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Present study was carried out to investigate the variation in web architecture of Larinia chloris (Audouin 1826) in relation to seasonal differences and the biotic factors of the environment. In addition, relative abundance, behavior, and predatory potential of L. chloris were also recorded. For this purpose, 100 orb-webs of L. chloris were observed in rice fields (August-October, 2022) from 3 districts of Punjab (Lahore, Sheikhupura, and Kasur). Percent abundance of L. chloriswas found to be highest in rice fields from Barki road, Lahore (39.53%). All the webs of L. chloris were vertical at height equal to the height of vegetation (115.2 ± 9.7 cm). Time required to complete the web was 45 ± 5 min. There was positive correlation between web architecture and vegetation height. Web capture area and average mesh height of L. chloris also showed positive correlation with carapace length. There was a significant difference in various web parameters (number of spirals, number of radii, capture area, average mesh height, upper radii, lower radii, left radii, and right radii) among different trapping months. A total of 1,326 insects were recorded from the 100 webs of L. chloris. The prey abundance was found to be highest in the fields from Barki Road, Lahore. The majority of the prey collected from webs of L. chloris belonged to order Diptera, Hemiptera, Coleoptera, and Lepidoptera. However, prey items recorded during different growth stages (from vegetative to ripening) varied significantly. This is the first ever report describing the ecology of L. chloris in rice fields from Punjab, Pakistan., (© The Author(s) 2023. Published by Oxford University Press on behalf of Entomological Society of America.)

Morphological study of 1,795 spiders from sites across Pakistan placed these specimens in 27 families and 202 putative species. COI sequences >400 bp recovered from 1,782 specimens were analyzed using neighbor-joining trees, Bayesian inference, barcode gap, and Barcode Index Numbers (BINs). Specimens of 109 morphological species were assigned to 123 BINs with ten species showing BIN splits, while 93 interim species included representatives of 98 BINs. Maximum conspecific divergences ranged from 0-5.3% while congeneric distances varied from 2.8-23.2%. Excepting one species pair (Oxyopes azhari-Oxyopes oryzae), the maximum intraspecific distance was always less than the nearest-neighbor (NN) distance. Intraspecific divergence values were not significantly correlated with geographic distance. Most (75%) BINs detected in this study were new to science, while those shared with other nations mainly derived from India. The discovery of many new, potentially endemic species and the low level of BIN overlap with other nations highlight the importance of constructing regional DNA barcode reference libraries., Competing Interests: The authors have declared that no competing interests exist.

The present study was designed to record the effect of λ-cyhalothrin, Bifenthrin, and Glyphosate on the mortality, avoidance behavior, foraging activity, and activity of Acetylcholine esterase (AChE) and Carboxylesterase (CarE) in Neoscona theisi (Walckenaer, 1841). Highest mortality (70%) in N. theisi was recorded against λ-cyhalothrin. However, Glyphosate was found to be least toxic. Spider spent less time on insecticides/herbicide-treated surfaces. Insecticides/herbicide-treated N. theisi consumed less prey than untreated control spiders. Similarly, when N. theisi were offered insecticide/herbicide-treated prey, they consumed significantly less. Increased AChE and CarE activities were recorded in insecticides/herbicide-treated spiders as compared to control group. Total protein contents were less in insecticides/herbicide-treated spiders than control group. The results revealed that λ-cyhalothrin is more harmful to spiders as compared to Bifenthrin and Glyphosate. It is suggested that the effect of all pesticides used in agro-ecosystem on beneficial insects should be evaluated before using them in the fields., (© The Author(s) 2019. Published by Oxford University Press on behalf of Entomological Society of America.)

In recent years, DNA barcoding has become quite popular for molecular identification of species because it is simple, quick and an affordable method. Present study was conducted to identify spiders of most abundant families, i.e. Salticidae and Lycosidae from citrus orchards in Sargodha district using DNA barcoding. A total of 160 specimens were subjected to DNA barcoding but, sequences up to 600 bp were recovered for 156 specimens. This molecular approach proved helpful to assign the exact taxon to those specimens which were misidentified through morphological characters in the study. We were succeeded to discriminate six species of Lycosidae and nine species of Salticidae through DNA barcoding. Results revealed the presence of clear barcode gap (discontinuity in intra- and inter-specific divergences) for members of both families. Furthermore, the maximum intra-specific divergence was less than NN (nearest neighbour) distance for all species. This suggested the reliability of DNA barcoding for spider's identification up to species level. We got 98% success in our study. It is concluded from present study that DNA barcoding is more reliable tool especially for immature spiders, when morphological characters are ambiguous.

Elevated levels of insecticides detoxifying enzymes, such as esterases, glutathione S-transferases (GSTs), and cytochrome P-450 monooxygenases, act in the resistance mechanisms in insects. In the present study, levels of these enzymes in the insecticide-resistant ground spider Pardosa sumatrana (Thorell, 1890) were compared with a susceptible population (control) of the same species. Standard protocols were used for biochemical estimation of enzymes. The results showed significantly higher levels of nonspecific esterases and monooxygenases in resistant spiders compared to controls. The activity of GSTs was lower in the resistant spiders. Elevated levels of nonspecific esterases and monooxygenases suggest their role in metabolic resistance in P. sumatrana. The reduced levels of total protein contents revealed its possible consumption to meet energy demands., (© 2016 Wiley Periodicals, Inc.)

Spiders are natural predators of many insect pests and preferred as they are carnivores. In the present study we identified the cursorial spiders of different families using DNA barcoding as it is very helpful in identifying species where morphological identifications can be difficult e.g., delimitation of juvenile stages. Standard barcode region of CO1 gene of 64 samples was amplified. The sequences of 658 base pairs were recovered from 62 samples, representing 7 families, 20 genera and 27 species. Araneidae was the most dominant family followed by Salticidae, Oxyopidae, Clubionidae, Tetragnathida, Thomisidae, Mitergidae and Lycosidae. The interspecific value of divergence was more than the intraspecific value of divergence for all seven families which described a clear barcode gap. No overlap was recorded in intraspecific and interspecific divergence value. Furthermore, distance to NN was higher than the maximum intraspecific value for all species. A barcode reference library of the cursorial spiders of Punjab University, Lahore and Soon Sakeser Valley Punjab was also established. It is concluded that CO1 has potentially enough information for fast and accurate identification of spiders. Although, morphological studies alone are working satisfactory for the identification of spiders, still its efficiency increased when combined with DNA barcoding. [ABSTRACT FROM AUTHOR]

In the present study, DNA barcoding was used to assess the percentage accuracy of morphological base identification of spiders from the agriculture fields of district Layyah, Punjab, Pakistan. A total of 872 spiders were captured from June to August of 2017. All the collected spiders were brought to molecular laboratory at GC University Lahore, preserved in 95% ethanol and stored at −20 °C until the DNA extraction. Spiders were evaluated morphologically on the basis of different identification Keys and Catalogs. Morphological identification revealed the presence of 12 families, 29 genra and 49 species. To evaluate the authenticity of morphological identification, tissue samples of 96 specimens were sent to Canadian Center for Biodiversity and Genomics, University of Guelph, Canada. A 658-base pair sequence of COI (Cytochrome c Oxidase Subunit I) of 90 specimens was retrieved successfully, which confirmed the presence of 11 families, 25 genra and 47 species. On the basis of molecular results, all the misidentified specimens were then allotted the correct taxon. Overall accuracy of morphological based identification was 88%. It is concluded from the present study that morphological investigations to identify a spider, are satisfactory but to enhance the accuracy, pace and credibility of results, molecular technique like DNA barcoding is considerable. Furthermore, to magnify authenticity of evaluation of spiders, integrated barcoding- combination of molecular methods and conventional taxonomy- is compulsory. [ABSTRACT FROM AUTHOR]

Spiders are important insect predators and being used as model organisms in various investigatory studies however, work on this group is difficult due to the constrains in their species level identification. DNA-barcoding is a promising approach to minimize the difficulties of taxonomists to delimit species. Current study was designed to provide first barcode record of some common spiders from Punjab, Pakistan. The standard barcode region (658 base pairs of Cytochrome C oxidase subunit I), in multiple specimens of all species, was sequenced. DNA based data corresponded the morphological study, confirming the presence of five species i.e., Clubiona analis Thorell, 1895, Cyrtophora citricola (Forskål, 1775), Leucauge decorata (Blackwall, 1864), Neoscona theisi (Walckenaer, 1841) and Oxyopes javanus Thorell, 1887. There was clear gap in intraspecific and interspecific values of genetic distances. For every species, the maximum interaspecific divergence was less than the minimum distance to its nearest-neighbour. The divergence values within and between species ranged from 0-1.6% and 17.6-23.7%, respectively. Five species were also clearly separated based on parsimony analysis. It is concluded that DNA barcoding is a reliable tool to delimit studied spider species. [ABSTRACT FROM AUTHOR]

Citrus leaf miner, citrus whitefly and citrus psylla are the major insect pests of citrus orchards in district Sargodha, Pakistan. Spiders, being natural predators are helpful to keep the insect pest populations below economic enjoy level. The diversity and guild structure of spiders in the citrus orchards was recorded in the study. Seasonal dynamics of spiders and insect pests and predator-pest (spider-pest) relationships were also studied. In total, 2665 spiders belonging to 12 families, 23 genera and 43 species were captured. Species and family composition of spiders varied on the foliage and ground. Abundance of spiders among sites differed significantly. However, nonsignificant difference was observed in the richness, diversity and evenness among sites. Abundance and infestation of pest was found to synchronize with the abundance of spiders. Maximum infestation of citrus leaf miner, citrus whitefly and citrus psylla was recorded in March, 2014 supporting maximum spider abundance in this month. There was strong positive correlation between abundance of insect pests and predators (spiders) which suggested that spiders could effectively control insect pest populations in the field. [ABSTRACT FROM AUTHOR]

The venom of two dominant species of wolf spiders, Pardosa sumatrana Thorell and Pardosa birmanica Simon, was extracted and characterized. Insecticidal potential of crude venom and selected peptide fractions (i.e. 35-kDa fraction of both spiders) was evaluated in the laboratory using Rhopalosiphum padi (Linnaeus) (Homoptera: Aphididae) as a model pest. Results of the study showed that both the crude venom and the protein fractions caused significantly higher mortality in treated aphids compared to the control. It is concluded that both the crude venom and the protein fractions possess insecticidal potential. [ABSTRACT FROM AUTHOR]

Present study was designed to evaluate the toxicity of Confidor and Buctril-M on two dominant spiders of wheat ecosystem of Punjab, Pakistan i.e., Lycosa terrestris Butt, Anwar & Tahir, 2006 and Oxyopes javanus Thorell, 1887. Residual toxicity of pesticides on these spiders in the laboratory and in the fields was also studied. Buctril-M was found less toxic compared to Confidor for both species. Mortality of both spider species declined with the increase of post sprayed time for both pesticides. Altogether we captured 2260 individuals of L. terrestris (707 from treated field and 1553 from control field) -. Similarly, in total of 637 individuals of Oxyopes javanus were collected (212 from treated and 425 from control) from the studied plots. It is concluded that toxicity of Confidor is higher than Buctril-M. Moverover, Confodor remains active for longer time in the field compared to Buctril-M. [ABSTRACT FROM AUTHOR]

The article discusses a study which investigated the effects of tillage activity on the abundance of ground spiders in rice ecosystem in Pakistan. Spiders are known for consuming a wide range of prey species and for preventing economically importance outbreaks. Findings showed no difference in the number of species captured from the tilled and untilled fields. However, lower number of spiders was observed in the tilled field compared to the untilled field. The study indicates that tilled fields support less spiders, which reduces the impact of spiders' biological control in the fields.

The article presents a study on the importance of spiders in the citrus orchards in Lahore, Pakistan. The researchers performed the study at the citrus field of the University of the Punjab, wherein they used pitfall traps to collect the spiders. They brought the spiders gathered in every trapping session to the laboratory, where they were washed with alcohol and stored in a mixture of 20 percent glycerol and 80 percent alcohol. They found the presence of a rich spider fauna at the citrus field of the study area, which can effectively suppress the pest populations.

Present study was designed to assess the prey preference behaviour of three most dominant hunting spiders [ Lycosa terrestris Butt, Anwar and Tahir 2006 (Araneae: Lycosidae), Pardosa birmanica Siman 1884 (Araneae: Lycosidae) and Oxyopes javanus (Thorell 1887) (Araneae: Oxyopidae)] of rice ecosystems both in the laboratory and in the field. Two types of laboratory experiments, i.e., choice and no choice feeding, were performed using only adult male and female specimens of the spiders. No choice test showed that each of the three hunting spiders readily consumed larvae and nymphs of rice pests offered. Female hunting spiders consumed more prey compared to male hunting spiders. Results of choice feeding test indicated that L. terrestris and P. birmanica preferred nymphs of rice insect pests while O. javanus preferred larvae of rice insect pests. Results of direct observations showed that in August, dipterous insects were the most numerous rice pests consumed by L. terrestris, P. birmanica and O. javanus, comprising over 56.3, 38 and 48% of their respective diets. In contrast, in September, the proportion of dipterous insects decreased dramatically and hoppers become the most numerous pests, comprising over 50, 51 and 41% of all prey and spiders consumed by L. terrestris, P. birmanica and O. javanus, respectively. In October, aquatic Heteroptera were frequently observed in their diets. Predatory potential of these hunting spiders differed statistically in the laboratory as well as in the field. It is concluded from the results of present project that studied species of spiders could successfully be used to control insect pests of rice ecosystems. [ABSTRACT FROM AUTHOR]