Kopsia rajangensis Borneo, Sarawak, Kapit, Upper Rejang River., Clemens & Clemens 21221 (BM) Borneo, Sarawak, Kapit, Upper Rejang River., Clemens & Clemens 21221 (NY) Borneo, Sarawak, Kapit, Upper Rejang River., Clemens & Clemens 21221 (BO) Isotype: Borneo, Sarawak, Kapit, Upper Rejang River., Clemens & Clemens 21221 (A) Holotype: Borneo, Sarawak, Kapit, Upper Rejang River., Clemens & Clemens 21221 (MO) Borneo, Sarawak, Kapit, Upper Rejang River., Clemens & Clemens 21221 (SAR)