The occurrence of an Australian leech species (genus Helobdella) in German freshwater habitats as revealed by mitochondrial DNA sequences.

The freshwater leech Helobdella europaea Kutschera 1987 was discovered twenty years ago in Germany and described as a new species. Here, we show that this leech is genetically identical with the Australian species Helobdella papillornata (CO-I-mt-DNA sequence identity of alignment positions: 98%). We conclude that H. europaea (syn. H. papillornata) represents an introduced annelid that occupies the same ecological niche as the common European leech H. stagnalis L.