[2] The species was discovered in 2011, and was subsequently named and described by Mathews Plamoottil from the Baby John Memorial Government College, Chavara, Kollam, Kerala in 2014 in the International Journal of Fauna and Biological Studies.

[1][3] The Travancore yellow barb has so far only been recorded from the Manimala River which has its origin in Muthavara Hills of the Western Ghats, at 762m (2500 feet) above main sea level.

[1] The holotype ZSI/WGRC/IR/23 and 3 paratypes ZSI/ WGRC/ IR/ 2354 were found in the Kallumkal region of Manimala River, near Thiruvalla, in the Pattanamthitta District on 21 August 2011.

P. nelsoni can be distinguished from the rest of the species in its genus (Puntius) by the combination of uncommon characteristics such as the smaller snout, the short, feeble maxillaries which do not reach the orbit, nostrils placed halfway between the orbit and snout tip, the deeper head with a wider gape and the wide head.

[4] At the summit of occiput, there is a blue-green mark, and there are many fine black dots forming a thin band over the gills.