author

O. A. (Oskar Augustus) Johannsen

1870–1961

Best known as a pioneering American entomologist, he wrote clearly and in depth about flies and other insects, helping shape early 20th-century insect study. His work remains especially associated with Diptera and aquatic insect life.

1 Audiobook

Handbook of Medical Entomology

Handbook of Medical Entomology

by O. A. (Oskar Augustus) Johannsen, William A. (William Albert) Riley

About the author

O. A. Johannsen was Oskar Augustus Johannsen (May 14, 1870 – November 7, 1961), an American entomologist. Reliable sources available here identify him as a specialist in Diptera, the order of insects that includes true flies.

He is closely linked with major reference works on aquatic insects and fly classification, including Aquatic Diptera. The surviving catalog and species-reference records we found suggest a long scholarly career centered on careful description and identification rather than popular writing.

Because the available source material in this session is limited, it is safest to describe him as an important scientific author in entomology whose books served students and researchers of insect taxonomy and natural history.