Oligophagous Species Research Articles

Legume (Fabaceae) and seed beetle (Coleoptera, Chrysomelidae, Bruchinae) species of Europe: distribution and host specialization

The paper investigates the distributions of legumes (Fabaceae) and their associated seed beetle species (Bruchinae) across vegetation zones and regions of Europe and evaluates the host range and specialization of seed beetles. 1584 legume species/subspecies/varieties were included in the study and ca. 16% of these serve as known hosts by the 175 seed beetle species found in Europe. Both plant and seed beetle species richness increased from the Boreal to Mediterranean zones/regions. 717 legume species occurred only in single zones/regions and only 4.7% of these (34 species) were hosts for 38 bruchine species specific to a zone/region. Europe has 664 native legume species and 381 of these are Eu-endemics. There were 52 alien legume species found. Similarities in plant species composition by the Sørensen index were pronounced between the Central-European and the Mediterranean, between the Transcaucasian and Mediterranean, and between the Colchis-Caucasian and the Pontic-Caspian areas. The most species-rich genus is Astragalus L. with 334 species and 16 subspecies. Of the two major pre-dispersal seed predator genera, Bruchidius Schilsky species are sensu lato oligophagous, using a wide range of leguminous tribes as hosts, but restricted to few host species within a tribe. In contrast, members of the Bruchus L. genus are sensu stricto oligophagous species and, despite being constrained to the Fabeae tribe, most of them feed on several Lathyrus L. and Vicia L. species. The ways annual and perennial life cycles as well as chemical constituents of legumes might affect the colonization success of the seed beetles are discussed.

Visual and chemical cues in the host plant selection of the melon ladybird Chnootriba elaterii (Coleoptera: Coccinellidae)

Phytophagous insects employ various sensory cues in the host plant location such as visual, olfactory, gustatory, and tactile stimuli, which are perceived by sensory systems and integrated in higher brain centres to trigger the correct behavioural responses. In the present study, the host location process of the oligophagous species Chnootriba elaterii (melon ladybird) is investigated in controlled conditions using both a Y-Tube olfactometer and an open Y-Track olfactometer. Olfactory and visual cues from the host plant act synergistically to lead the ladybirds towards the host plant. Females of C. elaterii are not able to discriminate between host and non-host plants using either olfactory or visual cues alone. Visual cues, particularly those associated with the colour green, are of higher relative importance compared to olfactory cues in the host location process. Green dummy plants made of cardboard represent strong supernormal stimuli for C. elaterii females. The results of the present study can shed light on the host location process of Coccinellidae and can help to develop visual or chemical traps which can be useful in monitoring and controlling this important crop pest of the Mediterranean Basin.

Ecological and life‐history traits predict temporal trends in biomass of boreal moths

Abstract Dramatic insect declines, and their consequences for ecosystems globally, have received considerable attention recently. Yet, it is still poorly known if ecological and life‐history traits can explain declines and whether insect decline occurs also at high latitudes. Insects' diversity and abundance are dramatically lower at high latitudes compared to the tropics, and insects might benefit from climate warming in high‐latitude environments. We adopted a trait‐ and biomass‐based approach to estimate temporal change between 1993 and 2019 in Finnish macro‐moth communities by using data from 85 long‐running light traps. We analysed spatio‐temporal variation in biomass of moth functional groups with Joint Dynamic Species Distribution Models while accounting for environmental variables. We did not detect any declining trends in total moth biomass of moth functional groups, and most groups were stable over time. Moreover, biomass increased for species using coniferous trees, lichens, or mushrooms as hosts, multivoltine species, as well as monophagous and oligophagous species feeding on trees. We found that length and temperature of the growing season, winter climatic conditions, and habitat structure all partially explained variation in moth biomass. Although boreal moth communities are rapidly changing due to species turnover, in terms of total biomass they seem to contradict the trend of dramatic insect declines observed globally. This may lessen the immediate possibility of negative bottom‐up trophic cascades in boreal food webs.

Risk assessment of Resseliella citrifrugis for the EU.

Following a request from the European Commission, the EFSA Panel on Plant Health performed a risk assessment of the citrus fruit midge Resseliella citrifrugis (Diptera: Cecidomyiidae), an oligophagous species, which feeds on fruits of Citrus spp., and is reported from China. The pest was temporarily regulated in October 2022 (Regulation (EU) 2022/1941, under Art. 30 (2016/2031)). The entry risk assessment focused on the citrus fruit pathway. Three scenarios were considered: A0 (current practice, i.e. regulated pest for the EU), A1 (deregulation) and A2 (A0 with additional stand-alone post-harvest cold treatment). Based on the outputs of the entry model, under scenario A0, slightly less than 40 potential founder populations per year are expected (median; 90%-uncertainty interval between about one per 30 years and about 3,000 per year). Under scenario A1, the risk of entry increases by about three times and reaches about 120 potential founder populations per year (median; 90%-uncertainty interval between about one per 10 years and about 9,000 per year). Compared to scenario A0, the risk of entry is orders of magnitude lower for scenario A2 (median = about one potential founder population per 120 years; 90%-uncertainty interval between one per about 600 million years and about two per year). The main uncertainties in the entry assessment are the probability of transfer, the RRO effectiveness (for scenario A2) and the disaggregation of consignments (transport of citrus fruit in boxes or lots to different locations). For all scenarios, the number of established populations is only slightly lower than the number of potential founder populations. Establishment is thus not expected to be a major constraint for this pest to then spread and cause impacts, despite the uncertainty about the pest thermal requirements. The median lag period between establishment and spread is estimated to be about 18 months (90%-uncertainty interval between about 7 and 54 months). After the lag period, the median rate of spread by flying and due to transport of harvested citrus fruit from orchards to packinghouses is estimated at about 100 km/year (90%-range between about 40 and 500 km/year). The main uncertainties in the spread assessment include the level of susceptibility of cultivars of different citrus species in the EU, the spread rate in China and the climate suitability of the initial spread focus in the EU. The median impact of R. citrifrugis in the EU citrus-growing area (proportion of infested citrus fruit out of harvested citrus fruit) is estimated at about 10% (90%-uncertainty interval between about 2% and 25%). Uncertainties affecting the impact assessment include the susceptibility of different citrus cultivars and the effect of the citrus fruit-harvesting season in the EU (mainly winter, the less suitable season for the pest).

Population development of Acanthiophilus helianthi (Rossi) (Diptera: Tephritidae) On Five Different Safflower Varieties in Van, Turkey

Acanthiophilus helianthi (Rossi, 1794) (Diptera: Tephritidae) also known as safflower fly, is an oligophagous species that cause significant damage to safflower plants. Safflower Carthamus tinctorius (L.) (Asterales: Asteraceae) plant, which is among its hosts, is an important energy plant whose cultivation has increased in recent years in our country resistant to drought and has high adaptability. This study investigated the population growth of A. helianthi on different safflower varieties (Asol, Ayaz, Balcı, Dinçer and Göktürk) in Van Yuzuncu Yıl University, Faculty of Agriculture for two years (2019-2020) in Van province. Result of the study, it was determined that the pest showed a similar population change in both years, the adult individuals were seen at the end of June - mid-August, and their pupae from this date to the beginning of September. It was seen that the insect density was statistically different between the varieties at different sampling dates and the highest adult density was found in Asol pupae in both years, and in Göktürk variety. It was determined that Ormyrus sp. (Hymenoptera: Ormyridae), Microdontomerus annulatus (Spinola, 1808) (Hymenoptera: Torymidae), Eurytoma acroptilae (Zerova, 1986) (Hymenoptera: Eurytomidae) and Bracon sp. (Hymenoptera: Braconidae) are essential parasitoids of A. helianthi and show different densities on varieties. It has been observed that thorn, color, vegetative development, climatic factors, and parasitoids play an active role in the population development of safflower cultivars.

A chromosome-level genome assembly of the beet armyworm Spodoptera exigua

BackgroundThe beet armyworm Spodoptera exigua is a polyphagous caterpillar that causes serious damage to many species of crops and vegetables. To gain insight into how this polyphagous insect differs from less harmful oligophagous species, we generated a chromosome-level assembly and compared it to closely related species with the same or different feeding habits. ResultsBased on Illumina and Pacific Biosciences data and Hi-C technology, 425.6 Mb of genome sequences were anchored and oriented into 31 linkage groups, with an N50 length of 14.8 Mb. A total of 24,649 gene models were predicted, of which 97.4% were identified in the genome assembly. Chemosensory genes are vital for locating food: of the four main families, odorant-binding proteins, chemosensory proteins and olfactory receptors showed little difference, whereas gustatory receptors are greatly expanded in S. exigua. Examination of other polyphagous insects confirmed this difference from oligophagous congeners and further identified the bitter receptor subfamily as being particularly affected. ConclusionOur high-quality genome sequence for beet armyworm identified a key expansion of the bitter gustatory receptor subfamily in this and other pests that differs crucially from more benign relatives and offers insight into the biology and possible future means of control for these economically important insects.

Distribution of Phloeosinus tacubayae Hopkins, 1905 (Curculionidae, Scolytinae), the Cypress Bark Beetle, and new records from potential distribution models

We evaluated the biotic and abiotic conditions related to the presence of Phloeosinus tacubayae Hopkins, 1905, to update its distribution and explore new areas to collect the species from potential distribution models and establish its host range. Our results support that P. tacubayae is an oligophagous species distributed mostly in five provinces from the Mexican Transition Zone; its distribution pattern belongs to the Nearctic cenocron and is related to the distribution pattern of its principal host. The modeling and distribution of its hosts suggest invadable zones where new records may exist.

Primer registro de Eupteryx decemnotata (Cicadellidae: Typhlocybinae) en la Argentina

Eupteryx decemnotata (Rey) is an oligophagous species of potential economic importance. It is native to Mediterranean region. Then, it spread throughout most of Europe and reached North America. In this work it is recorded for the first time in Argentina. Distinctive characters of the species are mentioned and illustrated.

Trophic relationships and mining seasons of the Nepticulidae of Lithuania: an updated survey

This study provides updated summarised data on host-plant preferences and mining seasons of the Nepticulidae of the Lithuanian fauna. It revealed that the Lithuanian Nepticulidae are trophically associated with 34 genera and 14 families of host plants. Four of these host-plant families stand out in a number of mining Nepticulidae species and all together host about 80% of the Lithuanian Nepticulidae. As regards feeding specialisation, the fauna of the Lithuanian Nepticulidae consists of three constituents: monophagous species (about 44%), narrow oligophagous species (about 48%), and true oligophagous species (about 8%). There are two distinctive peaks of mining: the summer peak from mid-June until mid-July and the autumn peak from early September until mid-October, when most species mine simultaneously.

АДАПТАЦИИ ВИДА К ОБИТАНИЮ НА ПЕРИФЕРИИ АРЕАЛА: ОБЗОР ОСОБЕННОСТЕЙ БИОЛОГИИ ПОЛЧКА (GLIS GLIS LINNAEUS, 1766) В САМОЙ ВОСТОЧНОЙ ПОПУЛЯЦИИ

Marked peculiarities in the biology of a species that may be observed, possibly regardless of genetic changes, on the periphery of the species habitat may provide for species survival under extreme conditions. The same may be relevant to populations that are isolated, marginal, or remote from the main distribution range of a species. With this in mind, several biological features of the edible dormouse were studied. This rodent species features a vast distribution range in Europe and partly in Asia. Differentiation into subspecies is mostly not observed within the range. This allows comparing the biology of a single species over significantly distant areas. The range of biotope preferences of the dormice on the periphery of their distribution is wider than in the central areas. In the former cases, these rodents were found in forests featuring a significant proportion of birch and aspen in the forest stand. These observations are similar to those on the northern boundary of the dormouse distribution range in Poland and Lithuania. Some specific features of the diet of the species are associated with these habitats. In the Zhiguli Mts. (Russia) and Lithuania, the main diet includes birch seeds. At the same time, fruits and berries, which are of major importance in the other parts of dormice distribution range, are completely absent among the juicy forages. These differences probably underlie the development of a unique mechanism of reproduction control, which is not observed in other mammalian species. On the periphery of the distribution range, the number of sources of the basic forages for the highly specialized species under study is increased compared to the rest of the distribution area, and the reproductive activity of dormice is annual. However, upon the absence of a sufficient amount of the high-calorie food, mass embryonic resorption in most of females occurs. In addition, in the easternmost population, a higher territoriality is featured by females rearing offspring, and the phenomenon of communal nesting by related females is not observed. To confirm whether the genetic or environmental factors are at the base of the biological features described, large-scale population genetic studies are warranted. At the present stage, field studies allow tracing analogous features in other parts of the species habitat and thus help illustrating the ecological plasticity of the oligophagous species under suboptimal conditions.

Phylogenetic Position of a New Trisetacus Mite Species (Nalepellidae) Destroying Seeds of North American Junipers and New Hypotheses on Basal Divergence of Eriophyoidea.

Simple SummaryEriophyoid mites are microscopic herbivores associated with higher plants. Some of them are serious pests due to their ability to vector viruses and cause other damage to host plants. Mites of the genus Trisetacus are widespread parasites of conifers. They usually live in buds, cones, and rarely within needles of Pinaceae (pine family) and Cupressaceae (cypress family). We discovered a new species, Trisetacus indelis n. sp., severely damaging seeds of three North American junipers in the western USA. This species possesses two morphologically different forms of females and has two deletion mutations in the gene cytochrome oxidase subunit I (Cox1). Such mutations are rare in eriophyoids and were previously detected only in two pestiferous species from palms and hazelnut. Our molecular-phylogenetic analyses determine the closest known relatives of the new species and suggest that Old and New World Trisetacus independently transitioned to living in seeds of junipers. Additionally we show that reconstruction of the phylogeny of Eriophyoidea based on one gene, Cox1, produces a poorly-resolved but biologically consistent tree topology to hypothesize the evolution of Eriophyoidea. Overall, our study improves our understanding of the diversity of conifer-inhabiting mites and indicates further needs in investigating the phylogeny of Eriophyoidea.Eriophyoid mites of the genus Trisetacus Keifer are widespread parasites of conifers. A new oligophagous species, T. indelis n. sp., was discovered severely damaging seeds of North American junipers (Juniperus osteosperma, J. occidentalis, and J. californica) in the western USA. It has two codon deletions in the mitochondrial gene Cox1 rarely detected in Eriophyoidea and includes distinct morphological dimorphism of females. A phylogenetic analysis based on amino acid alignment of translated Cox1 sequences using a large set of out-groups (a) determined that two North American congeners, T. batonrougei and T. neoquadrisetus, were the closest known relatives of T. indelis n. sp., and (b) indicated that Old and New World seed-inhabiting Trisetacus from junipers do not form a distinct clade, suggesting a possible independent transition to living in seeds of junipers in America and Eurasia by Trisetacus spp. Our analysis produced a new topology consistent with a scenario assuming gradual reduction of prodorsal shield setation in Eriophyoidea and an ancient switch from gymnosperms to other hosts. Additionally, our analysis did not support monophyly of Trisetacus; recovered a new host-specific, moderately supported clade comprising Trisetacus and Nalepellinae (Nalepella + Setoptus) associated with Pinaceae; and questioned the monophyly of Trisetacus associated with Cupressaceae.

Strong impact of temperature and resource specialisation on patterns of voltinism within an oak‐associated insect community

Abstract Insect phenology consists of the timing of life events, as well as the number of generations (voltinism). While several studies have focused on the impact of climate on the timing of seasonal events, or the voltinism of single species, we have few insights into the factors that shape patterns of voltinism within ecological communities. Importantly, voltinism can have a major impact on population growth, species interactions, and rate of evolution. We investigated the relative importance of spatial variation in temperature and species traits in shaping patterns of voltinism within an herbivore community feeding on deciduous oaks across a temperature gradient in Europe. Voltinism increased with temperature, where the probability for a species to be univoltine decreased with temperature, whereas the probability for a species to be strictly multivoltine increased with temperature. The relative abundance of the first and subsequent generations of multivoltine species did not significantly change along the temperature gradient. Resource specialisation affected voltinism, where oligophagous and polyphagous species were more likely to be strictly multivoltine than narrow oligophagous species. Overwintering stage and body size did not affect voltinism, and there was no evidence that species traits influenced the relationship between temperature and voltinism. Our findings highlight that temperature and species traits shape variation in voltinism within an herbivore community associated with oak trees. These temperature‐induced shifts in voltinism within the oak‐associated herbivore community may have profound effects on the synchrony within and between trophic levels, and consequently for food web structure and outbreak dynamics.

Discovery of the new Coptotriche species in China revealed two novel host-plant families and host-plant orders for Tischeriidae, a family of stenophagous, leaf-mining lepidopterans.

The article describes three new species of Coptotriche Walsingham, 1890 from China and adjacent northern Vietnam: C. camptotheca Xu Dai, sp. nov. feeding on Camptotheca acuminata Decne. (Nyssaceae); C. turpinia Xu Dai, sp. nov. feeding on Turpinia arguta (Lindl.) Seem. (Staphyleaceae); and C. asiana Dikus Stonis, sp. nov. The latter appeared to be a narrow oligophagous species feeding on various Symplocos Jacq.: S. sumuntia Buch.-Ham. ex D. Don, S. poilanei Guill., and Symplocos glauca (Thunb.) Koidz. (Symplocaceae). Nyssaceae and Staphyleaceae are novel host-plant families of Tischeriidae. The new species are illustrated with photographs of adults, male and female genitalia, and leaf mines. The article also briefly discusses about the proportion of monophagous and oligophagous species of Tischeriidae.

Host specialization, genetic variability, and differentiation in three species of Tomoplagia from Brazilian rupestrian grasslands

AbstractIn this study, the geographic and host plant‐associated genetic structure of Tomoplagia spp. (Diptera: Tephritidae) was investigated. The study was developed in the rupestrian montane grasslands of the Espinhaço Mountain Range, Brazil, where these flies’ larvae develop within flower heads of Asteraceae. The three species of Tomoplagia investigated have different host spans within the subtribe Vernoniinae: one is strictly monophagous (Tomoplagia grandis Prado, Norrbom & Lewinsohn) and two are oligophagous [Tomoplagia incompleta (Williston) and Tomoplagia bicolor Prado, Norrbom & Lewinsohn]. The genetic variability and differentiation throughout their geographic distribution were investigated at the local scale (sympatric, between different host species in the same locality) and the regional scale (allopatric, on the same or different host species in different localities). Allele richness was greater for populations of the two oligophagous species. Moreover, population genetic structure was low in all species both on the local and regional scales, and the attribution of individuals of the three species to different genetic groups was not strongly associated with either locality or host plant. These results indicate the absence of simple geographic and host‐associated genetic structure in these specialized herbivores, suggesting that females of T. bicolor and T. incompleta have low host philopatry, using various host species indiscriminately within their distribution range. Therefore, the use of host plants by fruit flies of the genus Tomoplagia is a plastic character that can shift temporally and spatially among phylogenetically related and chemically similar plants. Contrary to expectations, given the specialized and intimate nature of their host association, the studied Tomoplagia species showed no clear host‐associated genetic differentiation; instead, genetic variation presents a mosaic pattern across hosts and localities.

Pest categorisation of Leucinodes pseudorbonalis.

The EFSA Panel on Plant Health performed a pest categorisation of the snout moth Leucinodes pseudorbonalis Mally, Korycinska, Agassiz, Hall, Hodgetts & Nuss (Lepidoptera: Crambidae), for the territory of the EU. This species is not included in the EU Commission Implementing Regulation 2019/2072. This oligophagous species, which feeds on fruit and leaves of Solanum aethiopicum (Ethiopian eggplant) and S. melongena (eggplant), is known to occur in sub‐Saharan Africa (Angola, Liberia, Senegal, Uganda). Adults oviposit on leaves and newly hatched caterpillars can bore into shoots, causing wilting and dieback, before moving into the fruit, which they tunnel. Damage may be visible only if the fruit is cut open. A single aubergine can be infested by up to 20 larvae. Mature larvae abandon the fruit to pupate in a cocoon in the soil. Adult moths fly for short distances only in darkness. Potential entry pathways for L. pseudorbonalis, such as Solanum spp. plants for planting and soil/growing media are regulated and can be considered as closed. The fruit and leaves pathways remain open from countries where L. pseudorbonalis is known to occur. Indeed, this species was intercepted in the EU with S. aethiopicum eight times from January to June 2021. Should L. pseudorbonalis enter the EU, host availability (S. melongena) and climatic conditions in some limited areas of southern EU Member States could allow this species to successfully establish and spread within these areas. Economic impact in aubergine production is anticipated if establishment occurs. L. pseudorbonalis satisfies the criteria that are within the remit of EFSA to assess for this species to be regarded as a potential Union quarantine pest. Because this is a recently described species, there are knowledge gaps related to the biology of this moth and its distribution. However, these gaps do not affect the conclusions of this categorisation.

The genome of the black cutworm Agrotis ipsilon

The black cutworm (BCW), Agrotis ipsilon, is a worldwide polyphagous and underground pest that causes a high level of economic loss to a wide range of crops through the damage of roots. This species performs non-directed migration throughout East and Southeast Asia seasonally. Lack of a genome information has limited further studies on its unique biology and the development of novel management approaches. In this study, we present a 476 Mb de novo assembly of BCW, along with a consensus gene set of 14,801 protein-coding gene models. Quality controls show that both genome assembly and annotations are high-quality and mostly complete. We focus manual annotation and comparative genomics on gene families that related to the unique attributes of this species, such as nocturnality, long-distance migration, and host adaptation. We find that the BCW genome encodes a similar gene repertoire in various migration-related gene families to the diural migratory butterfly Danaus plexiipus, with additional copies of long wavelength opsin and two eye development-related genes. On the other hand, we find that the genomes of BCW and many other polyphagous lepidopterans encode many more gustatory receptor genes, particularly the lineage-specific expanded bitter receptor genes, than the mono- or oligo-phagous species, suggesting a common role of gustatory receptors (GRs) expansion in host range expansion. The availability of a BCW genome provides valuable resources to study the molecular mechanisms of non-directed migration in lepidopteran pests and to develop novel strategies to control migratory nocturnal pests.

Impact of host and plant phylogenies on parasitoid host range

Host specificity of parasitoids is a key trait reflecting their functional role in ecosystems. It is thought to be shaped by phylogenetic relationships among potential host species and those plants bearing the hosts. However, the respective importance of these phylogenetic signals in the host range of the parasitoid has been scarcely described. In this context, we evaluated the effect of phylogenetic (and taxonomic) signals of plants and host species on parasitoid host range (assessing parasitoid ability to produce offspring) in three aphid parasitoids (Aphelinus abdominalis, Aphidius ervi and A. rhopalosiphi) exposed to 16 plant-aphid complexes encompassing their ecological host range. The parasitoids were all categorized as oligophagous species and a phylogenic signal was detected in plant and aphid species phylogenies for A. rhopalosiphi and A. abdominalis host ranges, respectively. Aphelinus abdominalis specialized on aphids belonging to the Dactynotine subtribe and A. rhopalosiphi on species feeding on Poaceae. By contrast, no cluster was detected in the host range of A. ervi. Similar results were found when considering taxonomic signals, suggesting that taxonomic data are equally useful for assessing parasitoid host specificity. Identifying phylogenetic (or taxonomic) signals that dictate parasitoid host specificity could be useful for detecting non-target species at risk in the framework of classical biological control programs and targeting pest species in the context of such programs.

Pest categorisation of Resseliella citrifrugis.

The EFSA Panel on Plant Health performed a pest categorisation of the citrus fruit midge, Resseliella citrifrugis Jiang (Diptera: Cecidomyiidae), for the territory of the EU. This species is not included in EU Commission Implementing Regulation 2019/2072. This oligophagous species, which feeds on Citrus spp. fruits, is known to occur in China (provinces of Fujian, Gansu, Guangdong, Guangxi, Guizhou, Hubei, Hunan, Jiangxi and Sichuan). First‐generation adults emerge in April and oviposit on the peduncle and calyx of citrus fruits. Larvae feed on the albedo (the white layer between skin and pulp) of the fruit, which they tunnel. Infested fruit most often drop prematurely. Larvae pupate either within the fallen fruit or in the soil. This species has three main peaks of activity (May, June–July, August–September) and four generations per year in its native range. Mature larvae from the last generation are the overwintering stage. Potential entry pathways for R. citrifrugis, such as Citrus spp. plants for planting with foliage and soil/growing media, and soil/growing media can be considered as closed. The citrus fruit pathway remains open from countries where R. citrifrugis is known to occur. Indeed, this species was intercepted in fresh pomelos 11 times from December 2020 to January 2021 in the EU. Should R. citrifrugis enter the EU, the ample availability of hosts (Citrus spp.) and the climatic conditions in citrus‐growing areas of southern EU Member States would most probably allow this species to successfully establish and spread. Economic impact in citrus production is anticipated if establishment occurs. R. citrifrugis satisfies the criteria that are within the remit of EFSA to assess for this species to be regarded as a potential Union quarantine pest. There is uncertainty about the nomenclature of R. citrifrugis and its exact host range. However, because the name Resseliella citrifrugis is used in multiple sources reporting it as a pest of citrus in China, where symptoms, biology and impact are described, these uncertainties do not affect the conclusions of this categorisation.

Pest categorisation of Citripestis sagittiferella.

The EFSA Panel on Plant Health performed a pest categorisation of the citrus pulp borer, Citripestis sagittiferella (Lepidoptera: Pyralidae), for the EU. This oligophagous species, which feeds on Citrus spp., occurs in Southeast Asia, mostly in lowlands but can also be found up to 1,200 m above sea level. Adults oviposit on citrus fruit at any stage of the fruit development. Larvae feed in the fruit then abandon it to pupate in the soil within an earthen cocoon. C. sagittiferella is multivoltine in its native range. This species is not included in EU Commission Implementing Regulation 2019/2072. Potential entry pathways for C. sagittiferella, such as Citrus spp. plants for planting with foliage and soil/growing medium, and soil/growing medium by themselves can be considered as closed. The citrus fruit pathway remains open for countries where C. sagittiferella is known to occur. Indeed, this species was intercepted several times in the UK during the last decade. Hosts of C. sagittiferella are available (Citrus spp.) in the southern EU. The EU has climatic conditions that are also found in countries where C. sagittiferella occurs although it is unknown whether C. sagittiferella occurs in those areas. Economic impact in citrus production is anticipated if establishment and spread occur. C. sagittiferella satisfies the criteria that are within the remit of EFSA to assess for this species to be regarded as a potential Union quarantine pest. There is uncertainty about the climatic requirements of this species, which may hamper its establishment in the EU.

Species traits affect phenological responses to climate change in a butterfly community

Diverse taxa have undergone phenological shifts in response to anthropogenic climate change. While such shifts generally follow predicted patterns, they are not uniform, and interspecific variation may have important ecological consequences. We evaluated relationships among species’ phenological shifts (mean flight date, duration of flight period), ecological traits (larval trophic specialization, larval diet composition, voltinism), and population trends in a butterfly community in Pennsylvania, USA, where the summer growing season has become warmer, wetter, and longer. Data were collected over 7–19 years from 18 species or species groups, including the extremely rare eastern regal fritillary Speyeria idalia idalia. Both the direction and magnitude of phenological change over time was linked to species traits. Polyphagous species advanced and prolonged the duration of their flight period while oligophagous species delayed and shortened theirs. Herb feeders advanced their flight periods while woody feeders delayed theirs. Multivoltine species consistently prolonged flight periods in response to warmer temperatures, while univoltine species were less consistent. Butterflies that shifted to longer flight durations, and those that had polyphagous diets and multivoltine reproductive strategies tended to decline in population. Our results suggest species’ traits shape butterfly phenological responses to climate change, and are linked to important community impacts.