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Among phytophagous insects, life history often evolves as a strategy to cope with seasonality in host plant availability. Whereas specialization often leads to dormancy, aestivation, or longevity, polyphagous species bridge between periods of host availability by exploiting alternative host plants. The aim of the present work was to characterize the life histories of four species of specialist and generalist uni‐ and multivoltine frugivorous fruit flies – Ceratitis capitata Wiedemann, Anastrepha fraterculus Wiedemann, Rhagoletis blanchardi Aczel, and Rhagoletotrypeta pastranai Aczel (all Diptera: Tephritidae) – inhabiting in sympatry in Las Yungas phytogeographical province in Tucumán (northwestern Argentina). For this purpose, infested host plant fruits were sequentially collected during two consecutive years, and flies recovered from these fruits were subjected to demographic experiments to establish longevity and overwintering mechanisms. The results indicated that life cycles were tightly related to host fruit availability, where multivoltine species sequentially exploit different host plants over the year, whereas univoltine species must undergo pupal dormancy to reach the next host fructification period and may extend the duration of dormancy when climatic conditions are acyclic and unpredictable. The present study may broaden knowledge about diapausing Tephritidae in subtropical regions and may contribute to an increased conceptual basis for the improvement of pest control strategies, such as the sterile insect technique (SIT). [ABSTRACT FROM AUTHOR]

Ceratitis capitata is the most serious agricultural pest in Argentinean fruit-growing regions. The use of baited traps for Medfly control is an expanding and increasingly successful integrated management strategy. The high cost of traps and attractants is one of the main limitations for use on either a massive scale or a small-scale control. This study aimed to evaluate the advantages or disadvantages of using natural fruit juice-based lures for Medfly adult monitoring at the orchard level in an irrigated valley. Medfly capture with a standard protein attractant was compared with peach, apple, sweet orange, fig, and grape juices. All attractants were evaluated in 1.5-liter disposable plastic bottles that served as traps. The most relevant finding was the interaction between attractant effectiveness and season. While the standard yeast was the most effective attractant during summer, the highest Medfly caught values recorded during both spring and autumn were achieved with traps baited with orange juice. The use of fruit juices as attractants and disposable bottles as traps can decrease the impact on non-target insects and reduce management costs. [ABSTRACT FROM AUTHOR]

Promiscuous mating systems provide the opportunity for females to bias fertilization toward particular males. However, distinguishing between male sperm competition and active female sperm choice is difficult for species with internal fertilization. Nevertheless, species that store and use sperm of different males in different storing structures and species where females are able to expel all or part of the ejaculates after copulation may be able to bias fertilization. We report a series of experiments aimed at providing evidence of female sperm choice in Euxesta eluta (Hendel), a species of ulidiid fly that expels and consumes ejaculates after copulation. We found no evidence of greater reproductive success for females mated singly, multiply with the same male, or mated multiply with different males. Female E. eluta possesses two spherical spermathecae and a bursa copulatrix for sperm storage, with a ventral receptacle. There was no significant difference in storing more sperm in spermathecae 24 h after copulation than immediately after copulation. Females mated with protein‐fed males had greater reproductive success than similar females mated to protein‐deprived males. Protein‐fed females prevented to consume the ejaculate, retained more sperm when mated to protein‐fed males than when mated to protein‐deprived males. Our results suggest that female E. eluta can exert control of sperm retention of higher quality males through ejaculate ejection. [ABSTRACT FROM AUTHOR]

Endosymbiont‐induced cytoplasmic incompatibility (CI) may play an important role in arthropod speciation. However, whether CI consistently becomes associated or coupled with other host‐related forms of reproductive isolation (RI) to impede the transfer of endosymbionts between hybridizing populations and further the divergence process remains an open question. Here, we show that varying degrees of pre‐ and postmating RI exist among allopatric populations of two interbreeding cherry‐infesting tephritid fruit flies (Rhagoletis cingulata and R. indifferens) across North America. These flies display allochronic and sexual isolation among populations, as well as unidirectional reductions in egg hatch in hybrid crosses involving southwestern USA males. All populations are infected by a Wolbachia strain, wCin2, whereas a second strain, wCin3, only co‐infects flies from the southwest USA and Mexico. Strain wCin3 is associated with a unique mitochondrial DNA haplotype and unidirectional postmating RI, implicating the strain as the cause of CI. When coupled with nonendosymbiont RI barriers, we estimate the strength of CI associated with wCin3 would not prevent the strain from introgressing from infected southwestern to uninfected populations elsewhere in the USA if populations were to come into secondary contact and hybridize. In contrast, cytoplasmic–nuclear coupling may impede the transfer of wCin3 if Mexican and USA populations were to come into contact. We discuss our results in the context of the general paucity of examples demonstrating stable Wolbachia hybrid zones and whether the spread of Wolbachia among taxa can be constrained in natural hybrid zones long enough for the endosymbiont to participate in speciation. [ABSTRACT FROM AUTHOR]