First report of a gryporhynchid tapeworm (Cestoda: Cyclophyllidea) from New Zealand and from an eleotrid fish, described from metacestodes andin vitro-grown worms

Abstract

Metacestodes are often found in the body cavity of the common bully (Gobiomorphus cotidianus McDowall), from freshwater habitats in Otago, New Zealand. Identification of metacestodes relies only on the number, size and shape of the rostellar hooks. To attempt species determination, we cultivated metacestodes in vitro for up to 23 days, during which they matured to at least the male stage of development, although female organs were not discernable. Identified as members of the genus Paradilepis Hsü, 1935 (family Gryporhynchidae), these specimens are compared to previously described species, in particular P. minima (Goss, 1940), from Australia, the closest species, both geographically and morphologically. Although the size of scolex, suckers and proglottids differ significantly from those of P. minima, we are cautious about interpreting 'adults' grown in vitro, because we are unsure whether the artificial conditions alter development. For this reason, and because of the lack of female organs, we refrain from erecting a new species, and refer to the specimens as Paradilepis cf. minima until such time as the adults are found in the definitive host. With this proviso we present here a description of the in vitro-grown worms and the metacestodes as a preliminary study of this cestode. A molecular analysis of small subunit (SSU) rDNA sequences, shows the position of P. cf. minima and another gryporhynchid, Neogryporhynchus cheilancristrotus (Wedl, 1855), to be equivocal, but confirms their exclusion from the Dilepididae and Hymenolepididae. This is the first record of a gryporhynchid from New Zealand, and the first from the fish family Eleotridae.

Galactosomum otepotiense n. sp. (Trematoda: Heterophyidae) infecting four different species of fish-eating birds in New Zealand: genetically identical but morphologically variable

“…is most closely related to species from Australia. This pattern is seen in several species of parasitic helminth (Presswell et al , 2012; Cribb et al , 2014b; Georgieva et al , 2017; Huston et al , 2018), and is perhaps unsurprising when considering that Australia is the closest large land mass and much of New Zealand's marine avifauna has evolved from Australian immigrant species or vice versa (e.g. Diamond, 1984; Given et al , 2005).…”

Phylogenetic relationships of the family Gryporhynchidae (Cestoda: Cyclophyllidea) inferred through SSU and LSU rDNA sequences

“…As adults, gryporhynchids parasitize the intestines of fish-eating birds across the globe. Recently, molecular and morphological phylogenetic hypotheses showed that the family Gryporhynchidae is a monophyletic group nested within the Cyclophyllidea (Mariaux, 1998; Hoberg et al ., 1999a; Presswell et al ., 2012; Mariaux et al , 2017), but these studies were based on a few species. The phylogeny inferred in the present study includes a much greater diversity of gryporhynchids (20 species representing 9 of 16 described genera).…”

“…We used the software Clustal W (Thompson et al ., 1997) for the alignment of the sequences of species of adult gryporhynchid tapeworms and for the species Paradilepis cf. minima (SSU; larva from fish – see Presswell et al ., 2012); Amirthalingamia macracantha (Joyeux & Baer, 1975); Neogryporhynchus lasiopeius Baer & Bona, 1960; Paradilepis maleki Khalil, 1961; Paradilepis scolecina (Rudolphi, 1819); Paradilepis sp. ; Parvitaenia sp.…”

Parasites of the Neotropic cormorant Nannopterum (Phalacrocorax) brasilianus (Aves, Phalacrocoracidae) in Chile

“…Adults of the genus Paradilepis Hsü, 1935 are parasites of Pelecaniformes and, in many cases, cormorants (Presswell et al, 2012). It consists of fourteen species, Paradilepis delachauxi Fuhrmann, 1909, Paradilepis diminuta Huey & Dronen, 1981, Paradilepis kempi Southwell, 1921, Paradilepis longivaginosus Mayhew, 1925, Paradilepis maleki Khalil, 1961, Paradilepis urceina Bona, 1975, Paradilepis phalacrocoracis Ukoli, 1968, Paradilepis minima Goss, 1914, Paradilepis patriciae Baer & Bona, 1960, Paradilepis rugovaginosus Freeman, 1954, Paradilepis scolecina Rudolphi, 1819, Paradilepis simoni Rausch, 1949, Paradilepis urceus Wedl, 1855, and P. caballeroi (Presswell et al, 2012.…”