Carlo Polidori

University of Milan | UNIMI · Department of Environmental Science and Policy – ESP

Highlights •Torymus sinensis can attack native species under laboratory and field conditions. •Molecular and mating data show that there is no hybridization with the native species. •We detected the presence of the alien species Torymus beneficus in Spain. •Decisions on biological control of D. kuriphilus by T. sinensis are discussed. BACKGROU...

The effects of the maternally-inherited intracellular bacteria of the genus Wolbachia on insect physiology remain obscure for many hosts. Here, we report a link between the infection of Wolbachia of supergroup A and the cuticular hydrocarbon (CHC) profile in the parasitoid wasp Myrmilla capitata (Lucas) (Hymenoptera: Mutillidae), providing the seco...

Background Brood parasites can exert strong selection pressure on their hosts. Many brood parasites escape their detection by mimicking sensory cues of their hosts. However, there is little evidence whether or not the hosts are able to escape the parasites’ mimicry by changing these cues. We addressed this question by analyzing cuticular hydrocarbo...

1. Bees provide important ecosystem services and are subjects of extensive studies on their α-diversity, which is generally calculated with indices that integrate the number of species with their abundances. Variation in social behaviour, though expected to impact genetic diversity, is still largely neglected in such studies. 2. We propose a simple...

Despite growing interest in gut microbiomes of aculeate Hymenoptera, research so far focused on social bees, wasps and ants, whereas non-social taxa and their brood parasites have not received much attention. Brood parasitism however allows to distinguish between microbiome components horizontally transmitted by spill-over from the host with such i...

Urbanization is one of the main causes of natural habitats alteration. Particularly, urbanization is associated with a reduction and fragmentation of green areas and an increase in temperatures, in a phenomenon called “Urban Heat Island Effect” (UHI). Wild bees and wasps (Hymenoptera) can be affected by – or adapt to - these changes by shifting som...

Land-use change, including urbanization, is known to affect wild bee (Hymenoptera: Apoidea) diversity. However, while previous studies have focused on differences across local urbanization gradients, to the best of our knowledge, none focused on differences among cities at a wide geographical scale. We here used published data for wild bee communit...

List of wild bee species recorded in the analysed studies, togheter with their functional traits

Microplastics (MP) are ubiquitous contaminants of great concern due to their high persistence and potential hazardous impact on the environment. Depending on their size and shape, as well as the chemical additives they can have in their polymeric structure, MP can be taken up by organisms, ultimately leading to direct and indirect toxic effects. In...

Insect sensory systems are the subjects of different selective pressures that shape their morphology. In many species of the flesh fly subfamily Miltogramminae (Diptera: Sarcophagidae) that are kleptoparasitic on bees and wasps, females perch on objects close to the host nests and, once a returning host is detected, they follow it in flight at a fi...

Hymenoptera evolved structures on the legs which are able to remove particles from their antennae through grooming behaviour. The antenna cleaner (strigil) consists of an apical and modified protibial spur (calcar, composed of a trunk and a velum) and a modified basitarsus including a fine comb made up of setae and a notched inner surface. In "Tere...

Background Pistachio (Pistacia vera L.) is a commercially important tree in the Mediterranean basin, where is showing a considerable increase in cultivation, especially in Spain. Because of its recent introduction as a crop in the country (1980s), studies on the pests of pistachio in Spain are still rare. Here, we studied the leaf beetle Labidostom...

Insects are highly involved in accidental introductions in non-native areas. Potential distribution modelling is routinely used to predict the dynamics of such range expansions, giving insights on which areas are climatically suitable for establishment. However, even in areas where climatic conditions are unsuitable, colonization may be still possi...

Sicily (Italy) is an important hotspot diversity for bees and new species records are constantly reported for the island. Here, we rediscovered after 45 years without records, the occurrence in Eastern Sicily of Lasioglossum marginatum (Brull e 1832) confirmed by DNA barcoding. This is the only known species of eusocial sweat bees (Halictidae) with...

Pollinators of most of the plants cultivated in the Mediterranean regions of Europe are still unknown. We provide new data and we review previously available information on bees (Apoidea) associated with three economically important crops in Spain: melon (Cucumis melo L.), watermelon (Citrullus lanatus (Thunb.) Matsum. & Nakai) and almond (Prunus d...

The wasp family Chrysididae (cuckoo wasps, gold wasps) comprises exclusively parasitoid and kleptoparasitic species, many of which feature a stunning iridescent coloration and phenotypic adaptations to their parasitic life style. Previous attempts to infer phylogenetic relationships among the family’s major lineages (subfamilies, tribes, genera) ba...

Total list of bee species collected on flowers (i.e. by netting) of melon, watermelon and almond in Spain, with locality and morpho-ecological traits.

Since alien species may threaten native ecosystems when becoming invasive, one of the main challenges is try to predict their potential spread. Despite bees are essential pollinators and provide important ecosystem services in their native areas, outside these areas they could represent a risk for the local bee fauna, e.g. by competing for resource...

Most data about parasitoids of the genus Melittobia (Hymenoptera: Eulophidae) in Europe, where only the native M. acasta (Walker, 1839) and the alien M. australica Girault, 1912 occur, come from studies carried out in the central-northern part of the continent. In the present study, we provide new information on both species in the Iberian Peninsul...

The vast majority of species of velvet ants (Hymenoptera: Aculeata: Mutillidae) are ectoparasitoids of immature stages of other aculeate Hymenoptera (bees, wasps and ants). Due to their cryptic, furtive behaviour at the host nesting sites, however, even basic information on their biology, like host use diversity, is still unknown for entire subfami...

Mating behaviour in insects is largely mediated by chemical signals emitted by one sex and recognized by the other (sex pheromones). A particular type of integumentary gland produces a sex pheromone in the antennae of male Cynipoidea (Hymenoptera), a rich and diverse wasp group consisting of species forming galls on plants, species which act as inq...

The alien cynipid wasp Dryocosmus kuriphilus Yasumatsu, 1951 is a serious pest of chestnuts ( Castanea spp.) in Japan, North America and Europe, causing fruit losses while inducing galls in buds. While D. kuriphilus galls have a recognizable and roughly invariable globular shape, their size varies, reaching up to 4 cm in diameter. Among other facto...

Among the insects inhabiting endorheic, temporary and highly saline small lakes of central Spain during dry periods, tiger beetles (Coleoptera: Carabidae: Cicindelinae) form particularly rich assemblages including unique endemic species. Cephalota dulcinea López, De la Rosa & Baena, 2006 is an endemic, regionally protected species that occurs only...

In several groups of insects, body structures related to feeding and oviposition are known to have a hardened cuticle by incorporation of transition metals. However, a functional link between metal enrichment and ecological pressures (i.e., adaptation) has been only rarely shown, opening the possibility that in some lineages, the evolutionary histo...

Several studies recently reported that specialized (oligolectic) bees, which collect pollen from few host plants, use, besides visual cues, specific volatiles to find their hosts. Generalist (polylectic) bees, on the other hand, likely have to recognize a wider range of volatiles because they forage on many plant species. Bee antennal sensory equip...

Insect brood parasites have evolved a variety of strategies to avoid being detected by their hosts. Few previous studies on cuckoo wasps (Hymenoptera: Chrysididae), which are natural enemies of solitary wasps and bees, have shown that chemical mimicry, i.e., the biosynthesis of cuticular hydrocarbons (CHC) that match the host profile, evolved in se...

Brood parasites need to overcome host detection in order to exploit their target resource. Nest invasion by brood parasites is possibly enabled either by chemical mimicry (innate odour match with host), camouflage (acquired odour match with host) and/or chemical insignificance (odour reduction). We analysed which of these strategies may be used by...

The diversity of insect antennal structures involved in communication is still poorly known because of the limited number of comparative studies and as such studies often exclusively focus on one sex. Within Cynipoidea, a recent study on female gall-wasps (Hymenoptera: Cynipidae) and some of their non-gall associated relatives (Ibaliidae and Figiti...

1. Climate change is expected to produce shifts in species distributions as well as behavioural, life-history, and/or morphological adaptations to find suitable conditions or cope with the altered environment. Most of our knowledge on this issue comes from studies on vertebrates, mainly endotherm species. However, it remains uncertain how small ect...

Before Linnaeus published the Systema Naturae, in which introduced the modern species concept, a huge amount of information on ecology, behaviour and diversity of many animals had been accumulated. This information, often extremely detailed, suffers from the lack of the assignation of the studied organisms to their modern specific names. Here, we e...

Females of the solitary digger bee Andrena florea Fabricius, 1793 (Hymenoptera, Andrenidae) nest in aggregations and collect pollen almost exclusively on dioecious plants of the genus Bryonia, making this species a good model to study the relationship between nest density, male density, male behaviour and female lecty. At a study site in the valley...

The globally spreading pest Drosophila suzukii and its relative D. subpulchrella (Diptera: Drosophilidae) possess an elongated ovipositor with enlarged bristles which is associated with their ability to oviposit into hard-skinned fruits. Other species of the genus ovipositing in damaged fruit and decaying material have blunt ovipositors with small...

The chestnut gall wasps, Dryocosmus kuriphilus Yasumatsu (Hymenoptera: Cynipidae), a species native of China, has been introduced accidentally in many countries and it is now considered as a major pest of Castanea species worldwide. After being detected for the first time in Spain in 2012, the species spread very quickly and its is now present in e...

Se estudia por primera vez la abundancia y diversidad de Hymenoptera, y se presenta un inventario preliminar de este grupo de insectos, en el área de “Huinay” perteneciente a la Fundación San Ignacio del Huinay en el fiordo Comau de la X región de Chile (Los Lagos) en el norte de la Patagonia chilena. Se efectuaron muestreos en dos periodos de dos...

Aim of study: The globally invasive gall wasp, Dryocosmus kuriphilus Yasumatsu, 1951 (Cynipidae: Cynipini), reached Spain seven years ago and is already regarded as an important pest of chestnuts (Castanea spp.) in this country as well as worldwide. In this paper, we present comprehensive data on the establishment in Spain of Torymus sinensis Kamij...

Background. Predicting the patterns of range expansion of alien species is central to develop effective strategies for managing potential biological invasions. Here, we present a study on the potential distribution of the American cavity-nesting, Orthoptera-hunting and solitary wasp, Isodontia mexicana (Hymenoptera: Sphecidae), which was first dete...

Aganaspis daci es un endoparasitoide larvario de tefrítidos identificado en España por primera vez en el año 2009 sobre la mosca mediterránea de la fruta, Ceratitis capitata, por parte del equipo de entomología del IVIA. Desde entonces y dado su uso en otros países para el control poblacional de diversas especies de moscas de las frutas, se ha esta...

Polistes paper wasps can be used to monitor trace metal contaminants, but the effects of pollution on the health of these insects are still unknown. We evaluated, in a south-eastern area of Spain, whether workers of Polistes dominula collected at urban and rural sites differ in health of midgut tissue and in fluctuating asymmetry, an estimate of de...

The larval–pupal endoparasitoid Diachasmimorpha longicaudata (Hymenoptera: Braconidae) is currently the most commonly employed biological control agent against Tephritid fruit flies in the Americas. However, this parasitoid remains largely ignored and is not used in many regions, including the Mediterranean Basin. In this study, the potential of D....

The cuticle of insects is covered by a layer of hydrocarbons (CHCs), whose original function is the protection from desiccation and pathogens. However, in most insects CHC profiles are species-specific. While this variability among species was largely linked to communication and recognition functions, additional selective forces may shape insect CH...

The effect of environmental factors is essential to the success of parasitoids as biological control agents, as it determines their foraging activity, development, and survival. The larval-pupal parasitoid wasp Aganaspis daci (Weld) (Hymenoptera: Figitidae) is known to have a very low fertility (i.e., offspring production) in the field in certain M...

Patterns of coloration in queens and workers of Bombus species. (A–B) B. lapidarius lapidarius queen (dorsal-lateral) (C–D) B. lapidarius lapidarius worker (dorsal-lateral) (E–F) B. humilis_queen (dorsal-lateral) (G–H) B. humilis_worker (dorsal-lateral) (I–J) B. lapidarius decipiens_queen (dorsal-lateral) (K–L) B. lapidarius decipiens_worker (dorsa...

Raman spectra obtained from all tested individuals of Bombus. Each sheet includes the data for one specific hair color, while the last sheet includes the data for the hairless ventral side of the thorax of B. terrestris. The alternate white and grey columns in the six color-related sheets indicate different individuals.

Raman spectrum of hairless, black ventral side of thorax in B. terrestris, and peaks identification after having applied the Reference Deconvolution Method. The grey line represents the Raman spectrum, the dashed green lines represent the single deconvoluted curves, which highlight the different peaks contributing to the spectrum, and the red line...

Raman spectra of yellow hair extracts and synthetic pterin. (A) yellow hair extracts from B. terrestris (c) and associated solvents (a, acidified methanol; b, sodium carbonate), and (B) synthetic pterin (black line) and yellow hair extracts (blue line). ♦ signature peaks for pterin. Note that yellow hair extracts did not return a spectrum with neit...

Females of most aculeate Hymenoptera mate only once and males are therefore under a strong competitive pressure which is expected to favour the evolution of rapid detection of virgin females. In several bee species, the cuticular hydrocarbon (CHC) profile exhibited by virgin females elicits male copulation attempts. However, it is still unknown how...

Background Bumblebees (Hymenoptera: Apidae: Bombus) are well known for their important inter- and intra-specific variation in hair (or pubescence) color patterns, but the chemical nature of the pigments associated with these patterns is not fully understood. For example, though melanization is believed to provide darker colors, it still unknown whi...

Hymenoptera (sawflies, wasps, ants, and bees) are one of four mega-diverse insect orders, comprising more than 153,000 described and possibly up to one million undescribed extant species. As parasitoids, predators, and pollinators, Hymenoptera play a fundamental role in virtually all terrestrial ecosystems and are of substantial economic importance...

The most harmful hymenopteran pests of Pinus sylvestris L. are conifer sawflies from the family Diprionidae, including the widespread Diprion pini (L.). Natural enemies of this pest are still poorly known in many European areas where attacks occur. We studied the egg parasitoids of D. pini at four sites in two mountainous areas of Spain: the Sierra...

The fitness consequence of many behaviours of the small digger wasp, Cerceris rubida (Hymenoptera: Crabronidae), the only European species of its genus in which females share nests, are still unknown. Here, I present novel data on the nesting patterns and nest parasites of an Italian population of this wasp, with emphasis on which behavioural strat...

We describe a new species of Corynura Spinola, a socially polymorphic genus within the bee tribe Augochlorini (Halictidae). We present a detailed description of both sexes of Corynura (Corynura) moscosensis n. sp. González-Vaquero, images of diagnostic morphological structures and antennal sensilla, floral associations, distributional data and note...

The inclusion of Zn in insect mandibles affects their hardness and is functional to their use during feeding or reproducing. However, little is known on the chemical/structural base of Zn enrichment. Here, we found that cathodoluminescence (CL) technique revealed two different types of CL spectra in the mandibles of Hymenoptera, depending on the Zn...

1. The habitat requirements of a species are the resources, conditions and space required for survival and reproduction. The habitat requirements of butterflies have been well studied, but the extent to which individuals within a species and between species utilise and share the habitat is poorly known. 2. In a butterfly assemblage in northern Ital...

The occurrence and distribution of eumelanin and pheomelanin, the most prevalent biological pigments, has been rarely investigated in insects. Particularly yellowish to brownish body parts, which in many vertebrates are associated with pheomelanin, are visible in many insects but their chemical nature was rarely examined to a similar detail. Here,...

In prey-predator systems where the interacting individuals are both fliers, the flight performance of both participants heavily influences the probability of success of the predator (the prey is captured) and of the prey (the predator is avoided). While the flight morphology (an estimate of flight performance) of predatory wasps has rarely been add...

Rough matrices containing the data used to perform the analyses. (XLS)