The subspecies is named after I. R. P. Heslop, who claimed in 1945 to have shot a pygmy hippo in the Niger Delta region and collected several skulls.
O nome da subespecie deriva de I. R. P. Heslop, que afirmaba, en 1945, haber cazado un hipopótamo pigmeo na rexión do delta do Río Níxer e coleccionar varios cranios.