Climate and land use change can alter the incidence and strength of biotic interactions, with important effects on the distribution, abundance and function of species. To assess the importance of these effects and their dynamics, studies quantifying how biotic interactions change in space and time are needed. We studied interactions between nettle-feeding butterflies and their shared natural enemies (parasitoids) locally and across 500 km latitudinal gradient in Sweden. We also examined the potential impact of the range-expansion of the butterfly Araschnia levana on resident butterflies via shared parasitoids, by studying how parasitism in resident butterflies covaries with the presence or absence of the newly-established species. We collected 6777 larvae of four nettle-feeding butterfly species (Aglais urticae, Aglais io, Ar. levana and Vanessa atalanta), over two years, at 19 sites distributed along the gradient. We documented the parasitoid complex for each butterfly species and measured their overlap, and analysed how parasitism rates were affected by butterfly species assemblage, variations in abundance, time, and the arrival of Ar. levana. Parasitoids caused high mortality, with substantial overlap in the complex of parasitoids associated with the four host butterflies. Levels of parasitism differed significantly among butterflies and were influenced by the local butterfly species assemblage. Our results also suggest that parasitism in resident butterflies is elevated at sites where Ar. levana has been established for a longer period. In our study system, variations in butterfly species assemblages were associated in a predictable way with substantial variations in rates of parasitism. This relationship is likely to affect the dynamics of the butterfly host species, and potentially cascade to the larger number of species with which they interact. These results highlight the importance of indirect interactions and their potential to reorganise ecological communities, especially in the context of shifts in species distributions in a warmer world.

Burnet moths (Zygaena spp.) are day-flying Lepidoptera considered indicative of species-rich grasslands. In the present study, our aim was to clarify whether clear-cuts are habitat, supporting habitat or matrix for three species of Zygaena. We did so by sampling these species with sex pheromones on 48 clear-cuts, varying in amount of host and nectar plants, in southern Sweden. To compare the efficiency of such sampling, we also conducted transect walks on these clearcuts. Overall, host-plants on clear-cuts best explained the abundance of Zygaena spp. recorded, better than nectar-plants or connectivity with nearby grasslands. These results indicate that clear-cuts with an abundance of host plants are used as a fully functional habitat, and not a supporting habitat in the sense of only providing nectar. There is no support in these results for considering clear-cuts as an inert matrix. With about half the work-effort, pheromone traps recorded 100 times more Zygaena spp. as transect walks. The poor correspondence between observations during transects walks and pheromone trap catches suggest Zygaena spp. being difficult to monitor by transect walks. In contrast to grasslands, clear-cuts are short-term in nature requiring repeated recolonization, indicating the importance of permanent grasslands. However, clear-cuts are important temporary insect habitats due to their great acreage, and suitable management can increase the time they remain a habitat.

Recent global change has had a substantial influence on the distribution of organisms, and many species are currently expanding their ranges. To evaluate the underlying processes, long-term data with good geographic resolution are essential. One important but generally overlooked data source is offered by the taxon-specific national catalogues of first provincial records that are kept in many countries. Here, we use such data to quantify trait-based influences on range expansion in Swedish butterflies and moths between 1973 and 2010. Of 282 species meeting pre-defined quality criteria, 170 expanded their northern range margin, with a mean expansion rate of 2.7 km per year. The analyses demonstrate that habitat and diet generalists, forest species and species active during warm conditions have expanded their ranges more rapidly than other species. Notably, range expansion in diet specialists was positively related to a nitrogen-favoured larval diet, an effect not found among oligo- or polyphagous species. In contrast to the general view, this shows that specialist species can undergo rapid range expansion. We suggest that increased areas of nitrogen-rich habitat, and increased availability of a nitrogen-favoured diet, are among the most important drivers of range expansions, potentially having far-reaching consequences for a wide variety of organisms.

I denna nya fältguide till svenska dagfjärilar beskrivs drygt 180 arter, underarter, former och tillfälliga besökare. Boken är rikt illustrerad och fjärilarna åtföljs av fotografier på hane, hona och undersida jämte grafiska bilder över utbredningar och flygtider. Boken är den tredje i Naturcentrums serie om växter och djur i Sverige. Tidigare har "Lavar - en fältguide" och "Mossor en fältguide" utgivits.

Ett kort inledande avsnitt beskriver bokens tillkomst, hur den är uppbyggd, terminologi, litteratur samt lite om fjärilsskådning. Därefter följer bokens huvuddel som utgörs av artbeskrivningarna och ca 1.000 illustrationer ledsagar läsaren. Boken, som omfattar 200 sidor, är framtagen av Sven Birkedal, naturälskare och fotograf från Åhus. Fjärilsforskaren Nils Ryrholm har stått för kompletterade texter och beskrivningar, vetenskaplig granskning, utbredningskartor, flygtider, m. m.

Synanthedonvespiformis L. (Lepidoptera: Sesiidae) is considered a rare insect in Sweden, discovered in 1860, with only a few observations recorded until a sex pheromone attractant became available recently. This study details a national survey conducted using pheromones as a sampling method for this species. Through pheromone trapping we captured 439 specimens in Southern Sweden at 77 sites, almost tripling the number of previously reported records for this species. The results suggest that S. vespiformis is truly a rare species with a genuinely scattered distribution, but can be locally abundant. Habitat analyses were conducted in order to test the relationship between habitat quality and the number of individuals caught. In Sweden, S. vespiformis is thought to be associated with oak hosts, but our attempts to predict its occurrence by the abundance of oaks yielded no significant relationships. We therefore suggest that sampling bias and limited knowledge on distribution may have led to the assumption that this species is primarily reliant on oaks in the northern part of its range, whereas it may in fact be polyphagous, similar to S. vespiformis found as an agricultural pest in Central and Southern Europe. We conclude that pheromones can massively enhance sampling potential for this and other rare lepidopteran species. Large-scale pheromone-based surveys provide a snapshot of true presences and absences across a considerable part of a species national distribution range, and thus for the first time provide a viable means of systematically assessing changes in distribution over time with high spatiotemporal resolution.

In this study, we examined the evolutionary outcome of and interplay between historic isolation and current selection pressures on traits more or less closely connected to fitness in the Pearly Heath butterfly (Coenonympha arcania) across its range in Europe. We hypothesized that a trait mean is more related to historic events if it has low connection to fitness, while a trait more closely connected with fitness is expected to have a mean that relates more to current selection pressures. In order to test this, we collected 322 butterflies from across the species range in Europe and measured five wing traits relating to size and color patterns. To infer a phylogeographic history for each individual, we sequenced a 594 bp fragment of the COI gene. The morphological data were then analyzed in relation to selected climatic variables and the history of individuals to disentangle which factors best correlated with morphological variation. The results supported our hypothesis in that wing sizes correlated with summer precipitation but not with its inferred location during the last glaciation. Eyespot position, on the other hand, correlated with the history of individuals but not with the analyzed climatic indicators. The sizes of the black spot and the white band, two traits that were expected to have intermediate selection pressure, were associated with both history and current conditions. Thus, this study illustrates the fascinating interplay between events and processes that lead to a specific evolutionary outcome.

Populations at range margins may be genetically different from more central ones for a number of mutually non-exclusive reasons. Specific selection pressures may operate in environments that are more marginal for the species. Genetic drift may also have a strong effect in these populations if they are small, isolated and/or have experienced significant bottlenecks during the colonisation phase. The question if peripheral populations are special, and if yes then how and why, is of obvious relevance for speciation theory, as well as for conservation biology. To evaluate the uniqueness of populations at range margins and the influence of gene flow and selection, we performed a morphometric study of two grassland butterfly species: from Swedish populations that are peripheral and isolated from the main area of the species distributions and from populations in the Baltic states that are peripheral but connected to the main area of the species distributions. These samples were compared to those from central parts of the species distributions. The isolated populations in both species differed consistently from both peripheral and central populations in their wing size and shape. We interpret this as a result of selection caused by differences in population structure in these isolated locations, presumably favoring different dispersal propensity of these butterflies. Alternative explanations based on colonisation history, latitudinal effects, inbreeding or phenotypic plasticity appear less plausible. As a contrast, the much weaker and seemingly random amongregion differences in wing patterns are more likely to be ascribed to weaker selection pressures allowing genetic drift to be influential. In conclusion, both morphological data and results from neutral genetic markers in earlier studies of the same system provide congruent evidence of both adaptation and genetic drift in the isolated Swedish populations of both species.

Depending on their faunal content islands can function as important ‘vehicles’ for conservation. In this study, we examine data on 440 butterfly species over 564 European islands in 10 island groups. To determine the status of the butterfly fauna, we have adopted two approaches, island-focused and species-focused, examined using principal components analysis and regression modelling.

In the former, we relate species richness, rarity and endemicity to island geography (area, elevation, isolation and location in latitude and longitude); in the latter, species occurrence on islands is examined in relation to distribution, range, range boundaries, and altitudinal limits on the continent as well as species’ ecology (number of"/> host plants) and morphology (wing expanse). Species on islands are also assessed for their status on the continental mainland, their distributional dynamics (extinctions, distribution changes) and conservation status (Red Data Book, European Habitat Directive, Species of European Conservation Concern and Bern Convention listing.

Unexpectedly, we find that a large fraction of the European butterfly species is found on the islands (63.4%; 59% on small islands) comprising some 6.2% of the land area of Europe. Although species occurring on the islands tend, on the whole, to have lower conservation status and are not declining over Europe, 45 species are endemics restricted to the islands. Species richness shows only a weak locational pattern and is related as expected to isolation from the continental source and island area; but, both rarity and endemicity have distinctive geographical bias to southern Europe, on islands now under increasing pressure from climate change and increasingly intensive human exploitation. The vulnerability of species on islands is emphasised in the relationship of island occurrence (% occurrence and presence/absence of species on any island) with continental distributions. A large proportion of the variation (84%) is accounted by continental distribution, the southern range limit and lower altitudinal limit. Most species (69%) occur on very few islands (\5%). In view of ongoing species dynamics on islands, migrations and extinctions of species, island repositories of species depend in large part on conservation of butterflies at continental sources. The unique faunas and rare species on islands also depend on appropriate concern being given to the island faunas. Conservation of European islands is thus a two-way process, sustaining sources and conserving island refuges. Residuals from the regressions (islands with more or fewer species, rare and endemic species; species occurring more or less frequently than expected on islands) provide warning signals of regions and islands deserving immediate attention.

In recent years, there has been an increasing amount of literature on various approaches to the study of pheromone systems in Insecta. Much of the current research on attractive molecules pays particular attention to their chemical structure, isomerism and biosynthesis (Efetov et al., 2010, 2011, 2015, 2016; Efetov & Gorbunov, 2016; Subchev et al., 2010, 2012, 2013). The synthetic sex attractants EFETOV-2 and EFETOV-S-2 created in the Crimean Federal University (Efetov et al., 2014) were tested in Sweden in 2016 and 2017. Cardboard strips containing rubber caps with the baits were hung on plants at a height of 0.5–1.0 m above the ground. A specimen was considered attracted if a male landed on the strip or flew up and touched it. The field trials were conducted in three localities: northern Gästrikland in the village Rönnåsen, 60 km NW of Gävle (eastern central Sweden); Hörröd, Skåne County (south Sweden) and Ravlunda, Skåne County (south Sweden). It was shown that EFETOV-2 and EFETOV-S-2 were attractive for the males of Adscita (Adscita) statices statices (Linnaeus, 1758). It should be noted that EFETOV-2 (the racemic mixture of R- and Senantiomers of 2-butyl 2-dodecenoate) was more active than EFETOV-S-2 (R-enantiomer). In 2016: Gästrikland, Rönnåsen – 400–420 males attracted to EFETOV-2 and 145–160 males attracted to EFETOV-S-2; Skåne, Hörröd – 26 males attracted to EFETOV-2 and 16 males attracted to EFETOV-S-2; Ravlunda – 155 males attracted to EFETOV-2 and 39 males attracted to EFETOV-S-2. The data for 2017 are: Gästrikland, Rönnåsen – 20 males attracted to EFETOV-2 and 3 males attracted to EFETOV-S-2; Skåne, Hörröd – 103 males attracted to EFETOV-2 and 32 males attracted to EFETOV-S-2; Ravlunda – 32 males attracted to EFETOV-2 and 5 males attracted to EFETOV-S-2. The lower number in 2017 is mainly due to more unfavorable weather and thus fewer trials than in the previous year. These results correspond well with the fact that the males of another subspecies A. (A.) statices drenowskii (Alberti, 1939) were also mainly found in traps with EFETOV-2 during investigations in the Thrace Region (European Turkey) in 2016 (Can et al., 2018).

Arctic and alpine environments present extreme, but different, challenges to survival. We therefore studied the ecological adaptation of the arctic-alpine fritillary Boloria napaea in northern Sweden and compared these results with the eastern Alps. Using mark-release-recapture, we analysed phenology, mobility, activity patterns, change in wing condition and nectar sources. The phenology showed no protandry, but a longer flight period of the females. Wing conditions revealed a linear decay being quicker in males than females. The mean flight distances were higher for males than females (143 vs 92 m). In general, males were more flight active, while females invested more time in feeding and resting. The shortness of the flight period in the Arctic is apparently a particular adaptation to these harsh conditions, not even allowing protandry, and constraining all individuals to hatch during a short period. These conditions also forced the individuals to concentrate on flight and alimentation. In general, Arctic and Alpine populations of B. napaea show few differences, but the species seems to be even better adapted to the northern environments. Thus, the short temporal separation of these populations seems not to have been sufficient for a divergent adaptation in the southern mountains.

European Union and Swedish national energy policy and energy objectives state an increased interest in transition of energy systems to more efficient use of energy, as well as increased use of renewable sources of energy. Horse manure is a potential resource available for renewable energy. Horse manure is sometimes considered a waste problem, resulting in research of possible energy recovery processes, such as combustion and anaerobic digestion. In this study 13 energy actors’ experiences of horse manure were explored by means of interviews and e-mail. Five related to combustion of horse manure and eight related to anaerobic digestion. The aim was to make a compilation of their knowledge and from the results identify how horse manure could be made more attractive as an energy resource. The challenges the actors face are mainly connected with horse manure being a heterogeneous material, primarily due to its bedding content (straw, wood bedding, etc.), and occasionally to other types of added waste. These unpredictable variations in the substrate as well as impurities like sand make it more difficult for plants to have standard procedures for processing horse manure. The view that bedding material needs to be specifically straw pellets and that all impurities should be kept out of the collected horse manure for anaerobic treatment was also expressed. Horse manure as part of co-combustion processes was perceived as a fuel with capacity to contribute to plant economy as it gives revenue from gate fees and could reduce costs for its NO_x reducing capacity. Another view was that grate furnaces could possibly be more suitable than fluidized beds as incineration technology. However, problems with odour made two plants end their combustion trials. In farm-scale incineration horse manure required a lot of monitoring and co-combustion with pellets in order to maintain an effective process. When compiling all available information this study has a number of suggestions for how horse manure should be treated already at the production stage in order to be a more versatile resource in energy recovery processes. The recommendation is to keep horse manure dry (transports and incineration), avoid initiation of composting processes (AD and incineration), sort the waste = no added other waste (AD), and depending on intended AD-treatment process, use a specific bedding type. Most of these issues may be solved by supplier’s involvement in the supply chains for resource recovery, i.e. closing natural cycles of plant nutrients and energy recovery.

Naturcentrum AB har på uppdrag av Länsstyrelsen i Västra Götaland genomfört inventeringar av naturvårdsintressanta arter på kalkhällmarker i östra Dalsland. Inventeringen har fokuserat på särskilt intressanta arter t ex rödlistade arter, sällsynta arter m m, inom grupperna fjärilar, bin, lavar, mossor och marksvampar. Dessutom har presenteras spridda observationer inom andra grupper, till exempel tvåvingar och trollsländor.

De dalsländska kalkrika lerskifferhällmarkerna utgörs av någon mil breda, omvandlade berggrundsstråk i de mellersta och östra delarna av landskapet. Dessa kalkmarker skiljer sig från de geologiskt yngre och sedimentära kalkområdena som är typiska för till exempel Öland och Gotland. Förutsättningarna för floran och faunan i Dalslands kalkområden är unika genom det milda och fuktiga klimatet och att markke- min avviker något från de flesta andra kalkrika trakterna i Sverige. Dessa specifika förhållanden gynnar en lång rad sällsynta eller rödlistade arter.

Fyra av de besökta områdena ligger på Ryrhalvön norr om Köpmannebro och den femte vid Ånimskogs kyrka. Samtliga delområden utgörs av västvända branter i direkt anslutning till sjöarna Ånimmen och Östebosjön. Miljöerna är generellt öppna och det västvända läget skapar ett varmt och solexponerat mikroklimat. I anslutning till de kala hällarna finns partier med tunna, kalkhaltiga jordlager och grusmarker. Graden av beskogning varierar både inom och mellan de olika delområdena.

Inventeringarna genomfördes under några dagar under sommaren 2006 samt med en dags kompletterande lavinventering under februari 2008. Totalt på träffades 24 rödlistade arter fördelade enligt följande; sju fjärilsarter, två biarter, tre lavar, sex olika mossor och sex arter av svampar. Flera av dessa är ytterst sällsynta och har sin huvudsakliga utbredning i landet på dessa kalkrika lerskifferhällar. Vidare noterades ett 30-tal nya arter för landskapet Dalsland. Det största antalet nya fynd gjordes inom gruppen insekter vilket visar att kännedomen om landskapets insektsfauna är mycket bristfällig.

Klot-tegellaven Psora globifera är klassad som starkt hotad (EN) och har huvuddelen av sina kända före- komster i kalkrika områden i Dalsland. Arten växer på lättvittrade, solexponerade, kalklerskifferhällar. I delområde 3 förekommer arten rikligt och i delområde 4 något mera sparsamt. Klotsporig skifferlav Sarcogyne distinguenda (VU) är en annan mycket sällsynt lav med få kända lokaler i landet av vilken den ena utgörs av delområde 5 (Carlsson 1998). Arten är knuten till klippor av kalklerskiffer. Det stora antalet arter gelélavar Collema spp. (sju stycken) är anmärkningsvärt även om ingen av arterna är rödlistade. Av mos-sorna bör särskilt nämnas hår-rosettmossa Riccia ciliata (VU), dvärgrosettmossa Riccia warnstorfii (VU) och trubbklockmossa Encalypta mutica (NT) vilka alla är mer eller mindre knutna till kalkhällar eller kalkrika jordar. Rosettmossorna växer rikligt i delområde 1 medan trubbklockmossan, som omfattas av habitatdi-rektivet inom Natura 2000, noterades i delområde 5. Brun fingersvamp Clavaria pullei (EN) noterades på gräsmarkerna i delområde 5. Arten verkar vara knuten till öppna och hävdade kalkrika marker. Bland in-sekterna utgör nyponsandbiet Andrena nitida (VU), fibblesandbiet A. fulvago (NT) och jungfrulinpraktmal Hypercallia citrinalis (NT) några av de mest anmärkningsvärda arterna. Nyponsandbiet som noterades i del-område 1 är mycket sällsynt och observerades senast 1949 i Dalsland.

Inventeringarna som utförts är av stickprovskaraktär och det bedöms som sannolikt att fler värdefulla arter kan påträffas vid fördjupade inventeringar. Detta gäller både de behandlade delområdena och kalk-lerskiffermarker i allmänhet.

Noctu tertia was introduced as a new species for Northern Europe in the annual review of Macrolepidoptera records from Sweden 2017 (Palmqvist 2018). The current article describes the observations and studies underlying this report. An immigration of presumed Noctua janthina females with non-typical characteristics reaching Gotland during late September 2015 aroused our interest and triggered a more thorough investigation. Examination of their genitalia revealed that several of the captured specimens exhibited characteristics that were identical to those of Noctua tertia. We then extended our studies to a larger material including females with a wide range of variations in wing pattern and coloration and of males with typical janthina/tertia appearance. In total we have identified eleven Noctua tertia four males and seven females, most of them from Gotland but also three from Skåne. The oldest specimen was from 1988 and the newest from 2017. Available information of the geographical distribution of N. tertia is reviewed and the characteristics and biological information of the species in the Noctua janthe/janthina/tertia complex is further developed and discussed.

We provide a comprehensive overview of those Lepidopteran invasions to Europe that result from increasing globalisation and also review expansion of species within Europe. A total of 97 non-native Lepidoptera species (about 1% of the known fauna), in 20 families and 11 superfamilies have established so far in Europe, of which 30 alone are Pyraloidea. In addition, 88 European species in 25 families have expanded their range within Europe and around 23% of these are of Mediterranean or Balkan origin, invading the north and west. Although a number of these alien species have been in Europe for hundreds of years, 74% have established during the 20th century and arrivals are accelerating, with an average of 1.9 alien Lepidoptera newly established per year between 2000–2007. For 78 aliens with a known area of origin, Asia has contributed 28.9%, Africa (including Macaronesian islands, Canaries, Madeira and Azores) 21.6%, North America 16.5%, Australasia 7.2% and the neotropics just 5.2%. The route for almost all aliens to Europe is via importation of plants or plant products. Most alien Lepidoptera established in Europe are also confined to man-made habitats, with 52.5% occuring in parks and gardens. We highlight four species in particular, Diaphania perspectalis, Cacyreus marshalli, Cameraria ohridella and Paysandisia archon, as the most important current economic threats.

Red Lists are very valuable tools in nature conservation at global, continental and (sub-) national scales. In an attempt to prioritise conservation actions for European butterflies, we compiled a database with species lists and Red Lists of all European countries, including the Macaronesian archipelagos (Azores, Madeira and Canary Islands). In total, we compiled national species lists for 42 countries and national Red Lists for 34 of these. The most species-rich countries in Europe are Italy, Russia and France with more than 250 species each. Endemic species are mainly found on the Macaronesian archipelagos and on the Mediterranean islands. By attributing numerical values proportionate to the threat statuses in the different national Red List categories, we calculated a mean Red List value for every country (cRLV) and a weighted Red List value for every species (wsRLV) using the square root of the country’s area as a weighting factor. Countries with the highest cRLV were industrialised (NW) European countries such as the Netherlands, Belgium, the Czech Republic and Denmark, whereas large Mediterranean countries such as Spain and Italy had the lowest cRLV. Species for which a Red List assessment was available in at least two European countries and with a relatively high wsRLV (≥ 50) are Colias myrmidone, Pseudochazara orestes, Tomares nogelii, Colias chrysotheme and Coenonympha oedippus. We compared these wsRLVs with the species statuses on the European Red List to identify possible mismatches. We discuss how this complementary method can help to prioritise butterfly conservation on the continental and/or the (sub-)national scale.

Ecosystem engineers affect other organisms by creating, maintaining or modifying habitats, potentially supporting species of conservation concern. However, it is important to consider these interactions alongside non-engineering trophic pathways. We investigated the relative importance of trophic and non-trophic effects of an ecosystem engineer, red deer, on a locally rare moth, the transparent burnet (Zygaena purpuralis). This species requires specific microhabitat conditions, including the foodplant, thyme, and bare soil for egg-laying. The relative importance of grazing (i.e., trophic effect of modifying microhabitat) and trampling (i.e., non-trophic effect of exposing bare soil) by red deer on transparent burnet abundance is unknown. We tested for these effects using a novel method of placing pheromone-baited funnel traps in the field. Imago abundance throughout the flight season was related to plant composition, diversity and structure at various scales around each trap. Indirect effects of red deer activity were accounted for by testing red deer pellet and trail presence against imago abundance. Imago abundance was positively associated with thyme and plant diversity, whilst negatively associated with velvet grass and heather species cover. The presence of red deer pellets and trails were positively associated with imago abundance. The use of these sites by red deer aids the transparent burnet population via appropriate levels of grazing and the provision of a key habitat condition, bare soil, in the form of deer trails. This study shows that understanding how both trophic and non-trophic interactions affect the abundance of a species provides valuable insights regarding conservation objectives.

This is the 47th consecutive annual report of new and interesting finds of Macrolepidoptera in Sweden, and also a compilation of new provincial records. This summer was also warmer than average, with periods of favourable S-SE winds, which brought many migrating Lepidoptera to Sweden. Five species were for the first time recorded in Sweden. These are: Isturgia arenacearia, Ascotis selenaria, Eublemma purpurina, Caradrina kadenii and Leucania loreyi. Many other migrant moths like Agrius convolvuli, Macroglossum stellatarum, Hyles livornica, Thaumetopoea processionea, Eilema griseolum, Grammodes stolida, Catocala fulminea, C. adultera, C. elocata, Helicoverpa armigera, Autographa mandarina, Spodoptera exigua, Blepharita amica, Mythimna vittelina, Peridroma saucium, Xestia ditrapezium, and Nycteola asiatica were also recorded. This report also gives numerous examples of native butterflies and moths expanding northwards in the country due to the climate change. The number of Macrolepidoptera species found in Sweden are now 1126, of which 16 are introduced. Possibly the most remarkable observation this year is the rediscovery of Gazoryctra ganna, in northernmost Sweden, 172 year after the last and only time the species has been found in the country. In addition, a second find of the enigmatic species Mniotype bathensis from 2015 in Jämtland is also extraordinary. This observation further supports the view that the species is resident in the southern Scandinavian mountain region. Unfortunately, the situation for the endangered butterfly Melitaea britomartis is becoming extremely critical. No observations at all could be done this year in the two remaining habitats in Småland and Västmanland (Artportalen).

This is the 48th annual report of new and interesting finds of Macrolepidoptera in Sweden with a compilation of new provincial records. This season was warm compared with what was previously average in Sweden, except for the north-easternmost parts of the country and some areas in the Swedish mountains, which partly experienced cool and wet weather. However, the summer temperatures were much less extreme than in 2018, with some cool spells as well. The presence of Gazoryctra ganna as a native species was confirmed by additional observations on the same site as in previous year, plus the discovery of new location further north in the Torne valley. A large number of species continues to expand northwards and inlands like Idaea emarginata, Apeira syringaria, Cryphia algae, Apameaepomidion, Cirrhia ocellaris, Atethmia centrago, Agrotis puta, Apamea scolopacina; and some also are rounding the Gulf of Bothnia from the east like Globia sparganii and Noctua comes. Many migrant species were found in periods with S-SE winds like Agriusconvolvuli, Acherontia atropos, Macroglossum stellatarum, Hyles euphorbiae, Orthonamaobstipata, Hypena lividalis, Eublemma purpurina, Heliothis peltigera, Heliothis adaucta, Heli-coverpa armigera, Spodoptera exigua, Fabula zollikoferi, Mythimna vitellina, Agrotisbigramma, Xestia ditrapezium and Nycteola asiatica. The globally widespread moth Utetheisapulchella was recorded for the first time in Sweden on the Baltic islands Öland and Gotland. The butterfly Melitaea britomartis (CR) could not be rediscovered for the second year and must now be considered as extinct in Sweden. In addition, the butterfly Plebejus argyrognomon(EN) was not found this year and appears to have gone extinct. Both these butterfly specieshave almost unique subspecies in Sweden which makes this loss very serious. 

This is the 49th consecutive annual report of new and interesting finds of Macrolepidopterain Sweden including a compilation of new provincial records, most of the new records are retrieved from the Swedish Species Observation System https://www.artportalen.se. The trend with warmer climate and thus longer vegetation periods continues to have a strong impact on faunal changes and the distribution of the Swedish Lepidopteran fauna. New species, mainly from south and east find their way almost yearly to our country. In 2021 three new species were observed for the first time in Sweden: Amata phegea, Mormo maura and Xylomoia graminea. The trend with expansion mainly northwards and inlands is still strong among species like: Zygaena minos, Pararge aegeria, Apatura ilia, Araschnia levana, Idaea ochrata, Mesoleuca albicillata, Hydrelia sylvata, Melanthia procellata, Eupithecia abbreviata, Cucullia scrophulariae, Cryphia algae, Hoplodrina ambigua, Atethmia centrago, Conisania luteago, Noctua interposita, Epilecta linogrisea, Meganola albula but also among many other species. A new and remarkable feature in the new climatic conditions is that species like Pararge aegeria, Watsonalla binaria and many others can produce full or partial second or even third generations in their just recently reached northernmost range limits. An impressive number of migrants found their way to Sweden, mostly from August to October. Among the more noteworthy are: Argynnis laodice, Acherontia atropos, Scopulani gropunctata, Orthonama obstipata, Horisme corticata, Narraga fasciolaria, Isturgia arenacearia, Rhyparia purpurata, Catocala elocata, Catocala electa, Chrysodeixis chalcites, Heliothis adaucta, Helicoverpa armigera, Caradrina kadenii, Mythimna vitellina, Peridromasaucium, Agrotis bigramma, Xestia ditrapezium, Nycteola asiatica. In northernmost Sweden Gazoryctra ganna was found for the third successive year, showing that the moth is resident in Sweden and presumably has been so during all the year it was not found. Also, one new, small population of Lycaena helle was found indicating that the species still lingers on 3-4 localities in Northernmost Sweden. In Skåne in southernmost Sweden the moths Lithostege farinata, Hadena filograna have been observed again after many years absence. They have been considered as nationally respectively regionally extinct, but hopefully new influx or some concealed unknown population may rescue the species survival in Skåne again. The number of macrolepidoptera found in Sweden is now 1130, of which 16 are introduced.

Mean global temperatures have risen this century, and further warming is predicted to continue for the next 50–100 years. Some migratory species can respond rapidly to yearly climate variation by altering the timing or destination of migration, but most wildlife is sedentary and so is incapable of such a rapid response. For these species, responses to the warming trend should be slower, reflected in poleward shifts of the range. Such changes in distribution would occur at the level of the population, stemming not from changes in the pattern of individuals' movements, but from changes in the ratios of extinctions to colonizations at the northern and southern boundaries of the range. A northward range shift therefore occurs when there is net extinction at the southern boundary or net colonization at the northern boundary. However, previous evidence has been limited to a single species or to only a portion of the species' range. Here we provide the first large-scale evidence of poleward shifts in entire species' ranges. In a sample of 35 non-migratory European butterflies, 63% have ranges that have shifted to the north by 35–240 km during this century, and only 3% have shifted to the south.

Whittleia retiella (Newman, 1847) is a threatened salt marsh species of the bagworm moth family Psychidae. For its preservation it is necessary to develop efficient tools to survey its distribution and habitat requirements in order to use appropriate conservation methods. Such tools may be pheromone-based monitoring systems, which have documented efficacy in establishing the occurrence of cryptic insect species in nature. By using gas chromatography combined with electroantennographic detection (GC-EAD), we found two compounds in female W. retiella headspace samples and whole-body extracts that elicited electrophysiological activity in male antennae. Gas chromatograpy coupled with mass spectrometry (GC-MS) operating in electron impact (EI) mode and comparison of the analytical data with those of synthetic reference compounds showed the chemical structures of these putative pheromone components to be (1S)-1-methylpropyl (5Z)-dec-5-enoate and 1-methylethyl (5Z)-dec-5-enoate. Field assays using baits loaded with synthetic compounds revealed that conspecific males were attracted to (1S)-1-methylpropyl (5Z)-dec-5-enoate alone or in combination with 1-methylethyl (5Z)-dec-5-enoate, whereas 1-methylethyl (5Z)-dec-5-enoate neither attracted nor repelled males in the field assays when tested alone. This study shows the potential of using (1S)-1-methylpropyl (5Z)-dec-5-enoate for monitoring W. retiella to gather more detailed information about the geographic distribution and habitat needs of this rare moth.

Global warming and the change of butterfly distributions: a new opportunity for species diversity or a severe threat (Lepidoptera)? In order to assess the influence of climatic changes on the distribution of insects, the ranges of nonmigratory European butterfly species have been studied. This study revealed that the northern limits of 32 (64%) of 52 species have expanded northwards during the 20th century. The southern limits of ten (25%) of 40 species have retracted northwards. The example of the Peacock butterfly (Inachis io) is given to illustrate the response to climatic changes of a species of which the range is not restricted by habitat choice. The northern limit of its range shows a considerable shift to the north during warm periods, and a southward retraction during cooler periods. Several other species showed the same pattern. These results are followed by a discussion of the impact of climate change on species diversity.

The ichneumonid genus Cidaphus Förster, 1869, and its three known European species Cidapus areolatus (Boie, 1850), C. alarius (Gravenhorst, 1829) and C. atricillus (Haliday, 1839) are reported as new to Sweden based primarily on specimens collected in light traps during projects monitoring nocturnal moths. The available material indicates that C. areolatus is a rather abundant and widespread species throughout most of the southern and central parts of Sweden. The trapping data indicates that it flies in one prolonged generation from July until October. Cidaphus atricillus and C. alarius are both rather rare and their distribution is much less clear, but both species appear to fly earlier in the season than C. areolatus.