The Yucatan flagfish (Garmanella pulchra), also known as the snakeskin killifish, is a species of pupfish from the family Cyprinodontidae.

It is found in the coastal waters (both fresh and brackish) of the Yucatan Peninsula, in Mexico and Belize.

[2] This species was described by Carl Leavitt Hubbs in 1936 with the type locality given as 5 kilometres (3.1 mi) east of Progreso, Yucatán, Mexico.

[4] The name of the genus commemorates the American ichthyologist Samuel Garman (1843-1927) who was working on a revision of his 1895 monograph on the Cyprinodontidae at the time of his death.

It is mainly herbivorous, its diet largely being made up of microalgae, but it also eats small invertebrates such as ostracods, tanaidacea, and amphipods.