Tonlesapia amnica Ng & Rainboth 2011

Tonlesapia amnica differs from its only congener, T. tsukawakii, in having the infraorbital canal extending beyond (vs. not reaching) ventral margin of orbit, a more slender body (7.2–13.5% SL vs. 14.3–15.0) and caudal peduncle (4.4–5.2% SL vs. 5.1–6.3), a smaller eye (6.5–8.3% SL vs. 8.7–9.2) and more dorsal-fin rays (9–10 vs. 8) (Ref. 87929).

The Song Hau Giang which is a branch of the Mekong River also known as the Bassac River is fairly clear, slow flowing (current about 0.2 ms-1) and wide (2 km) with a sand and silt bottom. This species has also been collected from brackish habitats and is the third species of Indo-Pacific callionymid known to inhabit freshwaters (the other species being Callionymus fluviatilis and T. tsukawakii).

The Song Hau Giang which is a branch of the Mekong River also known as the Bassac River is fairly clear, slow flowing (current about 0.2 ms-1) and wide (2 km) with a sand and silt bottom. This species has also been collected from brackish habitats and is the third species of Indo-Pacific callionymid known to inhabit freshwaters (the other species being Callionymus fluviatilis and T. tsukawakii) (Ref. 87929).