Molecular characterization of Indian species of the genus Cornudiscoides Kulkarni, 1969 (Monogenoidea: Dactylogyridae)

Abstract

Molecular characterization and phylogenetic study based on partial sequences of 28S and 18S ribosomal DNA (rDNA) of sixteen Indian species of the genus Cornudiscoides (Monogenoidea: Dactylogyridae) were conducted to decode the genetic relationship between them and with other members of the family Dactylogyridae. Blastn searches disclosed the significant similarity among the species of the Cornudiscoides for large ribosomal subunits as well as for small ribosomal subunit showing genetic relatedness. The phylogenetic tree using neighbour-joining (NJ) and minimum evolution (ME) methods for 28S ribosomal subunit depicted that all Cornudiscoides species clustering in a single clade and forming sister clade with other members of the family Dactylogyridae and similar results were obtained from 18S ribosomal subunit. Thus, the present study demonstrated that both 28S and 18S ribosomal subunits are very helpful in discriminating Cornudiscoides species (intra or interspecific variation) and in the establishment of the evolutionary relationship among them.