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Energy allocation strategies have been widely documented in insects and were formalized in the context of the reproduction process by the terms 'capital breeder' and 'income breeder'. We propose here the extension of this framework to dispersal ability, with the concepts of 'capital disperser' and 'income disperser', and explore the trade-off in resource allocation between dispersal and reproduction. We hypothesized that flight capacity was sex-dependent, due to a trade-off in energy allocation between dispersal and egg production in females. We used Monochamus galloprovincialis as model organism, a long-lived beetle which is the European vector of the pine wood nematode. We estimated the flight capacity with a flight mill and used the number of mature eggs as a proxy for the investment in reproduction. We used the ratio between dry weights of the thorax and the abdomen to investigate the trade-off. The probability of flying increased with the adult weight at emergence, but was not dependent on insect age or sex. Flight distance increased with age in individuals but did not differ between sexes. It was also positively associated with energy allocation to thorax reserves, which increased with age. In females, the abdomen weight and the number of eggs also increase with age with no negative effect on flight capacity, indicating a lack of trade-off. This long-lived beetle has a complex strategy of energy allocation, being a 'capital disperser' in terms of flight ability, an 'income disperser' in terms of flight performance and an 'income breeder' in terms of egg production.

Several pine bast scales (Hemiptera: Matsucoccidae) are important pests of pine trees in the Northern Hemisphere. Some species are invasive and cause significant economic and environmental impacts. Such is the case with Matsucoccus feytaudi Ducasse, an invasive pest of maritime pine forests in Southeastern France, Italy, and Corsica. The ladybird Iberorhyzobius rondensis (Eizaguirre) is a recently described species that is endemic to the Iberian Peninsula and is a potential candidate for the biological control of M. feytaudi. However, little is known of the biology of I. rondensis. As part of the risk assessment study for a classical biological control program, the phenology and reproductive mechanisms of the beetle were analyzed. I. rondensis is univoltine and is seasonally synchronized with the phenology of the prey M. feytaudi, which is also univoltine. An obligatory reproductive diapause of 5-6 mo and the need to feed on the eggs of the prey to begin oviposition emerged as the two primary mechanisms that assure life cycle synchronization of the ladybird with its prey. Female fecundity was also higher when the ladybirds were fed M. feytaudi eggs. Life cycle synchronization with M. feytaudi and reproduction triggered by consumption of prey eggs indicate that I. rondensis is a promising biological control agent of the pine bast scale., (© The Authors 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)

Specialization is an important attribute of a biological control agent. The maritime pine bast scale, Matsucoccus feytaudi Ducasse (Hemiptera Matsucoccidae), is an invasive species in Southeast France and the North of Italy. Iberorhyzobius rondensis Eizaguirre (Coleoptera: Coccinellidae), is a recently described ladybird species. Both adults and larvae are predaceous, feeding on egg masses of M. feytaudi, and are strongly attracted to M. feytaudi's sex pheromone. To evaluate the potential of I. rondensis as a biocontrol agent of the scale, we studied its niche breadth and prey range with emphasis on pine forests and hemipterans as tested prey. In this study, I. rondensis was found to achieve complete development only when fed on M. feytaudi egg masses (92.9% survival) and an artificial prey: eggs of Ephestia kuehniella Zeller (27.6% survival). From the 2nd instar onwards, complete development could be achieved using other prey species, although larvae had significantly higher mortality and slower development. In choice tests, M. feytaudi was the preferred prey. Surveys of the ladybird populations in the Iberian Peninsula revealed that it was found exclusively on Pinus pinaster Aiton, the sole host of M. feytaudi. The unusual specialization of I. rondensis, among other predaceous ladybirds, makes it an appropriate candidate for classical biological control of M. feytaudi.

During the last decades, an increasing number of predators were found to use specific prey pheromones as chemical cues. Beyond its ecological relevance, this knowledge has practical applications on insect conservation and pest control. In this study, we present first evidence that two species of the family Dasytidae (Coleoptera) Aplocnemus brevis Rosenhauer and A. raymondi Sainte-Claire Deville use the sex pheromone of the pine bast scale Matsucoccus feytaudi Ducasse (Hemiptera: Matsucoccidae) as kairomone to locate this prey. The feeding habits and biology of Aplocnemus species are practically unknown. In the laboratory, the adults of Aplocnemus sp. accepted M. feytaudi egg masses as food source as well as other diets. Females represented more than 90% of Aplocnemus sp. attracted to the pheromone lures. We believe that females use this olfactory cue to locate suitable places for oviposition and that larvae are the predators of Matsucoccus. This study further demonstrates that the response to the kairomone elicited short prey searching times, about 23% of the individuals appeared less than 12 min after lure exposure, being consistent with the hypothesis of prey specialization. Habitat and geographical distribution predict an ancestral association of A. brevis with M. feytaudi and of A. raymondi with M. pini. Nevertheless, a recent prey shift of A. raymondi to the invasive M. feytaudi in Corsica is in progress.