Effect of heavy metal, copper sulphate and potassium chromate on behaviour of “Tailless water flea” Simocephalus vetulus (Crustacea - Cladocera)

Abstract

Water fleas constitute major zooplankton population of fresh water aquatic ecosystem. Their population density is an indicative of well-being of aquatic bodies. Simocephalus vetulus (Crustacea -Cladocera) is a tailless water flea and is well suited lab model for environmental monitoring. Copper a Gray listed heavy metals despite being an essential micronutrient, becomes highly toxic when present in excess quantity in aquatic ecosystem thereby causing deleterious effects on aquatic flora as well as fauna. The water-flea exposed to acute 0.37 mg/l (96hr LC 50 ), sub-acute 0.0925 mg/l (25% of 96hr LC 50 ) value and chronic 0.037 mg/l (10% of 96hr LC 50 ) value of copper sulphate and acute 0.16 mg/l (96 hr LC 50 ), sub-acute 0.04 mg/l (25% of 96 hr LC 50 ) value and chronic 0.016 mg/l (10% of 96 hr LC 50 ) value of potassium chromate showed behavioural alterations like initial hyperactivity, fast appendage movements and in phototaxis, geotaxis and avoidance indices. At later stage erratic swimming and spinning, reduced activity, loss of balance, reduced feeding and darkening of cuticular coloration, reduced phototactic, geotaxis and avoidance indices were the major effects on its behaviour. The behavioural alterations of S. vetulus showed the most susceptible and foremost indication of potential toxic effects. Various behavioural parameters, used in present study may serve as better biomarkers about metal toxicity and monitoring of drinking water quality.

A Review and Meta-Analysis of the Studies Conducted on the Impact of Micropollutants on the Aggressive Behaviors of Some Crustaceans

“…Eighteen studies with effect sizes were included in the meta-analysis (Table 1; Fig. 1) [30][31][32][33][34][35][36][37][38][39][40][41][42][43][44][45][46], [19]. The total number of candidate crustaceans or subjects across the studies was 1101.…”

A report on freshwater tailless flea, Simocephalus vetulus from Haridwar, located in foothills of Shivalik Himalaya in Uttarakhand, India

“…Most widely studied genera of family daphniidae, Daphnia and Simocephalus which constitute of major place in the aquatic food chain. Genus Simocephalus commonly called as "tailless water flea" and are dominant species are a littoral community (Green, 2009;Mishra et al, 2016a;and 2016b;Thakur and Kocher, 2017;Mishra et al, 2018). Cladoceran species are widely used as test model toxicological, ecological and physi-ological studies (Freitas and Rocha, 2010;Smirnov, 2014;Sadeq and Beckerman, 2019).…”

“…They mature approximately in a week and can have thousands of offspring. During unfavourable weather conditions, they can produce resting eggs which can withstand time, heat, cold, and drought (Smirnov, 2014and Mishra et al, 2016aand 2018. Therefore, proper identification and studies on S. vetulus are necessary considering the above facts.…”