Tanichthys micagemmae is a species of freshwater ray-finned fish. It belongs in the mountain minnow family Tanichthyidae in the order Cypriniformes. It was only discovered in 2001, in a tributary of the Bến Hải River in Quảng Bình Province, Vietnam. Its range includes what was the demilitarized zone between North and South Vietnam and was subject to intense bombing during the Vietnam War.

It is similar in appearance to the White Cloud Mountain minnow (T. albonubes), the most familiar member of its genus, which is a commonly sold freshwater aquarium fish. T. micagemmae can be distinguished from its more familiar relative primarily by the lighter coloration of its lower body and by the centered position of its lateral stripes, compared with a position well above the middle in T. albonubes. Some older males develop spectacular elongated dorsal and anal fins.

The species is sold in England under the common name Vietnamese cardinal minnow.

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