The blind cave eel (Ophisternon candidum) is a species of fish in the Synbranchidae family. It is endemic to subterranean waters in the Cape Range, Australia. Like other cave adapted fish such as Milyeringa (the only other vertebrates restricted to subterranean waters in Australia), the blind cave eel is entirely blind and lacks pigmentation. It is listed as vulnerable under the Australian Environment Protection and Biodiversity Conservation Act 1999. Reaching a length of 40 cm (16 in), it is the longest known cavefish. In its history of being listed by the IUCN since 1988, it has not been well known hence the Data Deficient status.