Introduction
"Fishes of the genus Devario Heckel were first reported from Sri Lanka by describing two species of Danio, D. lineolatus and D. micronema (Bleeker 1863). While Bleeker’s subsequent illustrations (1864: fig. 2 & 3) (Fig. 1) suggest that they represent two distinct species; Günther (1868: 282) treated them as a single species endemic to Sri Lanka, noting that “Dr. Bleeker, l.c. distinguishes two species from Ceylon—an elevated form, D. lineolatus, with L. lat. 37 and A. 17–18, and an elongate form with L. lat. 34 and A. 15–16. These differential characters do not hold good, and happen to be exactly reversed in our specimens.” Günther (1868) described a further new species, Eustira ceylonensis, from Sri Lanka for which he also created the new genus Eustira (treated as a synonym of Devario by Fang (2003)).

Day (1878) recognized from Sri Lanka only a single species of Devario (then Danio), which he identified as D. malabaricus (Jerdon 1849), and in the synonymy of which he placed D. micronema, while recognizing D. ceylonensis as valid (but in Perilampus). Silas (1957), however, showed that D. ceylonensis is in fact, a synonym of D. malabaricus.

Hora and Nair (1941) placed D. malabaricus in the synonymy of D. aequipinnatus (McClelland 1839), an action that was adopted by some authors of the Sri Lankan ichthyofauna (e.g., Munro 1955; Mendis and Fernando 1962), while others (e.g. Pethiyagoda 1991) paradoxically recognized both D. malabaricus and D. aequipinnatus from the island. Meanwhile, Kottelat and Pethiyagoda (1990) described Danio pathirana, a barred Devario from southern Sri Lanka, whose distinctive colour pattern immediately distinguished it from the striped Sri Lankan fishes identified as D. malabaricus and D. aequipinnatus by authors. Based on a study of topotypical specimens of both species, Jayaram (1991) showed them to be markedly different, with D. malabaricus restricted to southern India and Sri Lanka.

The number of species of Sri Lankan Devario and their identity are thus in need of clarification and, to this end we made an extensive sampling of Devario populations from many parts of the island. An examination of this collection, and also of specimens previously collected by the Wildlife Heritage Trust, show that at least six species of Devario exist in Sri Lanka. Here, in addition to redescribing the previously known species of Sri Lankan Devario, we describe these two new species."