Ceylonese Dwarf Rasbora

Rasboroides vaterifloris is distinguished from its congener R. nigromarginatus by the location of pelvic-fin origin which is midway between the pectoral-fin base and anal-fin origin (vs. closer to anal-fin origin), by having the dorsal margin of the operculum more or less straight (vs. with a deep indentation), and the dorsal profile of the head approximately straight (vs. slightly concave) behind the level of the eye in males. Males of R. vaterifloris can be diagnosed from those of R. nigromarginatus by having a greater interorbital width (29-33 % HL, vs. 17-22) and a greater internarial width (19-21 % HL, vs. 11-17), while females differ by having a greater anal-fin depth (23.5-24.8 % SL, vs. 17.4-22.7), a greater interorbital width (25-33 % HL, vs. 16-21), a greater caudal-peduncle depth (12.4-13.4 % SL, vs. 10.4-12.3) and a lesser caudal-peduncle length (18.6-21.2 % SL, vs. 21.1-25.0). It differs from R. pallidus and R. rohani by having the dorsal-fin origin 1 scale-width (vs. 3 scale-widths) behind the pelvic-fin origin and alesser body depth of 31.0-32.8 % SL (vs. 33.0-37.5 in R. pallidus and 33.3-40.0 in R. rohani) (Ref. 94541).

Nematode Infestation. Parasitic infestations (protozoa, worms, etc.)

Bacterial Infections (general). Bacterial diseases

A prolific breeder. The courtship ritual is frenetic; several batches of about 20 eggs are spawned among submerged marginal vegetation during the course of about 30 minutes. The eggs sink, and hatch in about 36 hours. The free-swimming fry are very delicate and sensitive to water conditions.

Dorsal soft rays (total): 10; Analsoft rays: 8 - 9; Vertebrae: 29

Occurs in shallow, cool, clear, quiet, heavily shaded forest streams, usually with a silty substrate and often in areas with a large amount of leaf debris in the water. Feeds on terrestial insects (Diptera and Coleoptera, see Ref. 6469) and detritus.

Occurs in shallow, cool, clear, quiet, heavily shaded forest streams, usually with a silty substrate and often in areas with a large amount of leaf debris in the water. Feeds on terrestrial insects (Diptera and Coleoptera, see Ref. 6469) and detritus. Males slimmer and brightly colored than females.

fisheries: of no interest; aquarium: commercial

Rasboroides vaterifloris, known as the pearly rasbora, vateria flower rasbora or fire rasbora, is a species of freshwater cyprinid fish endemic to Sri Lanka. It can be found in the shallow waters of shaded, slow-flowing clear streams with a silt substrate. It also prefers areas with plentiful leaf debris. Its diet consists of detritus and terrestrial insects. This species can reach a length of 4 centimetres (1.6 in) TL. It can also be found in the aquarium trade.

R. vaterifloris was formerly believed to be the only species in the genus and found in several river basins. A study in 2013 found that it was restricted to the Kalu River basin, with related species inhabiting other basins. However, a comprehensive taxonomic review in 2018 based on morphometry, meristics and mtDNA found that one of the species recognized in 2013, R. nigromarginatus (also restricted to the Kalu River basin), is a junior synonym of R. vaterifloris. Although this expands its range in the Kalu River basin, R. vaterifloris is more threatened than the relatively widespread R. pallidus.