Abstract
Specimens of Austropotamobius pallipes were found to support Branchiobdella italica, B. parasita, B. astaci, and B. hexodonta, either alone or in a combination, in Piedmont, Liguria, Lombardy, Emilia and Friuli‐Venezia Julia. The American Cambarincola mesochoreus occurs on the introduced Lousiana red swamp crayfish, Procambarus (S.) clarkii, also in Piedmont. A taxonomic key to the species reported in northern Italy is given.