Phylogenetic relationships within Dicrocoeliidae (Platyhelminthes: Digenea) from birds from the Czech Republic using partial 28S rDNA sequences.

Partial (D1-D3) 28S rRNA gene sequences from 16 isolates of digenean parasites of the family Dicrocoeliidae recovered from 16 bird species from the Czech Republic were used for phylogenetic reconstruction. Comparison with sequences available from GenBank suggests that the genus Brachylecithum is paraphyletic, requiring further validation and possible systematic revision. Although partial 28S rDNA is relatively conserved, analyses suggest that the following taxa are synonymous: Lutztrema attenuatum = L. monenteron = L. microstomum, Brachylecithum lobatum = B. glareoli. Zonorchis petiolatus is reassigned back to the genus Lyperosomum with L. collurionis as a junior synonym. The study revealed how complicated the systematics of the family Dicrocoeliidae is currently. The morphology of the group is variable, and the current distinguishing characters at species and even generic level are not sufficiently distinctive; it is difficult to identify the specimens correctly and identification of GenBank isolates is not reliable. Extensive sampling of isolates for both molecular and morphological studies is necessary to resolve the relationships within the family.