Spatial distribution pattern of spittlebug nymph, ptyelus nebulus (Fabricius) (Homoptera, Aphrophoridae).

Distribution pattern of spittlebug nymph, Ptyelus nebulus (Fabricius) (Homoptera, Aphrophoridae) was studied in the months of rainfall, June, July and August by using different statistical measures. All the estimators confirm that nymphs of spittlebug were aggregated in distribution. The cause of aggregation was also calculated by using formula of Arbous and Kerrich (1951) and it indicates that clumping of nymphs was due to environmental factors.