Rana pipiens. Modern studies reject Lithobates, returning the genus back to Rana.

Reference:
Zhi-Yong Yuan, Wei-Wei Zhou, Xin Chen, Nikolay A. Poyarkov, Hong-Man Chen, Nian-Hong Jang-Liaw, Wen-Hao Chou, Nicholas J. Matzke, Koji Iizuka, Mi-Sook Min, Sergius L. Kuzmin, Ya-Ping Zhang, David C. Cannatella, David M. Hillis, Jing Che; Spatiotemporal Diversification of the True Frogs (Genus Rana): A Historical Framework for a Widely Studied Group of Model Organisms, Systematic Biology, Volume 65, Issue 5, 1 September 2016, Pages 824–842, https://doi.org/10.1093/sysbio/syw055