Records of opecoeline species Pseudopecoelus cf. vulgaris and Anomalotrema koiae Gibson & Bray, 1984 (Trematoda, Opecoelidae, Opecoelinae) from fish of the North Pacific, with notes on the phylogeny of the family Opecoelidae

Abstract

AbstractOpecoelid speciesPseudopecoelus cf.vulgarisandAnomalotrema koiaeGibson & Bray, 1984 were found in fish collected in the boreal waters of the North Pacific.Pseudopecoelus cf.vulgarisdiffers fromPseudopecoelusvulgaris(Manter, 1934) in terms of the egg size. This is the first record ofA. koiaein the North Pacific, and the second ofPseudopecoeluscf.vulgaris.Previously,A. koiaewas recorded only in North Atlantic fish. Partial sequences of 28S rDNA obtained for these two species and six other previously unsequenced representatives of the family Opecoelidae were analysed together with data from GenBank. Phylogenetic analysis supports the allocation of the six clades of opecoelids – Helicometrinae, Opecoelinae, Opistholebetinae, ‘freshwater Plagioporinae’, ‘marine Plagioporinae B’ and ‘marine Plagioporinae C’, and confirms the paraphyly of the group ‘deep-sea Plagioporinae’. Our phylogeny does not support previous hypotheses about the monophyly of opecoelines with a uroproct.