A new species, Lecidella oceanica Lu L. Zhang & Xin Y. Wang, is described here. The new species has been collected from the southwest coast of South Korea and is characterized by small, subimmersed or sessile apothecia, colorless hypothecium and the presence of capistratone, isoarthothelin and thiophanic acid. We also report L. asema is for the first time from South Korea and new localities for L. enteroleucella. Lecideine, saxicolous lichens, taxonom