Channa kelaartii, a valid species of dwarf snakehead from Sri Lanka and southern peninsular India (Teleostei: Channidae)

The dwarf snakehead Channa gachua (Hamilton, 1822) (type locality Bengal) has been reported from a vast range, from Iran to Taiwan, and northern India to Sri Lanka. Here, adopting an integrative taxonomic approach, we show that the Sri Lankan snakehead previously referred to as C.gachua is in fact a distinct species, for which the name C.kelaartii (Günther, 1861) is available. Widely distributed in streams and ponds throughout Sri Lanka's lowlands, and also recorded here from the east-flowing drainages of southern peninsular India, C.kelaartii is distinguished from all the other species of the C.gachua species group by the combination of head shape, dorsal- and anal-fin ray counts, scale counts, the presence of pelvic fins, and live adult coloration. Further, C.kelaartii is genetically distinct from topotypical C.gachua by an uncorrected pairwise distance of 7.9–8.8 % for the mitochondrial cytochrome c oxidase subunit 1 (cox1) gene.