Rasboroides pallidus (Deraniyagala 1958)

Rasboroides pallidus differs from R. vaterifloris and R. nigromarginatus by having dorsal-fin origin 3 (vs. 1) scale-widths behind pelvic-fin origin and body depth of 34.3-37.5 % SL in males, 33.0-36.7 in females (vs. 31.1-32.8 in males and 31.0-31.7 in females of R. vaterifloris, and 28.2-33.0 in males and 26.9-29.1 in females of R. nigromarginatus). It can be differentiated from male R. rohani by having a smaller size of up to 24.6 mm SL (vs. up to 35.5 mm SL), having 1/2 6 1/2 or 1/2 7 1/2 (vs. 1/2 8 1/2) scales in transverse line on body, 20-24 (vs. 25-28) scales in lateral series on body, and 2 (vs. 1) lateral processes to the kinethmoid. Female R. pallidus differs from female R. rohani by possessing a greater eye diameter (39-40 % HL, vs. 29-34) and a greater interorbital width (33-36 % HL, vs. 25- 28) (Ref. 94541).

Dorsal soft rays (total): 10; Analsoft rays: 9; Vertebrae: 28 - 29

Found in shallow, slow-flowing, densely shaded lowland rain-forested streams with a sandy-siltsubstrate (Ref. 94541).

Rasboroides pallidus is a species of freshwater cyprinid fish endemic to southwestern Sri Lanka. It is only known from shallow, slow-flowing streams in the basins of the Kalu River, Bentara River, Gin River, Polathu-Modera River and Nilwala River. It has been introduced to the Mahaweli and Walawe River basins, and is overall less threatened than the related R. vaterifloris.

A comprehensive taxonomic review in 2018 based on morphometry, meristics and mtDNA disputed the validity of R. rohani, showing that it is a junior synonym of R. pallidus; this synonymy is followed by the Catalog of Fishes but not the FishBase.

It can grow to 3.6 cm (1.4 in) standard length.