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The faunistic diversity of cave-dwelling spiders (Arachnida, Araneae) of Greece

The faunistic diversity of cave-dwelling spiders (Arachnida, Araneae) of Greece

Abstract

Until today, from Greek caves a total of 109 species of spiders belonging to 25 families are known. One species, the linyphiid Porrhomma convexum (Westring, 1861) was recorded here for the first time in Greece. The 109 species are distributed in caves of different geographic territories as follows: Thrace – 8 species, Macedonia – 18, Epirus – 1, Thessaly – 6, Central Greece – 3, Attiki-Saronic Islands – 24, Peloponnese – 15, Evoia-Vories Sporades – 1, Eastern Aegean Islands – 5, Cyclades – 3, Dodecanese – 6, Ionian Islands – 23, Crete – 47. The largest fraction of troglobite species were encountered mainly in the territories of Crete – 15 species (5 of which are anophthalmic), the Ionian Islands – 4, Thrace – 2 (both anophthalmic), the Attiki-Saronic Islands – 2 (both anophthalmic), the Peloponnese – 2 (one anophthalmic), and Macedonia, Thessaly, and the Cyclades – each with 2 species. The richness of the troglobitic spiders in these regions strengthens the assumption that they were major centres of speciation and evolution for the species of this group. According to their current distribution, the established 109 species can be classified into 12 zoogeograpical categories, grouped into 4 complexes (widely distributed, European, Mediterranean, endemics). The largest number of species belong to the endemic complex (53.2 %) and are also the most characteristic and reflect the local character of the cave-dwelling spiders.

A survey of spiders (Araneae) inhabiting the euedaphic soil stratum and the superficial underground compartment in Bulgaria

A survey of spiders (Araneae) inhabiting the euedaphic soil stratum and the superficial underground compartment in Bulgaria

Abstract

In 2005 a team of Bulgarian zoologists started a project aiming to study the invertebrates inhabiting the deeper soil stratum (euedaphon) and the Superficial Underground Compartment (SUC) in Bulgaria. In the course of a four-year sampling, a total of 52 species of spiders were caught from 19 collecting sites and 9 geographical regions. They belong to the following families: Scytodidae (1), Segestriidae (1), Dysderidae (8), Nesticidae (1), Anapidae (1), Theridiidae (1), Linyphiidae (20), Agelenidae (3), Cybaeidae (1), Dictynidae (2), Amaurobiidae (2), Liocranidae (3), Corinnidae (1), Zodariidae (1), Gnaphosidae (5), and Salticidae (1). The family Anapidae, with the species Zangherella relicta (Kratochvíl, 1935) is recorded from three sites in the Pirin and Slavyanka mountains, and this represents the first record of the family, genus and species in Bulgaria. In spite of the active investigations of the epigean and cave spiders in these regions over the years Z. relicta was not found and it seems it occurs only in deeper subterranean habitats and nowhere else. Comparative study of almost topotypic specimens of Z. relicta from Montenegro with those collected from Bulgaria showed no variation in the shape of palp and female vulvae. Until the true identity of Z. apuliae (Caporiacco, 1949) from Italy is revealed, it remains unclear whether Z. relicta and Z. apuliae are conspecific, as it remains unclear whether the older records of Z. apuliae from the Balkan Peninsula refer to this species or to Z. relicta. Pelecopsis mengei (Simon, 1884) (Linyphiidae) and Scotolathys simplex Simon, 1884 (Dictynidae) are also reported from Bulgaria for the first time, the latter being also new to FYR of Macedonia. A faunistic overview of the spiders found in these underground environments is made, along with remarks on the distribution and ecology of some rare and interesting species. The presence of cave-dwelling and superficial spiders in the sampled sites indicates that SUC and euedaphon are inhabited by different ecotypes, e.g. litter- (tanathostromic), soil- (edaphic) and cave-(troglobitic) which at some places co-occur.

The first fossil cyphophthalmid harvestman from Baltic amber

The first fossil cyphophthalmid harvestman from Baltic amber

Abstract

The first fossil cyphophthalmid harvestman (Opiliones: Cyphophthalmi) from Palaeogene (Eocene) Baltic amber is described. This is only the third fossil example of this basal harvestman lineage; the others being from the probably slightly younger Bitterfeld amber and the much older, early Cretaceous, Myanmar (Burmese) amber. Although incomplete and lacking most of the appendages, the new Baltic amber fossil can be identified as a female. The somatic characters preserved, especially spiracle morphology and the coxo-genital region, allow it to be assigned with some confidence to the extant genus Siro Latreille, 1796 (Sironidae). This fossil is formally described here as Siro balticus sp. nov. It resembles modern North American Siro species more than modern European ones, and can be distinguished principally on its relatively large size and the outline form of the body.

Spiders in a hostile world (Arachnoidea, Araneae)

Spiders in a hostile world (Arachnoidea, Araneae)

Abstract

Spiders are powerful predators, but the threats confronting them are numerous. A survey is presented of the many different arthropods which waylay spiders in various ways. Some food-specialists among spiders feed exclusively on spiders. Kleptoparasites are found among spiders as well as among Mecoptera, Diptera, Lepidoptera, and Heteroptera. Predators are found within spiders’ own population (cannibalism), among other spider species (araneophagy), and among different species of Heteroptera, Odonata, and Hymenoptera. Parasitoids are found in the orders Hymenoptera and Diptera. The largest insect order, Coleoptera, comprises a few species among the Carabidae which feed on spiders, but beetles are not represented among the kleptoparasites or parasitoids.

Endemic harvestmen and spiders of Austria (Arachnida: Opiliones, Araneae)

Endemic harvestmen and spiders of Austria (Arachnida: Opiliones, Araneae)

Abstract

A comprehensive overview of plant, fungus and animal species of Austria revealed a total of 748 endemic and subendemic species, including, 11 harvestman and 46 spider species. Altogether two endemic harvestmen (Nemastoma bidentatum relictum, Nemastoma schuelleri) and 8 endemic spiders (Abacoproeces molestus, Collinsia (caliginosa) nemenziana, Mughiphantes severus, Mughiphantes styriacus, Pelecopsis alpica, Scotophaeus nanus, Troglohyphantes novicordis, Troglohyphantes tauriscus), beside 9 subendemic harvestman and 38 subendemic spider species have been recorded from Austria. Hot-spots of endemism in the Eastern Alps are the north-eastern (Ennstaler Alps) and southern Calcareous Alps (Karawanken, Karnische Alps) and the Central Alps (Hohe Tauern, Gurktaler Alps, Ötztaler and Stubaier Alps). Most of the endemic arachnid species occur from the nival down to the montane zone. Important habitats are rocky areas, caves and woodlands. High absolute numbers and percentages of endemics can be found within the harvestman families Cladonychiidae, Ischyropsalididae and Nemastomatidae and in the spider genera Lepthyphantes s. l. and Troglohyphantes. The conservation status of these highly endangered taxa – 85 % of the spider species and 100 % of the harvestman taxa are endangered in Austria – is poor.

Ground-living spiders (Araneae) at polluted sites in the Subarctic

Ground-living spiders (Araneae) at polluted sites in the Subarctic

Abstract

Spiders were studied around the Pechenganikel smelter combine, Kola Peninsula, north-western Russia. The average spider density was 6-fold greater and the density of Linyphiidae specimens 11.5-fold higher at slightly polluted sites, compared with heavily polluted sites. Altogether, 18 species from 10 families were found at heavily polluted sites, the theridiid Robertus scoticus clearly dominating (23.3 % of identifiable specimens), also Neon reticulatus (9.6 %), Thanatus formicinus (9.6 %) and Xysticus audax (8.2 %) were abundant. The most numerous among 58 species found at slightly polluted sites were Tapinocyba pallens (18.5 %), Robertus scoticus (13.7 %), Maso sundevalli (9.5 %) and Alopecosa aculeata (8.2 %). The family Linyphiidae dominated at slightly polluted sites, 64 % of species and 60 % of individuals; compared with heavily polluted sites, 23 % and 38 % respectively.

Arachnologische Mitteilungen 40, 2011 = European Arachnology 2009. Proceedings of the 25th European Congress of Arachnology, Alexandroupoli, 16–21 August 2009

Arachnologische Mitteilungen 40, 2011 = European Arachnology 2009. Proceedings of the 25th European Congress of Arachnology, Alexandroupoli, 16–21 August 2009

Ground spider communities in experimentally disturbed Mediterranean woodland habitats

Ground spider communities in experimentally disturbed Mediterranean woodland habitats

Abstract

The protected Mediterranean woodland habitats in Israel are undergoing tree encroachment, resulting in loss of open patches with herbaceous vegetation. We suggested that this process results in a ground spider community dominated by shade-loving species. At three Mediterranean woodland sites located along a rainfall gradient, we examined the effects on the ground-spider community of experimental removal of the woody vegetation in 1000 m2 plots by cutting and overall plant biomass reduction by grazing and browsing by livestock. Pitfall traps were placed in replicated plots of four treatments (control, cutting, grazing/browsing, and cutting together with grazing/browsing) and in two different habitat patch types (open, woody). ANOVA and multivariate analyses were performed on family abundance by treatment and habitat patch type. Tree-cutting reduced the number of families in plots at two of the three sites. Grazing did not have a significant effect on the number of families or on the ground spider community composition. The spider community of cut-woody patches was more similar to that of open patches than to that of uncut woody patches. Most spider families separated along an axis of open versus woody patches, with woody habitat families predominating at all sites. Families typical of open habitats were positively associated with cut-woody patches as well. The overall effect on ground spider diversity of such manipulations may depend on the scale of habitat changes.

Spatial and temporal structure of the spider community in the clay semi-desert of western Kazakhstan

Spatial and temporal structure of the spider community in the clay semi-desert of western Kazakhstan

Abstract

The spatial and temporal structure of spider communities was studied in the clay semi-desert of the north-western Caspian Lowland, western Kazakhstan (49°23' N, 46°47' E). The soils and vegetation are complex, being composed of a mosaic of desert and steppe plant communities. Besides the native associations, there are plantations of different tree species. The ground-dwelling spider assemblages in the native habitats are the most diverse. The number of species inhabiting forest plantations is three times as small. Gnaphosidae is the leading family in the ground layer. They show high abundance and diversity levels during the whole season. Thomisidae, Lycosidae, Philodromidae, and Salticidae are abundant as well. The species diversity of herbage-dwelling spiders in different open native habitats is very similar. The spectrum of dominant families (Thomisidae, Oxyopidae, Araneidae, and Salticidae) and the seasonal dynamics of their ratio in desert and steppe associations have much in common. Spider assemblages of native and artificial habitats are characterised by change from multispecies polydominant spring-summer communities to impoverished imbalanced autumn ones. Seasonal changes in the species structure of mature spider groupings in native habitats are well pronounced, while the impact of seasonal conditions is even stronger than between-habitat differences. Complexes of typical species with different levels of habitat preference are revealed.

Regional variations in agrobiont composition and agrobiont life history of spiders (Araneae) within Hungary

Regional variations in agrobiont composition and agrobiont life history of spiders (Araneae) within Hungary

Abstract

Agrobiont spider species are well adapted to arable systems, which have fairly uniform vegetation structure and pest assemblages over continent-wide areas. We wanted to study, whether agrobiont spider subassemblages and the life history of the most prominent agrobiont, Pardosa agrestis, show any regional variation within Hungary, where only modest climatic differences exist between the NW and SE parts of the country. We studied agrobiont species of spider assemblages in 27 alfalfa and 21 cereal fields with suction sampling and pitfalls. The similarity structure of these agrobiont sub-assemblages (Sørensen distance measure) was congruent with the geographic distance matrices (Eucledian distance), as tested by Mantel tests. However, if we considered sub-assemblages consisting of the non-agrobiont species, this congruency was always higher. Thus, agrobionts responded only moderately to geographical variation if we compare them to non-agrobiont species. We studied the generation numbers and the occurrence of the first adult individuals in P. agrestis; the most common agrobiont spider in Hungary. This comparison involved comparing fields along a NW – SE gradient during 6 sampling years in pairwise comparisons, where in each year a northern and a southern population was compared with a minimum distance of 126 km in between. In generation numbers there was no difference; we found two generations across Hungary. In contrast, the first occurrence of adult individuals was on average 15 days earlier in both generations in the more southern populations. Thus, it can be concluded that agrobionts show a fairly stable and relatively low magnitude response over country-sized geographical ranges.

Cryptachaea blattea, eine weitere nach Deutschland eingeschleppte Spinnenart (Araneae: Theridiidae)

Cryptachaea blattea, a further spider species introduced into Germany (Araneae: Theridiidae)

Abstract

Cryptachaea blattea (Urquhart, 1886) has been recorded for the first time from Germany (Nordstemmen, rural district of Hildesheim, Lower Saxony). One male was found by means of pitfall traps in a tree and shrub nursery. The species was most likely introduced with plants or cargo. Information about its appearance, habitat, and distribution are given.

Spinnen (Arachnida, Araneae) im Winter - kleinräumige Unterschiede als Folge tageszeitlicher Temperaturschwankungen

Spiders (Arachnida, Araneae) in winter - differences in the appearance of species in small-scale spaces as a response to daily temperature fluctuations

Abstract

Pitfall traps were positioned for the investigation of the spider fauna at the northern and southern slopes of three mountain ridges (Chilchberg, Riedberg, and Buechenberg, municipalities Nunningen and Zullwil, canton Solothurn, Switzerland) within the Swiss Jura Mountains. The temperature in the upper litter was measured at three hour intervals. Independent of the weather more or less clear differences between northern and southern slopes could be observed. Maximum day temperature fluctuations of 15.8 °C were measured.

There were no significant differences in spider communities based on quantitative comparison methods. However, a qualitative analysis showed major differences in species composition. More than 50% of all species per investigation area showed clear preferences for the northern or the southern slope, with more then two thirds of the individuals only found on either the north or south slopes.

Description of the male of Steatoda ephippiata (Araneae: Theridiidae)

Description of the male of Steatoda ephippiata (Araneae: Theridiidae)

Abstract

The previously unknown male of Steatoda ephippiata (Thorell, 1875) is described from recently collected material in Tunisia. Some new distribution records for the species are added and all known records are mapped.

Nesticodes rufipes – Erstnachweis einer pantropischen Kugelspinne in Deutschland (Araneae: Theridiidae)

Nesticodes rufipes – first record of a pantropical spider in Germany (Araneae: Theridiidae)

Abstract

Records of Nesticodes rufipes (Lucas, 1846) from Saxony, Germany are presented. The three females of Nesticodes rufipes were found associated with the zoo trade in the cities of Chemnitz and Plauen in cricket boxes. Female genitalia are illustrated.

The canopy spiders (Araneae) of the floodplain forest in Leipzig

The canopy spiders (Araneae) of the floodplain forest in Leipzig

Abstract

The canopy spiders of the floodplain forest in Leipzig have become a focus of ecological studies in recent years. In 2006 we sampled 30 tree canopies in the ‘Burgaue’ nature reserve with pyrethrum knock-down fogging, recording 502 adult spiders belonging to 48 species and 11 families. Based on these data and the results of a previous fogging study, the studied spider community was dominated by forest and forest-edge species with a preference for the shrub and canopy strata as well as by spiders of the web spider feeding guild. The community structure was typical for arboreal spider communities from northern temperate forests but very different from communities in the tropics. Species richness and evenness were similar to the old growth near-primary Białowieża Forest in Poland. The checklist of 96 canopy spider species of the floodplain forest of Leipzig includes 54 additions to the spider fauna of Leipzig and vicinity by recent canopy studies and eight first canopy records for Leipzig from our field work. The theridiid Dipoena torva (Thorell, 1875) was recorded for the first time in Saxony. The floodplain forest of Leipzig sustains a large and species-rich arboreal spider community and is thus a valuable habitat for a large proportion of endangered species (12%).

Christian Kropf & Peter Horak (Hrsg.) (2009): Towards a natural history of arthropods and other organisms. In memoriam Konrad Thaler

Christian Kropf & Peter Horak (Hrsg.) (2009): Towards a natural history of arthropods and other organisms. In memoriam Konrad Thaler

Abstract

book review: Christian Kropf & Peter Horak (Hrsg.) (2009): Towards a natural history of arthropods and other organisms. In memoriam Konrad Thaler

P.A. Sebastian & K.V. Peter (Hrsg.) (2009): Spiders of India

P.A. Sebastian & K.V. Peter (Hrsg.) (2009): Spiders of India

Abstract

book review: P.A. Sebastian & K.V. Peter (Hrsg.) (2009): Spiders of India

Einmal Siedlce und wieder zurück – der 18. Internationale Kongress der Arachnologen in Polen

Einmal Siedlce und wieder zurück – der 18. Internationale Kongress der Arachnologen in Polen

Abstract

congress report

Bericht zur AraGes-Tagung 2010 und zur 5. Mitgliederversammlung der Arachnologischen Gesellschaft von 17. bis 19. September 2010 in Berlin

Bericht zur AraGes-Tagung 2010 und zur 5. Mitgliederversammlung der Arachnologischen Gesellschaft von 17. bis 19. September 2010 in Berlin

Abstract

congress report

Cover/Contents Arachnologische Mitteilungen 39, 2010

Cover/Contents Arachnologische Mitteilungen 39, 2010