Abstract:The paddy spider is one of the primary predators of rice pests—accounting for around 51.2% to 89.5% of the total kinds of predators in paddy fields. The paddy ecosystem is complex and unstable because of climate variation and the activities of living organisms and human beings. The paddy spiders must endure starvation periods because the populations of their prey are occasionally reduced in a large amount by the cold climate in winter or by farming activities like spraying chemicals, gathering, plowing and so on. Studying the starvation endurance of the paddy spider can provide more detailed and precise parameters for protecting and utilizing them. This paper focuses primarily on the starvation endurance of Ummeliata insecticeps (Boesenberg et Strand), which is common in most rice-planting areas in China. The results show that the survival time of U. insecticeps and the variation among individuals are positively related with the spider′s instar age at 35, 25℃ and 15℃, but negatively related at 5℃. In addition, both the survival time and the variation among individuals of all test groups increased greatly at 5℃. Whereas the differences of survival time among the three instar-groups are insignificant (p>0.05) at 35℃ and 5℃, the survival times of the three instar-groups are significantly different (p<0.05) at the favorable temperatures of 25℃ and 15℃. Temperature influences the spider′s starvation endurance greatly. The survival time of a certain instar-group that lived in one kind of temperature is greatly different from that of the same instar-group at any other kind of temperature (p<0.01). There is a close relationship between the stage-mortality (M) and the survival time (T) of U. insecticeps in starvation. It can be fitted with a normal distribution model:M=[SX(]1[]σ[KF(]2π[KF)][SX)]•e-[SX(](T-μ)2[]2σ2[SX)]. The starvation endurance thresholds and lethal times of different U. insecticeps instar-groups can be calculated according to the equation of the normal distribution model.