DIVERSITY AND SEASONAL ABUNDANCE OF PREDATORY SPIDER FAUNA IN PADDY ECOSYSTEM

Abstract

A field experiment was conducted during kharif 2019 to study the dynamics and diversity of spiders in paddy ecosystem at Rajendranagar, Telangana. A total of 22 spider species were documented belonging to 11 families and 20 genera. Out of 22 species 6 species were dominant viz., Pardosa pseudoannulata, Chrysso sp., Tetragnatha mandibulata, T. elongata, Lycosa
pseudoannulata, Leucage sp.; 15 species were sub-dominant viz., Runcinia grammica, Heteropoda venatoria, Arctosa maculata, Araneus inustus, Argiope anasuja, Zygiella notata, Z. indica, Chieranthium sp., Agelenopsis sp., Atypena formosana, Hamataliwa sp., Oxyopes salticus, Bianor aurocinctus, Evarcha falcata, Mymarachne sp. and one species was satellite i.e., Neoscona theisi. Among all species P. pseudoannulata was most dominant and N. theisi was scarce. Of all families recorded, Tetragnathidae was predominant, while Linyphiidae was least representative of total spider population in experimental plot. Density, Shannon-Weiner index (H’), Simpson’s diversity index (ë), Margalef richness index (D) and Pielou’s evenness index (J) ranged from 0.30 to 7.90 sq. m, 1.10 to 2.84, 0.83 to 1.00, 1.82 to 6.79 and 0.35 to 0.91, respectively, indicating that spider fauna in paddy ecosystem were moderately diverse and evenly distributed. The highest diversity was recorded during reproductive stage of crop i.e., 36 to 40 Standard meteorological weeks (SMW) during high pest density, suggesting paddy ecosystem of Rajendranagar could be pronounced to be a stable ecosystem with moderate diversity of spiders.