Cymothoidae are big parasites on fishes and often they are host specific. This study reports that in India, the Black pomfret (Parastromateus niger), a highly edible marine fish belonging to the family Carangidae, is the type host of Cymothoa eremita (Isopoda, Cymothoidae). Among one hundred and sixty fish examined from April to July, 2010 in Parangipettai coastal waters, only three female specimens were infested in June, 2010. It seems that such parasitism depends particularly on the season and on the host sex.