Parasites are detrimental to host fitness and therefore should strongly select for host defence mechanisms. Yet, hosts vary considerably in their observed parasite loads. One notable source of inter-individual variation in parasitism is host sex. Such variation could be caused by the immunomodulatory effects of gonadal steroids. Here we assess the influence of gonadal steroids on the ability of...

Gyrodactylus aff. mugili Zhukov, 1970 (Monogenoidea: gyrodactylidae) is recorded and described from the gill lamellae of 11 of 35 greenback mullet, Chelon subviridis (Valenciennes) (minimum prevalence 31%), from the brackish waters of the shatt Al-Arab Estuary in southern iraq. the gyrodactylid was also found on the gill lamellae of one of eight speigler’s mullet, Valamugil speigleri (Bleeker),...

This study applies flexible statistical methods to morphometric measurements obtained via light and scanning electron microscopy (SEM) to discriminate closely related species of Gyrodactylus parasitic on salmonids. For the first analysis, morphometric measurements taken from the opisthaptoral hooks and bars of 5 species of gyrodactylid were derived from images obtained by SEM and used to assess...

The wageneri species group of Gyrodactylus contains the following molecularly confirmed salmonid parasites in Asia: taimeni Ergens, 1971, magnus Konovalov, 1967, brachymystacis 1978, and derjavini Mikhailov, 1975; Europe it following: derjavinoides Malmberg, Collins, Cunningham, Jalali, 2007, truttae Gläser, 1974, teuchis Lautraite, Blanc, Thiery, Daniel, Vigneulle, 1999, lavareti 1956, salveli...