Redescription of Ligophorus mediterraneus Sarabeev, Balbuena & Euzet, 2005 (Monogenea: Ancyrocephalidae) with some methodological notes

A redescription of Ligophorus mediterraneus Sarabeev, Balbuena & Euzet, 2005, based on original material from the Black and Mediterranean Seas, is presented and new diagnostic characters for its recognition are proposed. The unlikely wide range of variation in the angle between the shaft and point of the anchors, reported for this species and for some others in the genus, is analysed, and the structure of the ventral bar in Ligophorus spp. is described and its taxonomic significance discussed.