Table 1 Species used in molecular phylogenetic analysis with information of their host, locality and GenBank accession numbers

Cercaria duplicata ^a

Anodonta anatina

Lake Saravesi, Finland

KJ729516 [27]

KJ740490 [27]

C. duplicata ^a

A. anatina

Kaunas Water Reservoir, Lithuania

KJ729515 [27]

KJ740492 [27]

C. duplicata ^a

A. anatina

River Chesnava, Russia

KJ729514 [27]

KJ740491 [27]

C. duplicata ^a

A. anatina

River Sluch, Ukraine

KJ729517 [27]

KJ740489 [27]

Phyllodistomum folium

Esox lucius

River Ild, Russia

KJ729542, KJ729545 [27]

KJ740499, KJ740500 [27]

P. folium

Rutilus rutilus

Rybinsk Water Reservoir on River Volga, Russia

KJ729536 [27]

KJ740501 [27]

P. folium

Aspius aspius

Rybinsk Water Reservoir on River Volga, Russia

KJ729548 [27]

KJ740503 [27]

P. folium

Abramis ballerus

Rybinsk Water Reservoir on River Volga, Russia

KJ729539 [27]

KJ740502 [27]

P. folium

Abramis brama

Rybinsk Water Reservoir on River Volga, Russia

KJ729537, KJ729547 [27]

KJ740505 [27]

P. folium

Gymnocephalus cernuus

River Shumorovka, Russia

KJ729552 [27]

KJ740506 [27]

P. folium ^b

G. cernuus

River Chesnava near Rybinsk Water Reservoir on River Volga, Russia

KX957727, KX957728

KY307880–KY307883

P. folium ^b

G. cernuus

Curonian Lagoon, Lithuania

KX957729

KY307884, KY307885

P. folium

Cottus gobio

River Nėris, Lithuania

KJ729550 [27]

KJ740507 [27]

P. folium

Gasterosteus aculeatus

River Vilnelė, Lithuania

AY277707 [62]

AY277705 [62]

P. folium ^a

Sphaerium corneum

River Shumorovka, Russia

KJ729546 [27]

KJ740498 [27]

P. folium ^a

S. corneum

River Hegga, Norway

KJ729549, KJ729551 [27]

KJ740494, KJ740495 [27]

P. folium ^a

Pisidium supinum

River Ūla, Lithuania

KJ729544 [27]

KJ740496 [27]

P. folium ^a

Pisidium amnicum

River Loo Jõgi, Estonia

KJ729541 [27]

P. folium ^a

P. amnicum

River Ild, Russia

KJ729535 [27]

KJ740497 [27]

P. folium ^a

P. amnicum

River Siilaisenpuro, Finland

KJ729533 [27]

Phyllodistomum umblae

Coregonus albula

Lake Syamozero, Karelia, Russia

KJ729528 [27]

KJ740508, KJ740509, KJ740510 [27]

Phyllodistomum angulatum

Sander lucioperca

River Chesnava, Russia

KJ729529, KJ729530, KJ729531 [27]

KJ740511, KJ740512 [27]

P. angulatum ^b

S. lucioperca

Rybinsk Water Reservoir on River Volga, Russia

KX957734, KX957735

P. angulatum ^b (= Phyllodistomum megalorchis)

Lota lota

Rybinsk Water Reservoir on River Volga, Russia

KX957733

KY307870, KY307871

Phyllodistomum pseudofolium ^b

G. cernuus

River Chesnava near Rybinsk Water Reservoir on River Volga, Russia

KX957727, KX957731, KX957732

KY307875, KY307876–KY307879

P. pseudofolium ^a (= Phyllodistomum sp. of Ginetzinskaya, 1959)

P. amnicum

River Chesnava, Russia

KJ729527 [27]

KJ740513 [27]

P. pseudofolium ^ab (= Phyllodistomum sp. of Ginetzinskaya, 1959)

P. amnicum

Pond near Rybinsk Water Reservoir on River Volga, Russia

KX957730

KY307874

Phyllodistomum sp.^b (identified as

P. pseudofolium)

Perca fluviatilis

Rybinsk Water Reservoir on River Volga, Russia

KY307869

KY307886

Phyllodistomum macrocotyle ^a

Dreissena polymorpha

Lake Vilkokšnis, Lithuania

KJ729518, KJ729522, KJ729526 [27]

KJ740518, KJ740519 [27]

P. macrocotyle ^a

D. polymorpha

Elektrėnai Water Reservoir, Lithuania

KJ729525 [27]

KJ740516 [27]

P. macrocotyle ^a

D. polymorpha

Lake Wigry, Poland

KJ729520 [27]

KJ740520, KJ740521, KJ740522 [27]

P. macrocotyle ^a

D. polymorpha

River Shumorovka, Russia

KJ729521, KJ729524 [27]

KJ740523 [27]

P. macrocotyle ^a (= P. folium sensu Sinitsin, 1905)

D. polymorpha

Lake Lepelskoe, Belarus

AY288828 [63]

AY288831 [63]

P. macrocotyle ^a (= P. folium sensu Sinitsin, 1905)

D. polymorpha

Lake Lukomskoe, Belarus

AF533015 [63]

AF533015 [63]

P. magnificum

Tandanus tandanus

Moggill Creek, Queensland, Australia

KF013186, KF013189 [53]

KF013153, KF013156 [53]

P. inecoli

Heterandria bimaculata

Agua Bendita, Xico, Veracruz, Mexico

KC760199 [8]

P. inecoli

Profundulus sp.

Rio Templo, San Juan del Rio, Mexico

KM659389 [10]

P. spinopapillatum

Profundulus balsanus

Rio PuebloViejo, San Gabriel Mixtepec and Rio Santa Cruz, Santiago Jamiltepec, Mexico

KM659382, KM659388 [10]

P. centropomi

Centropomus parallelus

Tlacotalpan, Veracruz, Mexico

KM659384 [10]

P. kanae

Hynobius retardatus

Pippu, Hokkaido, Japan

AB979868 [7]

P. brevicecum

Umbra limi

Brokenhead, Manitoba, Canada

KC760204 [8]

P. cf. symmetrorchis

Clarias gariepinus

Lake Victoria, Kenya

KF013174 [53]

KF013162 [53]

P. vaili

Mulloidichthys flavolineatus

Lizard Island, Queensland, Australia

KF013173 [53]

KF013155 [53]

P. hoggettae

Plectropomus leopardus

Lizard Island, Queensland, Australia

KF013191 [53]

KF013148 [53]

Pseudophyllodistomum johnstoni ^a

Macrobrachium australiense

Warrill Creek, Queensland, Australia

KF013177 [53]

KF013166 [53]

Gorgodera cygnoides

Rana ridibunda

Switzerland

AF151938 [64]

G. cygnoides

R. ridibunda

Kokaljane, near Sofia, Bulgaria

AY222264 [65]

G. amplicava

R. catesbeiana

Nebraska, USA

FJ445743 [66]

Gorgoderina attenuata

R. clamitans

Nebraska, USA

FJ445741 [66]

G. simplex

R. clamitans

Nebraska, USA

FJ445742 [66]

Xystretrum solidum

Sphoeroides testudineus

Conch Key, Florida, USA

KF013188 [53]

KF013149 [53]

Xystretrum sp.

Sufflamen fraenatum

Ningaloo, Western Australia, Australia

KF013160 [53]

Nagmia floridensis

Rhinoptera bonasus

Gulf of Mexico, East Ship Island, Mississippi, USA

AY222262 [65]

Cercariaeum crassum ^a

P. amnicum

River Žeimena, Lithuania

GU462117 [67]

Maritrema arenaria ^a

Semibalanus balanoides

Belfast Lough, Northern Ireland

HM584171 [68]