Biology of Spider, Cheiracanthium Melanostomum (Thorell) Under Laboratory Conditions

Investigation on the biology of spider, Cheiracanthium melanostomun (Thorell) was studied for the first time from sindh for Study on biology of spider, Cheiracanthium melanostomum on natural diets was carried out under lab conditions (27oC + 2oC) from October to July 2011. For this purpose, one gravid female spider was kept in Petridis. After hatching twenty spider ling were kept in separate petridishes, the mean development period of 1st, 2nd, 3rd, 4th, 5th, 6th, 7th, and 8th instars was 12.4+0.33, 20.95 + 0.49, 17.10+ 0.45, 36.50 + 1.94, 17.05 + 0.93, 23.55 + 2.30, 20.40 + 3.44 and 18.10 + 3.40, respectively. Mean survival of male ranged between 211-222 days, whereas, female lived from 209-268 days. The result further showed that repopulation period of spider varied from 30-50 second, copulation period lasted up to 3-4 minutes; the incubation period lasted 14-15 days. The fecundity of each female ranged from 57-65 eggs. The fertility ranged between 46-53 eggs whereas, hatching ranged from 80-81.70%. The result further showed that maximum mortality took place in eggs up to 26.15% followed by 7.89-12.5% in 1st to 4th instars. Afterwards, mortality remained decreased 3.57-3.22% in 5th to 8th instars. The study further showed that male adults emerged in 6th instars whereas, female adults emerged in 8th instars and male female ratio was 6:21. The results obtained shall be useful for the researchers, progressive farmers, extension workers and all the stakeholders in the field of agriculture for suppression of the pest population through use of predatory spiders as biological control agents.