ANN ALES • Ser. hist. nat. • 11 • 2001 • Suplement - Abstracts
Interdisciplinary Workshop "Pattern and Process in Balkan Biodiversity", Koper, September 25-28 2001
A ZOOGEOGRAPHICAL REVIEW OF THE SPIDERS (ARANEAE) OF THE BALKAN PENINSULA
Christo DELTSHEV 
Institute of Zoology of the Bulgarian Academ y of Sciences, Sofia, Bulgaria
According to their current distribution, the over 1,400 established spider species can be classified into 24 zoo- 
geographical categories, grouped into 4 complexes (widely distributed, European, Balkan endemic and Mediterra­
nean). The largest number of species belongs to the widely distributed complex, but the most characteristic are the 
Balkan endemics. The established number (389) in the latter category is high and reflects the local character of the 
fauna. In the context of palaeoenviromental changes since Pliocene, this phenomenon can be attributed to the rela­
tive isolation of the mountains compared to the lowlands. Moreover, the high percentage representation of endemics 
suggests an important process of autochthonous speciation. Thus, the Balkan Peninsula can be considered as being a 
major centre of speciation for the European araneofauna.
Key words: spiders, diversity, endemicity, Bulgaria, speciation
MAMMAL BIODIVERSITY IN THE BALKANS
Boris KRYSTUFEK 
Slovenian Museum of Natural History, Ljubljana, Slovenia
Mediterranean Europe is known to be a host of endemic taxa in general and in rodents in particular. In compari- 
sion with the remaining peninsulas (the Iberian and the Italian), the Balkans are particularly rich in both phyloge­
netic and biogeographic relics. It has been shown that the hot spots of European rodent diversity are focused in the 
Balkan Peninsula (including the Carpathian Basin) and adjacent parts of southern Ukraine and Ciscaucasia, where 
>80% of rodent genera and species occur on merely 11.4% of the continent's surface (Krystufek & Griffiths, in 
press). Among the eight mainland European rodents with particularly restricted distributional ranges (range encom­
passing <1% of the continent's surface), no less than five are from the Balkans (Mesocricetus newtoni, Dinaromys 
bogdanovi, Microtus felteni, M. tatricus, Miomymus roachi), and a number of other species have similarly narrow 
ranges (e.g. Spermophilus citellus, Nannospalax arenarius, Microtus thomasi, Apodemus mystacinus s. s.). Due to 
high chromosomal polymorphism in some taxa on one hand (particularly Nannospalax leucodon, but also Sorex 
araneus and Microtus thomasi) and a lack of comprehensive taxonomic treatments on the other, the number of taxa 
with very restricted ranges is likely to be higher than actually recognised. In addition, the island of Crete hosts two 
island endemics (Crocidura zimmermani, Acomys nesiotes) out of the three documented for Europe. This accords 
with the-oft suggested role of the Balkans as a Quaternary refugium - based on its age as a distinct landscape unit 
and also because of complex Plio-Pleistocene vicariant interactions between the Balkans and Anatolia. In general, 
mammalian spatial patterns have been poorly documented and studied - e.g. Mediterranean small mammal com­
munities are less species rich than are continental ones, and the transition between the two lies at c. 700-900 m on 
the Dinaric Alps (north-western Balkans; Krystufek & Griffiths, 1999). Mustelids show a monotonous latitudinal de­
cline in a-diversity, with their highest values in the Carpathian Basin (Krystufek, 2000).
Key words: mammals, refugia, biodiversity, authochthony
References:
Krystufek, B. (2000): Mustelids in the Balkans - small carnivores in the European biodiversity hot-spot. In: Griffiths, 
H. I. (ed.): Mustelids in a modern world. Management and conservation aspects of small carnivore: human interac­
tions, Backhuys Publishers, Leiden, pp. 281-294.
Krystufek, B. & H. I. Griffiths (1999): Mediterranean v. continental small mammal communities and the environ­
mental degradation of the Dinaric Alps. J. Biogeography, 26, 167-177.
Krystufek, B. & H. I. Griffiths (in press): Species richness and rarity in European rodents. Ecography.
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