The Mahseer belongs to the genus Tor, of which there are several subspecies to be found in India and in other range countries in South Asia. There are issues regarding the taxonomy of the Mahseer and despite advances in molecular biology and tools for DNA analysis, scientists are not entirely in agreement as to how many sub species exist.
The Mahseer is a large cyprinid (belonging to the carp family) and is recognized by its large scales along the lateral line with two pairs of barbels. Males are identified by their long pectoral fins and have been known to reach a length of 2.7 m and weigh well over 100 lbs (though these sizes are rarely seen nowadays). The species is migratory; moving upstream during rains. It prefers clean, fast flowing and well oxygenated waters and has a much lower fecundity rate (lays less eggs per kg of body weight) than most carps.