Denison’s barb gets a new name


In continued tidying of the catch-all genus that is Puntius, two fish have now been renamed as Sahyadria: S. denisonii and S. chalakkudiensis.

Readers of a scientific bent, interested in the long-winded specifics of the morphometric data on the fish can find the full report of how they have been identified.

The more everyday fishkeepers will know S. denisonii as the Red lined torpedo barb, a species now classed as critically endangered through a variety of factors including habitat degradation, range restriction, and over collection for the hobby. In the last five years, some 300,000 fish have been collected and exported. Within the genera, six evolutionarily distinct lineages have been traced, all endemic to the Western Ghats region of India.

Red lines were originally placed tentatively in Puntius, though it was noted originally that the two species had a "strikingly different coloration and mouth shape to all other congeners and are likely to warrant placement in a separate genus in the future" (Pethiyagoda et al. 2012).

Now, based on osteological (osteology is the anatomical study of bones) and molecular evidence, Raghavan et al demonstrate that Redlines comprise a distinct genus. The genus sits close to Dawkinsia, with which some S. denisonii have formerly been cross-bred, to create a golden variant.

For those who have never seen S. chalakkudiensis, the key differences involve the intensity and length of the red stripe (greater in both respects on S. denisonii) and the position of the mouth. S. denisonii has a subterminal (slightly downward, forward facing) mouth, where S. chalakkudiensis has an inferior (clearly downward facing) mouth.

Farming efforts have helped to reduce the pressures on wild caught fish, and it’s strongly advised that aquarists query the source of these fish before committing to buying them.

The proposal for the new name comes from Rajheev Raghavan et al from India’s Conservation Research Group, and appears in the November 26 Journal of Threatened Taxa.

Why not take out a subscription to Practical Fishkeeping magazine? See our latest subscription offer.

Don't forget that PFK is now available to download on the iPad/iPhone.