[History of the discovery of Biomphalaria occidentalis Paraense, 1981]

The article addresses the discovery of Biomphalaria occidentalis Paraense, a mollusk whose shell is indistinguishable from that of B. tenagophila, natural vector of Schistosoma mansoni. This reconstruction of the history of its discovery necessarily entails reference to the professional life of malacologist Wladimir Lobato Paraense. In addition to demonstrating how essential basic biology and taxonomy are in the epidemiology of mansoni schistosomiasis, the study also focuses on the discovery process itself and the socioeconomic factors which influenced it.