Ectoparasites face a daily challenge: to stay connected to their hosts. Polyopisthocotylean monogeneans typically attach to the surface of fish gills mistreatment extremely specialised structures, the sclerotized clamps. additionally, genera inside the family Protomicrocotylidae have either clamps of the “gastrocotylid” or the “microcotylid” sorts; this perplexed systematists as a result of these clamp types square measure characteristic of distinct, major teams. The ascertained pattern of genetic variation inferred by nuclear DNA Internal Transcribed Spacer one (ITS1) and mtDNA cytochrome enzyme one (COI), between parasite populations is possibly caused by a recent shared demographic history sort of a reduced species space within the last geological period. Monogeneans will infect the skin and gills, leading to irritations to the host. significant infections might end in erratic swimming behavior. Affected gills might become irritated and swollen. attributable to the oioxenous host specificity of the many monogenean species, the (geological) continuance and also the biological science distribution of their hosts, the approach used inside the framework of this study relies on the generic instead of the species level.