Cynthia Evelyn Longfield (16 August 1896 – 27 June 1991) was an Anglo-Irish entomologist and explorer and the first woman member of the Entomological Society. She was an expert on the dragonfly and an explorer. She was called "Madame Dragonfly" for her extensive work. She was passionately fond of dragonflies and her dominant area of interest was natural history. She travelled extensively and published The Dragonflies of the British Isles in 1937. She worked as a research associate at the Natural History Museum, London. Longfield was the expert on the dragonflies at the museum, researching particularly African species. Early life Cynthia Evelyn Longfield was born on 16 August 1896, on Pont Street, Belgravia, London. She was the youngest daughter of Montifort and Alice Longfield, of Castle Mary, Cloyne, County Cork. She had two sisters. Alice Longfield grew up near Oxford, and was the daughter of a scientist. Alice died in 1945. The family home at Castle Mary was burned down in 1920 by rebels, and Park House was rebuilt on the grounds. Career Longfield joined the Army Service Corps during the First World War, later moving to an aircraft factory on Fullham Road. She visited South America between December 1921 and March 1922. She travelled to the Andes and Lake Titicaca. In 1923 she travelled to Egypt, where she caught a scorpion at the tomb of Ramases IX. In the same year answered an advertisement to join Evelyn Cheesman of London Zoo on a research trip to the Pacific, specifically the Galapagos Islands. They sailed aboard the St George, which left Dartmouth on 9 April 1924. She collected coleoptera and lepidoptera as an assistant to an entomologist, Cyril Collenette. The pair used machetes to hack through the undergrowth of the Amazon jungle to collect specimens for the Natural History Museum of London. She joined the Entomological Society of London in 1925, and later the same year joined the Royal Geographical Society. She was the first woman member of the Entomological Society. In 1926 she joined the London Natural History Society. She was elected president of the society for 1932 and 1933. On 28 March 1938 she joined the Auxiliary Fire Service, and ensured that a turntable ladder was used upon the bombing of the department in April 1941, during WWII. Cyril Collenette stated that her actions in relation to this likely saved the Museum from destruction. Longfield was a voluntary