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The effects of elevated CO2 concentration on the growth and development of the funnel-web weaving spider Agelena labyrinthica (Clerck) (Araneae: Agelenidae) were studied in climate chambers with low (370 μl l−1) or high (750 μl l−1) CO2 concentration. Seventh-instar A. labyrinthica cultured under each of these CO2 concentrations were randomly selected to determine nutrient composition (total protein, total amino acid, and free fatty acid) and digestive or detoxification enzymes activity (peroxidase, amylase, and superoxide dismutase) using test kits. When reared under high CO2 concentration, total development of A. labyrinthica was significantly faster. Carapace length and width and body weight did not differ between CO2 concentrations, nor the levels of protein and total amino acids in seventh-instar A. labyrinthica. However, free fatty acid levels were significantly lower under high CO2 concentration. Specific activities of peroxidase and superoxide dismutase in seventh-instar A. labyrinthica did not differ between CO2 concentrations. The specific activity of amylase under high CO2 concentration was higher than that of the low CO2 group. The effects of elevated CO2 on A. labyrinthica varied from those on the wandering spider Pardosa astrigera L Koch, as found in an earlier study. Apparently, elevated CO2 has a species-specific impact on spiders.

The objective of the present study was to assess the ecotoxicological responses of Pardosa pseudoannulata to a common environmental pollutant, cadmium. Third-instar spiderlings and adult spiders were exposed to sublethal concentrations of CdCl2 solution in their drinking water. The Cd content in P. pseudoannulata adults increased significantly with the number of days of exposure to a 0.2 mM CdCl2 solution, when exposed to 2 mM CdCl2 solution, the Cd content in the spiders increased sharply in the first two (male) or three (female) weeks, and then no significant changes were recorded following with the next three (male) or two (female) weeks exposure. Exposure of spiders to Cd contaminated drinking water resulted in reduced body mass, delayed development, fewer eggs and increased mortality. Significantly higher activities of superoxide dismutase, catalase and glutathione-s-transferase were recorded in the spiders after 7 day exposure to 0.2 mM CdCl2 solution. However, longer-term exposures or increased Cd concentrations did not result in significantly higher antioxidant enzyme activity relative to control treatment.