Cyprinodon rubrofluviatilis
Cyprinodon rubrofluviatilis, known as the Red River pupfish, is a species of pupfish from the United States. It is found only in the Red River of the South and Brazos River drainages of Texas and Oklahoma. It grows to a total length of  and feeds on midge larvae and other insects. It was first described by Henry Weed Fowler in 1916, as a subspecies of the species Cyprinodon bovinus; the specific epithet  refers to the Red River. References

Further reading

rubrofluviatilis
Endemic fish of the United States
Freshwater fish of the United States
Brazos River
Red River of the South
Taxa named by Henry Weed Fowler
Fish described in 1916