Apis mellifera scutellata, classified by Lepeletier, 1836 - (African honey bee) Central and West Africa, now hybrids also in South America, Central America and the southern USA. In an effort to address concerns by Brazilian beekeepers and to increase honey production in Brazil, Warwick Kerr, a Brazilian geneticist, was asked by Brazilian Federal and State authorities in 1956 to import several pure African queens from Tanzania to Piracicaba-São Paulo State in the south of Brazil. In a mishap some queens escaped. The African queens eventually mated with local drones and produced what are now known as Africanized honey bees on the American continent. The intense struggle for survival of honey bees in sub-Saharan Africa is given as the reason that this sub-species is proactive in defending the hive, and also more likely to abandon an existing hive and swarm to a more secure location. They direct more of their energies to defensive behaviors and less of their energies to honey storage. African honey bees are leather colored, difficult to distinguish by eye from darker strains of Italian bees.
If it was just the queen that escaped, how did AHB get established? I assume this is an incomplete accounting of what happened. Correct? If not, maybe I'll just buy myself a bunch of queens and some more woodenware.