Influence of host habitat on the occurrence of gill monogeneans Pseudodactylogyrus spp. on wild Japanese eels Anguilla japonica

Pseudodactylogyrus anguillae (Yin & Sproston, 1948) from the giant mottled eel Anguilla marmorata Quoy & Gaimard, 1824, in the Phongolo River, South Africa: an invader on the African continent

The global invasive anguillid gill parasite Pseudodactylogyrus anguillae (Yin and Sproston, 1948) has only recently been documented from eels in South Africa. As there is no known eel trade in South Africa, the source of introduction of this parasite has been debated, and its status as an alien parasite was rendered uncertain. We report on the first infection of Pseudodactylogyrus anguillae from the giant mottled eel Anguilla marmorata from the Phongolo River (South Africa) using classic morphological and molecular methodologies and clarify the introduction status category of this parasite as alien and invasive.

Three new species of Pseudodactylogyrus (Monogenea: Pseudodactylogyridae) from Australian eels

Three species of Pseudodactylogyrus Gusev, 1965 (Monogenea: Pseudodactylogyridae) were collected from the gills of Anguilla reinhardtii Steindachner and A. australis Richardson from several localities in Australia and eels imported to Japan from Australia. Pseudodactylogyrus gusevi sp. n. from A. reinhardtii (type host) and A. australis in Queensland, Australia is most similar to P. bini (Kikuchi, 1929), but can be differentiated by the shorter male copulatory tube, heavy sclerotisation of the vaginal tube and the presence of a small projection of the supplementary piece of the hamulus. Pseudodactylogyrus rohdei sp. n. from A. australis (type host) in Queensland, Australia is most similar to P. anguillae (Yin et Sproston, 1948), but differs in the possession of a longer cement gland and the presence of a small projection on the supplementary piece of the hamulus. Pseudodactylogyrus bini sensu Gusev, 1965 and P. anguillae sensu Gusev, 1965 are synonymised with P. gusevi sp. n. and P. rohdei sp. n., respectively. Pseudodactylogyrus mundayi sp. n. from A. australis, originating in Tasmania, Australia and sent alive to Japan, is most similar to P. kamegaii Iwashita, Hirata et Ogawa, 2002, from which it can be discriminated by the shorter male copulatory tube and the shorter vaginal tube. Dactylogyrus bialatus Wu, Wang et Jian, 1988 from Synechogobius ommaturus (Richardson) (Gobiidae) is transferred to Pseudodactylogyrus as P. bialatus comb. n. A phylogenetic tree based on the ITS2 region of six species of Pseudodactylogyrus including P. gusevi and P. mundayi shows that P. haze from a goby diverged first, and that species from eels are monophyletic, forming three lineages differing by their zoogeographical distribution. With the three new species and one new combination proposed in this paper, Pseudodactylogyrus is now comprised of eight species infecting anguillid and gobiid fish, and a key to species is presented.