The recent discovery of three new fish species has re-emphasized the importance of the Manimala river flowing through Central Kerala as a biodiversity hotspot of freshwater fishes.
The three new species, Puntius nelsoni, Systomus chryseus, and Systomus rufus , have been reported from three locations in Pathanamthitta district by Mathews Plamoottil, Assistant Professor in Zoology, Government College, Chavara.
Freshwater fishes
All the three belong to the Cyprinid family of freshwater fishes. While P.nelsoni has been discovered from Kallumkal, near the point where the Manimala river merges with the Pampa, S.chryseus has been reported from the riverbed of Keezhvaipur, a place near Mallappally, and S.rufus from Venpala, near Thiruvalla.
A detailed article describing the new species has been published in the latest issue of the International Journal of Fauna and Biological Studies . Yellowish in colour, P.nelsoni is characterised by a short snout, wide mouth, a spindle-shaped mark on the back of the head and an elongated black band on the bony flap covering the gills.
A golden coloured fish, S.chryseus has an elongated pectoral fin.
Sporting deep red fins, S.rufus owes its name to the Latin word Rufus , meaning red coloured.
According to the article, most of the freshwater fishes in Kerala described in the past were from rivers north of Kochi. Taxonomic studies on fishes of rivers in the southern parts of the State are rare.
Noting that all the new fish species reported recently have been discovered from the Manimala river, the article says it indicates the importance of the river as a biodiversity hotspot.
Originating in the Western Ghats, the river flows through Kottayam and Pathanamthitta before joining the Pampa river at Muttar, near Thiruvalla. Prof. Mathews has reported a fourth new species, Puntius nigronotus , from Mananthavady.
The fish is characterised by a black dorsal fin and higher number of lateral line scales.
According to Prof. Mathew, it is after 150 years that a new species of the genus Systomus is being discovered in Kerala.
The specimens have been deposited in the Government Museum of the Zoological Society of India at Kolkata and Kozhikode.
