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The wolf spider Lycosa terrestris (Araneae: Lycosidae) is a well known arthropod containing toxic compounds. It has significant predatory potential in addition to its uses in medicinal and insecticidal formulation. Current investigations were aimed to extract and partially characterize the venom of L. terrestris and the susceptibility tests to evaluate antibacterial potential of venom supernatant and venom pellets against four pathogenic bacterial strains i.e., Gram negative Acinetobacter sp. and Pasteurella sp. and Gram Positive Staphylococcus sp. and Streptococcus sp. Results of this study revealed that the venom of L. terrestris contained six relatively high molecular weight peptides ranging from 125 kDa to 35 kDa. Moreover, results of the susceptibility test confirmed the bacteriostatic action of venom supernatant against aerobic Gram negative Acinetobacter sp. in dose dependent manner. A reduced trend of bacteriostatic inhibition was also observed for venom pellets against Acinetobacter sp. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM PUBLISHER]

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]

The article presents a study that investigated the possible factors responsible for the coexistence of three hunting spiders and two orb web spiders in a rice ecosystem of central Punjab, Pakistan. The authors of the study selected two plots, 400 square meters each, in a monoculture area of Sheikupura District in Punjab. Pitfall trap and a suction device were used to record the density of spiders during the study. The authors also discovered different active density of all spider species among different trapping sessions. They also found different reproductive period, abundances of young and adults, and prey size.

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]