1 multiplied by 5 mg in dry weight (mid hosts). In winter, C. urabae emerged from hosts which had modes of 1 multiplied by 15 mm in head capsule width and 2 multiplied by 7 mg in dry weight (large hosts).