Balkan endemic vascular flora of the Konjuh Mountain Balkanska

This paper presents data on the diversity and distribution of Balkan endemic vascular plants on Konjuh Mo - untain in northeastern Bosnia and Herzegovina. Konjuh is characterized by geological heterogeneity and a si - gnificant proportion of ophiolitic substrate, which supports the development of endemic-relict serpenti - nophytes. A total of 31 endemic and four subendemic taxa were recorded in the surveyed area. Among these, Caryophyllaceae , with five recorded endemic taxa, is the most abundant family. The analysis of life forms and chorological spectra showed a dominance of hemicryptophytes and taxa from the South European and Me - diterranean-Sub-Mediterranean chorological groups. The majority of endemic and relict taxa in the surveyed area are serpentinophytes. A total of 18 recorded taxa are listed as threatened according to the Red List of Flora of the Federation of Bosnia and Herzegovina. The species findings are presented with a distribution map. The distribution range of endemic and endangered taxa in Konjuh extends beyond the protected area. The results provide a list of locations of particular interest for further research and potential protection due to the diversity of endemic taxa.


INTRODUCTION -Uvod
The term "endemism" can be defined in many ways, and in most cases, it refers to the limitation of a species' range to a geographical area, type of ecosystem or habitat, biogeographical region, or a specific country (Nikolić et al., 2015). In the biological context, endemics are taxonomic units (populations, subspecies, species, genera) whose distribution is restricted to a certain area (Šilić, 1990). Depending on the size of their range, endemics can be divided into two groups: subendemic, or endemics in a broader sense, which inhabit larger geographical areas (e.g., the entire Balkan Peninsula), and steno-endemics, or endemics in the narrower sense, which are distributed in smaller areas (individual mountains, canyons, island groups, a single country). Additionally, the term "local endemics" is used to describe taxa limited to a narrow area of up to several hectares. The definition of Balkan endemic species has remained unchanged since Turill (1929), who defined them as species with a range limited to the Balkan Peninsula (Tomović et al., 2014). According to the available data, the vascular flora of the Balkan Peninsula contains approximately 8000 taxa, including 2600-2700 endemic taxa at the species or subspecies level (Stevanović, 2005).
The unique processes of forming the geological base, soil types, relief, ecoclimate, and water regime in the past have led to the development of a unique flora in the Dinarides of Bosnia and Herzegovina. It is characterized by the presence of numerous paleo-and neo-endemics, as well as tertiary and glacial relics that survived in refugia such as gorges, canyons, and mountain cirques. The first National report for the Convention on Biodiversity (Redžić et al., 2008) states that the flora of Bosnia and Herzegovina contains 450 endemics, which is one-tenth of the total number of vascular taxa registered in the country. According to Lubarda et al. (2014;2019), the flora of Bosnia and Herzegovina contains 309 Balkan endemic taxa at the species and subspecies level, classified into five chorological groups.
The first extensive floristic research of Konjuh was conducted in the western part of the mountain by Ritter-Studnička (1958;1963;1970) as part of a broader study of the serpentine flora and continued for the purpose of an exhaustive study of genome size in plants growing on serpentine (Pustahija et al., 2013). The diversity of algae and aquatic plants in crenic communities of the Konjuh Mountain was described by Kamberović (2015;2020) and Kamberović et al. (2019). Several endangered and endemic taxa were listed in the paper on the diversity of Paučko Lake . Recent publications include remarks on the distribution of endemic plants Polygonum albanicum (Maslo and Šarić, 2021) and Euphorbia serpentini (Maslo et al., 2022), as well as data on the distribution of the threatened species Adenophora liliifolia (Ballian and Šarić, 2015).
A part of Konjuh Mountain is legally protected as a fifth-category protected area -a Protected Landscape, and recent biological surveys have mainly focused on this area. A study conducted by a group of authors contracted by "Enova'' in 2017, in order to create a baseline of the state of biodiversity of the Konjuh Protected Landscape, lists a total of 11 endemics and 10 sub-endemics out of a total of 326 plant taxa registered in the area of the Protected Landscape. Additionally, a study on species and ecosystem diversity in the Protected Landscape Konjuh, published as part of a project realized by the non-governmental organization CISP (2019), lists about 500 plant taxa but excludes the endemism analysis.
The aim of this paper is to survey and present qualitative data on the taxonomy, distribution, chorological groups, floristic elements, and conservation status of Balkan endemic plant taxa in the entire area of Konjuh Mountain, including parts outside of the present Protected Landscape for which recent data were not available.

Study area
The Konjuh Mountain is part of the central Dinarides. It is located between northeastern and central Bosnia and is topographically classified as a hilly-mountainous area, with absolute altitudes ranging from 300 to 1326 m a.s.l. (Ristić et al., 1967). The geological structure consists of a complex of magmatic, metamorphic, and sedimentary formations. Konjuh is part of a large ultrabasic massif, the Krivaja-Konjuh ophiolite complex, which is one of the largest complexes in the Dinaric ophiolite zone. Ultramafic rocks (ultrabasic, serpentine, peridotite) predominate in the geological structure of Konjuh Mountain, especially in the west and northwest. The central parts of the mountain consist of igneous rocks, mostly diabase, and the eastern part is mostly composed of sedimentary rocks of Middle Triassic limestone. An undissociated formation of ophiolitic mélange is found along the eastern and southern parts of the Konjuh peridotite-serpentine massif. It includes various clays (sometimes schistose), sandstones, less often conglomerates, marls, marly limestones, and cherts (Babajić, 2009

Species identification and data analysis
The plant taxa were identified according to Tutin et al. (1964Tutin et al. ( -1993 and Nikolić (2020a;2020b). Taxonomic status was determined according to the Euro+Med database (http://ww2.bgbm.org/EuroPlusMed/). The endemic status was assigned based on the lists of endemic taxa (Šilić, 1990;Lubarda et al., 2014;Lubarda, 2019). The assessment of the conservation status was done according to the Red List of wild species and subspecies of plants, animals, and fungi of the Federation of Bosnia and Herzegovina (Official Gazette of the Federation of Bosnia and Herzegovina, 07/14; Đug et al., 2013), and the IUCN Red List of Threatened Species (IUCN, 2022). The analysis of the presence of protected taxa was done according to the list from the Rulebook on Protection Measures for Strictly Protected Species and Subspecies (Official Gazette of the Federation of Bosnia and Herzegovina, 21/2020). The relict status was assigned according to Stevanović et al. (2003). The data on floral elements and chorological groups were determined according to Lubarda et al. (2014), and the data on life forms according to Raunkiaer (1934) from Mueller-Dombois & Ellenberg (1974) and Stevanović (1992). Digital photographs were taken for each taxon in the field.
The distribution of the taxa is presented on the map using a standard UTM 10×10 km grid based on the Military Grid Reference System (MGRS) projection (Lampinen, 2001) in zones 33T and 34T. The distribution map of endemic taxa was created using QGIS software version 3.4, based on OSM (https://www.openstreetmap.org). ). The distribution of these taxa extends across a wider area of South-Eastern Europe and therefore they are not included in the list.

Rezultati i diskusija
Caryophyllaceae is the most abundant family with 5 taxa, followed by Boraginaceae with 3 taxa (Graph 1). Genera Sesleria, Euphorbia, Knautia, and Cerastium are represented by two taxa each, while all other genera are represented by only one taxon.     (Figure 3).  The life form analysis of endemic plant taxa shows the domination of hemicryptophytes (14 taxa, 45%) and chamaephytes (9 taxa, 29%), which is in accordance with the data on the endemic flora of Central Serbia, Kosovo, and Montenegro (Tomović et al., 2014;Vuksanović et al., 2016;Halilaj et al., 2021). Therophytes are more numerous than geophytes, while endemic phanerophytes include only one taxon -Cytisus austriacus var. maezius (Graph 3).   haynaldii has been found on three locations (Olovski krševi, Brateljevići i Sokolina), whilst P. alba subsp. acaulis inhabits two locations Olovo and Sokolina. Both species are associated with exposed carbonate habitats. S. canina subsp. tristis has been identified exclusively in serpentine habitats in several locations (Varda, Careva Ćuprija, Buk, Grgići). The endemic plant richness of Konjuh, which includes 31 endemic taxa and four subendemic taxa, is not negligible in comparison with the high Dinaric mountains (Bjelčić et al., 1969;Bjelčić & Šilić, 1971;Lakušić & Redžić, 1989;Šilić & Abadžić, 1986Šilić & Abadžić, , 1991Stevanović, 1996), considering the overall height of the mountain and its geographical position. After analyzing and synthesizing the previous results on Balkan endemic flora in Bosnia and Herzegovina, published by numerous botanists over the last 150 years, Lubarda et al. (2014) (Stevanović et al., 2003). Identified taxa Polygonum albanicum, Gypsophila spergulifolia, Fumana bonapartei, Halacsya sendtneri, and S. canina subsp. tristis are transregional serpentine Balkan endemics, distributed in the wider serpentine areas in the Balkans. The genus Halacsya, with the only species H. sendtneri, is a monotypic endemic-relict genus found in the investigated area. It occurs in well-developed populations and is numerous on exposed ophiolite substrates.
In the group of regional serpentine endemic taxa restricted to a single floristic subregion or province, the species Sesleria serbica has been identified. This species is typical for Central and Eastern Bosnia and Serbia (Stevanović et al., 2003). The area of Konjuh Mountain is considered to be the northernmost distribution point of endemic serpentinophytes in the Balkans for locally distributed serpentinophytes: Centaurea nigrescens subsp. smoliensis, Euphorbia gregersenii, and Cytisus austriacus var. maezius (Stevanović et al., 2003). The taxon Cytisus austriacus var. maezius is listed as Chamaecytisus maezeius K. Malý in Lubarda et al. (2014) and Stevanović et al. (2003), but according to Pifkó (2015), the name Chamaecytisus maezeius in these papers is mistakenly used, since this combination has never been validly published. In addition to the above-mentioned local endemics, Viola beckiana can also be classified in the stenoendemic group according to the First Report for the Convention on Biodiversity of Bosnia and Herzegovina (Redžić et al., 2008). The locus classicus for the description of this species is on Smolin (which is included in this research), and according to the aggregated distribution data presented by Đug et al. (2013) does not fit into the sub-endemic term applied in this study. We did note the presence of Cytisus procumbens in the surveyed area, which is morphologically quite similar to the endemic C. pseudoprocumbens, but the presence of the endemic species C. pseudoprocumbens was not confirmed.
Euphorbia montenegrina (Bald.) K. Malý was also mentioned as an endemic plant in earlier studies of this region (Public Institution Protected Landscape Konjuh, 2017), but its presence was not confirmed during our research. A recently published work on the distribution of Euphorbia serpenini in the area of Konjuh (Maslo et al., 2022) indicates the frequent confusion of these two species in the literature. According to the above-mentioned authors, E. serpentini was mistakenly referred to as E. montenegrina in surveys of serpentine sites in Bosnia and Herzegovina and on Konjuh in many cases, despite the different ecology of E. montenegrina, which prefers the alpine and subalpine habitats and limestone substrate, unlike the obligate serpentinophyte E. serpentini.
Recent studies on biodiversity have mostly focused on the Protected Landscape area. Our research indicates the presence of numerous endemic species outside the boundaries of the Protected Landscape, especially in the southwest area of Mt. Konjuh on the ophiolite bedrock and limestone habitats around Olovo, Sokolina, and the Drinjača River. The process of declaring protected areas in the Federation of Bosnia and Herzegovina below the second level of protection is given to the cantonal government. Since Konjuh mountain is the border of the canton, this area is only partially protected. According to the Federation's plans for B&H, the entire area is designated as a potential Natura 2000 habitat, which would certainly be a solution for the long-term preservation of species and ecosystems in this area.

CONCLUSIONS -Zaključak
The flora of Konjuh Mountain includes 31 endemic and four subendemic taxa. The largest number of endemic taxa occurs on the ophiolite substratum and consists of endemic-relict forms of serpentinophytes. The chorological spectrum is characterized by the dominance of South-European and Mediterranean-Sub-Mediterranean taxa.
A total of 18 identified endemic taxa are classified as threatened. The presence of strictly protected, critically endangered endemic-relict serpentinophytes such as Fumana bonapartei indicates the importance of Konjuh Mountain for the preservation of this and other stenoendemic and relict taxa. Most endemic taxa also inhabit areas outside of the Protected Landscape, particularly serpentine habitats that gravitate toward the Krivaja River basin and exposed limestone habitats. The results of this study can be useful in the preparation of studies for the integrative protection of this area as a Natura 2000 site, regardless of cantonal borders.