Key to Korean Gammarus species with calceoli on antenna 2 (modified after Kim et al., 2010). 1. Uropod 3, both rami with plumose setae................................................................... 2 - Uropod 3, both rami without plumose setae................................... G. gageoensis Kim, Lee & Min, 2010 2. Uropod 3, inner ramus relatively short, length ratio of outer ramus to inner ramus less than 0.7; telson sparse, with short setae........................................................................ G. zeongogensis Lee & Kim, 1980 - Uropod 3, inner ramus relatively long, length ratio of outer ramus to inner ramus more than 0.7; telson setose, with long setae............................................................................ G. baengnyeongensis sp. nov.

Published as part of Kwon, So-Yeon, Kim, Min-Seop, Heo, Jun-Haeng & Kim, Young-Hyo, 2020, A new Gammarus species (Crustacea, Amphipoda, Gammaridae) from Northwestern Islands, South Korea, pp. 535-546 in Zootaxa 4896 (4) on page 545, DOI: 10.11646/zootaxa.4896.4.5, http://zenodo.org/record/4387901