The Little Arkansas River extends 102 miles through south-central Kansas to its confluence with the Arkansas River at Wichita. Historical studies along the most urban reach of this river at Wichita reported 12 unionid species. Unionid mussel surveys were conducted at 250 sites within the Little Arkansas River basin in 1978–79. Along the reach at Wichita, seven species were found alive: Lasmigona complanata, Leptodea fragilis, Potamilus ohiensis, Pyganodon grandis, Quadrula pustulosa, Quadrula quadrula, and Uniomerus tetralasmus. In 2008–09, surveys were conducted at the Wichita sites between 11th Street North and 109th Street North. Live representatives of five of these species were detected, missing P. ohiensis and U. tetralasmus. An exotic species, Corbicula fluminea, first was reported in the 2008–09 study. Mussel abundance in the current study was significantly lower than in the 1978–79 survey. In addition, there was a significantly different species distribution in this reach between the two surveys. Mussel length class frequency was not significantly different between surveys for any of the mussel species. A combination of environmental changes during the urban development of this river reach may have caused the decline in mussel populations.