To compile the species list, we relied exclusively on morphological information and descriptions. Reports and potential advancements from molecular biology (e.g., barcoding or metabarcoding) were intentionally excluded unless they aligned with both genetic and morphological approaches, contributed to a morphological description of the collected or reported taxa, and were published by specialists in the order (e.g., Wagner et al. 2017; Yanai et al. 2022).

The species list presented here is primarily based on the foundational work of Buffagni et al. (2003, 2009) and a study on the distribution of Ephemeroptera species published in 2006 (Belfiore 2006). These three publications draw on the existing literature available at the time of their release, as well as on the authors’ direct knowledge of species occurrence and distribution, derived from their examination of material in their collections. This material, which has been expanded with additional collections after 2008, represents more than 50 years of sampling and serves as the basis for the current work. However, this material has not been uniformly studied, leaving many regions of Italy insufficiently explored. For instance, species in the Italian Alps have yet to be thoroughly investigated. Conversely, certain genera in Sardinia and Sicily have received particular attention due to the high levels of endemism observed in these regions, which have drawn significant interest from researchers.

With a few rare exceptions, no indication is given of the extinction risk of the species and its IUCN category. In fact, it is not possible to provide reliable information at this stage, given the obvious need for taxonomic revision.

The book by Bauernfeind and Soldán (2012) on European Ephemeroptera served as the primary reference for nomenclature, including genera and species names. The only exceptions are the Baetidae Acentrella Bengtsson, 1912 Alainites Waltz, McCafferty & Thomas, 1994, Nigrobaetis Novikova & Kluge, 1987, and the Leptophlebiidae Euthraulus Barnard, 1932, which are treated here as genera because of their generally accepted and widespread use. For the sake of simplicity, taxonomic affiliation and authority are given for all species in Table 1.

Given the importance of establishing verifiable references for the identification of species present in Italy, a specimen vouchering process supported by COI barcoding (AB, unpublished) was initiated as part of the ITINERIS project, with best-practice procedures for archiving of selected Ephemeroptera based on GBIF and Darwin Core standards.

At least two primary needs can be identified when drafting species distributions. The first is to provide highly detailed information about the specific areas and locations where species have been found. The second is to identify and summarise broader distribution patterns, providing a general overview and allowing comparison and correlation of data across species. Due to the absence of a centralised repository for Ephemeroptera distribution data and the resulting gaps in detailed knowledge for many areas, the second approach has traditionally been preferred. In Buffagni et al. (2009), a book focusing on European Ephemeroptera, species distribution is presented according to Illies’ ecoregions (Illies 1978). For Italy, this framework includes Ecoregion 3 (Italy), encompassing Sardinia and Sicily, and Ecoregion 4, corresponding to the Alps. In earlier checklist efforts for Italian fauna (i.e., Minelli et al. 1993, 1995; Stoch and Minelli 2004), Italy was instead divided into two macro-areas, North and South, with the fauna of Sardinia and Sicily treated separately. Taking a contrasting approach, the ckMAP project (Ruffo and Stoch 2006) presented the distribution of numerous Italian species, including Ephemeroptera (Belfiore 2006), using geographic quadrants of approximately 10 × 10 km. However, much of the data used to determine these distributions—drawn from available literature and a taxonomy that has since undergone extensive revisions at the European level—would now likely require significant updating. There is therefore little point in undertaking such a review of species distributions at this time, which could instead be one of the objectives of ongoing activities, with a time horizon of 5–10 years.

For this work, we opted for an intermediate scale, dividing the Italian territory into six main areas. These are: the Alps, the lowland and hilly areas of the Po basin (≈ < 300 m, including the lowlands of Friuli-Venezia Giulia and the lower Adige catchment), the northern Apennines, the central-southern Apennines, Sardinia, and Sicily (Fig. 1).

Figure 1. 

Map of the six macro-areas used in the work to describe the distribution of Ephemeroptera species in Italy. Apart from the delimitation of Sardinia and Sicily, the other limits must be more properly considered as bands.

The distinction between the Alps/Apennines and the lowland/hilly areas of the Po basin is based on ecological factors that influence species distribution. More specifically, to define the boundary between the lowland/hilly areas and the mountain areas, we used the boundaries already defined for hydro-ecoregions (Chandesris et al. 2006; Wasson et al. 2006). Hydro-ecoregions (HERs) are officially used in the Italian river typology (see Suppl. material 1 and: Buffagni et al. 2006; MATTM 2008: Annex I, fig. 1.1) for the Water Framework Directive (WFD), also for the assessment of ecological status based on benthic macroinvertebrates. Hydro-ecoregions 5, 6, 7 (Italian part), and 8 together make up the part of the territory referred to here as the lowland and hilly areas of the Po basin (see Annex 1). Sardinia and Sicily are treated separately due to the high number of endemic species on these islands. The division of the Apennines into northern and central-southern zones roughly reflects a discontinuity in Ephemeroptera distribution previously identified by Belfiore (1994a). For convenience and consistency with the data collected under the WFD, this boundary has been aligned with the division between HERs 10, 11, 14, and HERs 12, 13, 15 (Annex 1). In any case, with the exception of Sardinia and Sicily, these zones are approximations. Actually, the dividing lines shown in Fig. 1 should be interpreted as broad bands rather than precise boundaries, as the current knowledge of species distribution is not detailed enough to accurately define the separations between these areas.

Table 1 provides a comprehensive list of Ephemeroptera species currently believed to be present in Italy, grouped by family according to the classification system outlined by Bauernfeind and Soldán (2012). For each of the six previously described macro-areas, the table indicates the possible presence of each species. Additionally, it notes whether a species is endemic to Italy.

In total, we report the presence of 106 species of Ephemeroptera in Italy. Of these, 29 species are endemic, accounting for approximately 27% of the total. Among the six macro-areas, the Po Valley hosts the highest number of species, with 63 recorded, followed by the central-southern and northern Apennines, reporting 56 and 55 species, respectively. Approximately 30 species are reported for both Sicily and the Alpine region, while Sardinia has the lowest total, with just 23 species.

An examination of the number of species endemic to Italy or southern Europe by macro-area reveals interesting patterns. In the Po Valley, only five endemic species are recorded, likely reflecting the overlap of species common to other European regions. The northern Apennines show ~ 11% endemic species. Endemism rises significantly in Sicily, where it exceeds 18%, and in the central-southern Apennines, where it reaches 23%. Sardinia, despite hosting the fewest species overall, exhibits a remarkably high level of endemism, with > 40% of its species classified as endemic.

Focusing on endemic species that are unique to a single area (i.e., present in only one of the six macro-areas adopted here to present species distributions) provides further insights. Overall, as many as 20 of the 29 endemic species believed to be present in Italy are found in only one of the six macro-areas. In the Po Valley and the northern Apennines, the proportion of species endemic to these regions remains < 5%. This figure increases to nearly 10% in the central-southern Apennines and Sicily. Sardinia stands out with nearly 35% of its species being endemic solely to the region (including Corsica), making it the richest biodiversity hotspot for endemic mayflies in Italy. The high levels of endemism observed in areas such as Sardinia and Sicily suggest the potential for undiscovered species, particularly in Sicily, where additional endemic Ephemeroptera may still await description. In fact, to date not all families/genera have been studied with the same emphasis. These findings underscore the importance of targeted biodiversity studies to further refine our understanding of Italian mayfly diversity and endemism.

According to Bauernfeind and Soldán (2012), eight of the taxa listed here are classified as species inquirenda, meaning that the available knowledge is insufficient to confirm their validity with certainty. Consequently, data regarding their presence and distribution should be interpreted with caution. These taxa are not included in the calculation of species present in Italy, except for three species discussed in the text. A subset of these species has not been recognised or reported—if collected—since their initial taxonomic description. Additional information on these taxa is provided in the following paragraphs.

Since the most recent publication providing synoptic information on Italian Ephemeroptera (Buffagni et al. 2009), two new species have been described based on material collected in Italy: Electrogena brulini Wagner, 2017, identified in small streams in the hilly regions of Lombardy (Wagner et al. 2017), and Alainites bengunn Yanai & Gattolliat, 2022, discovered in Sardinia (Yanai et al. 2022).

The following section provides commentary on some of the mayfly species found in Italy, aiming to highlight potential issues or critical situations of various kinds. For the four most represented families—Heptageniidae, Baetidae, Leptophlebiidae, and Caenidae—the species-specific comments are grouped within the same paragraph for clarity and coherence. With a few exceptions, we have not made a comparison with the distribution of species in neighbouring countries. Since the Ephemeroptera fauna of these countries is usually better known than that of Italy, we do not believe that such a comparison would have been particularly valuable, especially at this stage of taxonomic revision in Italy. Moreover, such an activity would have implied a different approach to the work, which is not in line with the proposed objectives.

The situation of Ametropus fragilis is discussed in greater detail than other species because it highlights some interesting and potentially generalisable challenges regarding the detection and actual presence of rare taxa in Italy.

In the recent history of Ephemeroptera research, Ametropus fragilis was first collected in the lower stretch of the Adige River during the winter of 1993–1994 (Turin et al. 1997), marking the species’ first documented occurrence in Italy. Its presence was initially attributed to a possible accidental introduction through fish restocking practices involving stocks imported from Eastern European countries. However, a subsequent study by Sartori and Bauernfeind (2020) revealed that an adult male of this species, collected in Italy during the 19^th century, is preserved in the Pictet collection at the Geneva Museum. Although Pictet correctly identified the specimen, he did not report the species’ presence in Italy (Sartori and Bauernfeind 2020). This evidence suggests that Ametropus fragilis has historically occurred in Italy but was not observed again until its rediscovery in 1993 (Turin et al. 1997). This more recent collection occurred during a biomonitoring activity for which a specific identification for mayflies was not expected (Turin et al. 1997). The genus Ametropus was not reported in Italy at the time, making the discovery appear “odd” and prompting further investigation. It is plausible that if the species had belonged to a multi-species genus already documented in Italy, it might have gone unnoticed. Further discoveries, such as the first collection of the species in Croatia (Ćuk et al. 2015) and other neighbouring countries, combined with its apparent survival in Italy for > 150 years without detection, underscore the need for targeted research in suitable habitats. These include large rivers with sandy or muddy substrates and the presence of organic detritus.

The fragmented history of Ametropus fragilis carries important implications. For certain species, extinction may be only apparent, and populations may persist undetected for decades in specific conditions. For example, nymphs of A. fragilis were recorded for the first time in the Ipeľ (Ipoly) river on the Slovak-Hungarian border (Macko and Derka 2021), although the river had previously been studied relatively intensively by authors from both sides of the border (Macko et al. 2023). The rediscovery of Ametropus fragilis, a species that is relatively easy to identify, raises the possibility that similar scenarios could exist for more cryptic or less distinctive species. These might go unnoticed during routine sampling or standard biomonitoring protocols. In addition, the combination of habitat fragmentation in rivers and the low population densities exhibited by many Ephemeroptera species underscores the importance of targeted sampling efforts. Such efforts should aim to identify faunal “emergencies” and contribute to a more accurate picture of overall biodiversity.

The taxonomic status within the family Baetidae is both complex and dynamic. Molecular methods have revealed the existence of numerous putative and/or undescribed species across various genera and species groups (Cardoni et al. 2015; Tenchini et al. 2018; AB unpublished). For instance, several species are collectively identified under the name Alainites muticus (see Yanai et al. 2022), as well as Baetis ingridae. Regarding the latter, molecular techniques have demonstrated the presence of three distinct species from the rhodani group in Sardinia (Bisconti et al. 2016). Similarly, molecular biology and barcoding techniques have clarified that the taxon previously referred to as Baetis fuscatus actually encompasses a species complex (Cardoni et al. 2015; El Yaagoubi et al. 2023), with many of these species awaiting formal description.

Baetis pavidus, was once prevalent and relatively abundant in the Po Valley. However, during the past decade, its distribution in northern Italy, including its type locality, has declined sharply—likely as a consequence of climate change—with no recent specimens available from this region. The species has also nearly vanished from central Italy. In contrast, some specimens collected in Sicily have been identified as presumably belonging to this species.

Procloeon lacustre (Eaton, 1885) and Procloeon nemorale (Eaton, 1885), belonging to the subgenus Pseudocentroptilum Bogoescu, are not included in the list of Italian mayflies because their status is essentially unclear and we have never directly examined material of these species. Both species were described by Eaton in 1885 and have not been reported since. Similarly, Procloeon forlivense (Grandi, 1964) and Cloeon languidum Grandi, 1959, although described from Italy by an Italian author, are not included in the list. These four species, together with Cloeon praetextum Bengtsson, 1914, are considered as species inquirenda by Bauernfeind and Soldán (2012). There are more species of these genera, and perhaps of Centroptilum Eaton, in Italy than are included in the checklist. However, at present we do not have any conclusive elements to clarify the picture regarding these interesting genera.

Alongside the genus Anapos Yanai & Sartori, 2017, represented by a single species in Sardinia, the only other genus in this family with a reasonably accurate understanding of its species composition is Electrogena Zurwerra & Tomka, 1985. This genus has been the focus of extensive research over the years (e.g., Belfiore 1994b, 1995, Belfiore et al. 1997) and a comprehensive review (Belfiore 1996). For other genera, both species-poor ones like Heptagenia Walsh, 1863 and Epeorus Eaton, 1881 and species-rich ones such as Ecdyonurus Eaton, 1868 and Rhithrogena Eaton, 1881, significant changes are expected in the near future. These changes will likely stem from the discovery of previously unreported species and the formal description of new taxa. Indeed, morphological analyses of collected material, supported by ongoing genetic studies (AB unpublished), have revealed the presence of taxonomic entities that cannot yet be confidently assigned to any currently known species.

As far as the taxa of the genus Ecdyonurus present in Italy are concerned, a few species are easily recognised in both adult and larval stages and have a clear status i.e., E. alpinus, E. belfiorei, and E. corsicus, while for all other species taxonomic refinements with the selection of new diagnostic characters would be appropriate. In many cases, a careful analysis of the distributional ranges of different taxa is likely to be an effective aid in interpreting the taxa actually present, making it possible to highlight any discontinuities or gradients in intraspecific morphological variability.

As far as the Rhithrogena genus, we report here the presence of R. savoiensis, which is new for Italy (upstream reaches of river Marecchia, 22.6.2019, C. Belfiore leg. det.). In general, a few species of the genus have a clear status i.e., R. adrianae, R. johannis, R. nivata, R. nuragica, R. reatina, and R. savoiensis. For all the other species, the specific name and attribution should be verified. Consequently, all information available to date on the distribution and ecology of the various species of the genus reported for Italy must be considered with great caution, given the inherent degree of uncertainty of the specific identification itself. According to Tenchini et al. (2018), Rhithrogena sibillina Metzler, Tomka & Zurwerra, 1985 is considered synonymous with Rhithrogena reatina Sowa & Belfiore, 1984 and is therefore not reported in Table 1.

With regard to this family, while being aware that identification at the larval stage is sometimes based on characters that should be reviewed, the situation- compared to other families- seems clearer. For the status of two species, Habroleptoides modesta (Hagen, 1864) and Habroleptoides umbratilis (Eaton, 1884), clarification would be appropriate in general, not only for Italy. Paraleptophlebia ruffoi Biancheri, 1956 and Habroleptoides auberti (Biancheri, 1954) would require further investigation regarding their distribution. The taxon Euthraulus balcanicus Ikonomov, 1961, is clearly distinct from the related species found in Italy, although it is considered a species inquirenda (Bauernfeind and Soldán 2012).

In general, there are probably more species in the macrura group than those currently listed. However, the overall situation and the potential for describing new species is complicated by the high morphological similarity between the taxa, especially in the larval stages, which makes it difficult to highlight the species really present in Italy. A similar argument to that made for the Baetidae, i.e., that some species would be more appropriately considered as groups of species, probably applies to some species of Caenidae. For example, it is very likely that Caenis martae Belfiore, 1984 comprises several cryptic species occurring in different parts of Italy, sometimes even in sympatry.

Caenis belfiorei Malzacher, 1986 is widespread in southern Italy, where it is sympatric with C. pseudorivulorum Keffermüller, 1960. Caenis belfiorei was originally described as a subspecies of C. pseudorivulorum but, according to Buffagni (1997, 1999), it is elevated to the species status. Another species of the pseudorivulorum group is present in Italy, C. beskidensis Sowa, 1973, which seems to be restricted to the northern Apennines.

Across the different families of Ephemeroptera, we have a number of easily identified species whose presence in Italian watercourses seems to have decreased considerably in the last two decades. Although this indication results mainly from the direct activity of the authors not expressly aimed at assessing the range of these species and from occasional analyses of biomonitoring data, it unfortunately seems that the presence of the species is rarer than in the past, although some of them may locally reach high densities where present. Among these species, mention should be made of Ephoron virgo (Olivier, 1791), Oligoneuriella rhenana (Imhoff, 1852), Acentrella sinaica Bogoescu, 1931, Heptagenia coerulans Rostock, 1878 and Nigrobaetis digitatus (Bengtsson, 1912).

Then there are other, relatively rare species whose distribution in Italy has never been really known in detail and which would require specific surveys to confirm their presence and verify the conservation status of their habitats. These include Ephemera vulgata Linnaeus, 1758, Ephemera glaucops Pictet, 1843, Nigrobaetis niger (Linnaeus, 1761), Ecdyonurus zelleri (Eaton, 1885), Ecdyonurus ruffii Grandi, 1953, Rhithrogena nivata (Eaton, 1871), Caenis beskidensis Sowa, 1973, and Caenis lactea (Burmeister, 1839).

Finally, we have five species no longer found after the first collection, which, in four cases, supported the species description. A very interesting and peculiar species, both for its morphology and for the environments it colonises (Schletterer and Füreder 2009), is Prosopistoma pennigerum (Müller, 1785), reported only once from Tuscany, with observations made in 1979 (Bellmann, 2000; Schletterer and Füreder 2009). The species, due to the profound alterations suffered by the environment in which it was collected (i.e., the final stretch of the River Ombrone) is probably extinct.

Although we have not directly analysed specimens of the two species, Ecdyonurus bellieri (Hagen, 1860) and Rhithrogena siciliana Braasch, 1989, which were no longer collected after their description, they are presented in the taxa list. In this case, although they are both species inquirenda, they were described on material collected in Sicily, a land rich in endemism, and we have, therefore, cautiously preferred to record them in the taxa list.

Caenis valentinae Grandi, 1951 and Procloeon calabrum (Belfiore and D’Antonio, 1990), Italian endemics, have not been caught since the collections that allowed their description. Dedicated sampling campaigns are planned in the near future in the hope of confirming the presence of these two species and thus their non-extinction.

The general picture of the Italian Ephemeroptera, briefly described above, allows us to highlight some relevant aspects to guide future research on the taxonomy of this order. A first element, at once of great stimulus for research and of concern, is that several species described on material collected in Italy have not been caught since the initial collection. In some cases, type material appears to have been lost or, where present, is not usable for genetic analysis. The collection of new material from type localities is therefore urgent. Some species are known from only one or a few close localities. In this case, new collections are indispensable, although there is no guarantee of finding the species again. When a species has been described from specimens collected from different areas in Italy, it will be easier to make new collections, but it will be advisable to check whether all specimens belong to a single species, possibly with the aid of genetic techniques, for the possible presence of cryptic species. Consequently, such verification should also be done for possible lectotypes or syntypes, whenever possible.

As mentioned above, there are currently insufficient data for the compilation of a Red List of Italian Ephemeroptera, although this is a matter of extreme urgency. At present, there is no repository for information on the collection of Ephemeroptera species and, in fact, data are archived, in a more or less systematic and organised manner, to manage the authors’ physical collections. At the national level, there are repositories of information at genus or family level. In general, apart from the activities of the authors, few attempts exist in Italy to arrive at a specific identification of the Ephemeroptera.

The focus on Ephemeroptera has traditionally been on running water environments, which are home to many more species than lentic environments. This has therefore led to a lack of knowledge about the species present in ponds and lakes. In any case, the greatest urgency for further knowledge seems to be related to lotic environments, by virtue of their tendency to become temporary (Skoulikidis et al. 2017), with changing community structure and the potential replacement of species from more lotic to more typically lentic (Buffagni 2021). Urgency is particularly linked to global changes, where climate change has exacerbated an already critical situation in some areas and ecosystem categories (Alba-Tercedor et al. 2017). Habitat changes and alterations affect the occurrence and distribution of mayflies and can also affect rare and endemic species (e.g., Buffagni et al. 2016). Similarly, climate change may pose further difficulties in planning focused collections due to the unpredictability of river flows, particularly in the Mediterranean, and may alter expected reference conditions (De Girolamo et al. 2017).

The advent of new genetic techniques and standards for comparing different taxa and defining the boundary between different species can facilitate taxonomic investigation (Yeates et al. 2011). Integrative taxonomy (e.g., Schlick-Steiner et al. 2010) has become an essential tool for taxonomic revisions, including that of Ephemeroptera. In Italy, a systematic barcoding initiative for Ephemeroptera is underway (AB unpublished) and is anticipated to clarify the broader taxonomic framework of major families within a few years. This effort is expected to significantly accelerate the study of Ephemeroptera, enabling a more rapid determination of the number and diversity of taxonomic entities present in Italy. However, challenges will persist in interpreting the identified clades. These must be cross-referenced with their geographical distribution and, crucially, with the morphological characteristics of the collected specimens (e.g., Stoch et al. 2024). Simply recognising clades—or in some cases, defining putative species (e.g., Bisconti et al. 2016)—will not necessarily conclude the taxonomic process, which ideally culminates in the formal description of the identified species. Achieving this will require the involvement of highly skilled researchers proficient not only in genetic methods but also in detailed morphological analysis.

The primary reason for the limited focus on taxonomic studies of Ephemeroptera appears to be the lack of dedicated funding (reason 1). The scarcity of resources for basic research, combined with a broader shift towards more applied scientific topics (reason 2), has rendered taxonomic studies increasingly unattractive, uninteresting, or simply unsustainable for newer generations of researchers in Italy (see Kim 2017, for general considerations on the moribund state of insect taxonomy). This issue will be briefly addressed below. Here, however, we aim to concentrate on the epistemological and gnoseological dimensions of the topic.

Although accurate and reproducible taxonomic identification is the cornerstone of biology, the level of validation of taxonomic identification in entomological studies is often poor (Packer et al. 2018). Notably, since the mid-1990s, no Italian researchers have systematically committed to studying the taxonomy of Ephemeroptera with the goal of addressing the numerous poorly understood aspects of the species present in Italy. Essentially, the principle that inaccurate information could lead to subsequent interpretative errors (reason 3; e.g., Bortolus 2008) has significantly hindered major taxonomic advancements in Italian mayflies for at least two decades. This perception arises from the difficulty of detecting and correcting such inaccuracies solely through the literature. As a result, when identification errors are anticipated, tentative species-level identifications often contribute minimally to the advancement of knowledge while introducing potentially enduring and harmful biases over time. The literature is replete with examples of species names being inaccurately assigned due to limited understanding of taxonomic order, erroneous assumptions about species distribution, or inadequate species definitions by specialists. This issue is partly a consequence of minimal or non-existent funding for taxonomic research—an ineffective strategy that has affected not only Ephemeroptera but a broad range of aquatic taxa. Such a short-sighted approach has also caused lasting harm to research opportunities, restricting the potential for progress in these fields. For example, the lack of resources—particularly preservation tools, infrastructures and dedicated personnel (reason 4; e.g., Engel et al. 2021)—to establish and maintain natural history collections has led to the loss or alteration of many collected mayfly specimens. Frequently, re-examining original material or preserved specimens proves difficult, if not impossible. These specimens are often fragmented or partially damaged during initial microscopic analyses, and many have been entirely lost over the decades (reason 5). This situation severely hampers the application of the scientific method, limiting the ability to refute or confirm historical (and published) findings. This challenge is particularly evident for numerous species, including potential endemics, described during the 19^th century or the mid-20^th century. The task of rediscovering and recollecting species found decades ago—often poorly described—within a natural environment that has undergone significant changes, coupled with the necessity of integrating different methodological approaches (e.g., genetics and morphology), makes this undertaking exceptionally demanding.

Comparative tables and the quantification of diagnostic characteristics for species identification and divergence—along with the species descriptions and reviews compiled by the authors—are likely outdated. These are often based on a limited selection of species present in Italy (and Europe), as recent biomolecular analyses increasingly indicate. This suggests that interspecific differences may have been conflated with intraspecific variability, or that inappropriate diagnostic characteristics were selected. For example, Ecdyonurus austriacus was not recorded in Italy when the review of Italian species in the helveticus group was compiled (Belfiore and Buffagni 1994), but its presence is now considered highly likely. Thus, it is possible that some of the nymphs previously attributed to E. alpinus may actually belong to E. austriacus. A similar scenario could apply to Caenis martae, whose purported distribution and morphological variability suggest the potential coexistence of similar, closely related species in Italy. As mentioned above, a further examination of the material used for taxonomic reviews is needed to confirm or refute the identifications and the assignment of quantitative thresholds to diagnostic characters. In practice, this task appears challenging, and new specimens are currently being collected for refinement. However, such work should be conducted for most species groups of Italian mayflies, requiring significant effort and dedicated research. Will it be possible to find/form experts available to complete such a time consuming work that is – additionally – not that much appreciated by scientific evaluation boards (e.g., too low Impact Factor: Agnarsson and Kuntner 2007)? Most of the Ephemeroptera books cited in the introduction of this manuscript (e.g., Grandi 1960; Belfiore 1983; Bauernfeind and Soldan 2012; Buffagni et al. 2009) took months or years of work to be written and are based on skills acquired over years or decades. None of them even have an Impact Factor: in different historical and research periods and contexts, their value is, however, indisputable. Nowadays, there is the believe that fundamental (vs. applied) research has a great value. In the meantime, innovative ideas, conceptions and papers are encouraged, pushing quality of research (e.g., few papers targeting Nature or Science) instead of quantity (more papers of ‘lower’ level). The description of ‘new’ species – we still expect many in Europe – is per se innovative and, of course, intrinsically a piece of fundamental research, which is crucial for understanding, managing and teaching biodiversity (Kim 2017; Härtel et al. 2023). Understanding local species and incorporating their study into environmental education should be central to fostering a deeper interest in the natural environment, particularly among younger generations (Genovart et al. 2013). Nevertheless, the description of new species, although at the heart of the study of biodiversity, is confined to a small number of specialist publications, with Impact Factors significantly lower than most journals devoted to more applied research. The description of new species- if not perhaps of a new Hominidae- is unlikely to find a place in the more emblazoned journals. In the hope that the world of research will find a balance between the performance needs of young researchers, environmental urgencies and the need to quantify and protect biodiversity, Italy is now offering a perspective for new generations with the creation of the National Biodiversity Future Centre. NBFC organises PhD courses on biodiversity and taxonomy, to encourage, instruct and accompany young researchers on the long way of taxonomic investigation. Hopefully, some effort will be devoted to aquatic organisms, too, beyond the minimal scheduled life of the Centre (2022–2025).

The authors have declared that no competing interests exist.

No ethical statement was reported.

NBFC - Project funded under the National Recovery and Resilience Plan (NRRP), Mission 4 Component 2 Investment 1.4 - Call for tender No. 3138 of 16 December 2021, rectified by Decree n.3175 of 18 December 2021 of Italian Ministry of University and Research funded by the European Union – NextGenerationEU; Project code CN_00000033, Concession Decree No. 1034 of 17 June 2022 adopted by the Italian Ministry of University and Research, CUP B83C22002930006, Project title “National Biodiversity Future Center - NBFC”.

ITINERIS - IR0000032 – ITINERIS, Italian Integrated Environmental Research Infrastructures System (D.D. n. 130/2022 - CUP B53C22002150006) Funded by EU - Next Generation EU PNRR- Mission 4 “Education and Research” - Component 2: “From research to business” - Investment 3.1: “Fund for the realisation of an integrated system of research and innovation infrastructures” CUP B53C220021500006).

Both authors contributed to the study conception and design. The first draft of the manuscript was written by Andrea Buffagni and both authors commented on previous versions of the manuscript. Both authors read and approved the final manuscript.

Andrea Buffagni https://orcid.org/0000-0002-3944-1861

Carlo Belfiore https://orcid.org/0000-0002-0061-8658

All of the data that support the findings of this study are available in the main text or Supplementary Information.