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Nemastoma bidentatum Roewer, 1914 is a complex of closely related litter-dwelling harvestmen, characterized by a penis glans with two pairs of lateral lancet-like spines, and a femur IV with a saw-like series of pointed tubercles. Here we a) revise the hitherto known taxa within the N. bidentatum complex, and b) analyze in detail the relations among the taxa in Slovenia. The study revealed that the N. bidentatum complex consists of four species: N. bidentatum Roewer, 1914 s. str., N. relictum Gruber & Martens, 1968 stat. nov., N. pluridentatum (Hadži, 1973) stat. nov. and N. kozari Novak, Kozel, Podlesnik & Raspotnig sp. nov. Moreover, N. bidentatum s. str. consists of six subspecies: N. bidentatum bidentatum Roewer, 1914, N. bidentatum sparsum Gruber & Martens, 1968, N. bidentatum gruberi Novak, Slana Novak, Kozel & Raspotnig ssp. nov., N. bidentatum martensi Novak, Slana Novak & Raspotnig ssp. nov., N. bidentatum schmidti Novak, Raspotnig & Slana Novak ssp. nov. and N. bidentatum sneznikensis Novak, Komposch, Slana Novak & Raspotnig ssp. nov. In Slovenia, the six subspecies of N. bidentatum form a parapatric complex around N. bidentatum schmidti. Hybrids occur in the contact zones between adjacent subspecies, but they are missing between distant subspecies. The taxonomic distinction of lineages / subspecies is congruent with their distribution patterns. With six of the nine taxa present, Slovenia is considered the center of the N. bidentatum complex speciation. At the time being, this complex is the most diversified harvestman group on a subspecific and young-species level and provides important details on speciation processes in Opiliones.

When threatened, the harvestman Egaenus convexus (Opiliones: Phalangiidae) ejects a secretion against offenders. The secretion originates from large prosomal scent glands and is mainly composed of two isomers of 4-hydroxy-5-octyl-4,5-dihydro-3H-furan-2-one (1), a β-hydroxy-γ-lactone. The compounds were characterized by GC-MS of their microreaction derivatives, HRMS, and NMR. After the synthesis of all four possible stereoisomers of 1, followed by their separation by chiral-phase GC, the absolute configurations of the lactones in the Egaenus secretion was found to be (4S,5R)-1 (90%) and (4S,5S)-1 (10%). Hydroxy-γ-lactones represent a new class of exocrine defense compounds in harvestmen.

When threatened, the harvestman Egaenus convexus (Opiliones: Phalangiidae) ejects a secretion against offenders. The secretion originates from large prosomal scent glands and is mainly composed of two isomers of 4-hydroxy-5-octyl-4,5-dihydro-3H-furan-2-one (1), a β-hydroxy-γ-lactone. The compounds were characterized by GC-MS of their microreaction derivatives, HRMS, and NMR. After the synthesis of all four possible stereoisomers of 1, followed by their separation by chiral-phase GC, the absolute configurations of the lactones in the Egaenus secretion was found to be (4S,5R)-1 (90%) and (4S,5S)-1 (10%). Hydroxy-γ-lactones represent a new class of exocrine defense compounds in harvestmen.

The homologous and phylogenetically old scent glands of harvestmen-also called defensive or repugnatorial glands-represent an ideal system for a model reconstruction of the evolutionary history of exocrine secretion chemistry ("phylogenetic chemosystematics"). While the secretions of Laniatores (mainly phenols, benzoquinones), Cyphophthalmi (naphthoquinones, chloro-naphthoquinones, methyl-ketones) and some Eupnoi (naphthoquinones, ethyl-ketones) are fairly well studied, one open question refers to the still largely enigmatic scent gland chemistry of representatives of the suborder Dyspnoi and the relation of dyspnoan chemistry to the remaining suborders. We here report on the secretion of a nemastomatid Dyspnoi, Nemastoma triste, which is composed of straight-chain methyl-ketones (heptan-2-one, nonan-2-one, 6-tridecen-2-one, 8-tridecen-2-one), methyl-branched methyl-ketones (5-methyl-heptan-2-one, 6-methyl-nonan-2-one), naphthoquinones (1,4-naphthoquinone, 6-methyl-1,4-naphthoquinone) and chloro-naphthoquinones (4-chloro-1,2-naphthoquinone, 4-chloro-6-methyl-1,2-naphthoquinone). Chemically, the secretions of N. triste are remarkably reminiscent of those found in Cyphophthalmi. While naphthoquinones are widely distributed across the scent gland secretions of harvestmen (all suborders except Laniatores), methyl-ketones and chloro-naphthoquinones arise as linking elements between cyphophthalmid and dyspnoan scent gland chemistry.

Fragestellung: Spinnen rufen bei Menschen der westlichen Bevölkerung häufig Gefühle von Angst und Ekel hervor und gelten daher als die unbeliebtesten aller Arthropoden. Die klinisch relevante Ausprägung dieser Angst, die Spinnenphobie, ist eine häufig auftretende Angststörung, die meist in der frühen Kindheit beginnt und ohne Behandlung bis ins Erwachsenenalter chronisch verläuft. Ätiologische Modelle betonen die Rolle des Modelllernens und der negativen Informationstransmission bei der Entstehung der Störung. Obwohl sehr wirkungsvolle psychotherapeutische Methoden zur Verfügung stehen, werden diese Kindern oft vorenthalten. Meist wird eine spontane Remission erwartet, die jedoch sehr selten ist. Methodik: In der vorliegenden Studie wurde ein psychoedukatives Programm zum Thema Spinnen für Grundschulkinder entwickelt und dessen Wirksamkeit an einer Gruppe von 36 Kindern im Alter von 8 bis 10 Jahren evaluiert. Das Ziel der Pilotstudie war es, vor allem die Durchführbarkeit des Programmes zu überprüfen. Ergebnisse: Es zeigte sich eine Reduktion der Spinnenängstlichkeit durch Psychoedukation bei Mädchen und Jungen mit hoher oder moderater Spinnenängstlichkeit. Schlussfolgerungen: Das Programm könnte einen wertvollen Beitrag in der Prävention von Spinnenphobie leisten und sollte im Rahmen zukünftiger kontrollierter Studien überprüft werden.

The exocrine secretions from prominently developed prosomal scent glands in four species of the European laniatorean harvestman genus Holoscotolemon (Laniatores, Travunioidea, Cladonychiidae) were analyzed by gas chromatography – mass spectrometry. Two major alkaloidal compounds were detected: Nicotine accounted for more than 97% of the secretion in Holoscotolemon jaqueti and H. oreophilum, whereas the chemically related nicotinoid alkaloid anabaseine was the major compound in H. lessiniense. In addition, a series of minor nitrogen-containing components was found, namely 3-(1-methyl-2-piperidinyl)-pyridine and anabasine, in H. jaqueti and H. oreophilum, and anabasine together with 2,3′-bipyridyl in H. lessiniense. By contrast, extracts of adult H. unicolor did not show any components. In one juvenile specimen of H. unicolor, however, low amounts of alkyl pyrazines (dimethyl-isobutyl- and dimethyl-isopentylpyrazines) were detected. Nitrogen-containing components previously were found in Sclerobunus robustus (an American travunioid harvestman), so scent gland-derived alkaloids may be widespread or even common in the Travunioidea. Alkaloids have not been reported for other opilionid scent gland secretions outside the Travunioidea, and we hypothesize that they may be the phylogenetically ancestral allomones in the Laniatores, having been reduced and replaced by a phenol- and benzoquinone-rich chemistry in the more derived grassatorean taxa.

The morphology of the scent glands of Trogulus tricarinatus (Linnaeus 1767) (Trogulidae), a small, soil-dwelling opilionid species, was investigated by means of serial histological semi thin-sections. The glands constitute paired prosomal glandular sacs that open to the body surface via one pore (ozopore) on either side of the body, dorsally adjacent to coxae I. Consistent with the generally recognized organization of scent glands in Opiliones, an anterior non-secretory region of the reservoir could be distinguished from a posterior secretory area, the latter characterized by a thick vacuolated epithelium. However, there are several unusual scent gland features in T. tricarinatus. First, the ozopores are hidden, with each being surrounded by a kind of external secretion atrium formed by a dorso-lateral integumental fold (dorsal limitation), coxa I (ventral limitation), and a wall of projecting cuticular papillae (outer lateral limitation). A horizontal slit (''secondary opening'') between the top of this wall and the dorsal integumental fold is externally visible. Secondly, no fluid, but solid spherical structures that may represent condensed secretion are found in the reservoirs. Thus, the secretion must pass through the external atrium before reaching the outside, perhaps as a gas produced by slow sublimation of solid secretion boli. Scent gland organization in T. tricarinatus, especially the findings of an external atrium around the ozopores, is not consistent with use in chemical defence, as is generally assumed for scent glands of Opiliones, but indicates a possibly non- defensive role.

Paired, sac-like and typically large opisthonotal glands (syn. oil glands), mainly considered for chemical protection and communication, characterize the so-called ‘glandulate Oribatida’ which include the Parhyposomata, Mixonomata, Desmonomata and Brachypylina but also the Astigmata. Among these groups distinct evolutionary trends affect the morphology of glands and their secretion profiles, thereby rendering them highly informative characters with phylogenetic significance. One striking tendency, convergently occurring in a few glandulate groups, leads to the degeneration or even complete regression of opisthonotal glands. In this study, a first example of coherent evolutionary steps towards opisthonotal gland degeneration is described by using desmonomatan Camisiidae as a model: Opisthonotal glands in representatives of genus Platynothrus still show morphologically and chemically ancient conditions with fairly-well developed glandular reservoirs. Secretion patterns mainly consist of a characteristic set of terpenes and aromatics (‘astigmatid compounds’) as found in outgroups such as desmonomatan Trhypochthoniidae. Progressive states of regression of opisthonotal glands, along with a reduction of component-richness and amounts of secretions, occur in representatives of Heminothrus and, more conspicuously, in species of Camisia, most likely indicating a consistent evolutionary trend. This trend towards opisthonotal gland atrophy may be due to novel alternative and cheap strategies of passive defense in more-derivative camisiids – such as mechanical protection by encrustation of the cuticle – that possibly compensate for the lack of chemical defenses.

In Western societies spiders are among the least liked of all arthropods, eliciting feelings of fear and disgust. The clinical manifestation of this fear - spider phobia - is a common anxiety disorder. In most cases the disorder has an early onset in childhood. The symptoms show a chronic course and can persist into adulthood if not treated. Etiological models emphasize the role of modeling and negative information transmission for the acquisition of the disorder. Even though powerful psychotherapeutic methods exist, referral to treatment is rather uncommon for children. Often spontaneous remission is expected, but that is atypical.The current study developed a psychoeducative program on spiders for elementary school children and evaluated it on a sample of 36 children aged 8 to 10 years. The main goal of this pilot study was to test the feasibility of the program.The study showed a reduction of fear of spiders after psychoeducation in girls and boys with previously high or moderate fear of spiders.The program could become a valuable contribution to the prevention of spider phobia and should be evaluated in future controlled trials.

The morphological organization and functional anatomy of prosomal defensive (scent) glands in Paranemastoma quadripunctatum, a representative of the dyspnoid harvestmen, was investigated by means of histological semithin sections, software-based 3D-reconstruction and scanning electron microscopy. Scent glands comprise large, hollow sacs on either side of the prosoma, each of these opening to the outside via one orifice (ozopore) immediately above coxa I. In contrast to the situation known from laniatorean, cyphophthalmid and some eupnoid Opiliones, ozopores are not exposed but hidden in a depression (atrium), formed by a dorsal integumental fold of the carapace and the dorsal parts of coxae I. Glandular sacs are connected to ozopores via a short duct which is equipped with a specific closing mechanism in its distal part: A layer of modified epidermal cells forms a kind of pad-like tissue, surrounding the duct like a valve. Several muscles attached to the anterior parts of the glandular reservoir and to the epithelial pad may be associated with ozopore-opening. The actual mechanism of secretion discharge seems to be highly unusual and may be hypothesized on the basis of corroborating data from behavioral observations, scent gland anatomy and secretion chemistry as follows: Enteric fluid is considered to be directed towards the ozopores via cuticular grooves in the surface of the coxapophyses of legs I. Then, the fluid is sucked into the anterior part of the scent gland reservoirs by the action of dorsal dilator muscles that widen the reservoir and produce a short-term negative pressure. After dilution/solution of the naphthoquinone-rich scent gland contents, a secretion-loaded fluid is thought to be discharged with the help of transversal compressor muscles. This is the first detailed study on the functional anatomy of scent glands and the mechanisms of secretion discharge in the Dyspnoi. J. Morphol. 2011. © 2011 Wiley-Liss, Inc.

Early in September, 130 arachnologists and 11 accompanying persons from 27 countries from all over the world headed to Israel to attend the 26th European Congress of Arachnology hosted by the Jacob Blaustein Institutes for Desert Research.

Extracts of Paranemastoma quadripunctatum (Opiliones, Dyspnoi, Nemastomatidae) contained seven components, all of which likely originated from the secretion of well-developed prosomal scent glands. The two main components (together accounting for more than 90% of the secretion) were identified as 1,4-naphthoquinone and 6-methyl-1,4-naphthoquinone. The minor components were 1,4-naphthalenediol, two methoxy-naphthoquinones (2-methoxy-1,4-naphthoquinone, and 2-methoxy-6-methyl-1,4-naphthoquinone) and two anthraquinones (2-methyl-9,10-anthraquinone and a dimethyl-9,10-anthraquinone). While some chemical data on scent gland secretions of the other suborders of Opiliones (Cyphophthalmi, palpatorean Eupnoi, and Laniatores) already exist, this is the first report on the scent gland chemistry in the Dyspnoi. Naphthoquinones are known scent gland exudates of Cyphophthalmi and certain Eupnoi, methoxy-naphthoquinones and anthraquinones are new for opilionid scent gland secretions.