Charles Tate Regan (February 1878 - 13 January 1943) was a British ichthyologist, working mainly around the beginning of the 20th century. He did extensive work on fish classification schemes.

Born in Sherborne, Dorset, he graduated from Cambridge University and in 1901 joined the British Museum (Natural History), where he came to be in charge of the zoology program, and later director of the entire museum, in which role he served from 1927 to 1938.

Among the species he described are the Siamese Fighting Fish Betta splendens.

In turn, a number of fish species have been named regani in his honor:

• Anadoras regani
• Apistogramma regani
• Apogon regani
• Astroblepus regani
• Callionymus regani
• Cetostoma regani
• Crenicichla regani
• Diaphus regani
• Engyprosopon regani
• Gambusia regani
• Hemipsilichthys regani
• Holohalaelurus regani
• Hoplichthys regani
• Hypostomus regani
• Julidochromis regani
• Lycozoarces regani
• Neosalanx regani
• Symphurus regani
• Trichomycterus regani
• Tylochromis regani
• Vieja regani
• Zebrias regani

Bibliography

• Regan, C. T. (1908). "A revision of the British and Irish fishes of the genus Coregonus." Annals and Magazine of Natural History 2, 482-490.
• Regan, C. T. (1911). The Freshwater Fishes of the British Isles. Methuen & Co. Ltd.: London.