Dr Anthonie Johannes Theodorus Janse also known as Antonius Johannes Theodorus Janse and by other spelling variations, was a South African entomologist who specalised in Lepidoptera. Janse was born in the Hague, Netherlands in 1877 to Antonie Johannes Janse and his wife Willemina Broekhuisen. He migrated to South Africa in 1889 and taught as a missionary in schools in northern Transvaal Waterval (Nuwe Smitsdorp), was interned at Pinetown during the Second Boer War. He worked as a photographer in Pietersburg. He taught biology, geography, and human physiology at Normal College, Pretoria, in 1905 where stayed until his retirement in 1937. He was also was in charge of the Normal College Herbarium.