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Birds increase crop yields via consumption of pests in some contexts but disrupt pest control via intraguild predation in others. Landscape complexity acts as an inconsistent mediator, sometimes increasing, decreasing, or not impacting pest control. Here, we examined how landscape context and seasonal variation mediate the impact of birds on arthropod pests and natural enemies, leaf damage, and yields of broccoli (Brassica oleracea) on highly diversified farms that spanned the USA west coast. Our study had two complementary components: a bird exclusion experiment and molecular diet analysis of 357 fecal samples collected from the most commonly captured bird species that also foraged in Brassica fields--American Goldfinch (Spinus tristis), American Robin (Turdus migratorius), Savannah Sparrow (Passerculus sandwichensis), Song Sparrow (Melospiza melodia), and White-crowned Sparrow (Zonotrichia leucophrys). Bird access yielded higher, rather than lower, numbers of pest aphids and increased their parasitism, while no other arthropods examined were consistently impacted. Independent of bird presence, percent natural cover in the landscape sometimes increased and sometimes decreased densities of arthropods in the mid-growth period, with diminishing impacts in the late-growth period. Herbivore feeding damage to broccoli leaves decreased with increasing amounts of natural land cover and in the late-growth period. Molecular diet analysis revealed that Brassica pests and predatory arthropods were relatively uncommon prey for birds. Landscape context did not alter the prey items found in bird diets. Altogether, our bird-exclusion experiment and molecular diet analysis suggested that birds have relatively modest impacts on the arthropods associated with broccoli plantings. More broadly, the limited support in our study for net natural pest control services suggests that financial incentives may be required to encourage the adoption of bird-friendly farming practices in certain cropping systems. [ABSTRACT FROM AUTHOR]

A case study of 73-year-old man presented with edematous crusted papules and nodules scarring with serous drainage on the scalp and upper trunk of several months' duration. Topics include considered that histopathology revealed a hypersensitivity reaction, and the clinicopathologic correlation that was believed to represent an arthropod bite reaction in the setting of CLL.

The intensification and expansion of agriculture is currently one of the greatest threats to biodiversity worldwide. Olive groves are one of the most extensive and diverse agroecosystems in the Mediterranean region. However, the efficiency of the methods used to sample arthropods in olive crops remains unclear. We compared the effectiveness of pan traps, sweep net and bait traps used to sample arthropods in olive groves. The pan traps collected 19 orders and 182 families, with an abundance that was 76% and 86% higher than that of sweep nets and bait traps, respectively. The composition of families differed significantly according to the method used; from a total of 234 families, 23% were sampled only by pan traps, 16% only by sweep net and 5% only by bait traps. The sampling method was the best predictor of arthropod abundance and number of families, followed by the vegetation and landscape diversity indexes. As pan trap, sweep net and bait trap methods do not obtain the same results when sampling arthropods, we recommend a combination of pan traps and a sweep net, depending on the goal of the studies and the arthropod groups targeted.

The invasion by alien macrophytes in aquatic ecosystems may produce a strong alteration of the native aquatic vegetation leading to heavy impacts for both plant and faunal native diversity. Myriophyllum aquaticum is an aquatic plant native of Southern America, invasive in several part of the world. We studied the effects of M. aquaticum invasion on plant and macro-arthropod communities in the canals around a protected wetland in the Mediterranean basin. We sampled plant and macro-arthropod communities in 10 transects in invaded and non-invaded tracts of the canals. We assessed the differences in plant and macro-arthropod species richness, diversity, taxonomic diversity and species composition between invaded and non-invaded habitats by means of univariate and multivariate analyses. Our study shows a significant loss of plant diversity between non-invaded to invaded sites, leading to communities numerically and taxonomically impoverished and highly divergent in the species composition. We also detected significant differences in arthropod species composition between invaded and non-invaded transects. Some taxa such as mosquitoes and malacostraca were more frequent in the M. aquaticum-dominated stands. Furthermore, the study shows a positive relation between invaded habitats and juvenile individuals of the invasive alien crayfish Procambarus clarkii. [ABSTRACT FROM AUTHOR]

The long coevolutionary history between sunflowers ( Helianthus annuus, Asterales: Asteraceae) and arthropods in the northern Great Plains has resulted in a commonly grown oilseed crop that harbors a large diversity of insects. A bioinventory of foliar and subterranean arthropods was performed in 22 sunflower fields over a period of three site years in central and eastern South Dakota. Overall, 467 morphospecies were collected. From foliage, 15 arthropod orders were observed. Those containing the greatest species diversity were Hymenoptera, Coleoptera, Hemiptera, Diptera and Araneae with 80; 53; 53; 40 and 30 morphospecies each, respectively. Subterranean arthropods from 19 orders were collected. The five orders containing the highest number of morphospecies were Coleoptera, Hymenoptera, Hemiptera, Araneae and Diptera containing 77; 17; 14; 11 and nine morphospecies respectively. Although bioinventories can be expensive and time consuming, information gathered from them has many uses, including efforts to assess the implications of pesticide use, wildlife conservation, land use- and climate-change on community structure in sunflowers. [ABSTRACT FROM AUTHOR]

In an era of biodiversity crisis, arthropods have great potential to inform conservation assessment and test hypotheses about community assembly. This is because their relatively narrow geographic distributions and high diversity offer high-resolution data on landscape-scale patterns of biodiversity. However, a major impediment to the more widespread application of arthropod data to a range of scientific and policy questions is the poor state of modern arthropod taxonomy, especially in the tropics. Inventories of spiders and other megadiverse arthropods from tropical forests are dominated by undescribed species. Such studies typically organize their data using morphospecies codes, which make it difficult for data from independent inventories to be compared and combined. To combat this shortcoming, we offer cyberdiversity, an online community-based approach for reconciling results of independent inventory studies where current taxonomic knowledge is incomplete. Participating scientists can upload images and DNA barcode sequences to dedicated databases and submit occurrence data and links to a web site (). Taxonomic determinations can be shared with a crowdsourcing comments feature, and researchers can discover specimens of interest available for loan and request aliquots of genomic DNA extract. To demonstrate the value of the cyberdiversity framework, we reconcile data from three rapid structured inventories of spiders conducted in Vietnam with an independent inventory (Doi Inthanon, Thailand) using online image libraries. Species richness and inventory completeness were assessed using non-parametric estimators. Community similarity was evaluated using a novel index based on the Jaccard replacing observed with estimated values to correct for unobserved species. We use a distance-decay framework to demonstrate a rudimentary model of landscape-scale changes in community composition that will become increasingly informative as additional inventories participate. With broader adoption of the cyberdiversity approach, networks of information-sharing taxonomists can more efficiently and effectively address taxonomic impediments while elucidating landscape scale patterns of biodiversity. [ABSTRACT FROM AUTHOR]

An accessible workflow is presented to create interactive, rotational scanning electron micrographs (rSEM). These information-rich animations facilitate the study and communication of complex morphological structures exemplified here by male arthropod genitalia. Methods are outlined for the publication of rSEMs on the web or in journal articles as SWF files. Image components of rSEMs were archived in MorphBank to ensure future data access. rSEM represents a promising new addition to the toolkit of a new generation of digital taxonomy. [ABSTRACT FROM AUTHOR]

Most eukaryotic organisms are arthropods. Yet, their diversity in rich terrestrial ecosystems is still unknown. Here we produce tangible estimates of the total species richness of arthropods in a tropical rainforest. Using a comprehensive range of structured protocols, we sampled the phylogenetic breadth of arthropod taxa from the soil to the forest canopy in the San Lorenzo forest, Panama. We collected 6144 arthropod species from 0.48 hectare and extrapolated total species richness to larger areas on the basis of competing models. The whole 6000-hectare forest reserve most likely sustains 25,000 arthropod species. Notably, just 1 hectare of rainforest yields >60% of the arthropod biodiversity held in the wider landscape. Models based on plant diversity fitted the accumulated species richness of both herbivore and nonherbivore taxa exceptionally well. This lends credence to global estimates of arthropod biodiversity developed from plant models. [ABSTRACT FROM AUTHOR]

The Australian curculionid Oxyops vitiosa Pascoe was introduced into Florida in 1997 as a biological control agent of the invasive tree Melaleuca quinquenervia (Cav.) S. T. Blake. Populations of the weevil increased rapidly and became widely distributed throughout much of the invasive tree's adventive distribution. In this study we ask if O. vitiosa has acquired natural enemies in Florida, how these enemies circumvent the protective terpenoid laden exudates on larvae, and what influence 1 of the most common natural enemies has on O. vitiosa population densities? Surveys of O. vitiosa populations and rearing of field-collected individuals resulted in no instances of parasitoids or pathogens exploiting weevil eggs or larvae. In contrast, 44 species of predatory arthropods were commonly associated (>5 individuals when pooled across all sites and sample dates) with O. vitiosa . Eleven predatory species were observed feeding on O. vitiosa during timed surveys, including 6 pentatomid species, 2 formicids and 3 arachnids. Species with mandibulate or chelicerate mouthparts fed on adult stages whereas pentatomids, with haustellate beaks, pierced larval exoskeletons thereby bypassing the protective larval coating. Observations of predation were rare, with only 8% of timed surveys resulting in 1 or more instances of attack. Feeding by the pentatomid Podisus mucronatus Uhler accounted for 76% of all recorded predation events. Podisus mucronatus numerically responded to fourth instars but no response was observed for other life stages. Damage to M. quinquenervia plants from feeding by O. vitiosa , however, was not influenced by P. mucronatus densities, indicating that predation does not alter plant suppression. [ABSTRACT FROM AUTHOR]

We compiled 109 species richness-altitude (SRA) relationships in arthropods to test the hypothesis that identification of shape and robustness of pattern are contingent on the selection of studies included in meta-analysis. We used attributes of their sampling design to distinguish three subsets of data according to stringent, intermediate, and lax selection criteria. We tested (1) whether uncertainty over identification of shape increases as the criteria of inclusion of studies relaxes and (2) whether studies that conform to stringent selection criteria show robustness in SRA patterns to variation in method used to identify shape. We identified the shape of each SRA relationship using statistical and visual methods; data sets that suggested several shapes as equally likely were sorted out by consensus. Arthropods suggested multiple forms in the SRA relationship, with predominance of hump-shaped patterns in the stringent subset. Uncertainty over identification of shape increased after application of intermediate and lax selection criteria. The method of analysis interacted with the quality of basic data to influence the relative distribution of patterns. We concluded that the gathering of large quantities of data is insufficient and that critical evaluation of literature is crucial to infer with confidence the general shape of ecological patterns in meta-anàlysis. [ABSTRACT FROM AUTHOR]

A catalogue of specimens belonging to the family Psychodidae (Diptera) deposited in the Medical Importance Arthropod Collection (CAIM) of the Instituto de Diagnóstico y Referencia Epidemiológicos (InDRE), Mexico is presented. In this collection the psychodids are represented by 2459 specimens of three subfamilies, six genera and 55 species. A total of 28 species are from 20 states of Mexico (Chiapas, Coahuila, Colima, Distrito Federal, Estado de Mexico, Guerrero, Jalisco, Michoacan, Morelos, Nayarit, Nuevo Leon, Oaxaca, Puebla, Quintana Roo, San Luis Potosi, Sonora, Tabasco, Tamaulipas, Veracruz, and Yucatan), and 27 species (172 specimens) proceed from other American countries like Argentina, Brazil, Costa Rica, United States of America, French Guiana, Honduras, Virgin Islands, Panama, Peru, Puerto Rico, Trinidad, and Venezuela. [ABSTRACT FROM AUTHOR]

The article discusses the findings of a study which investigated the potential of presence/absence models in the abundance of arthropods on Terceira Island in Azores. Researchers were able to collect presence/absence data for 48 arthropod species through the use of artificial neural networks, while probabilities of occurrence were evaluated from a standard arthropod survey program. Based on analysis of macroecological patterns, there is a weak tendency for spiders to exhibit probability of occurrence and local abundance.

1. Frequency of singletons – species represented by single individuals – is anomalously high in most large tropical arthropod surveys (average, 32%). 2. We sampled 5965 adult spiders of 352 species (29% singletons) from 1 ha of lowland tropical moist forest in Guyana. 3. Four common hypotheses (small body size, male-biased sex ratio, cryptic habits, clumped distributions) failed to explain singleton frequency. Singletons are larger than other species, not gender-biased, share no particular lifestyle, and are not clumped at 0·25–1 ha scales. 4. Monte Carlo simulation of the best-fit lognormal community shows that the observed data fit a random sample from a community of ~700 species and 1–2 million individuals, implying approximately 4% true singleton frequency. 5. Undersampling causes systematic negative bias of species richness, and should be the default null hypothesis for singleton frequencies. 6. Drastically greater sampling intensity in tropical arthropod inventory studies is required to yield realistic species richness estimates. 7. The lognormal distribution deserves greater consideration as a richness estimator when undersampling bias is severe. [ABSTRACT FROM AUTHOR]

Results of a year surveys in 21 houses from Puerto Vallarta, Mexico are provided. Details on the arthropod families are included. With the use of sticky traps, 25 197 specimens were collected. We recognized 122 families from 31 orders. Only five families grouped 76.45% of the observed abundance and the highest values of infestation indeces throughout the year: Entomobryidae (9.04%; 100%), Psyllopsocidae (10.10%; 95.23%), Liposcelididae (8.11%; 100%), Formicidae (33.58%; 100%) and Phoridae (15.42%; 100%). [ABSTRACT FROM AUTHOR]

1. In pine ecosystems, the role of the larval nests of the Mediterranean defoliator Thaumetopoea pityocampa as shelter of other arthropods, was studied for the first time. In Portugal, Pinus stands which differed in understorey plant diversity and level of attack by T. pityocampa were compared. 2. The arthropod fauna found sheltering inside the nests consisted of 60 species, representing 12 foraging types. Both arthropod richness and abundance were positively correlated with nest size, expressed as larval biomass. Arthropod richness was further positively correlated with understorey plant diversity, while no correlation was detected between arthropod richness and nest density. 3. Spiders accounted for up to 50% of the species richness, while 80% of the individuals collected were either juveniles, or females with brood, implying that T. pityocampa nests are used for overwintering and brood care. Seventy-six per cent of the Araneae were nocturnal ground foragers and specialised cryptic hunters, demonstrating the occurrence of indirect interactions among species belonging to different communities, namely ground vegetation layers and forest pine coppice. 4. It was concluded that, in Mediterranean pine ecosystems, T. pityocampa nests (i) create habitat diversification and contribute to improve overwintering survival of a wide range of arthropod species; (ii) play a functional role in the food web of pine ecosystems, by promoting indirectly mediated interactions among species from different communities; and (iii) do not contribute to create habitat for symtopic phytophagous arthropods, since contrary to literature references for different types of shelters, 98% of the associated species belonged to foraging types other than T. pityocampa. [ABSTRACT FROM AUTHOR]

Three different assemblages of cover crops were planted, fertilizer and herbicide input reduced, and mulch side-delivered in a northern Michigan tart cherry orchard to evaluate effects on tree leaf nutrients, arthropod communities, weed control, and tart cherry yield. The three treatments were compared against the conventional management system, which consisted of sod alleys and herbicide-maintained tree rows. Although fertilizer was reduced by 1/2 and herbicides eliminated in the ground cover management systems (GMSs), there was no evidence of reduced cherry yields. All GMSs provided more plant cover than the unmanipulated sod control. Biomass samples suggested that there was not enough side-delivery mulch to significantly reduce understory weed growth in the tree rows when compared to the non-mulched plots. The GMSs increased species richness, abundance, and diversity (H′) of arthropods, despite frequent pesticide applications in all treatments. The results of the economic analysis suggest that cover cropping, half N fertilizer, and herbicide elimination may be a viable alternative to conventional groundcover management in northern Michigan. [Copyright &y& Elsevier]

Species inventories are essential for documenting global diversity and generating necessary material for taxonomic study and conservation planning. However, for inventories to be immediately relevant, the taxonomic process must reduce the time to describe and identify specimens. To address these concerns for the inventory of arthropods across the Malagasy region, we present here a collaborative approach to taxonomy where collectors, morphologists and DNA barcoders using cytochrome c oxidase 1 (CO1) participate collectively in a team-driven taxonomic process. We evaluate the role of DNA barcoding as a tool to accelerate species identification and description. This revision is primarily based on arthropod surveys throughout the Malagasy region from 1992 to 2006. The revision is based on morphological and CO1 DNA barcode analysis of 500 individuals. In the region, five species of Anochetus (A. boltoni sp. nov., A. goodmani sp. nov., A. grandidieri, and A. madagascarensis from Madagascar, and A. pattersoni sp. nov. from Seychelles) and three species of Odontomachus (O. coquereli, O. troglodytes and O. simillimus) are recognized. DNA barcoding (using cytochrome c oxidase 1 (CO1)) facilitated caste association and type designation, and highlighted population structure associated with reproductive strategy, biogeographic and evolutionary patterns for future exploration. This study provides an example of collaborative taxonomy, where morphology is combined with DNA barcoding. We demonstrate that CO1 DNA barcoding is a practical tool that allows formalized alpha-taxonomy at a speed, detail, precision, and scale unattainable by employing morphology alone. [ABSTRACT FROM AUTHOR]

As part of the All Taxa Biodiversity Inventory (ATBI) in Great Smoky Mountains National Park (GSMNP). we have collected nearly 600 samples from soil/decomposed leaf litter, lichens and mosses on trees, and stream sediment and periphyton within all 19 permanent ATBI plots, with additional samples from caves, rock lichens, seeps, and bird nests. Tardigrades have been extracted from samples using centrifugation with Ludox AM™ and mounted on individual microscope slides in Hoyer's medium for identification under phase and DIC microscopy. Prior to our study, only three species of tardigrades had been reported from a few samples in the park. We have now examined over 9000 slides from 401 samples and recorded 73 species, 14 of which we believe may be new to science. Using Estimates 7.5 software for each of the major tardigrade habitats, we estimate a total species richness of ≈96 limno-terrestrial species in the park. In this paper, we discuss challenges inherent in tardigrade taxonomy and the need for revisions of species groups. [ABSTRACT FROM AUTHOR]

The loss of biotic integrity in ecosystems due to human pressure has been receiving much attention from the scientific community. The primary aim of this study is to understand how the increasing human pressure on natural forests in the Azorean archipelago (North Atlantic) is affecting their epigean arthropod communities and which biological parameters it affects most. An expert team did fieldwork covering most of the natural forests (mainly inside nature reserves) of the archipelago using standardized pitfall trapping. To build a multimetric index we tested a number of taxonomic and ecological parameters that can potentially be influenced by disturbance. Sixteen of these were found to be significantly influenced by disturbance in forests. We retained seven metrics due to both, desirable scalability properties and relatively low correlation between them. These included the percentages of endemic and predator species richness and also predator abundance, which are inversely related to disturbance; and the percentages of native and saprophagous species richness and introduced and herbivore abundance, which are positively related to disturbance. All seven metrics were combined in an Index of Biotic Integrity (IBI) value. We then proceeded to understand which potential disturbance factors are influencing the biotic integrity of communities and how such influence is felt. Five disturbance factors were found to influence the IBI, although in different ways: the size and fragmentation of reserves, the distance of sites to the reserve borders, the invasion by alien plants and the density of human paths at the sites. Given that only percentages of taxonomical or ecological characteristics were chosen as metrics, we tested and found the scalability of the IBI to be possible, allowing the comparison of sites with different collecting effort or even the comparison of reserves with different areas and numbers of collecting sites in each. Finally, we propose a novel graphical representation for multimetric indices like the IBI, one which allows retaining much of the information that is usually lost in multimetric indices. [ABSTRACT FROM AUTHOR]

The biodiversity in the sub-Antarctic region is threatened by climatic change and biological invasions, which makes the understanding of distributions of biotas on sub-Antarctic islands essential. Although the distribution patterns of vascular plants and insects on sub-Antarctic islands are well documented, this is not always the case for microarthropods. This study provides the first quantitative assessment of the distribution and abundance of microarthropods on Prince Edward Island (PEI), one of two islands in the Prince Edward Island group. Microarthropod community structure differed significantly between PEI and nearby Marion Island, with only two invasive alien species found on PEI compared with Marion Island. Furthermore, species richness, abundance and community structure differed significantly between habitat types on both islands. This study emphasizes the importance of quarantine measures when visiting PEI to maintain its status as one of the more pristine islands in the sub-Antarctic region. [ABSTRACT FROM AUTHOR]

Homeless people are particularly exposed to ectoparasite. The living conditions and the crowded shelters provide ideal conditions for the spread of lice, fleas, ticks, and mites. Body lice have long been recognized as human parasites and although typically prevalent in rural communities in upland areas of countries close to the equator, it is now increasingly encountered in developed countries especially in homeless people or inner city economically deprived population. Fleas are widespread but are not adapted to a specific host and may occasionally bite humans. Most common fleas that parasite humans are the cat, the rat, and the human fleas, Ctenocephalides felis, Xenopsylla cheopis, and Pulex irritans, respectively. Ticks belonging to the family Ixodidae, in particular, the genera Dermacentor, Rhipicephalus, and Ixodes, are frequent parasites in humans. Sarcoptes scabiei var. hominis is a mite ( Arachnida class) responsible for scabies. It is an obligate parasite of human skin. The hematophagic-biting mite, Liponyssoides sanguineus, is a mite of the rat, mouse, and other domestic rodents but can also bite humans. Finally, the incidence of skin disease secondary to infestation with the human bedbug, Cimex lectularius, has increased recently. Bacteria, such as Wolbacchia spp. have been detected in bedbug. The threat posed by the ectoparasite in homeless is not the ectoparasite themselves but the associated infectious diseases that they may transmit to humans. Except for scabies all these ectoparasites are potential vectors for infectious agents. Three louse-borne diseases are known at this time. Trench fever caused by Bartonella quintana ( B. quintana), epidemic typhus caused by Rickettsia prowazekii, and relapsing fever caused by the spirochete Borrelia recurrentis. Fleas transmit plague ( Xenopsylla cheopis and Pulex irritans), murine typhus ( Xenopsylla cheopis), flea-borne spotted rickettsiosis on account of the recently described species Rickettsia felis ( C. felis), and occasionally cat scratch disease on account of Bartonella henselae ( C. felis). The role of fleas as potential vector of B. quintana has recently been suggested. Among the hematophagic-biting mites, L. sanguineus, is responsible for the transmission of Rickettsia akari, the etiologic agent of rickettsialpox. Virtually, no data are available on tick-borne disease in this population. This article will deal with epidemiology, diagnosis, prevention, and treatment of these ectoparasite and the infectious diseases they transmit to the homeless people. [ABSTRACT FROM AUTHOR]

Sequence data derived from two mitochondrial markers, 16S rRNA and COI genes, were used to infer the evolutionary history of 47 insular and mainland populations covering most of the distributional range of the northeastern Mediterranean scorpion species Mesobuthus gibbosus. Based on the estimated divergence times of Mesobuthus lineages, the temporal frame of the genus differentiation in the northeastern Mediterranean region is placed in middle Miocene (15 million years ago). The biogeographic affinities of M. gibbosus populations point towards a mainly vicariant pattern of differentiation of the species which is consistent with the geological events that transformed the Aegean region during the period from 12 to 5 million years ago. M. gibbosus is an old northeastern Mediterranean species that has retained valuable bits of genetic information, reflecting some of the oldest vicariant events that have occurred in the area. Most importantly, the history witnessed by M. gibbosus has not been obscured by more recent palaeoevents of the region. Therefore, the case of M. gibbosus is in favour of a taxon-oriented ‘perception’ of the natural history of a given area. [ABSTRACT FROM AUTHOR]

The exotic Brazilian peppertree, Schinus terebinthifolius Raddi, is an invasive plant that readily displaces native vegetation and develops monospecific stands in central and south Florida's native ecosystems. Despite prior arthropod surveys of S. terebinthifolius in its adventive range, little is known concerning the acarofauna associated with the weed in Florida. Leaves of S. terebinthifolius also vary in the presence and development of domatia, which are small morphological structures that may benefit mites. We assessed the development of new mite associations with S. terebinthifolius in Florida and quantified within-plant distribution of these arthropods. Mites inhabited over one-third of the sampled leaves with greatest species diversity in the Prostigmata, followed by Mesostigmata, Astigmata, and Cryptostigmata, respectively. Fungivorous mites (dominated by Lorryia formosa) were the most common feeding guild, predatory mites were the most diverse, and herbivorous mites were rarely encountered during the survey. Interior leaves supported greater populations of mites than exterior leaves, whereas height of leaves in the canopy did not affect mite distributions. Foliar domatia varied in development and occurred on nearly two-thirds of the leaves sampled. More than three-quarters of all mites collected were found on domatia-bearing leaves, which supported three times more mites per leaf than leaves without domatia. Mite densities increased concomitantly with the number of domatia, while domatia development only affected tydeids and number of leaves had no effect. The potential influence of domatia-mediated, tritrophic interactions among existing predators and a potential biological control agent of S. terebinthifolius are discussed. [ABSTRACT FROM AUTHOR]

Background: In the spider Cupiennius salei about 30 groups of neural precursors are generated per hemi-segment during early neurogenesis. Analysis of the ventral neuromeres after invagination of the primary neural precursor groups revealed that secondary neural precursors arise during late embryogenesis that partially do not differentiate until larval stages. Results: In contrast to the primary groups, the secondary invaginating cells do not detach from each other after invagination but maintain their epithelial character and form so-called epithelial vesicles. As revealed by dye labeling, secondary neural precursors within epithelial vesicles do not show any morphological features of differentiation indicating that the formation of epithelial vesicles after invagination leads to a delay in the differentiation of the corresponding neural precursors. About half of the secondary neural precursor groups do not dissociate from each other during embryogenesis indicating that they provide neural precursors for larval and adult stages. Conclusions: Secondary neural precursors are arrested in an immature state by formation of epithelial vesicles. This mechanism facilitates the production of larval neural precursors during embryogenesis. I discuss the evolutionary changes that have occured during neural precursor formation in the arthropod group and present a model for the basal mode of neurogenesis. [ABSTRACT FROM AUTHOR]

Simple horizontal, planispiral burrows occur in Recent beach sediments on the south shore of Gander Lake, Newfoundland. The burrows apparently represent deposit feeding, possibly by an arthropod. This occurrence extends the known environmental range of such traces into lacustrine settings and illustrates that such behaviour is not exclusive to marine settings. [ABSTRACT FROM AUTHOR]

The paper proposes an overview of the endoskeletal structures of the head and trunk in the different arthropod groups: Chelicerata, Crustacea, Myriapoda and Hexapoda (=Insecta s.l.). Two major endoskeletal systems are reported with their cytological characteristics: those made up of connective tissue derived from muscular tendons, and those consisting of cuticular rods or plates arising from integumentary ingrowths. The morphological value of the various endoskeletal structures, their possible homologies in different groups, and their presumed evolutionary changes are discussed. This survey may be considered as a first step to use morphological characteristics of the endoskeleton in future cladistic analyses to assess the phylogeny of arthropods. [Copyright &y& Elsevier]

The article discusses the implications of Azadirachtin-exposure towards wolf spiders with regards to its mortality, growth and immunological function. For the investigation process, several spiders have been examined through allowing them to feed on prey that were exposed to various concentrations of azadirachtin. The results of the experimentation shows that the ingestion of azadirachtin-treated prey for several weeks have provided significant decrease in the tetrahydrocannabinol substances of female spiders, as well as on various growth parameters. It has been concluded that azadirachtin provides deleterious effects on species of beneficial arthropod which could contribute to the decrease of its population.

We report a new locality for Telmatobufo bullocki, a critically endangered amphibian endemic of Chile. This new location, Los Queules National Reserve, has high relevance on the conservation of this species because is the only known population in a protected area north of the Bio Bio River, situated in a region deeply modified for forestry and agriculture. Also, we included habitat descriptions and a detailed distribution map with all reported localities. [ABSTRACT FROM AUTHOR]

The biological performance of phytophagous organisms and bioregulators in an area of lysiloma for animal shade was studied to determine its influence on the balance between the phytophagous organisms and the bioregulators. The research was developed for three years in cattle rearing areas of the Institute of Animal Science in Cuba. The experimental procedure was the populational sampling of arthropods. A General Linear Model was used with the year and season factors for the data analysis. Also, the space distribution of the organisms was determined through the test of goodness of fit ÷². The results showed that Heteropsylla cubana and Empoasca sp are the phytophagous insects of highest incidence, although the values did not surpass 0.5 average individuals/m². Chrysoperla sp., Pheidole megacephala, Brachimeria sp., and Peucetia viridians were among the bioregulators. The season was not significant for the organisms under study. However, the year factor showed differences (P < 0.001), both for H. cubana and Empoasca sp. and for the bioregulators. The collected species of highest incidence had a space distribution of the Contagion Type. It is concluded that a scarce number of arthropod, phytophagous and beneficial species cohabitated in the area of Lysiloma bahamensis controlling pests and, thus, not producing economic harms. This performance may be related to the chemical composition of the plant, which should be demonstrated in further studies. It is recommended to promote the use of lysiloma as shade trees to improve the comfort of the animals, increase the biodiversity of the agroecosystems, and propitiate the biological stability. [ABSTRACT FROM AUTHOR]

The article presents information about glycine-rich antifreeze proteins from snow fleas. Snow fleas are primitive arthropods with six legs and no wings. Some species produce antifreeze proteins (AFPs) to help resist freezing. AFPs were purified from snow flea homogenate by two cycles of ice affinity purification, in which AFPs, which bind to the surface of ice, become incorporated into a slowly grown ice hemisphere. The homogenate produced an ice hemisphere that was cloudy and showed shaping of the ice crystals, whereas a hemisphere grown in buffer did not. The purified fraction was resolved into two peaks by reversed-phase high-performance liquid chromatography at pH 7.0. Snow flea AFPs were more active than a typical fish AFP, and the 6.5-kD AFP had activity comparable to that of an 8.4-kD beetle AFP. Crystals formed with the 15.7-ku AFP were indistinguishable from those made in a crude homogenate, whereas those formed with the 6.5-kD AFP were similar but less elongated. Fish may have acquired AFPs during the recent Cenozoic glaciations in the polar regions, but the events that drove antifreeze production in arthropods are uncertain.