Arthropods

Observations of wound healing and regeneration of walking legs in specimens of Nymphon australe Hodgson, 1902, Nymphon charcoti Bouvier, 1911, Colssendeis tortipalpus Gordon, 1932 and Pentapycnon charcoti Bouvier 1910 archived in the U. S. National Museum of Natural History collections is reported. One hundred and ninety-four specimens of N. australe were analyzed for evidence of regeneration. Blastema formation and or regenerated limbs of reduced size were found in 64 individuals, 38%. Forty-four specimens of N. charcoti were analyzed for evidence of regeneration. A blastema and/or regenerated limbs of reduced size were found in 12 individuals, 27%. Fifteen specimens of Colssendeis tortipalpus were analyzed for evidence of regeneration. Five individuals, 33%, had either a fully regenerated walking leg of reduced size or a blastema was present. Ten individuals of Pentapycnon charcoti were analyzed for evidence of regeneration. None of these animals showed signs of regeneration. The ...

Changes in ecosystem functions following disturbances are of central concern in ecology and a challenge for ecologists is to understand the factors that affect the resilience of community structures and ecosystem functions. In many forest ecosystems, one such important natural disturbance is fire. The aim of this study was to understand the variation of resilience in six functional groups of invertebrates in response to different fire frequencies in southern Switzerland. We measured resilience by analysing arthropod species composition, abundance and diversity in plots where the elapsed time after single or repeated fires, as determined by dendrochronology, varied. We compared data from these plots with data from plots that had not burned recently and defined high resilience as the rapid recovery of the species composition to that prior to fire. Pooling all functional groups showed that they were more resilient to single fires than to repeated events, recovering 6–14 years after a single fire, but only 17–24 years after the last of several fires. Flying zoophagous and phytophagous arthropods were the most resilient groups. Pollinophagous and epigaeic zoophagous species showed intermediate resilience, while ground-litter saprophagous and saproxylophagous arthropods clearly displayed the lowest resilience to fire. Their species composition 17–24 years post-burn still differed markedly from that of the unburned control plots. Depending on the fire history of a forest plot, we found significant differences in the dominance hierarchy among invertebrate species. Any attempt to imitate natural disturbances, such as fire, through forest management must take into account the recovery times of biodiversity, including functional group composition, to ensure the conservation of multiple taxa and ecosystem functions in a sustainable manner.

Chemical communication is virtually universal among terrestrial and aquatic organisms. Chemical signals control the interactions of cells and organs (hormones) as well as the intra-(pheromones) and interspecific (allelochemicals) relationships between animals. The review considers three examples for chemical communication in insects and other arthropods on different hierarchic levels of biological organization, from the intraindividual level, where hormones control development and reproduction of the animals, to the interspecific level, where semiochemicals function as defense agents against predators or may be used for finding and recognizing food resources. Knowledge of the function of these systems and of the molecular structures of the chemical compounds involved may provide the basis for highly selective techniques of pest control. * This paper was prepared as an overview of a symposium session presented at "Animals and Environments," the Third International Conference for Comparative Physiology and Biochemistry, Ithala Game Reserve, KwaZulu-Natal, South Africa, 2004 (http://www.natural-events.com/ithala/default-follow_2.asp).

Understanding animal terrestrialization, the process through which animals colonized the land, is crucial to clarify extant biodiversity and biological adaptation. Arthropoda (insects, spiders, centipedes and their allies) represent the largest majority of terrestrial biodiversity. Here we implemented a molecular palaeobiological approach, merging molecular and fossil evidence, to elucidate the deepest history of the terrestrial arthropods. We focused on the three independent, Palaeozoic arthropod terrestrialization events (those of Myriapoda, Hexapoda and Arachnida) and showed that a marine route to the colonization of land is the most likely scenario. Molecular clock analyses confirmed an origin for the three terrestrial lineages bracketed between the Cambrian and the Silurian. While molecular divergence times for Arachnida are consistent with the fossil record, Myriapoda are inferred to have colonized land earlier, substantially predating trace or body fossil evidence. An estimat...

The application of DNA barcoding to dietary studies allows prey taxa to be identified in the absence of morphological evidence and permits a greater resolution of prey identity than is possible through direct examination of faecal material. For insectivorous bats, which typically eat a great diversity of prey and which chew and digest their prey thoroughly, DNAbased approaches to diet analysis may provide the only means of assessing the range and diversity of prey within faeces. Here, we investigated the effectiveness of DNA barcoding in determining the diets of bat species that specialize in eating different taxa of arthropod prey. We designed and tested a novel taxon-specific primer set and examined the performance of short barcode sequences in resolving prey species. We recovered prey DNA from all faecal samples and subsequent cloning and sequencing of PCR products, followed by a comparison of sequences to a reference database, provided species-level identifications for 149 ⁄ 207 (72%) clones. We detected a phylogenetically broad range of prey while completely avoiding detection of nontarget groups. In total, 37 unique prey taxa were identified from 15 faecal samples. A comparison of DNA data with parallel morphological analyses revealed a close correlation between the two methods. However, the sensitivity and taxonomic resolution of the DNA method were far superior. The methodology developed here provides new opportunities for the study of bat diets and will be of great benefit to the conservation of these ecologically important predators.

Various functions have been proposed for the 40-50 independent origins of bioluminescence across the tree of life-for example, mate recognition, prey attraction, camouflage, and warning coloration . Millipedes in the genus Motyxia produce a greenish-blue bioluminescence at a wavelength of 495 nm that can be seen in darkness . These detritivores are chemically defended by cyanide, which they generate internally and discharge through lateral ozopores . Motyxia are blind, and thus provide an ideal model system to investigate the ecological role of bioluminescence since discrimination of their visual appearance is limited to other organisms, for example predators. Detailed studies have been made of the biochemical mechanisms underlying Motyxia bioluminescence . In contrast, the adaptive significance of the bioluminescence in these millipedes remained unknown . We show that bioluminescence has a single evolutionary origin in millipedes and it serves as an aposematic warning signal to deter nocturnal mammalian predators. Contrary to the intuitive expectation that luminescence might attract curious predators, we obtained strong experimental evidence in field trials that luminescence deters predation attempts, with living and artificial non-luminescent millipedes being attacked up to four times more often than their luminescent counterparts. Among the numerous examples of bioluminescence, this is the first field experiment in any organism to demonstrate that bioluminescence functions as a warning signal.

The fynbos of South Africa is renowned for its high richness of plant species, many of which are insect- pollinated. We conducted a visual survey of arthropod activity to examine how environmental factors influence activity patterns across the biome. We estimated the activity of moving medium- to large-sized Hymenoptera, Diptera, Lepidoptera and Coleoptera using an abundance-weighted presence score. Broken stick regression analysis shows that insect activity increased with ambient air temperatures to between 22 and 30 °C and then stabilized in the case of Hymenoptera, or decreased for Diptera, Lepidoptera and Coleoptera. There was also a clear negative impact of wind speed on arthropod activity. Insect activity across the biome was poorly explained by landscape temperature and rainfall variables, and was instead  best explained by flower availability. A summer-autumn survey observed greater insect activity with no within-month variation, while the transition from winter to spring for the winter-spring survey saw more insect activity associated with the later months. More detailed studies of activity in the fynbos are needed at the species level, as predicted climate change impacts on temperature suggest likely consequences for  plant-pollinator interactions, agricultural pest species, and arthropod-predator interactions.

As in Lymnaea stagnalis NPY plays a key role in regulating energy flows but has no effect on food intake, two important questions arise: 1) How is the amount of food consumed related to energy storage? 2) Can we give a molecular explanation for this alteration in function of NPY during evolution? Recent data have shown that also in Lymnaea a leptin-like factor is produced by glycogen storing cells which inhibits food intake, a Lymnaea storage feedback factor (LySFF). So, food consumption seems in balance with the amount of energy stored in this animal. We suppose that NPY neurons in Lymnaea have receptors for LySFF so that their activity in regulating energy homeostasis reflects the amount of stored energy. By comparing the molecular structure of NPYs in invertebrates it became clear that only molluscan and arthropod NPY are synthesized from a prohormone similar to vertebrate NPYs and should be considered as real invertebrate homologs of NPY. Based on pharmacological data we suppose that the identified Lymnaea NPY receptor is a Y1 subtype. This might explain that LyNPY has no effect on food intake in Lymnaea as this function of NPY in mammals is regulated through the Y5 subtype receptor.

We describe a new stylonurid eurypterid from the evaporitic potassium-salt deposits of the Upper Devo-nian (Famennian) Soligorsk Formation in the Pripyat Trough of Belarus. All specimens are assigned to Soli-gorskopterus tchepeliensis new genus new species, which represents the first formally described eurypterid species from Belarus. The occurrence of well-preserved eurypterids in these unusual evaporite deposits is most likely due to transport from freshwater stream habitats into a hypersaline setting following death. Soligorskopterus tchepeliensis n. gen. n. sp. appears to be intermediate between the traditionally considered parastylonurids and stylonurids and thus extends our understanding of stylonurid evolution in the mid-Paleozoic. Soligorskopterus n. gen. extends the occurrence of Famennian eurypterids into eastern Laurussia and the Stylonuridae into the Upper Devonian, and this taxon could be part of a global eurypterid habitat shift that took place in the Late Devonian.

Concentrations of arsenic, cadmium, copper, lead, and nickel were measured in soils, house mice (Mus musculus), and the main food items of this omnivorous mouse to examine the occurrence of these metals in selected components of a seasonal wetland. Soil concentrations of copper, lead, and (in some areas) nickel were elevated, but extractable soil concentrations indicated low bioavailability of metals. Levels of most metals in mice and composited arthropods were consistent with reference site concentrations from other studies. However, copper was found to be particularly mobile within the local ecosystem and accumulated in house mouse carcasses and composited arthropods at substantial levels. Metal residues in Scirpus robustus (alkali bulrush) roots exceeded those in seeds, consistent with patterns of bioaccumulation commonly observed in plants. Uptake and bioaccumulation factors for S. robustus seeds and roots, arthropods, and mouse carcasses and livers are reported. Concentrations of lead and nickel in S. robustus roots exhibited significant linear relationships with levels in soils. Copper levels in S. robustus seeds varied significantly with those in house mouse livers, suggesting that trophic transfer of copper from this food source to mice occurred. However, other spatial patterns of bioaccumulation in S. robustus and house mice relative to soil/seed concentrations were absent. Metal levels in house mice bore no relation to body weight or estimated age.

This study compares the number of individuals of the hunting and web-building guilds of spiders collected at the dry grassland and gallery forest of the Chapada Diamantina, State of Bahia. There was no difference between the number of individuals collected in the dry grassland (n = 39) and the gallery forest (n = 40), but the number of individuals of each guild was significantly different between the sampled areas. Individuals of the spider web-building guild prevailed in the gallery forest (n = 27), while those from the hunting guild prevailed in the dry grassland (n = 24). The importance of the microhabitats to the distribution and composition of spiders' guild are discussed.

Xiphosurids are an archaic group of aquatic chelicerate arthropods, generally known by the colloquial misnomer of ‘horseshoe crabs’. Known from marine envi- ronments as far back as the early Ordovician, horseshoe crabs are generally considered ‘living fossils’ – descendants of a bradytelic lineage exhibiting little morphological or ecological variation throughout geological time. However, xiphosurids are known from freshwater sediments in the Palaeozoic and Mesozoic; furthermore, the contention that xiphosurids show little morphological variation has never been tested empirically. Attempts to test this are hampered by the lack of a modern phylogenetic framework with which to explore different evolutionary scenarios. Here, I present a phylogenetic analysis of Xiphosurida and explore patterns of morphospace and environmental occupation of the group throughout the Phanerozoic. Xiphosurids are shown to have invaded non-marine environments indepen- dently at least five times throughout their evolutionary history, twice resulting in the radiation of major clades – bellinurines and austrolimulids – that occupied novel regions of morphospace. These clades show a convergent ecological pattern of differentiation, speciation and subse- quent extinction. Horseshoe crabs are shown to have a more dynamic and complex evolutionary history than previ- ously supposed, with the extant species representing only a fraction of the group’s past ecological and morphological diversity.

Today, there is a trend in research to return to plant extracts as remedies against endo-and ectoparasites. Many daily appearing papers describe the efficacy of different plant extracts. However, the second step, to develop a product for the market (that could settle obvious needs), is in general not done. Thus, many results will be forgotten soon and the work was done in vain. The present review shows in examples that very efficacious biocidal and repellent products were developed from extracts of the plants Vitex agnus castus, Azadirachta indica, and from others which produce etheric oils. Of course, it is needed that the extracts have to be tested seriously for their activity, non-toxicity, tolerability, and user compliance. However, the selected examples show that it is worthwhile to consider plants in the fight against endo-and ectoparasites. List 18 contains compounds which act as insecticides or acarizides-their number is also reduced.

The maxilliped venom claw is an intriguing structure in centipedes. We address open questions concerning this structure. The maxillipeds of fossil centipedes from the Carboniferous (about 300 million years old) have been described, but not been depicted previously. Re-investigation demonstrates that they resemble their modern counterparts. A Jurassic geophilomorph centipede (about 150 million years old) was originally described as possessing a rather leg-like maxilliped. Our re-investigation shows that the maxilliped is, in fact, highly specialized as in modern Geophilomorpha. A scenario for the evolution of the centipede maxilliped is presented. It supports one of the two supposed hypotheses of centipede phylogeny, the Pleurostigmophora hypothesis. Although this hypothesis appears now well established, many aspects of character evolution resulting from this phylogeny remain to be told in detail. One such aspect is the special joint of the maxilliped in some species of Cryptops. Cry...

Food security in West Africa could be improved if basic taxonomic information about pests and biocontrol agents was readily available for the region. Because predatory ladybeetles have been important elements in pest management programs in other regions of the world, we reviewed the literature, conducted field surveys, and visited natural history museums in order to produce a catalogue of the Coccinellidae (Coleoptera) of West Africa. The catalogue includes 250 species representing 38 genera and 18 tribes, as well as summaries of available biological and distributional data.

The digestive system of several species of sea spiders (Pycnogonida, Arthropoda) was studied by electron microscopy. It is composed of the foregut inside a long proboscis, a midgut and a hindgut. Lips near the three jaws at the tip of the proboscis receive several hundred ductules originating from salivary glands. These previously undetected glands open on the lips, a fluted, projecting ridge at the external hinge line of the jaws, i.e., to the outside of the mouth. This disposition suggests affinities to the chelicerate line. The trigonal esophagus within the proboscis contains a complex, setose filter device, operated by dedicated muscles, that serves to reduce ingested food to subcellular dimensions. The midgut has diverticula into the bases of all legs. Its cells differentiate from the basal layer and contain a bewildering array of secretion droplets, lysosomes and phagosomes. In the absence of a hepatopancreas, the midgut serves both digestive and absorptive functions. The cuticle-lined hindgut lies in the highly reduced, peglike abdomen.

Arthropods
ISSN 2224-4255
[email protected]

Volume 9, Number 4, 1 December 2020

Cover Pages

[Front Pages (142K)] [Back Pages (63K)]
Articles

Biochemical characterization of digestive carbohydrases in Moroccan locust, Dociostaurus maroccanus Thunberg (Orthoptera: Acrididae)
Arthropods, 2020, 9(4): 119-128
Bahareh Rafiei, Mohammad Ghadamyari, Sohrab Imani, et al.
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Wing characters for morphological study on the honey bee (Apis mellifera L.) populations among six provinces of Iran
Arthropods, 2020, 9(4): 129-138
Shahram Dadgostar, Jamasb Nozari, Gholamhossein Tahmasbi
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Morpho-taxonomic study of some planktonic caught megalopal stages collected from northern Arabian Sea
Arthropods, 2020, 9(4): 139-154
Muhammad Aslam
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Microhabitat preference and biology of Holconia insignis (Thorell, 1870) (Araneae:Sparassidae) in banana plantation agroecosystem
Arthropods, 2020, 9(4): 155-163
Akamu Jude Ewunkem, Christophe Parr Mbua, Nelson Neba Ntonifor
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Latitudinal gradient in species richness of Sphaerotherium
Arthropods, 2020, 9(4): 164-170
Mark Cooper
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First record of some jumping spiders (Arachnida: Araneae: Salticidae) from Pench National Park, Maharashtra State, India
Arthropods, 2020, 9(4): 171-174
Pawan U. Gajbe
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Ninety-eight Mexican free-tailed bats, Tadarida brasiliensis mexicana, collected from 4 locations in Mexico between November 1996 and June 1998, were examined for metazoan parasites. Twenty-one parasitic taxa belonging to 3 phyla (Plathyhelminthes, Nematoda, and Arthropoda) were recovered including 5 helminth taxa (3 digenean, 1 cestode, and 1 nematode) and 16 arthropod taxa (12 mite, 2 tick, and 2 insect). The digenean Ochoterenatrema labda was the most prevalent and abundant helminth in collections from the states of Puebla, Zacatecas, and Durango. Urotrema scabridum and Dicrocoelium rileyi reached the highest values of prevalence and mean abundance of infection in Nuevo León state. Among arthropod taxa recovered, Chiroptonyssus robustipes was the most prevalent and abundant parasite in all 4 localities, and its nymphal stage was the most abundant form recovered. In total, 10 new host and 43 locality records are presented.

Dichotomous keys that follow a single pathway of character state choices to an end point have been the primary tools for the identification of unknown organisms for more than two centuries. However, a revolution in computer diagnostics is now under way that may result in the replacement of traditional keys by matrix-based computer interactive keys that have many paths to a correct identification and make extensive use of hypertext to link to images, glossaries, and other support material. Progress is also being made on replacing keys entirely by optical matching of specimens to digital databases and DNA sequences. These new tools may go some way toward alleviating the taxonomic impediment to biodiversity studies and other ecological and evolutionary research, especially with better coordination between those who produce keys and those who use them and by integrating interactive keys into larger biological Web sites.

Alpha and beta arthropods diversity from the different environments of Parque Nacional Los Cardones, Salta, Argentina. The essential role of the National Parks is to protect nature, in order to prevent the deterioration and loss of the ecosystem under protection. Very few records about the diversity of arthropods are known from Los Cardones National Park, where three eco-regions are protected: Puna and Monte eco-regions and the High Andean Grassland of the Yungas. Here, we aimed to compare the alpha and beta diversity of arthropods in these eco-regions, and to prove if sites from the same ecoregion, show greater similarity between them in their assemblages, than with sites of the other eco-regions. We also identified arthropod orders with higher species richness, and indicated the families that contribute the most to the registered beta diversity. Three sampling sites were established on each eco-region and the arthropods were sampled using pitfall traps and suction samples. We evaluated the obtained inventory through nonparametric estimators of species richness, and compared diversity among eco-regions through "diversity profiles" and "effective number of species". Beta diversity was assessed by different methods such as the Morisita Index, nonmetric multidimentional scaling analysis, a multiple permutation procedure, and a Similarity Percentage analysis. We recorded 469 spp/morphospecies and recognized three arthropod orders (spiders, dipterans and hymenopterans) that are diverse and abundant in the Park. Besides, the diversity in Los Cardones National Park was found to be high, but it was observed higher in the High Andean Grassland of the Yungas, and lower in the Puna. The inventory obtained was good, reached up to the 81% of the species richness estimated by nonparametric estimators. Each eco-region of the park showed a very particular arthropod community that was tested by a multi-response permutation procedure. The species turnover between eco-regions was high, so that the different environments of the protected area are contributing to the maintenance of the regional diversity of arthropods in the park. The assemblages of arthropods belonging to the same eco-region sites showed greater similarity among themselves than with those of more distant sites. This represents the first attempt for biodiversity studies in these areas, but more evaluations are required to detail on the possible climate change and human impacts in the ecosystem.

Both top-down and bottom-up processes are common in terrestrial ecosystems, but how these opposing forces interact and vary over time is poorly understood. We tested the variation of these processes over seasonal time in a natural temperate zone grassland, a field site characterized by strong seasonal changes in abiotic and biotic conditions. Separate factorial experiments manipulating nutrients and cursorial spiders were performed in the wet and dry seasons. We also performed a water-addition experiment during the summer (dry season) to determine the degree of water limitation during this time. In the spring, nutrient addition increased plant growth and carnivore abundance, indicating a bottom-up control process. Among herbivores, sap-feeders were significantly enhanced while grazers significantly declined resulting in no net change in herbivore abundance. In the summer, water limitation was predominant increasing plants and all herbivores while nutrient (N) effects were non-significant. Top-down processes were present only in the spring season and only impacted the guild of grazing herbivores. These results show that bottom-up limitation is present throughout the season in this grassland, although the specific limiting resource changes as the season progresses. Bottom-up processes affected all trophic levels and many different guilds, while top-down effects were limited to a select group of herbivores and did not extend to the plant trophic level. Our results show that the relative strengths of top-down and bottom-up processes can shift over relatively short periods of time in habitats with a strong seasonal component.

Assessing Creepy Crawlies Arthropods are the most diverse group of terrestrial animal species, yet estimates of the total number of arthropod species have varied widely, especially for tropical forests. Basset et al. (p. 1481 , see the cover) now provide more reliable estimates of total arthropod species richness in a tropical rainforest in Panama. Intensive sampling of a half hectare of forest yielded just over 6000 arthropod species. Scaling up this result to the whole forest suggests that the total species diversity lies between 17,000 and 40,000 species.

Islands have traditionally been considered to be any relatively small body of land completely surrounded by water. However, their primary biological characteristic, an extended period of isolation from a source of colonists, is common also to many situations on continents. Accordingly, theories and predictions developed for true islands have been applied to a huge array of systems, from rock pools, to single tree species in forests, to oceanic islands. Here, we examine the literature on islands in the broadest sense (i.e., whether surrounded by water or any other uninhabitable matrix) as it pertains to terrestrial arthropods. We categorize islands according to the features they share. The primary distinction between different island systems is "darwinian" islands (formed de novo) and "fragment" islands. In the former, the islands have never been in contact with the source of colonists and have abundant "empty" ecological niche space. On these islands, species numbers will initially increase through immigration, the rate depending on the degree of isolation. If isolation persists, over time species formation will result in "neo-endemics." When isolation is extreme, the ecological space will gradually be filled through speciation (rather than immigration) and adaptive radiation of neo-endemics. Fragment islands are fundamentally different. In these islands, the ecological space will initially be filled as a consequence of connection to the source of colonists prior to insularization. Species numbers will decrease following fragmentation through the process of relaxation. If these islands become more isolated, species will eventually arise through relictualization with the formation of "paleo-endemics." Given sufficient time, this process can result in generic level endemism on ancient fragment islands, a phenomenon well illustrated in Madagascar and New Zealand. Recognizing the distinction between the different kinds of islands is fundamental for understanding emerging patterns on each, in particular speciation, biodiversity (e.g., neo-endemics versus paleo-endemics), and conservation (e.g., naiveté in interactions with alien species).

Currently, the use of synthetic chemicals to control insects and arthropods raises several concerns related to environment and human health. An alternative is to use natural products that possess good efficacy and are environmentally friendly. Among those chemicals, essential oils from plants belonging to several species have been extensively tested to assess their repellent properties as a valuable natural resource. The essential oils whose repellent activities have been demonstrated, as well as the importance of the synergistic effects among their components are the main focus of this review. Essential oils are volatile mixtures of hydrocarbons with a diversity of functional groups, and their repellent activity has been linked to the presence of monoterpenes and sesquiterpenes. However, in some cases, these chemicals can work synergistically, improving their effectiveness. In addition, the use of other natural products in the mixture, such as vanillin, could increase the protection time, potentiating the repellent effect of some essential oils. Among the plant families with promising essential oils used as repellents, Cymbopogon spp., Ocimum spp. and Eucalyptus spp. are the most cited. Individual compounds present in these mixtures with high repellent activity include a-pinene, limonene, citronellol, citronellal, camphor and thymol. Finally, although from an economical point of view synthetic chemicals are still more frequently used as repellents than essential oils, these natural products have the potential to provide efficient, and safer repellents for humans and the environment.

This study aimed to assess the soil quality of Malubog, Cebu City with nematodes and arthropods as bioindicators in terms of presence and adaptations of these species to the soil. Bioindicators, such as taxa or functional groups, are widely used as signs of environmental change, specific ecological factors or taxonomic diversity to identify the taxa that is sensitive or tolerant to soil stressors. This study was able to determine the soil quality and the effects of urbanization on the soil quality in Malubog, Cebu City. Five samples were collected from four quadrants from Barangay Malubog, Cebu City. Soil sampling was done on 20 November 2016. A 50 meter transect was intersectionally laid on the ground. The invertebrates found on the soil samples were classified accordingly and tallied based on the number of occurrence. The Soil Fauna Index was used to determine the class and species of the following invertebrates. The study proved that terrestrial arthropods and bacteria-feeding nematodes are good biological soil indicators in determining soil quality of agricultural lands. Diversity abundance of terrestrial arthropods such as those organisms under the class Hymenoptera showed a large individual population in the area, which indicates that the soil in Malubog, Cebu City is fertile and most suitable for agricultural purposes.  However, even if the population of bacteria-feeding nematodes is lower compared to the population of terrestrial arthropods obtained in the area, they play a crucial role in soil health management and quality due to their ability to proliferate soil nutrients.

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 halogenated salicylanilides are a large group of compounds developed mainly for their antiparasitic activity in animals. Several halogenated salicylanilides with potent antiparasitic activity have been synthesised of which only closantel, niclosamide, oxyclozanide, rafoxanide and resorantel are commercially available. Closantel and rafoxanide, which represent the most important drugs in the group, are used extensively for the control of Haemonchus spp. and Fasciola spp. infestations in sheep and cattle and Oestrus ovis in sheep in many parts of the world. Niclosamide is used extensively for its anticestodal activity in a wide range of animals. Antiparasitic activity of the halogenated salicylanilides has also been demonstrated against a large number of other internal parasites, in particular haematophagous helminths, and external parasites including ticks and mites, in a variety of animal species. Several cases of toxicity and mortality have been reported for closantel and rafox...

Inventory of free-living freswater arthropods, with synonymical bibliography, occurring in the Pakistani fresh waters is drawn up, almost entirely from taxonomical literature checked until now. Six hundred and thirty two taxa have been recorded since 1892, of these 239 species and sub-species are of Crustacea, 368 species and sub-species are of Insecta, 25 species and sub-species are of Arachnida as well as few unidentified species. The present inventory is composed of the collated records from the publications of the library and internet. Totally 266 selected publications are arranged as resource references.

A well-corroborated morphological scheme of interrelationships for centipedes, once broadly accepted, has been in conflict with molecular data with respect to deep branching events. Expanded taxonomic coverage compared to previous analyses adds longer fragments for 28S rRNA and a structural alignment as part of a sample of four genes (two nuclear ribosomal and two mitochondrial) for 111 extant species; these sequence data are combined with morphology under parsimony and maximum likelihood, exploring both traditional multiple sequence alignment and direct optimization approaches. Novel automated procedures to incorporate secondary structure information are also explored. The molecular data in combination yield trees that are highly congruent with morphology as regards the monophyly of all centipede orders as well as the major groups within each of the large orders. Regardless of the optimality criterion or alignment strategy, the Tasmanian/New Zealand Craterostigmomorpha is resolved in a different position by the molecular data than by morphology. Addition of morphology overturns the placement of Craterostigmomorpha in favour of the traditional morphological resolution and eliminates the need to posit major character reversals with respect to developmental mode and maternal care. Calibration of the tree with Palaeozoic and Mesozoic fossils for a relaxed clock analysis corroborates the palaeontological signal that divergences between centipede orders date to the Silurian and earliest Devonian, and familial divergences are likewise almost wholly Palaeozoic.

In contrast to other terrestrial arthropods, where gaseous O 2 that fuels aerobic metabolism diffuses to the tissues in tracheal tubes, and most other metazoans, where O 2 is transported to tissues by circulating respiratory proteins, the myriapods (millipedes and centipedes) strikingly have tracheal systems as well as circulating hemocyanin (Hc). In order to elucidate the evolutionary origin and biological significance of millipede Hc, we report the molecular structure (subunit composition and amino acid sequence) of multimeric (36-mer) Hc from the forest floor-dwelling giant African millipede Archispirostreptus gigas and its allosteric oxygen-binding properties under various physico-chemical conditions. Archispirostreptus gigas Hc consists of only a single subunit type with differential glycosylation. Phylogenic analysis revealed that millipede Hc is a sister group to centipede HcA, which supports an early divergence of distinct Hc subunits in myriapods and an ancient origin of multimeric Hcs.

Monophyly of Arthropoda is emphatically supported from both morphological and molecular perspectives. Recent work finds Onychophora rather than Tardigrada to be the closest relatives of arthropods. The status of tardigrades as panarthropods (rather than cycloneuralians) is contentious from the perspective of phylogenomic data. A grade of Cambrian taxa in the arthropod stem group includes gilled lobopodians, dinocaridids (e.g., anomalocaridids), fuxianhuiids and canadaspidids that inform on character acquisition between Onychophora and the arthropod crown group. A sister group relationship between Crustacea (itself likely paraphyletic) and Hexapoda is retrieved by diverse kinds of molecular data and is well supported by neuroanatomy. This clade, Tetraconata, can be dated to the early Cambrian by crown group-type mandibles. The rival Atelocerata hypothesis (Myriapoda þ Hexapoda) has no molecular support. The basal node in the arthropod crown group is embroiled in a controversy over whether myriapods unite with chelicerates (Paradoxopoda or Myriochelata) or with crustaceans and hexapods (Mandibulata). Both groups find some molecular and morphological support, though Mandibulata is presently the stronger morphological hypothesis. Either hypothesis forces an unsampled ghost lineage for Myriapoda from the Cambrian to the mid Silurian.

Soil health is presented as an integrative property that reflects the capacity of soil to respond to agricultural intervention, so that it continues to support both the agricultural production and the provision of other ecosystem services. The major challenge within sustainable soil management is to conserve ecosystem service delivery while optimizing agricultural yields. It is proposed that soil health is dependent on the maintenance of four major functions: carbon transformations; nutrient cycles; soil structure maintenance; and the regulation of pests and diseases. Each of these functions is manifested as an aggregate of a variety of biological processes provided by a diversity of interacting soil organisms under the influence of the abiotic soil environment. Analysis of current models of the soil community under the impact of agricultural interventions (particularly those entailing substitution of biological processes with fossil fuel-derived energy or inputs) confirms the highly integrative pattern of interactions within each of these functions and leads to the conclusion that measurement of individual groups of organisms, processes or soil properties does not suffice to indicate the state of the soil health. A further conclusion is that quantifying the flow of energy and carbon between functions is an essential but non-trivial task for the assessment and management of soil health.

The enigmatic arthropod Skania fragilis, from the middle Cambrian (Series 3, Stage 5) Burgess Shale Formation (Yoho National Park, British Columbia, Canada), is redescribed based on 14 new specimens reposited at the Royal Ontario Museum. These specimens provide a clearer picture of the morphology of this taxon and help to resolve conflicting opinions regarding potential homology of particular features. Specifically, the anchor-shaped anterior, which has been compared to a similar structure in the putative Precambrian arthropod Parvancorina, is shown to represent an anterior cephalic doublure with features comparable to the mediolateral spines of marrellids, such as Marrella. Beyond a vaguely cordiform outline, no other features are shown to be shared between Skania and Parvancorina, weakening claims that crown-group arthropods were present in the Neoproterozoic. The removal of these taxa from Arthropoda is in keeping with recent molecular clock analyses, which demonstrate a Cambrian diversification of Euarthropoda. A phylogenetic analysis resolved Skania as the most basal member of Acercostraca, a clade of marrellomorphs including Vachonisia and Xylokorys, united by the presence of a cordiform dorsal shield. Similarities between these taxa and marrellids may indicate that the elongate posterior spines of Marrella and related taxa, and the dorsal shield of acercostracans have a common origin akin to the carapace anlagen of extant crustaceans. • Key words: marrellomorph, carapace formation, Burgess Shale. LEGG, D.A. 2015. The morphology and affinities of Skania fragilis (Arthropoda) from the middle Cambrian Burgess Shale.

Traditionally, measurement of the acute toxicity of pesticides to beneficial arthropods has relied largely on the determination of an acute median lethal dose or concentration. However, the estimated lethal dose during acute toxicity tests may only be a partial measure of the deleterious effects. In addition to direct mortality induced by pesticides, their sublethal effects on arthropod physiology and behavior must be considered for a complete analysis of their impact. An increasing number of studies and methods related to the identification and characterization of these effects have been published in the past 15 years. Review of sublethal effects reported in published literature, taking into account recent data, has revealed new insights into the sublethal effects of pesticides including effects on learning performance, behavior, and neurophysiology. We characterize the different types of sublethal effects on beneficial arthropods, focusing mainly on honey bees and natural enemies,...

Arthropods
ISSN 2224-4255
http://www.iaees.org/publications/journals/arthropods/articles/2019-8(4)/2019-8(4).asp

Volume 8, Number 4, 1 December 2019

Cover Pages
[Front Pages (94K)] [Back Pages (55K)]

Articles

Walking leg regeneration observed in three families and four species of antarctic sea spiders
Arthropods, 2019, 8(4): 110-117
John A. Fornshell
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First record of the crab, Droippe quadridens (Fabricius, 1793) (Brachyura: Dorippidae), from the Iraqi coastal waters of the NW Arabian Gulf, with notes on the occurrence of seven species of crabs in the region
Arthropods, 2019, 8(4): 118-126
KhaledKh Al-Khafaji, Tariq H.Y. Al-Maliky, Anwar M.J. Al-Maliky
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Xylophagous millipede surface area to volume ratios are size dependent in forests
Arthropods, 2019, 8(4): 127-136
Mark Cooper
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Size dimorphism in six juliform millipedes
Arthropods, 2019, 8(4): 137-142
Mark Cooper
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Inventory of freshwater arthropods in Pakistan
Arthropods, 2019, 8(4): 143-175
Quddusi B. Kazmi, Farhana S. Ghory
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The central bearded dragon (Pogona vitticeps) is one of the most popular pet lizards. However, little is known regarding their nutrient requirement, or their natural diet. Therefore, the stomach contents of 14 free-roaming P. vitticeps were determined by flushing. These stomach contents were described taxonomically, and analyzed for crude protein content as well as fatty acid content and composition. Most of the dry matter intake was in the form of animal material (61%) stemming from nine arthropod orders. The most abundant were alates of the termite Drepanotermes sp., accounting for 95% of the total number of prey items and more than half of the total dry matter (DM) intake. Plant material contributed 16% of the total DM intake. The diets were high in crude protein (41-50% DM) and the total fatty acid content was 14-27% of the DM intake. The main fatty acid was C18:1n9c (51-56% of total fatty acids), and polyunsaturated fatty acids (n3 and n6) comprised 6-8% of the total fat intake. Our data suggest that P. vitticeps is an opportunistic predator, which exploits the seasonal availability of prey. Based on our data and other studies, a diet consisting of several insect species, supplemented with leafy vegetables, rich in n3 FA's, would best resemble the expected natural diet of P. vitticeps. Zoo Biol. XX:XX-XX, 2015.