Frederick Arthur Godfrey Muir (24 April 1873 – 13 May 1931) was an English entomologist who worked in Africa and Hawaii.
He studied in private schools and worked for ten years in Africa with the Eastern Telegraph Company from 1886 to 1905.
Work included travel to Southeast Asia to seek parasites to control the pests of cane in Hawaii.
In 1913 he visited Japan to seek parasites for the root grub Anomala orientalis which was causing great damage to sugar cane.
Muir conducted pioneering experiments on biological control, mass-rearing along with J.C. Kershaw, and introducing, the tachinid fly Ceromasia sphenophori into Hawaii.