Assigned developmental stages for the first 36 h postfertilization of Arkansas River Shiner Notropis girardi embryos and larvae, along with its associated time frame and a brief description that aided in identifying each stage. Hatching occurred between the caudal fin appearance stage and the otolith appearance stage. All work was conducted at Tishomingo National Fish Hatchery in Tishomingo, Oklahoma, on 26–27 July 2012.