The taxonomic and phylogenetic status of digeneans from the genusTimoniella(Digenea: Cryptogonimidae) in the Black and Baltic seas

Abstract

AbstractTimoniellaspp. are cryptogonimid flukes (Digenea: Cryptogonimidae) that parasitize the guts of fish in brackish waters.Timoniella imbutiforme, a species from the Mediterranean Sea, is recorded in the Black Sea, whileT. balthicahas been described from the Baltic Sea. In this paper, we clarify the taxonomic status ofTimoniellapopulations in the Baltic and Black seas. Adults and metacercariae ofTimoniellaspp. were sampled from localities in the Mediterranean Sea (France), Black Sea (Ukraine) and Baltic Sea (Germany) and subjected to molecular and morphological analysis, including Bayesian phylogenetic reconstruction based on concatenated sequences of ITS1–ITS2–28S. This allowed us to construct a new key to species of the genusTimoniella. Our results suggest thatT. balthicaforms part of the Boreal–Atlantic relict fauna of the Black Sea and should now be considered a junior synonym ofT. imbutiforme.