author(s)
Sachin Pandit and Rani Dhanze

abstract
Commercially important species of the genus Labeo were collected from Gomati River (South Tripura) to study the abundance and taxonomic status, during the month of July- August 2017. While identifying the species, an abnormal specimen of Labeo bata without anal fin was recorded. The biometric comparison of morphometric and meristic data reveals that abnormal specimen significantly differs from normal population of 31 specimens disproportionately in respect of 18 characters out of 33 characters analysed. Snout length and inter orbital width are highly significant (0.039, 0.038) in head length, whereas eight characters are highly significant with standard length and the meristic character indicate that the aberrant specimen almost similar with normal specimen except circumpeduncular scale (15 vs. 19-21). The aberrations in specimen may be due to environmental degradation or some external injury in the juvenile stage which have developed deformities in respect of anal fin absence and also in different body proportions