Diplomystes chilensis, the tollo or tollo de agua dulce, is a species of freshwater ray-finned fish belonging to the family Diplomystidae, the velvet catfishes. This fish is endemic to Chile where it is found in the area of Valparaiso and Santiago. It grows to a maximum total length of . This species was previously considered to be extinct but in 2000 it was reported that two specimens had been collected from the Rio Cachapoal in the Rapel basin.