Charles Francis Massy Swynnerton

Charles Francis Massy Swynnerton CMG (3 December 1877 – 8 June 1938) was an English naturalist noted for his contributions to tsetse fly research.

His father was a senior chaplain in the Indian Army, and his mother the daughter of Major W. H. Massy, of Grantstown Hall, County Tipperary.

In Natal he met the renowned entomologist and authority on Curculionidae, Guy Anstruther Knox Marshall (1871–1959), who owned some farms in Southern Rhodesia and persuaded Swynnerton to manage one of these in the Melsetter district.

The British Museum was a regular recipient of his plant and insect specimens which were lauded for displaying "a precision in localisation and notes on economic uses which made this collection a model one".

During this period Guy Marshall became chief editor of the Bulletin of Entomological Research and remained a close friend and mentor to Swynnerton.