The Guadalupe darter (Percina apristis) is a small species of freshwater ray-finned fish, a darter from the subfamily Etheostomatinae, part of the family Percidae, which also contains the perches, ruffes and pikeperches. It is found in the Guadalupe River system in Texas. The Guadalupe darter was formally a subspecies of the dusky darter, but was recognized as an independent species in 2007. It is protected by state law as a threatened species.

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