Arthropods Spiders Ecology Ethology Biological Sciences

Arthropoda berasal dari bahasa Yunani, yaitu arthro yang berarti ruas dan podos yang berarti kaki. Jadi, Arthropoda berarti hewan yang kakinya beruasruas. Hewan ini memiliki jumlah spesies yang saat ini telah diketahui sekitar 900.000 spesies. Contoh anggota filum ini antara lain kepiting, udang, serangga, laba-laba, kalajengking, kelabang, dan kaki seribu, serta spesies-spesies lain yang dikenal hanya berdasarkan fosil.

The life history of Theridion incanescens Simon, 1890 is studied for the first time in
Egypt. T. incanescens was first recorded from Egypt in 2012. It was collected from Aloe
vera cultivated in Giza, mango, citrus and grape trees at El-Sharqia & Ismalia. The
individuals were reared under laboratory conditions and were fed every two days on
motile stages of Tetranychus urticae (Koch, 1836) until reaching to subadults, after that
they were fed on Ceratitis capitata (Wiedemann). The males and females reached
maturity in the fifth instar after 41–47 & 34–52 days respectively. Adult longevity, life
span, fecundity of female and food consumption were studied too. The mating behaviour
of T. incanescens was described. It began with courtship followed by four copulatory
sequences. Total duration of the mating behaviour was 3:05 hour.

L’homme est le seul animal à faire partie du temps et, en même temps, à en être en dehors. C’est pour cela qu’il a eu la possibilité d’inventer une dimension temporelle propre. Les groupes humains donnent forme à cette capacité d’inventer le temps à travers les chrono-architectures, c’est-à-dire des “espaces de sens durable” socialement partagés. Chaque groupe humain, en habitant ces espaces-temps donne un rythme à la vie sociale en conservant la mémoire collective, en organisant la vie quotidienne, en élargissant l’horizon du sens du futur, en permettant, en bref, au monde social d’exister. Les architectures du temps social sont pour cette raison une des technologies les plus sophistiquées qui existent, tout en étant perçues comme la chose la plus naturelle. Qu’arrive-t-il alors à cette capacité humaine d’inventer le temps une fois qu’elle est englobée et accélérée mondialement par une seule chrono-sphère technique ? La thèse que nous chercherons à développer est que la compression de l’espace de relation entre temporalité et imaginaire est en train de pousser la créativité humaine vers la réactivité animale et de pousser les mondes sociaux à s’organiser selon une logique propre aux super-organismes. Nous montrerons ce retour involontaire à une condition pré-humaine comme l’effet feedback généré par l’époque post- humaine.

La complejidad estructural (número de elementos estructurales por unidad de área,tales como plantas, rocas o detrito) se ha señalado como un factor importante en la
dinámica poblacional y trófica de los artrópodos terrestres. Para los artrópodos depredadores, como las arañas tejedoras orbiculares (Araneidae y Tetragnathidae) se ha observado una relación positiva entre la complejidad estructural y su abundancia.
Existen pocos estudios que evalúen los efectos de la complejidad estructural con un enfoque multitrófico, es decir considerando a los depredadores, consumidores primarios y productores primarios.
En este trabajo se evaluó el efecto de la complejidad estructural en la influencia de las arañas tejedoras orbiculares Argiope trifasciata (Araneidae), Neoscona oaxacensis (Araneidae) y Leucauge sp.
(Tetragnathidae) sobre los niveles tróficos inferiores (Pennisetum clandestinum Poaceae y la comunidad de artrópodos fitófagos asociada) en los pastizales inducidos
de la Reserva Ecológica del Pedregal de San Ángel (REPSA). Para ello se realizó un experimento de campo colocando parcelas control y tres tratamientos de incremento
de la complejidad estructural (varas secas de Dodonaea viscosa, ramas secas de la misma planta y huacales) en los pastizales inducidos. En estas parcelas se introdujeron individuos de las tres especies de arañas y se monitoreó su abundancia, el tamaño de las redes y las presas consumidas (29 de agosto al 10 de noviembre de 2011). También se evaluó la estructura de la comunidad de artrópodos (riqueza,
abundancia, diversidad y biomasa) y el daño foliar de P. clandestinum en tres fechas distintas, así como su biomasa al final del experimento. Se esperaba un efecto descendente llamado cascada trófica, en el que al aumentar la complejidad
estructural, se incrementara el establecimiento de arañas y la regulación de los herbívoros por parte de éstas, con la consecuencia de una mayor biomasa de pasto y un menor daño foliar en el mismo.
La complejidad estructural afectó significativamente a la abundancia, biomasa, tamaño de las redes y número de
presas de las arañas registrándose valores mayores el tratamiento de ramas secas de D. viscosa probablemente debido a una mayor eficiencia de caza por parte de las arañas al obtener un mayor número de sitios de anclaje disponibles para las redes debido al tratamiento. No se observaron efectos significativos de la complejidad estructural en la estructura de la comunidad de artrópodos (con excepción de la diversidad H'), así como en la biomasa y daño foliar de P. clandestinum, probablemente debido a otros factores como el
tiempo de experimento, el bajo consumo de presas en relación al total de éstas en la parcela, el tipo de herbívoro dominante y el método usado para cuantificar el daño
foliar entre otros.

1. Consistent behavioural differences between individuals have far-reaching implications for ecology and evolution, including how populations cope with increasing anthropogenic changes, notably pesticides. Although sublethal doses of insecticides are known to alter behaviour, current studies on the relationship between toxicants and behaviour tend to ignore effects on individual variation.
2. Our objective was to determine whether sublethal exposure to an organophosphate insecticide could affect the consistency of individual behaviour and disrupt behavioural correlations, in a jumping spider occurring in agroecosystems. Adults of the jumping spider Eris militaris (Araneae: Salticidae) were scored by an open-field and a prey-capture assay, each conducted as pre- and post-insecticidal exposure to the organophosphate phosmet. Half of the individuals received no exposure to the insecticide to provide a control group. We then estimated the changes in repeatability, a measure of the extent of personality differences, and in behavioural correlations between control and insecticide-treated groups.
3. Although insecticide exposure had no discernable effects on the population’s average behaviours, insecticide-exposed individuals showed an average of 23 % lower repeatability and the correlation between activity and prey capture was more strongly collapsed in females.
4. Our results provide clear evidence that exposure to sublethal doses of insecticides on an important arthropod predator in agroecosystems causes substantial alteration of personality differences even in absence of a population-wide shift in behaviour. This suggests insecticide effects are more complex than previously thought and indicates high variation in the way individuals coped with insecticidal exposure.
5. By altering the consistency of behavioural traits and their correlations, exposure to sublethal concentrations of insecticides can have subtle effects on behavioural expression, which may ultimately affect biocontrol performance in an important arthropod predator in agroecosystems. Our study calls for an increasing focus on individual behavioural variation when testing the effects of pesticides on non-targeted fauna.

Sustained nitrogen (N) deposition has a wide-ranging impact on terrestrial ecosystems. However, still little attention has been paid to responses of urban soil fauna to the increasing N deposition. To clarify such effects on the soil properties and soil fauna in typical urban lawns (featuring Cynodon dactylon vegetation), a control experiment was conducted for 1 year, in which NH 4 NO 3 was added as the external N source with four treatments of N addition: N0 (i.e., only water), N1 (50 kg N ha 1 yr 1), N2 (100 kg N ha 1 yr 1), N3 (150 kg N ha 1 yr 1). Results showed that N additions influence soil faunal communities in the urban lawns soil. The relative abundance of Oribatida increased with the N treatment level, partially replacing the more sensitive Collembola. Significant differences in the Shannon-Wiener and Margalef indices (p < 0.01) supported this statement. Although higher doses of N addition showed adverse effects on soil fauna communities, low N inputs increased the soil fauna diversity and richness, especially at 5-10 cm depth. A threshold effect appears to exist: low N addition (<25 kg N ha 1) did not negatively affect pedofauna structure and composition, while in the range from these values up to 50 kg N ha 1 , the composition of the soil fauna underwent major changes which were confirmed by the decline of biodiversity indices. These changes are accompanied by the decreased pH values with increasing N inputs.

The Atlantic Forest is one of the key biodiversity hotspots in the world. Its understory can
be dominated by species such as the native bamboo Chusquea ramosissima (tacuarembó),
which can be an aggressive gap colonizer and change biotic and abiotic conditions compared
to mature forest. A strong association has been observed between Salticidae spiders and
microhabitat type, frequently linked to host plant structure. Since little is known about the
diversity of spiders in tree-fall gaps of the Atlantic Forest, the differences in the Salticidae
assemblages between three habitats –the understory of typical forest, Bamboo gaps
(dominated by tacuarembó) and restoration areas (tacuarembó removal)– were explored in
the southern tip of the Atlantic Forest, Upper Parana Atlantic Forest ecoregion in Misiones
province, Argentina. A total of 515 jumping spiders (32 species; 106 adults) were collected.
Differences in species composition were detected between habitats, where Forest understory
and Bamboo gaps differ in almost 50% of the species. Bamboo gaps had the highest number
of exclusive species, but the three habitats did not differ in their average taxonomic diversity
indices. In addition, richness was higher in Bamboo gaps compared to Forest understory,
which may reflect higher niche diversity in the former habitat.

Se reporta por primera vez a Euagrus leones Coyle, 1988 dentro del Estado de México, anteriormente reportado únicamente para el D. F.
 
We reported to first time Euagrus leones Coyle, 1988 into Estado de Mexico, previously only reported in the Park Desierto de los Leones. D.F.

Arthropods account for more than 65% of global species and 85% of animal species. On a temperate grassland, arthropods hold a huge biomass (1,000kg/ha), seconded to plant (20,000kg/ha) and microorganisms (7,000kg/ha) but much higher than mammals (1.2kg/ha), birds (0.3kg/ha), and nemantodes (120kg/ha). Arthropods play the role of both pests and beneficial organisms. Some arthropods are important crop pests but others are natural enemies. Some arthropods are important health pests but many crustaceans are important food sources of humankinds. Arthropods govern the structures and functions of natural ecosystems, but are always ignored by researchers. On the global scale, the surveys of mammals, birds and vascular plants were relatively perfect because they were economically important and easily surveyed. However, arthropods, despite their ecological and economical importance, have not yet been fully surveyed and recorded due to their difficulties to be sampled. The research on arthropods must be further promoted. The journal, Arthropods, is inaugurated to provide a public and appropriate platform for the publication of studies and reports on arthropods.

ARTHROPODS (ISSN 2224-4255) is an international journal devoted to the publication of articles on various aspects of arthropods, e.g., ecology, biogeography, systematics, biodiversity (species diversity, genetic diversity, et al.), conservation, control, etc. The journal provides a forum for examining the importance of arthropods in biosphere (both terrestrial and marine ecosystems) and human life in such fields as agriculture, forestry, fishery, environmental management and human health. The scope of Arthropods is wide and embraces all arthropods-insects, arachnids, crustaceans, centipedes, millipedes, and other arthropods. Articles/short communications on new taxa (species, genus, families, orders, etc.) and new records of arthropods are particularly welcome.

Authors can submit their works to the email box of this journal, arthropods@iaees.org. All manuscripts submitted to this journal must be previously unpublished and may not be considered for publication elsewhere at any time during review period of this journal. Authors are asked to read Author Guidelines before submitting manuscripts.

In addition to free submissions from authors around the world, special issues are also accepted. The organizer of a special issue can collect submissions (yielded from a research project, a research group, etc.) on a specific research topic, or submissions of a scientific conference for publication of special issue.

Arthropods 
ISSN 2224-4255
URL: http://www.iaees.org/publications/journals/arthropods/online-version.asp
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E-mail: arthropods@iaees.org
Editor-in-Chief: WenJun Zhang