Spider records from East Macedonia and Thrace ( NE Greece )

The present study summarises spider records from East Macedonia and Thrace (NE Greece). Spiders were mainly collected by hand sampling and to a smaller extent by pitfall trapping during field trips in 2002, 2004, 2007, 2008 and 2009. 171 species from 23 families were sampled. Pelecopsis pavida (O. P.-Cambridge, 1872) (Linyphiidae) and Xysticus kaznakovi Utochkin, 1968 (Thomisidae) were new to the European spider fauna and ten further species, Diaea livens Simon, 1876, Heriaeus graminicola (Doleschall, 1852), Meioneta ressli Wunderlich, 1973, Oedothorax retusus (Westring, 1851), Philodromus albidus Kulczynski, 1911, Pocadicnemis pumila Keyserling, 1880, Sitticus saltator (O. P.-Cambridge, 1868), Stemonyphantes lineatus (Linnaeus, 1758), Synageles scutiger Prószynski, 1979 and Thanatus coloradensis Keyserling, 1880, could be added to the Greek fauna for the first time. 21 and 38 species were new to East Macedonia and Thrace, respectively. Based on previous work, plus the present study, the Greek spider fauna now includes 1,108 species.

The Balkan Peninsula is a biodiversity hotspot (Hubenov 2004, Krystufek & Reed 2004, Popov & Fet 2007) which comprises a very species rich spider fauna (Deltshev 1999(Deltshev , 2005)).Northern Greece -part of the Balkan Peninsula -is situated in the transition zone of the European, Mediterranean and the Ponto-Anatolian biogeographical regions, which results in a high biodiversity ( Jerrentrup et al. 1989, Schröder et al. 2011).Despite an increasing number of faunistic surveys (Buchholz 2007, Van Keer et al. 2010, Schröder et al. 2011) as well as taxonomic works (for an extensive compilation see Bosmans &Chatzaki 2005 andVan Keer et al. 2010) the spider fauna of Northern Greece, and especially Thrace, is still poorly investigated and thus remains underestimated (Chatzaki 2008).The present study summarises spider data which were recorded in the Eastern part of Northern Greece, namely East Macedonia and Thrace, and thus is intended to enhance current knowledge concerning spider distribution in this region.

Study area
Data were collected in the region of East Macedonia (prefectures Drama, Kavála, Thassos) and Thrace (prefectures Evros, Rhodopi, Xanthi) (Tab. 1, Fig. 1) which are situated in the north-eastern part of Greece and separated by the Nestos river.The study area is delimited by the Bulgarian border to the north and the Turkish border or Evros river to the east, while the coastline of the Thracian Sea forms the southern border.
The northern part of north-east Greece is characterised by mountain ranges such as the Greek Rhodope massif along the Greek-Bulgarian border reaching altitudes of about 1950 m above sea level as well as the Pangaion, Menoikon, Lekani and Falakron mountains; the latter reaches the highest altitudes (2232 m a.s.l.).Towards the east, a lower mountainous area with altitudes not exceeding 650 m a.s.l.exists in the area of the Dadia nature reserve.In a southern and south-eastern direction the landscape becomes gradually lower and, via a belt of cultivated land, changes into the coastal plain of the Aegean Sea.Near the coast the landscape is formed by level to slightly undulated lowlands about 20 m above sea level.In the study area two rivers (Nestos, Evros) form deltas which are largely cultivated, but also still contain many natural habitats such as lagoons, salt marshes and remnants of floodplain forests.The Nestos delta includes the lagoon areas of Keramotí and Agiasma, and the eastward situated Lakes Vistonis and Mitrikou form the east Macedonian-Thracian wetland belt, which comprises a considerable number of natural lagoons and salt marshes.
The climate of the coastal plains is Mediterranean, although continental impacts become effective.Impacts manifest themselves as huge fluctuations in yearly temperature, with summer maxima of 40 °C Sascha BUChhOLz, TU Berlin, Institut für Ökologie, Rothenburgstraße 12, 12165 Berlin, Germany, e-Mail: sascha.buchholz@tu-berlin.de submitted 28.2.2013, accepted 13.4.2013, online 13.5.2013Tab.1: Geographical information on the sampling localities.and winter minima of -20 °C.The annual average amount of precipitation is 600-700 mm ( Jerrentrup et al. 1989), whereas the average annual temperature is 11 °C (Lienau 1989).The climate of the mountain ranges shows typical Central European characteristics with snow from November to May (Volpers 1988).The potential natural vegetation along the coast is the Ostryo-Carpinion followed by Quercion frainetto-zone up to altitudes of 1000 meters above sea level (Horvat et al. 1974).At about 1000 meters the oak-zone changes into a beech-zone with spruce (Picea abies) and fir (Abies) (Volpers 1988, Lienau 1989).

Methods
Spiders were mainly collected by hand sampling and to a lesser extent by pitfall traps during field trips in 2002, 2004, 2007, 2008 and 2009.A broad variety of habitat types were sampled in 21 locations in East Macedonia and Thrace (Tab. 1, Fig. 1).Nomenclature and information on zoogeographical distribution of species were taken from Helsdingen (2012) and Platnick (2013) and more detailed literature on local elements.Bosmans & Chatzaki (2005), Buchholz (2007), Chatzaki (2008), Bosmans (2009), Bosmans et al. (2009), Van Keer et al. (2010) and Schröder et al. (2011) were consulted to identify those new records (indicated by 'nr' in Tab. 2) that the present study added to the list of known species in Greece, Macedonia and Thrace.By contrast, the '+' sign in Tab. 2 indicates species that were already recorded in the area.
Xysticus kaznokovi has been recorded in Central Asia (Marusik & Logunov 1990) and Turkey, where it was collected under stones and on the ground in grass (Demir et al. 2009).One male was caught in a dry and sparse vegetated habitat.Twenty-one and thirty-eight species were new to East Macedonia and Thrace, respectively.In addition to Pelecopsis pavida and Xysticus kaznakovi, ten further species could be added to the Greek fauna for the first time: Oedothorax retusus, Pocadicnemis pumila and Stemonyphantes lineatus are widespread across Europe (Nentwig et al. 2013) and inhabit a broad variety of habitats (Hänggi et al. 1995).
Sitticus saltator is also an element of the European fauna (Nentwig et al. 2013), but its occurrence seems to be restricted to dry habitats such as dry grassland, heathland and dunes (Bauchhenß 1995, Merkens 2002, Buchholz & Kreuels 2009, Buchholz & Schirmel 2011) and accordingly three females were found in a white dune of the Nestos delta.
Meioneta ressli (det.R. Bosmans) and Thanatus coloradensis (det.C. Muster) are high mountain species (Muster 2001, Nentwig et al. 2013).While the latter was found in meadows of the European mountains (Alps, Pyrenees, Carpathians, Caucasus) (Nentwig et al. 2013), Meioneta ressli was hitherto considered an endemic species of the Alps (Muster 2001) inhabiting alpine grass heaths and as far down as the valley (Thaler 1995, Muster 2001, Höfer et al. 2010).In the present study, Thanatus coloradensis was sampled in dry grasslands of the Falakron mountain while Meioneta ressli was found at the same habitat type in the Nestos canyon.
Diaea livens has been found in Western, Central and Southern Europe (Lazarov 2007, Bayram et al. 2013, Nentwig et al. 2013) as well as in the Caucasus (Otto & Tramp 2011, Nentwig et al. 2013) but was also introduced into the USA (Platnick 2013).Diaea livens is arboreal (mainly oaks) (Nentwig et al. 2013) and accordingly this species was caught in dwarf-shrubs.
Heriaeus graminicola is distributed in Central, Eastern and South-Eastern Europe (Deltshev et al. 2004, Nentwig et al. 2013) and according to Hänggi et al. (1995) and Nentwig et al. (2013) it inhabits dense vegetated and humid habitats (e.g., reedy marsh).By contrast, a number of individuals were sampled in different and mostly dry habitats.
Synageles scutiger (det.D. Logunov) has been rarely recorded.According to Logunov & Marusik (2000) and Platnick (2013) it was only found in  Ukraine and Azerbaijan.One female was caught in a white dune of the Nestos delta.Knowledge of the distribution patterns and ecology of several of the species caught is still poor, and more faunistic and especially ecological studies are needed to gain a better understanding of the Greek but also of the Eastern Mediterranean spider fauna.However, based on previous work (Bosmans & Chatzaki 2005, Bosmans et al. 2009, Van Keer et al. 2010, Schröder et al. 2011), together with the present study, the Greek spider fauna now includes 1,108 species.

Fig. 1 :
Fig. 1: Map of study area and location of sampling sites in East Macedonia (west of the Nestos river) and Thrace (east of the Nestos river) (pale area = lowland, grey area = mountain range).For further geographical information see Tab. 1.