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Simple Summary: Marchalina hellenica (Hemiptera: Marchalinidae) is a significant contributor to annual honey production in Greece and Turkey, where it is endemic. It was initially described as parthenogenetic, producing only females. The exact reproduction strategy of this species remains unknown. For this reason, we studied the emergence pattern of male individuals in Greece for two consecutive years (2021 and 2022). Furthermore, we examined the genetic variation among 15 geographically distant populations of M. hellenica in Greece using a mitochondrial DNA marker and compared the results with data from Turkey. This study documents the existence of an additional M. hellenica population in its native range that repeatedly produces males, suggesting a previously unknown role for males in the species' reproduction. The Greek and Turkish populations exhibited a strong genetic affinity, while the genetic pattern in Greece seems to have been obscured by human-aided dispersal. Marchalina hellenica (Hemiptera: Marchalinidae), an endemic species in Greece and Turkey, is a major contributor to the annual honey production in its native range. However, in the areas that it invades, lacking natural enemies, it has detrimental effects on pine trees and potentially contributes to tree mortality. Although it was originally reported as thelytokous, males were later reported in Turkey and on several of the islands of Greece. To further disambiguate the exact parthenogenetic reproduction strategy of M. hellenica, we studied the emergence pattern of male individuals in Greece for two consecutive years (2021 and 2022). Furthermore, we examined the genetic variation among 15 geographically distant populations of M. hellenica in Greece using a mitochondrial DNA marker and compared the results with data from Turkey. The findings of this study document the existence of an additional M. hellenica population in its native range that repeatedly produces males, apart from the areas of Greece and Turkey in which they were initially reported, suggesting that males play a major, so far unknown role in the reproduction of this species. The populations in Greece and Turkey exhibited a strong genetic affinity, while human-aided dispersal seems to have obscured the genetic pattern acquired. [ABSTRACT FROM AUTHOR]

Many recently established non-native insect species appear to be spreading across Europe significantly faster than before. The box tree moth (Cydalima perspectalis), a native to Asia, is illustrative of this trend. First recorded in 2007 in Germany, the moth has then colonized in less than 10 years more than 30 countries in Europe and Asia Minor, causing significant damage to wild and ornamental Buxus trees. It has been hypothesized that the trade of ornamental box trees between China and Europe was responsible for the moth introduction while plant trade among European countries may have caused its rapid spread. To clarify the pest invasion history, we analyzed the genetic diversity and structure of its populations in the native and invaded ranges, using a 1495-bp fragment of the mitochondrial cytochrome oxidase I and II genes. Moth genetic diversity in Asia compared to the one observed in the invaded Europe and Asia Minor suggested that the invasive populations probably originated from eastern China. Furthermore, the high genetic diversity coupled with the spatial genetic structure in the invaded range suggested the occurrence of several introduction events, probably directly from China. Moreover, the spatial genetic structure in Europe and Asia Minor may also reflect secondary invasions within invaded range because of ornamental plant trade among European countries. [ABSTRACT FROM AUTHOR]

Simple Summary: The silver fly Neoleucopis kartliana Tanasijtshuk (Diptera, Chamaemyiidae) is the most abundant predator of the giant pine scale (GPS), Marchalina hellenica (Hemiptera, Margarodidae), and is considered a major factor in controlling GPS populations in Greece and Turkey. GPS has recently been detected in Australia. While generally not harmful to trees in its area of origin, GPS has a detrimental impact on pine trees in Australia and, therefore, needs to be controlled. As part of an evaluation of the silver fly for importation to Australia where it may be used as a biological control agent against GPS, we studied several aspects of the fly's life history, namely its seasonal occurrence and number of generations per year (phenology), its acceptance of artificial food sources as adult flies, and the number of eggs females produce over their lifetime. We found that the fly has three generations per year and feeds on all life stages of GPS (eggs, nymphs, and adults). Adults readily feed on a mixture of sugar and dry yeast, and females emerge with no or few eggs and develop more as they age. Neoleucopis kartliana Tanasijtshuk (Diptera, Chamaemyiidae) is the most abundant predator of the giant pine scale (GPS), Marchalina hellenica (Hemiptera, Margarodidae) in Greece. GPS is native to Greece and Turkey, where it is not considered a pest of Pinus spp., but a valuable resource for pine honey production. However, its introduction to new areas leads to high population densities of the scale, linked to declines in tree health and insect biodiversity. To assess the potential use of N. kartliana for a classical biological control program in Australia, we studied selected life-history traits of the silver fly, namely its phenology in northern Greece, feeding preferences of adult flies on artificial food sources, and potential fecundity of female flies. The silver fly was present in every site in northern Greece studied and was found to have at least three generations per year in this area. The fly's overall sex ratio was 1:1, and adult females emerged with no or few mature eggs in their ovaries, but egg production was exponential until at least the eighth day after emergence. These findings increase our knowledge about the biology of N. kartliana and aided in the evaluation of the silver fly as a classical biological control agent against invasive GPS in Australia. [ABSTRACT FROM AUTHOR]

[Display omitted] • Leucopis hennigrata is a promising candidate for biological control of Adelges nordmannianae in Northern Europe. • L. hennigrata is a key predator of Ad. nordmannianae in Western Asia and Central Europe. • Under laboratory conditions larvae of L. hennigrata killed 57–117 eggs in 24 h. • Adult L. hennigrata oviposited on various non-target species, but rarely completed development. • Leucopis hennigrata was not found from non-target adelgids or aphids in the field. The silver fly Leucopis hennigrata McAlpine is a predator of the silver fir wooly adelgid, Adelges nordmannianae (Eckstein), a pest in the European production of Christmas trees. While the fly is known to be a common native predator of the adelgid in Georgia, Turkey, and central Europe, it is absent from northern Europe, where the Christmas tree production is an important industry. Therefore, L. hennigrata has been suggested as a classical biological control agent of Ad. nordmannianae in northern Europe. Here, we evaluated the fly's suitability as a classical biological control agent in terms of (1) differences between Asian and European populations, (2) its abundance relative to other predators of Ad. nordmannianae , (3) larval feeding efficacy, as well as (4) the physiological and (5) ecological prey preference of the fly. The results showed that despite genetic divergence between Western Asian and Central European populations, L. hennigrata is a dominant natural enemy of Ad. nordmannianae in Switzerland, the Pontic mountains in northern Turkey, and in the Greater and Lesser Caucasus mountains. Larvae of L. hennigrata killed on average 57–117 eggs in 24 h, depending on their size, the number of eggs offered to them, and possibly some environmental factors. In no-choice tests, adult flies oviposited on twigs containing different non-target adelgid, aphid, and scale insect species. Larvae of L. hennigrata were observed to feed on several of them. However, only the non-target species Mindarus abietinus Koch supported development of a single specimen to the adult stage. During field surveys in Switzerland and Georgia, L. hennigrata was never found on any sampled non-target species. Based on our findings, we conclude that L. hennigrata is a suitable classical biological control agent because it (1) is already present in countries that neighbor northern Europe, (2) is a dominant natural enemy of the pest in Switzerland, (3) is an efficient predator of the pest's eggs, and (4) seems to be specific to Ad. nordmannianae in its ecological range. [ABSTRACT FROM AUTHOR]