Odontomachus assiniensis is a species of ponerinae ant known as a trap-jaw ant. The trap-jaw mechanism consists of mandibles which spring shut when triggered. This ant was first described in 1892 by the Italian entomologist Carlo Emery. The type locality is the Ivory Coast, where the coastal site of Assini, in the southeast, gIves the specific name assiniensis, "of Assini".