During a 2014 aquatic species survey in the Medina River of the San Antonio River Basin of Texas, we located a reproducing population of the state-listed threatened golden orb (Quadrula aurea). In total, 124 live Q. aurea were recovered from a 200 m stretch of the river, and the length, height, and width of all specimens Q. aurea were recorded. Lengths ranged from 10–40 mm, with a mean length of 27 mm. Our findings represent the first modern (since 1970) record of a reproducing population of Q. aurea within the Medina River and indicate that this species could potentially be present in smaller tributaries and rivers throughout its range, and may be more widely distributed than previously thought. This information is significant as this species is currently under review for future federal protections by the United States Fish and Wildlife Service.