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Several traits are useful for identifying life-style types of predaceous phytoseiid mites when either 2 (diet generalist-specialist) or 4 (specialist I and II-generalist III and IV) type models [McMurtry J.A. and Croft B.A. 1997. Annu. Rev. Entomol. 42: 291-321] are considered. Traits useful for both models are developmental time and oviposition rates when feeding on several food types. Discriminating for the 2-types model are dorsal shield setae lengths, and intra- and inter-specific predation. Another trait useful for both models is feeding preferences of adult female phytoseiids on eggs versus larvae of Tetranychus urticae Koch. In this paper, we review established and other traits that need more study such as mouthpart types, other morphological features, spider mite webbing effects, distributions relative to prey-foods, plant-host relationships including domatia and sap feeding, density-dependent responses to prey and predator-prey ratios required for biological control. Uses of life-style data in biological control decision-making are discussed.

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We investigated how environmental variables influence development and survivorship of Boreioglycaspis melaleucae Moore (Hemiptera: Psyllidae) by quantifying life history characteristics of adults, eggs, and nymphs when held at eight constant temperatures, four relative humidities, and on plants that differed in foliar terpenoid profiles. There is insufficient evidence to conclude that terpenoid profiles or humidity influence B. melaleucae development. Although longevity of adult psyllids is greater on plants that contain E-nerolidol versus viridiflorol profiles, this does not translate to a longer ovipositional period or increased fecundity. Similarly, humidity treatments had a limited and inconsistent effect on B. melaleucae developmental rates and nymphal survivorship. In contrast, developmental rates increased linearly with increasing temperature to an optimum 25°C, whereas greater temperatures caused total developmental rates to decrease. Temperature also affected nymphal survivorship, with no individuals completing development below 10 or above 30°C. Mean maximum daily temperatures in southern Florida commonly exceeded 30°C, with maximum temperatures ranging from 30 to 35°C (in Broward Co.) during 138 d in 2006. Therefore, we conclude that lethal upper temperature thresholds will limit population growth rates during summer.