SUMMARYSignificant correlations between 25 quantitative characters of worker honey bees used for the morphometric identification of Africanized honey bees (Apis mellifera), seven measures of colony defence and 12 for alarm pheromone production were calculated from data on colonies in Louisiana, USA, and Monagas, Venezuela, two years after the arrival of Africanized honey bees in the eastern portion of Venezuela. The bees in the Venezuela group were identified as European (70%), European with evidence of introgression of Africanized genes (5%), Africanized with evidence of introgression of European genes (7%) and Africanized (18%), indicative of a population undergoing hybridization. For the Venezuelan population alone, the correlations between defensive behaviour and morphometric identification as Africanized were not significant. Therefore, defensive behaviour alone is not an adequate indicator for identification or certification programmes in areas undergoing Africanization.