Sundadanio retiarius is a species of freshwater ray-finned fish belonging to the family Sundadanionidae, the tiny danios.

[3] It is endemic to Kalimantan, Indonesian Borneo, and known from the Kotawaringin and Kahayan River drainages.

It lives in peat swamps and blackwater streams.

[1] Sundadanio retiarius reaches a maximum size of 1.9 cm (0.75 in) standard length.

[4]