Sundoreonectes is a small genus of stone loaches in the family Nemacheilidae, confined to fast-flowing streams on the island of Borneo. The atlas's two species, Sundoreonectes obesus and Sundoreonectes sabanus (the Borneo stone loach), occur in Malaysia and Indonesia and grow to only about 4 in as adults. Like other nemacheilids, they have an elongate, cylindrical body, a flattened underside, and small barbels around the mouth, adaptations for gripping and browsing along rocky or gravel stream beds in the clear, well-oxygenated, fast-current habitat typical of Sundaland's hill streams.
Neither species has an established presence in the aquarium trade; the genus is essentially of specialist and scientific interest rather than a hobby staple, and detailed husbandry accounts are sparse. Conservation status is mixed and concerning: Sundoreonectes sabanus is currently assessed as Endangered, while S. obesus remains Data Deficient, underscoring how little is documented about population trends for Borneo's stream-dwelling loaches even as the island's forested watersheds face ongoing pressure from logging and land conversion.