New information of the biodiversity of the nymphalid family (Insecta, Lepidoptera, Nymphalidae) species collected in Romania’s fauna between 1887–1984

Abstract Background This paper complements the data published thus far about species of the nymphalid family with data collected in Romania’s eight regions between 1887 and 1984 and elsewhere in Europe (Austria, Germany, Croația, the Republic of Moldova, Serbia and Switzerland), including the date and the site of original collection. For the first time, this research presents the collecting information of the species held in the entomological collection of the Museum of Natural History in Sibiu. It identifies the species of the nymphalid family in six of the museum’s lepidoptera collections. These collections are of extraordinary interest not least because they are associated with natural scientists of European renown, such as Daniel Czekelius, Eugen Worell, Viktor Weindel, Rolf Weirauch, Heinrich Hann von Hannenheim and Eckbert Schneider. The analysis, cataloguing, centralisation and updating of the nomenclature resulted in a number of 1,865 specimens from 49 species and fifteen genera (of the 90 referenced in Romania’s fauna): Aglais, Apatura, Araschnia, Argynnis, Brenthis, Boloria, Euphydryas, Inachis, Issoria, Libythea, Limenitis, Melitaea, Neptis, Nymphalis and Polygonia. Data published in a previous article add 101 specimens from the Vanessa genus. New information Most species originate regionally from the nine counties of Transylvania followed by Oltenia and Moldova (three counties each), Banat and Dobrogea (two counties each), Crișana, Satu Mare and Muntenia (one county each) and the capital of Romania, Bucharest. The species presented in this paper also include the extinct taxon Polygoniaegea (Cramer, 1775), Eugen Worrell collection and three species that are endemic to Romania: Melitaearetyezatica Diöszeghy, 1930, Argynnispandoradacica Hormuzaki, 1892, Daniel Czekelius collection and Boloriapales ([Denis & Schiffermüller], 1775) carpathomeridionalis Crosson et Popescu-Gorj, 1963, both in the Viktor Weindel collection.


Introduction
Tracing the historical evolution of butterflies from the nymphalid family requires updating the information on the species' long-term collection. Updating this information allows ascertaining in how far environmental and anthropogenic factors (Fox et al. 2019, Choi et al. 2021) have determined the temporal and spatial abundance and dominance of these species (Ștefanescu et al. 2021). In Romania, as in other European countries, the entomological material held at natural history museums is a valuable resource for researching declining or extinct populations of butterflies. In museums in Romania, data on butterfly species belonging to the nymphalid family have been collected over time from the whole country and the world and have been obtained through exchanges between specialists or from collectors. The data pertaining to specimens of the nymphalid family thus offer information about the collection sites (Popescu-Gorj 1960, Popescu-Gorj and Drăhia 1964, Ciochia and Barbu 1980, Capușe and Kovács 1987, Burnaz 2002, Marcu and Rákosy 2002, Stănescu 2005, Chimișliu 2006, Chimișliu 2010, Chimișliu 2011, Chimișliu 2012. Since the 19 century, fauna research in Transylvania has been indebted to the work of numerous professional and amateur entomologists with great love for nature. The following natural scientists founded the collections studied in this paper and analysed and determined the preserved material, thus bringing an important contribution to lepidopterological research: Daniel Czekelius (1856-1938; Arnold Müller (1884( -1937; Eugen Worell (1884-1961, Sibiu), Viktor Weindel (1887-1966; Heinrich Hann von Hannenheim (1895-1971, Sibiu), Rolf Weirauch (1906-1984, Alexei Alexinschi (1899( -1966; Hans Rebel (1861( -1940; László th Diószeghy (1877( -1942; Aurelian Popescu-Gorj (1914-1997 and Eckbert Schneider (1927) (Szèkely 2008). The Natural History Museum opened to the public in 1895. Owing to its priceless holdings, the Museum can be currently considered as an archive of lepidoptera biodiversity in Transylvania. It, therefore, plays a significant role in Romanian and European entomological research.
The Museum was founded by German-speaking Transylvanian-Saxon entomologists who collected material in the city of Sibiu, its surroundings, neighbouring regions and other Transylvanian locations (Czekelius 1897, Czekelius 1898, Worell 1951, Székely 1996, Székely 2003, Székely 2004, as well as in other geographical regions of Romania. Throughout time, several generations of natural scientists have evaluated and continue to evaluate the data held in these collections (Caradja 1931, Niculescu 1965, Schneider 1984, Chimișliu 1989, Schneider 1996, Rákosy et al. 2003

Materials and methods
The material evaluated in this paper consists of specimens collected in Romania's eight regions between 1887 and 1984. The analysis has also identified specimens collected in Austria, Germany, Croatia, Switzerland, the Republic of Moldova and Serbia. The species' nomenclature was reviewed by using the actual identification keys as following (Rákosy et al. 2003, Szèkely 2008, Rákosy 2013, Rákosy et al. 2021 in conformity with the Fauna Europaea taxonomic system (Lampert 1923, Karsholt and Razowski 1996, Van Swaay and Warren 1999, Rakosy and Goia 2021. Each species is listed, indicating the examined material, collecting data (in the chronological order of years, months and days), number of specimens, collection sites (including the Romanian county and region), the conservation status (Rákosy et al. 2021) and name of the collector. Question marks are used in cases where information is missing, incomplete or the writing could not be deciphered. All data originate from museum labels; Romanian place names originally listed in German have been replaced with contemporary Romanian ones.

Discussion
The analysis of the six collections of lepidoptera under scrutiny in this article focused on 1,865 specimens collected between 1887 and 1984 and identified 49 species and subspecies of the 90 mentioned in Romania's fauna (Rákosy 2013, Rakosy andGoia 2021). Earlier data regarding the Vanessa genus are based on 101 specimens, 52 specimens of V. atalanta and 49 specimens of V. cardui ( Stancă-Moise 2022). The species' listing for each collection (Fig. 1) includes the following results: Daniel Czekelius's collection, with 271 specimens, 14 genera and 49 (Table 1), Eugen Worrell's collection, 11 genera and 41 species (Table 2), Viktor Weindel's collection, 14 genera and 40 species (Table 3), Heinrich Hann von Hannenheim's collection, 11 genera, 19 species (Table 4), Rolf Weyrauch's collection, 11 genera and 28 species (Table 5) and Eckbert Schneider's collection with 14 genera and 30 species (       Table 1 Daniel Czekelius's collection of lepidoptera is the oldest with specimens collected between 1887 and 1934 in the regions SM and TR, Sibiu County and nearby locations. This collection consists of 14 genera and 49 species represented by a number of 271 specimens (Fig. 1) and is, thus, the most complex collection regarding the species' biodiversity (Table 1). This collection also includes an endemic species, Melitaea retyezatica Diöszeghy, 1930 from Melitaea athalia (Rottemburg, 1775), represented by twenty-six specimens collected by László Diószeghy in the Retezat Mountains (Southern Carpathians) between 1919 and 1922. The species in this collection represent the following conservation status: 18 taxa VU-36.,74%, 18 taxa NT-36.74%, six tax LC-12.24%, four taxa EN-8.16%, two taxa CR-4.08% and one endemic taxon, 2.04%.
The fewest specimens are found in Heinrich Hann von Hannenheim's collection consisting of 117 specimens distributed in 11 genera and 19 species (Fig. 1). The oldest specimen is Brentis hecates ([Denis & Schiffermüller], 1775) collected in 1928. The species were collected in BT, DB and TR and were determined by the collector himself whose name can be found on all labels. Conservation status is as follows: nine species VU-47.37%, six species NT-31.58% and four species LC-21.05% (Table 4).
Rolf Weihrauch's collection contains 258 specimens distributed in 11 genera and 28 species (Figure 1) collected from 1922 to 1978. The oldest specimen is Euphydryas orientalis (Herrich-Schaffer, [1851]) sin. Euphydryas aurinia (Rottemburg, 1775) collected in 1922. The information on the labels is unreadable. The species were collected in BT, DB, OT, MD, MT and TR from the Southern Carpathians, as well as in Austria. All species were determined by the collector whose name appears on all labels. The analysis of their endangerment level is as follows: three taxa CR-10.7%, two taxa EN-7.14%, 11 taxa VU-39.28%, 10 taxa NT-35.73% and two taxa LC-7.14% (Table 5). The newest is Eckbert Schneider's collection. It contains 440 specimens of 14 genera and 30 species (Fig. 1) collected between 1949 and 1984 in BT, CR, DB, OT, MD and TR, as well as the Western Carpathians. The oldest specimen was collected in 1949 and is the only Lybitea celsis (Laicharting, 1782) species held by the Museum. The endangerment level of the collection's specimens is as follows: three specimens EN-10%, 10 specimens VU-33.33%, 12 specimens NT-40% and five specimens LC-16.67% (Table 6).
We present data pertaining to genus diversity, species and existing specimen number present in each collection (Fig. 1). The oldest collection (DC) displays the highest diversity of species. This collection contains 14 genera and 49 species. It is followed in chronological order by EW with 42 species and VW with 40, confirming that, at that time, natural scientists were interested in learning more about and studying the biodiversity of butterflies in SB, the neighbouring localities, as well as in other TR sites and Romanian regions. The species from the more recent collections (HH and RW) contain a lesser number of genera and species, but include more specimens from the DB region. The newest collection (ES) re-confirms the presence of 30 butterfly species of the Nymphalid family captured in six Romanian regions (TR, BT, CR, MD, DB and OT) that are also represented by the largest number of collected specimens.
To facilitate national and international comparison, we present data referring to the distribution of species onsidering the IUCN conservation categories in Fig. 2 (Rákosy 2013, The distribution of species from the collections by IUCN categories. Rakosy and Goia 2021), revealing that the majority of the species of all six collections are potentially endangered taxa (NT) followed by non-endangered (LC), vulnerable (VU), critically endangered (EN) extinct (EX) and endemic taxa.
By synthesising the data referring to the six lepidoptera collections (DC, EW, VW, RW, HH and ES), we identified 157 sites where the butterflies of the nymphalid family were collected between 1887 and 1984. The species were collected in all of Romania's eight regions, from 23 counties and the capital of Bucharest, i.e. on 56.1% of Romania's territory. I designed a map based on these data that reflects the distribution of species in eight regions whose counties are listed by collector:  The species collected in other European countries (Austria, Croatia, Switzerland, Germany, the Republic of Moldova and Serbia) were also graphically represented in Fig. 5.

Conclusions
Romania's territory has a surface of 237,500 km that comprises a variety of geographic forms, from Alpine meadows to the Danube Delta's hydrological profile. They are populated by a diverse fauna of lepidoptera containing over 200 diurnal butterfly species. Romania's South, especially the South-East and South-West (BT and DB) is the region with the highest diversity of lepidoptera in the country (Szèkely 2008) and, at the same time, the northern limit of the distribution of their Balkan species in Europe (Ștefanescu et al. 2013(Ștefanescu et al. , Wildman et al. 2022. The Danube's gorge connects the Carpathian and Balkan Mountains. This geological formation has facilitated the entry of Balkan-type mountainoussubalpine elements into Romania, as far as the Retezat Mountains, for instance Melitaea retyezatica Diöszeghy, 1930. Given that the Carpathian Mountains do not exceed 2,500 m in height, their butterfly fauna is characterised mostly by subalpine, boreo-alpine and boreo-montane species (Szèkely 2008). Most endemic species have formed in the isolated, high regions of the Carpathian Mountains. They were analysed and included in 2 Figure 4.
Geographical representation of Romania and the sites of collectors (red bullet -represents RW, blue bullet -represents HH, yellow bullet -represents DC, brown bullet -represents VW, green bullet -represents ES and pink bullet -represents EW). The article illustrates the biodiversity of the nymphalid family and their historical evolution in Romania and Europe, thus bringing an important historical, scientific and biogeographic "Council Directive (1992)" contribution to the study of butterflies. With the earliest data from 1887, my research complements current research on the presence, diversity and distribution of the nymphalid family in Romania until 1984. Alongside other rare, extinct or endangered species, the presence of nymphalid species with various endangerment levels in the patrimony of the Natural History Museum Sibiu enhances the scientific value of the museum's collections and confirms their significance for ascertaining the biodiversity and distribution of the species throughout time. Future research will include digitising the Museum's butterfly collection to facilitate the access to the collected specimens for specialists searching for historical data on the species.