Costa, M.G., Barbosa, J.C., & Yamamoto, P.T. 2006 Distribuiçao de probabilidade de ocorrencia de Orthezia praelonga Douglas (Hemiptera: Sternorrhyncha: Ortheziidae) na cultura de citros. [Probability distribution of Orthezia praelonga Douglas (Hemiptera: Sternorrhyncha: Ortheziidae) in citrus.]. Neotropical Entomology 35(3): 395-401.

Notes: The probability distribution of the orthezia scale, O. praelonga, was studied in plots of commercial orange orchards (Citrus sinensis cv. "Pera Rio"), with 5, 9 and 15 years of age, during one year 2004-05 in Sao Paulo, Brazil. The survey of presence or absence of the pest in the plants was carried through twenty samplings in the total area of each plot and visually inspecting each plant. The dispersion indices used were: variance/mean relationship (I), index of Morisita (I SUB delta), coefficient of Green (Cx) and k exponent of negative binomial distribution for each sampling. The negative binomial distribution was more representative of the frequency distribution data of this scale in citrus, since the variance was superior to the average in all samplings. The analysis of the aggregation index showed that the majority of the samplings presented aggregate distribution for the scales.