Introduction
Galichitsa Mt is situated between the lakes Ohrid and Prespa. It is a long, narrow mountain, extending in a North-South direction, continuing in Albania Southwardly. The side of the mountain facing Ohrid Lake is steep, rocky and to a great extent bare, thus resembling the mountains of the Dinaric Alps. This, and the presence of associated dry valleys, makes this part of Galichitsa difficult to access. The opposite, eastern side of Galichitsa, however, is quite different, with slant slopes completely overgrown with forests that go down to the Prespa Valley. Regarding its morphogenesis, the origin of Galichitsa is related to radial tectonic movements that took place in the Tertiary period, when this mountain massif actually developed. The geological structure is mainly limestone. Erosion of the karstic material has left deep traces in the rock, forming all kinds of relief: crevices, hollows, depressions and karstic fields. From a geological standpoint, the island “Golem Grad” situated in Lake Prespa, also belongs to the Galichitsa Mountain, which was split in the past by tectonic movements (Reed et al. 2004) (Figs 1, 2, 3).
The first reports for the spider fauna of Galichitsa Mt. came from Drensky (1929), Drensky (1936) and Stojićević (1929). This information was summarized later by Drensky (1936), who reported 83 species. Additional data can be found again in the papers of Šilhavý (1944), Nikolić and Polenec (1981), Deeleman-Reinhold and Deeleman (1988), Deltshev et al. (2000), Lazarov (2004), Wunderlich (1973) and Wunderlich (1985). All these data are summarized by Blagoev (2002). The aim of this study is to present a review of the spider fauna of Galichitsa Mt. due to critical incorporation of available literature data and unpublished faunistic records carried out by sporadic research in the last 10 years.
Materials and methods
The spider material treated herein comes from two major sources. The first part comprises critical incorporation of all available literature records concerning the distribution of spiders of Galichitsa Mt. The second part comprises original collections made in the last 10 years during field surveys covering most of the territory of the mountain (Fig. 4, Table 1). The spiders have been collected mainly by hand, under stones, by sweeping and sewing (Figs 5, 6, 7). The names of the collectors: P. Beron (P.B.), G. Blagoev (G.B.), C. Deltshev (C.D.), M. Komnenov (M.K.), S. Lazarov (S.L.), B. Petrov (B.P.), E. Stojkoska (E.S.). and D. Vidincheva (D.V.) are mentioned by their abbreviations in Table 1. The taxonomic arrangements of the species list follow Platnick (2013). The material is deposited in the Natural History Museum (Skopje) and National Museum of Natural History (Sofia).
Analysis
Species composition
A total of 294 species of spiders from 31 families have been found in Galichitsa Mt. New for the mountain are 85 species, 20 of them are also new to the spider fauna of FYR of Macedonia. High species richness was recorded for 5 of the families: Linyphiidae – 40 species, Lycosidae – 37 species, Gnaphosidae – 31 species, Araneidae – 27, and Theridiidae – 24 species (Table 2). The degree of exploration of the group in the mountain is about 60%. The number of the species of Galichitsa Mt is high and represents about 45% of the spider fauna of the country (Blagoev 2002). This is also evident from a comparison with the number of spiders reported from the other mountains in the Balkan Peninsula: West Rhodopes – 418 (38%) Deltshev et al. 2011), Pirin – 324 (30%) (Deltshev and Blagoev 1997), Rila – 280 (26%) (Deltshev et al. 2000a), Central Stara Planina – 270 (25%) (Deltshev et al. 2000b).
Zoogeographical analysis
According to their current distribution the established 294 species can be classified into 16 zoogeographic categories, grouped into 5 chorological complexes (Cosmopolitan; Holarctic; European; Mediterranean; Endemic) (Table 3, Fig. 10). The data concerning the general distribution and the chorological characteristics of spiders are taken from Helsdingen (2012), Platnick (2013) and Taglianti et al. (1999).
Cosmopolitan species complex
Cosmopolitan species complex (COS + SCO) includes only 6 (2%) species widespread in Europe. While the species Pholcus phalangioides, Parasteatoda tepidariorum, Steatoda triangulosa, and Tegenaria domestica are connected with human buildings, Prinerigone vagans can be accepted as a mountain element. The species is well represented in the woodlands and high altitude zones of the mountains. Tetragnatha nitens was reported from the Galichitsa Mt by Drensky (1929), and there is no new data on its distribution in the mountain.
Holarctic species complex
Holarctic species complex (H + P + WP + ECA) is best represented and comprises 196 (66.7%) species. The Palearctic species s. l. are dominant (125 species, 42.5%), followed by Holarctic (44 species, 15%); Europeo-Central Asiatic (18 species, 6.1%) and West Palearctic (9 species, 3.1%).
This complex includes especially widespread species associated with lowlands, woodlands and high altitude zones of mountains. Most of the species are well represented in the mountains. Characteristic mountain elements are Frontinelina frutetorum, Gongilidium rufipes, Pityohyphantes phrygianus, Tenuiphantes tenuis, Trichoncus affinis, Drassodes lapidosus, Haplodrassus signifer. Some xenotopic species are widely distributed in the mountains and reach the highest summits as aeronauts (Thaler 1986). Meioneta rurestris and Oedothorax agrestis, which inhabit the mountain zone in dense populations, also belong to this complex.
European species complex
European species complex (E + MSEE + EE + SEE) comprises 49 (16.7%) species. The European species s. l. are dominant (39 species, 13.3%), followed by Southeast European (5 species, 1.7%), Middle and Southeast European (2 species, 0.7%), and East European (3 species, 1.0%).
The complex includes widespread species, which inhabit both lowlands and mountains. Мountain elements are the species Pardosa albatula, Inermocoelotes falciger, Inermocoelotes karlinskii, Malthonica ferruginea, Malthonica silvestris, Cybaeus angustiarum, Zelotes apricorum. Meta menardi and Metellina merianae, found only in caves, can also be placed into this complex.
Mediterranean species complex
Mediterranean species complex (MCA + M + SE + NM + NEM) includes 24 (8%) species. The Mediterranean species s. l. are dominant (12 species, 4%), followed by North Mediterranean (7 species, 2.4%), North-East Mediterranean and (3 species, 1%) and Mediterranean-Central Asiatic and South European (each by 1 species, 0.3%).
The main part of the established species is presented in the lower and dry parts of the mountain, occurring in the xerothermic oak forests and meadows. Characteristic for the mountain zone are: Tmarus piochardi, Heliophanus kochii, Heliophanus melinus, Macaroeris flavicomis, and Pellenes moreanus.
Endemic species complex
Endemic species complex (BP+GA) comprises 18 (6.2%) species. The group of Balkan endemic species (16 species, 5.5%) comprises mainly mountain elements, such as: Dysdera pectinata, Dysderocrates storkani, Cheiracanthium macedonicum, Zodarion ohridense, Zelotes babunaensis, Xysticus macedonicus and Pellenes moreanus. They are characteristic for forest and subalpine parts of the mountain, while Pachygnatha clerckoides inhabits the coastal vegetation of water basinsin lower parts of the mountain. Centromerus acutidentatus, Lepthyphantes centromeroides, Palliduphantes byzantinus, Palliduphantes spelaeorum, Palliduphantes trnovensis, Tegenaria paragamiani are found only in caves.
The local endemics: Zora prespaensis and Xysticus tenebrosus ohridensis, can be regarded also as mountain elements. They are known from single localities and need additional faunistic and taxonomic studies.