We redescribe the holotype of Crelloxea spinosa, with emphasis on characters that demonstrate unequivocally that it is a freshwater sponge, Spongilla alba Carter, 1849. We concluded that the uncertainty about the precise location of the collection site ultimately led to this misidentification. We also show how, on the other hand, additional information on the back of the label and the keeping of the fieldbook by the collector for 47 years allowed us to correct this unfortunate mistake.