The Spiny Loach is a small freshwater fish native to Sri Lanka and widely distributed throughout South Asia. In Sri Lanka, it is commonly found in streams, ponds, marshes, rice fields, irrigation canals, and slow-moving sections of rivers. It prefers shallow waters with soft sandy or muddy bottoms, dense aquatic vegetation, and leaf litter, where it can burrow into the substrate for protection. This peaceful bottom-dwelling fish is mainly active during the evening and night, spending much of the day hidden beneath the sand or among aquatic plants. It feeds on insect larvae, worms, tiny crustaceans, algae, detritus, and other small organisms found in the sediment. Like other loaches, it possesses small defensive spines beneath its eyes, which are used for protection against predators. The Spiny Loach is an important native species in Sri Lanka’s freshwater ecosystems, contributing to the health of bottom habitats by feeding on small invertebrates and organic matter. Its presence is often an indicator of healthy freshwater environments with good water quality and natural vegetation.