Catalogue of the ants (Hymenoptera, Formicidae) of Bulgaria

Abstract The present catalogue of the ants (Hymenoptera, Formicidae) of Bulgaria is made on a base of critical reconsideration of literature (covering the period from 1892 till 2009 and part of 2010) as well as on examination of the authors‘ and several museum‘s collections. A lot of data were omitted in the previous Bulgarian monograph on ants, lots of new data were recently added and many important additions and alterations were made due to taxonomic revisions of Eurasian Formicidae during the last three decades. Two new species are reported for the country [Temnothorax graecus (Forel, 1911) and Temnothorax cf. korbi (Emery, 1924)]. This catalogue contains a list of 163 ant species belonging to 40 genera of 6 subfamilies now known from Bulgaria. Synonyms and information on the previously reported names in relevant publications are given. Known localities of the species are grouped by geographic regions. Maps with concrete localities or regions for each species were prepared. The conservation status of 13 ant species is given as they are included in IUCN Red List of Threatened Species and Bulgarian Biodiversity Act. In comparison with adjacent Balkan regions the ant fauna of Bulgaria is quite rich and its core is composed of South European elements.


Introduction
Th e Bulgarian myrmecofauna is among the richest of the local faunas of Southern Europe. Th is is a result of the high diversity of natural habitats, variability of climate and orography, and by the complicated history of the origin of the ant fauna of this relatively small territory. Despite a comparatively large number of publications concerning myrmecological investigation in this country, including monographic synthesizing, a lot of data has been omitted by previous authors and much new data has been added recently. To make a complete synopsis of all the existing information we have summarized it and compiled modern Catalogue of Bulgarian ants.
Early studies of the myrmecofauna of Bulgaria started more than 100 years ago, when Auguste Forel (1892) recorded 54 ant species from various regions of the country: the city of Sofi a, Rila Mountain, Rhodopi Mountains, Stara Planina Mountains, and South Black Sea coast. Th ree new species were also described in this paper: Temnothorax bulgaricus (as Leptothorax), Cardiocondyla bulgarica (as Cardiocondyla elegans Emery var. bulgarica), and Cardiocondyla stambuloffi i.
Th e most signifi cant contribution to the fauna and biology of the ants in Bulgaria over the past century was made by Dr. Neno Atanassov, whose fi rst papers were published in the 1930s , where he reported 57 species. After World War II his monographic work on the fauna and biology of ants of the Vitosha Mountain was published . A couple of other faunistic papers for the Bulgarian territory (Atanassov and Vasileva 1976), particularly of South Dobrudzha (Atanassov and Bulgurkov 1955), Petrich basin , Lozenska Planina Mountain (Vasilev and Evtimov 1973), Rachene river valley (Vasilev 1984) made important additions to our knowledge of the Bulgarian myrmecofauna. Further contributions were also provided by Wesselinoff ( , 1968Wesselinoff ( , 1972, Atanassov (1957Atanassov ( , 1965, Urbański (1975), Baroni Urbani (1977.
In the 1960s and 1980s myrmecological investigations in Bulgaria were concerned mostly with the distribution and biology of red wood ants , Ronketi and Penev 1966, Keremidchiev et al. 1971, Gateva 1974, Vatov and Bobev 1976.
Over the last three decades many important additions and alterations to the taxonomy of Eurasian Formicidae, that also include data on Bulgarian ants, have been published (Seifert 1983, 1988a, b, 1990, 1996, b, 2000a, b, c, 2002a, b, 2003a, b, 2005, Radchenko 1989, 1995a, b, 1997a, b, 2000, 2001, Radchenko and Elmes 2003, Schlick-Steiner et al. 2003, 2006a, Seifert and Schultz 2009). Two new species have been described from the territory of the country: Lasius balcanicus Seifert, 1988 and Lasius nitidigaster Seifert, 1996. Th e fi rst attempt to summarize data on Balkan ants, including the Bulgarian fauna, was made by Agosti and Collingwood (1987a, b). Th ey reported 112 species for Bulgaria based on data from their own and some other Museum collections, as well as on literature data. However, much of the data from these two papers needs revision and correction.
As a result, we now include in the List of Bulgarian fauna 163 ant species belonging to 40 genera of 6 subfamilies.

Materials and order of the Catalogue
Th e Catalogue we present here is based on the investigation of ants collected personally by the authors in various regions of Bulgaria during last decade, as well as on the material, preserved in the following Museums and Institutions: private collection of A. Lapeva-Gjonova, Faculty of Biology, Sofi a University; private collection of V. Antonova, Institute of Biodiversity and Ecosystem Researches, Bulgarian Academy of Sciences, Sofi a (IBER); Zoological Museum of the Moscow State University, Russia (ZMMU); Museum and Institute of Zoology of Polish Academy of Sciences, Warsaw, Poland (MIZ); Shmalhausen Institute of Zoology of Ukrainian National Academy of Sciences, Kiev, Ukraine (SIZK); National Museum of Natural History, Prague, Czech Republic (NMNHP). All the available literature was also surveyed and the data therein used and in some cases critically reviewed.
Dr. Neno Atanassov's collection of ants is kept in the National History Museum in Sofi a and includes a few thousands of mounted specimens. Unfortunately, the collection is almost useless as the specimens have no locality labels but only numbers.
Th is catalogue contains a list of ant species, currently known in Bulgaria. Synonyms, information on the previously reported names and localities are included. Two new species [ Temnothorax graecus  and Temnothorax cf. korbi (Emery, 1924)] for the country are reported.
Th e arrangement of genera in the subfamilies in the catalog is given by tribes. Th e species within each genus are listed in alphabetical order. Actual names of genera and species, and their authors are consistent with the most recent world catalogues of ants (Bolton 2003, Bolton et al. 2006 or, in the case of subsequent publications, with the most recent publications of the relevant authors. Publications by both Bulgarian and foreign authors concerning Bulgarian ants covering the period from 1892 till 2009 (2010, part) have been considered. After the actual name of the species, a list of synonyms and names used in relevant publications is given. Known localities of the species are grouped by geographic regions and subregions, arranged in the order given by Hubenov (1997) (Map 1). We have introduced additional regions and/or subregions for localities, which are not adequately covered by that classifi cation system. Some of the localities, given in the references with obsolete names in older references, have been updated here. A few of the names could not be associated with any city or geographical location in the country due to typographical errors or incorrect transliteration. We have cited them in an italic font in the text. Publications without any reference to particular localities in the country are included before all other localities as referring generally to Bulgaria. Notes with comments on taxonomic position and distribution are added for some species.
IUCN species categories are given by the last "1994 Red List Categories & Criteria (version 2.3)" (IUCN 2009). It incorporates changes as a result of comments from IUCN members and was adopted by the IUCN Council in December 1994. In the recent catalogue the global status category for a given taxon is included. Th e national status of all the species recorded from Bulgaria that are listed in the IUCN report need updating.
Maps with concrete localities or regions for each species have been prepared. Whenever the number of localities for a species is very low, the information for two or more species is combined on a common map. In some cases species have been reported without a specifi c locality and only region or subregion were noted. In these cases the species are assigned to the whole area (region or subregion).

Myrmica slovaca
Despite the fact that one of the type localities of M. slovaca is in Bulgaria, this species was omitted by Atanassov and Dlusskij (1992).
Notes: After examination of the "holotype" of M. bessarabica Seifert (2002a) found that there is a discrepancy between Nasonov's original description and the characteristics of this specimen, and proposed considering M. bessarabica incertae sedis in the genus Myrmica, and revived the name M. specioides from synonymy (see also Radchenko and Elmes 2004).
Notes: According to Atanassov and Dlusskij (1992) the records of Forel (1892) and  for Crematogaster scutellaris should be refer to Crematogaster schmidti.
Notes: Th is species was omitted by Atanassov and Dlusskij (1992).

Genus Temnothorax Mayr, 1861
Notes: Till recently Temnothorax was considered as a junior synonym of Leptothorax, but Bolton (2003) has divided the latter genus to two: Leptothorax (which includes the former subgenus Leptothorax s. str.) and Temnothorax (which includes, among others, the former subgenus Myrafant M. R. Smith). Th erefore all authors before 2003 and some after this date have placed Temnothorax species in the genus Leptothorax (except of T. recedens).

Temnothorax corticalis (Schenck, 1852)
Records (Map 30): Bulgaria (Agosti and Collingwood 1987a); Vitosha Mt.: Dragalevtsi monastery (Atanassov and Dlusskij 1992); Krupnik-Sandanski-Petrich Valley: west of Petrich, along Strumeshnitsa river , Atanassov and Dlusskij 1992; Northern Black Sea coast: Balchik (Atanassov and Dlusskij 1992); Southern Black Sea coast: Tsarevo (Atanassov and Dlusskij 1992).  [Seifert 1995 (as Leptothorax nylanderi slavonicus)]. Notes: For many years T. crassispinus was considered as a junior synonym of T. nylanderi, but Radchenko (2000) showed that it is a good species, distributed mainly in the Eastern Europe including Bulgaria, while T. nylanderi is mainly West European species. Nevertheless, we recently found T. nylanderi in parks in Sofi a. Th erefore although most of the records of T. nylanderi for Bulgaria from before 2000 should be T. crassispinus, some of them might include also "true" T. nylanderi, this question may be defi nitely resolved only after investigation of the correspondent material.
Notes: Bolton (1995) and Bolton et al. (2006) erroneously considered T. melanocephalus as a junior synonym of T. tuberum, referring this synonymy to Casevitz-Weulersse (1990), but at the same time noted that Atanassov and Dlusskij (1992) considered T. melanocephalus as a good species. Since 1992 its status has not been formally changed by any subsequent authors and we consider it as a good species.
Notes: Th is species was omitted by Atanassov and Dlusskij (1992).

Cardiocondyla nigra Forel, 1905
Records: Bulgaria [Agosti andCollingwood 1987a, Radchenko 1995b (as junior synonym of C. batesii Forel)]. Notes: Agosti and Collingwood (1987a) recorded C. nigra for Bulgaria and Turkey (Th race), and Radchenko (1995b) repeated this record (under the name C. batesii that he considered as a senior synonym of C. nigra). However, Seifert (2003b) regarded C. batesii and C. nigra as separate species. According to him, the fi rst species is distributed in Iberian Peninsula and NW Africa [Agosti and Collingwood (1987a) recorded it also for Greece], and the latter -in the Iberian Peninsula, North Africa and Turkey. Most probably, both species have distributions that include Mediterranean areas and are absent from Bulgaria; their occurrence in this country needs confi rmation.
Notes: Th is species was omitted by Atanassov and Dlusskij (1992).
Notes: C. herculeanus is a boreo-montane species and its record from "Maslen nos" seems doubtful.
Notes: Th is species was omitted by Atanassov and Dlusskij (1992).
Notes: Th is taxon was omitted by Atanassov and Dlusskij (1992). Taxonomic status of this subspecies is not properly resolved and we cannot exclude the possibility that this name is junior synonym of C. nodus. , Vasilev and Evtimov 1973 to C. nodus. Th e fi rst name is now considered as a junior synonym of C. bicolor (Förster) -the species is distributed mostly in North Africa and probably in the Middle East. C. viaticus is defi nitely known from Iberian Peninsula and North Africa. At the same time, in Balkans, lives single species from the bicolor species-group: C. nodus. As the taxonomy of this genus was studied insuffi ciently previously to the last two decades, all old records of C. bicolor and C. viaticus for Bulgaria most probably belong to C. nodus.

Analysis of the faunistic data
Th e current Catalogue was compiled based on the investigation of the available material, including that collected by the authors personally, and on the critical reconsideration of the existing publications concerning Bulgarian ants (more than 100 sources). As a result, we include here 163 ant species, belonging to 40 genera of 6 subfamilies: Subfamily Amblyoponinae -1 genus, 2 species Subfamily Ponerinae -3 genera, 5 species Subfamily Proceratiinae -1 genus, 2 species Subfamily Myrmicinae -21 genera, 77 species Subfamily Dolichoderinae -5 genera, 9 species Subfamily Formicinae -9 genera, 68 species Nevertheless, several records seem doubtful and need confi rmation. On the other hand, we assume that after revision of a couple of genera (e.g. Messor, Tetramorium, Temnothorax, Camponotus, etc.) the number of species might increase. Compared with the "Fauna of Bulgaria" (Atanassov and Dlusskij 1992), this catalog contains 51 more ant species and summarizes the published data for all 163 species, found in Bulgaria.
In the monograph of Atanassov and Dlusskij (1992) 27 species, recorded for Bulgaria before 1992, are missed. Some of them are included as synonyms or they fi gure in the determination keys. Four of them, Proceratium numidicum, Messor concolor, Temnothorax nigriceps and Cardiocondyla nigra, were recorded for Bulgaria without exact localities till 1992. Lasius myops was conidered by Atanassov and Dlusskij (1992) as junior synonym of L. fl avus and believed that previous records of Proformica nasuta for Bulgaria belong to P. striaticeps (see also Notes to P. nasuta in Catalogue). Atanassov and Dlusskij (1992) discussed that it is possible to fi nd some ant species on the Bulgarian territory -T. madeirense (as Tapinoma ambiguum), Crematogaster scutellaris, Lasius distinguendus and Lepisiota splendens (as Acantholepis splendens). Th e last two are included into the determination keys as well.
Th e presence of genera Chalepoxenus, Myrmoxenus and Harpagoxenus in Bulgaria was suggested by Atanassov and Dlusskij (1992), and these three genera are included only into the key for genera.
Finally, we propose to exclude from the Bulgarian myrmecofauna two species, recorded earlier.
Tetramorium meridionale Emery, 1870 was recorded for Vitosha Mt. by . Based on the modern data, this somewhat enigmatic species is distributed in the West Mediterranean region (Iberian, southern France, Italy). It was recorded also for Crimea and even for Ural region (Nasonov 1889, Ruzsky 1905), but these records seem doubtful (see Radchenko 1992a, b, Sanetra et al. 1999. Formica fuscocinerea Forel, 1874 was considered by most authors for many tens of years as a mountain Central European and Balkans subspecies of F. cinerea (e.g. see Dlussky 1967), but Seifert (2002b) considered it as a good species, which is locally distributed in the Alps and Northern Apennines.

Comparative analysis of the ant fauna of the diff erent regions of Bulgaria
We compare ant faunas of the natural regions of Bulgaria, as proposed by Hubenov (1997) (Map 1, Map 76 and Appendix III). Diff erent regions of the country, and even diff erent parts of a single region, have been studied to a variable extent, and there are many places where the ant fauna has been investigated insuffi ciently. Th us, currently we have no possibility to make a proper and detailed comparison of the ant faunas and their similarity across diff erent regions, however our data might be useful for planning further investigations regarding the distribution of ants in Bulgaria.
Th e best studied area is the Rilo-Rhodopi region with 143 species from ca. 120 localities. Th e subregions Middle Struma Valley (line Krupnik-Sandanski-Petrich, 76 species) and Rhodopi Mountains (95 species) are also well studied areas with high species richness.
Despite the fact that the Transitional region is a larger and more diverse topographically, as well as climatically than the Rilo-Rhodopi region, only 115 species are reported from there. Most probably, this is the result of lower level of the myrmecological investigation carried out there. Only Sofi a Basin (62 species), Vitosha (48), Plana (50), Lozenska (40) and Strandzha (40) mountains are suffi ciently studied. Almost all information on myrmecofauna of Vitosha subregion arises from investigations in the following areas (Sofi a Basin, Vitosha and Plana) and accordingly the greatest number of species have been reported there -84. Th e worst studied area is the Kraishte-Konyavo subregion from the Transitional region, where only 19 ant species from just 8 localities are known, and 7 of these localities are in Zemen gorge.
Th e number of ant species recorded from the Stara Planina Range system is similar to that of Transitional region. Th e total number found in both subregions (Predbalkan and Stara Planina) is 88 species, 76 of which are given for Stara Planina Mountains only.
Th e territory of the Black Sea coast region is the smallest among all natural regions of Bulgaria and it is suffi ciently studied: 75 ant species from ca. 27 localities are recorded.
Contrary to this, only 21 species are recorded from the Danubian Plain, which has an area of 31 523 square kilometers.
In general, we may consider that the ant fauna of Bulgaria is quite rich, which is confi rmed by its comparison with adjacent regions.
Th us, 103 ant species from 34 genera are recorded for Romania (Markó et al. 2006), although the authors expect more species will be found in the country in the future. 140 species are known from Slovenia and 129 -from Croatia (Bračko 2006(Bračko , 2007. Th e fauna of Serbia and Montenegro contains totally 160 species, 133 of which are found in Montenegro (Karaman 1998, Petrov 2004; 78 species are known from Macedonia (Dofl ein 1920, Petrov 1994, Karaman 2002). Agosti and Collingwood (1987a) recorded for Th racian part of Turkey 90 species, while more correct data of Çamlitepe and Aktaç (1987) and Aktaç et al. (1994) include 76 species. Finally, Greek and Turkish faunas are estimated at about 300 ant species each (Aktaç 1976, Petrov 2006, Kiran and Aktaç 2006.
Finally, we may conclude: the Bulgarian ant fauna is rich and adequately studied as a whole, while several regions of the country require additional investigations. Such poorly myrmecologically elaborated areas are the Danubian Plain, Th racian Lowland, Kraishte-Konyavo and Tundzha-Strandzha subregions; moreover, ants of the Central Danubian Plain, Ruy, Maleshevska, Zemenska and Vlahina mountains have not been studied at all.
In general, Bulgarian ant fauna is richer than that of Romania, similar by the species number to those of many former Yugoslavian countries, but essentially poorer than faunas of Greece and Turkey. Th is fact is not surprising, regarding the geographical location and landscapes of Bulgaria. Furthermore, the core of Bulgarian myrmecofauna is composed by South European elements, but not Mediterranean species, and it is more closely related to the faunas of northern territories than to Greek fauna.

Conservation status of the species
Totally, 13 ant species found in Bulgaria, are included in IUCN Red List of Th reatened Species. Five of them ( Anergates atratulus, Chalepoxenus muellerianus, Myrmoxenus ravouxi, M. gordiagini and Strongylognathus kratochvili) are placed to the category Vulnerable D2: "Population is characterized by an acute restriction in its area of occupancy (typically less than 100 km 2 ) or in the number of locations". Formicoxenus nitidulus and Harpagoxenus sublaevis are also Vulnerable, but in A2c category: "A reduction of at least 20%, projected or suspected to be met within the next ten years or three generations, whichever is the longer, based on a decline in area of occupancy, extent of occurrence and/or quality of habitat". Th e status of another fi ve species ( Formica aquilonia, F. lugubris, F. polyctena, F. pratensis and F. rufa) is Lower Risk/near threatened: "Taxa which do not qualify for Conservation Dependent, but which are close to qualifying for Vulnerable". Formica rufa is included in the Annex 2 and 3 of the Bulgarian Biodiversity Act (2002) as well (protected on the entire territory of the country). Temnothorax recedens is cited in the category Lower Risk/least concern: "Taxa which do not qualify for Conservation Dependent or Near Th reatened".
Th e IUCN's classifi cations, based on the sizes of geographic ranges or the patterns of habitat occupancy, is complicated by problems of spatial scale. All of the above mentioned species need their conservation status at national level up-dated. We do not have enough data yet about the distributions and populations of these species in Bulgaria or on how their status in Bulgaria relates to their global popula-tion. Further investigations and accurate mapping would supply data that would clarify the situation.  8,9,10,11,12,60,61,70,82,83,84,117,118