Scanning electron microscopy of scale microstructures in Channa barca, a poorly known snake head fish in regard to taxonomy

Scanning electron microscopy has been identified as an important approach in studying scale microstructures in fish with reference to taxonomy. In this article, a detailed microstructural analysis of the scales of Channa barca, a poorly known snakehead fish was carried out the location of focus, inter-radial distance, average width and inter-circular space of anterior circulii; inter-circular distance and dentition in lateral circulii; the shape, spacing, length of lepidonts in anterior circulii and the number and width of radii were compared with those of a related species, Channa aurantimaculata. The location of the focus was found to be similar to those of the gachua group of the genus Channa but was different from those of the marulius group. There were major similarities-though with a few notable differences-in scale microstructures between C. barca and the aforementioned closely related species C. aurantimaculata, indicating that scale microstructure analysis has the potential to distinguish even closely related fish species. While several of the microstructural features of the scale were found to be similar to those of the gachua group, others were closer in nature to those of the marulius group. Some microstructural characteristics, however, were found to be totally different from those of both gachua and marulius groups. All of these characteristic features of scale microstructure in C. barca are discussed with reference to taxonomic significance.