Recently, momentous consideration has being given to our natural ecosystems due to toxic metals, insidious to our environment execute as pollutants to the freshwater ecosystems. The accumulations of metals were encompassed with lead, cadmium and chromium in organs of Devario aequipinnatus. Although, the microscopic scrutinization from the gill and liver of the fish species were explored, the crucial conditions of the ecosystem. The histological study plays a key role in determining the effects of pollution. In the length-weight relationships of the regression parameters of coefficient value r2, 'a' value and 'b' value were showed the negative allometric growth rate of species D. aequipinnatus. However, the nucleotide sequence blast search was performed in NCBI database. In that the species of D.aequipinnatus were closely associated with other sub-species but within same genus, and it showed the similarity range between 100% and 90% in reference to other species for phylogenetic analysis.
Keywords: D.aequipinnatus (Devario aequipinnatus); histology; length–weight relationship; phylogenetic analysis; toxic metals.