Opistholobetines (Digenea: Opecoelidae) in Australian tetraodontiform fishes

Opistholebetine opecoelids are reported following examination of 1,041 individual tetraodontiform fishes, comprising 60 species and seven families, collected in Australian waters between 1986 and 2018. Nine species consistent with Opistholebes Nicoll, 1915, Heterolebes Ozaki, 1935 or Maculifer Nicoll, 1915 were recovered. However, phylogenetic analysis of sequence data, generated for some of these species, suggested that five genera, not three, are required to adequately accommodate these taxa. Thus, the concept and composition for each is revised, Pseudoheterolebes Yamaguti, 1959 nec Gupta, 1968 is resurrected and Parallelolebes n. g. is proposed. Of the nine species examined, five are new. Four new species are from fishes endemic to subtropical and temperate Australian waters for which no trematodes have previously been reported: Pa. australis n. sp. and Ps. corazonae n. sp. from the slender-spined porcupinefish Diodon nicthemerus Cuvier (Diodontidae) off Stanley, Tasmania; Pa. virilis n. sp. from the horse-shoe leatherjacket Meuschenia hippocrepis (Quoy & Gaimard) (Monacanthidae) off Stanley; and Ps. stellaglobulus n. sp. from the threebar pocupinefish Dicotylichthys punctulatus Kaup (Diodontidae) in Moreton Bay, south-east Queensland. The fifth new species is M. diodontis n. sp., collected from the spotted porcupinefish Diodon hystrix Linnaeus and the blackblotched porcupinefish D. liturosus Shaw, in tropical waters on the Great Barrier Reef. Species reported previously include the type-species of Opistholebes, O. amplicoelus Nicoll, 1915 from the rough golden puffer Lagocephalus lunaris (Bloch & Schneider) (Tetraodontidae) and the common toadfish Tetractenos hamiltoni (Richardson) (Tetraodontidae) in Moreton Bay, and three species reported for the first time from fishes in Australian waters: H. maculosus Ozaki, 1935, Pa. elongatus Ozaki, 1937 n. comb. and Ps. diodontis (Cable, 1956) n. comb., each from both D. hystrix and D. liturosus on the Great Barrier Reef. Following the revisions, Opistholebes is recognised for two species, Heterolebes for five, Maculifer for eight, Pseudoheterolebes for five and Parallelolebes for three.     

Two Lepotrema Ozaki, 1932 species (Digenea: Lepocreadiidae) from marine fishes from the southern Great Barrier Reef, Queensland, Australia

The genus Lepotrema Ozaki, 1932 is revived and redefined. Its main diagnostic characters are the dorsal excretory pore, the muscular development of the distal metraterm and the trilobate ovary. It is considered to contain five species, to which a key is given. Lepotrema clavatum Ozaki, 1932 is briefly redescribed from Amanses scopas and Sufflamen chrysopterus, and L. canthescheni n. sp. is described from Cantheschenia grandisquamis, based on material from the southern Great Barrier Reef. L. canthescheni is distinguished by its vitelline and uterine distribution. The other three recognised species are: L. adlardi (Bray, Cribb & Barker, 1993) n. comb., L. incisum (Hanson, 1955) n. comb. and L. xanthichthydis (Yamaguti, 1970) n. comb., all three having originally been placed in Lepocreadium.     

Two species of Prodistomum Linton, 1910 (Digenea: Lepocreadiidae) from marine fishes of Australia

Prodistomum angelae (Kruse, 1981) n. comb. [originally Lepocreadium] is redescribed from the type-host, Scorpis georgiana, from off southwestern Western Australia. P. keyam n. sp. is described from Monodactylus argenteus from off southeastern Queensland. It differs from other members of the genus in its short ejaculatory duct. The genus Prodistomum Linton is discussed and redefined, and an updated key and record list of the nine recognised species are given.     

Eight species of Lintonium Stunkard & Nigrelli, 1930 (Digenea: Fellodistomidae) in Australian tetraodontiform fishes

Systematic Parasitology - We report eight species of Lintonium from tetraodontiform fishes from Australian waters and describe six of them as new. Two species are described from tetraodontids from...     

Description of three species of Holorchis Stossich, 1901 (Digenea: Lepocreadiidae) from marine fishes off Corsica

Three species of Holorchis are redescribed from marine fishes from off Corsica. They are: Holorchis pycnoporus from Diplodus vulgaris, D. sargus, Lithognathus mormyrus, Pagellus erythrinus, Sparus pagrus and Symphodus roissali; H. micracanthum from Sparus pagrus and Pagellus erythrinus; and H. legendrei from Mullus surmuletus. The characteristics differentiating these species are discussed, in particular those separating H. pycnoporus and H. legendrei, species which previously have been considered synonyms. The internal morphology of the cirrus-sac differs distinctly between these forms, which also have microhabitat and host differences.     

Lepocreadiidae (Digenea) of Australian coastal fishes: new species of Opechona Looss, 1907, Lepotrema Ozaki, 1932 and Bianium Stunkard, 1930 and comments on other species reported for the first time or poorly known in Australian waters

Opechona austrobacillaris n. sp. is described from Pomatomus saltatrix from marine sites off Western Australia and New South Wales, Australia. It differs from O. bacillaris in its elongate outline, small ventral sucker, longer pseudoesophagus (relative to the oesophagus), relatively shorter ventral sucker to ovary distance and the relatively longer post-testicular region. Lepotrema monile n. sp. is described from Pomacentrus wardi from Heron Island, Queensland. It differs from its congeners in the sphincter around the distal metraterm and the more-or-less oval ovary. Bianium spongiosum n. sp. is described from Ostracion cubicus from Lizard Island, Queensland. It differs from its congeners in lacking lateral flaps in the forebody, but in having large, internal spongiform patches in the lateral forebody. The following species are redescribed from Australian sites: Lepocreadium oyabitcha from Abudefduf whitleyi, Lizard Island; Clavogalea trachinoti from Trachinotus botla, Heron Island and T. coppingeri, New South Wales, Stradbroke Island, Queensland and Heron Island; Myzoxenus insolens from Notolabrus parilus, Western Australia; Bulbocirrus aulostomi from Aulostomus chinensis, Heron Island; Lepocreadioides orientalis [new synonyms: Bicaudum interruptum Bilqees, 1973; Lepocreadioides interruptum (Bilqees, 1973) Madhavi, Narasimhulu & Shameem, 1986; Lepocreadioides discum Wang, 1986; Lepocreadioides sp. of Karyakarte & Yadav (1976)] from Cynoglossus bilineata, Moreton Bay, Queensland; Hypocreadium patellare from Sufflamen chrysopterus, Heron Island; Echeneidocoelium indicum from Echeneis naucrates, Heron Island; Multitestis pyriformis from Epinephelus cyanopodus, Heron Island; Pseudopisthogonoporus vitellosus from Naso brevirostris, Heron Island; and Bianium hispidum from Torquigener whitleyi and T. pleurogramma, southern Queensland. Only M. solens and M. pyriformis have been reported from Australian waters before; both are new host records.     

The status of Petalocotyle Ozaki, 1934 (Digenea: Gyliauchenidae), including the description of two new species from acanthurid fishes in Queensland,Australia

The status of Petalocotyle Ozaki, 1934 within the Gyliauchenidae Goto & Matsudaira, 1918 is reviewed. Two new species, P. adenometra from Prionurus microlepidotus (Amity Point, Queensland, Australia) and P. diverticulata from Acanthurus nigrofiuscus and A. lineatus (Heron Island, Queensland, Australia), are described. The body plan of Petalocotyle conforms to that of members of the Gyliauchenidae (oral sucker absent, well-developed pharynx, complex oesophagus and characteristic male terminal genitalia), indicating justifiable inclusion in this family. A new diagnosis is given for the genus, such that Petalocotyle is now identified by the presence of an anterior, protuberant ventral sucker, long caeca, a large, sigmoid cirrus-sac containing a coiled ejaculatory duct, and an extensive vitellarium. We suggest that, of all the known genera of gyliauchenids, Petalocotyle may most closely resemble the 'archaetypal gyliauchenid', that is, it may be placed basally within the radiation of the Gyliauchenidae. However, derived characters, like diverticula in the reproductive system, indicate that some characters of individual members of Petalocotyle may be considered advanced and do not reflect an archaetypal condition. Parallels in the structure of the male and female genitalia of Robphildollfusium Paggi & Orecchia, 1963 and Petalocotyle, along with the shared morphology of the digestive tract, indicate possible phylogenetic links between the two genera. This affinity is difficult to infer using morphology alone and recommend that Robphildollfusium remain detached from the Gyliauchenidae.     

Three species of Pycnadenoides Yamaguti, 1938 (Digenea: Opecoelidae), including two new species from temperate marine fishes of Australia

Pycnadenoides pagrosomi Yamaguti, 1938 and P. reversati n. sp. from Pagrus auratus (Sparidae) and P. invenustus n. sp. from Nemadactylus valenciennesi (Cheilodactylidae) are described from the temperate marine waters off south-west Western Australia and south-east Queensland. The difference in the anterior extent of the vitelline follicles observed in P. reversati n. sp. recovered from off south-east Queensland waters and the material from off Western Australia is discussed. P. reversati n. sp. is distinguished from P. pagrosomi mainly in the position of the genital pore and in the arrangement of the testes, and from P. invenustus n. sp. in the posterior extent of the cirrus-sac. P. reversati belongs to the group of species with a short cirrus-sac and P. invenustus to the group with the cirrus-sac reaching into the anterior hindbody.     

Rhopalotrema (Digenea: Didymozoidae), a new genus from Australian platycephalid fishes

Rhopalotrema n. g. is erected to accommodate two new species of didymozoid collected from platycephalid fishes from South-east Queensland, Australia and is assigned to the subfamily Didymozoinae. Rhopalotrema elusiva n. sp. is described from the fins of Platycephalus fuscus and R. pterygionastes n. sp. is described from the fins of P. indicus. The new genus is similar to Neometadidymozoon, but is distinguished from it by the structure of the testes, which are convoluted and extend from near the anterior end of the hindbody to a point only a short distance into the forebody. The two new species are distinguished from each other by their size and the size and shape of the oral sucker and pharynx.     

The Lepocreadiidae (Digenea) of pomacentrid fishes (Perciformes) from Heron Island,Queensland, Australia

The following lepocreadiid species are described from pomacentrid fishes from the Southern Great Barrier Reef at Heron Island, Queensland: Lepocreadium adlardi n. sp. from Abudefduf bengalensis; L. clavatum from Acanthochromis polyacanthus and Parma polylepis; Lepocreadium sp. from Amblyglyphidodon curacao; Lepocreadium sp. from Pomacentrus cf. wardi; Preptetos xesuri (new synonyms: P. caballeroi, P. pritchardae Toman, 1989 nec Ahmad, 1984) from Parma polylepis plus the acanthurid Naso annulatus; and P. cannoni from Pomacentrus bankanensis.     

The Lepocreadiidae (Digenea) of fishes from the north-east Atlantic: review of the genus Neolepidapedon Manter, 1954, with a description of N. smithi n. sp.

A new species, Neolepidapedon smithi, is described from the fish Mora moro in the north-eastern Atlantic Ocean and is distinguished from other members of the genus. It differs from its congeners in the extension of the vitellarium into the forebody and/or the body shape. The genus Neolepidapedon is reviewed and a key to species given. The genus has previously contained up to 20 species, but is here restricted to eight species, which possess a very thick male duct wall within the cirrus-sac, a narrow internal seminal vesicle, an excretory vesicle restricted to the hindbody and no eye-spots. The remaining nominal species with a relatively thin-walled internal male duct, a globular internal seminal vesicle, an excretory system which reaches into the forebody and eye-spots are considered to belong to a separate group which is related to Opechona. Some of these species were included by Yamaguti (1971) in his new subgenus Neolepidapedon (Neolepidapedoides), which is raised to full generic status. Eight new combinations are made: Neolepidapedoides belizensis (Fischthal, 1977), N. dollfusi (Durio & Manter, 1968), N. equilatum (Siddiqi & Cable, 1960), N. hypoplectri (Nahhas & Cable, 1964), N. israelense (Fischthal, 1980), N. macrum (Overstreet, 1969), N. medialunae (Montgomery, 1957) and N. mycteropercae (Siddiqi & Cable, 1960).     

Lepidapedon spp. (Digenea: Lepocreadiidae) from deep-sea gadiform fishes of the NW Atlantic Ocean,including four new species

Five species are described from fishes in deep waters of the northwestern Atlantic Ocean: Lepidapedon gaevskayae n. sp. from Coryphaenoides (Nematonurus) armatus; L. merretti n. sp. from Phycis chesteri; L. zubchenkoi n. sp. from Coryphaenoides (Chalinura) leptolepis; L. beveridgei n. sp. from C. (N.) armatus; and Lepidapedon sp. innom. from Antimora rostrata. The genus Lepidapedon is discussed and divided into groups of species distinguished by the vitelline distribution and the extent of excretory vesicle. The new species are placed in their appropriate groups and differentiated from the other species in the group.     

Trichodinid parasites (Ciliophora: Peritricha) from the gills of some Australian marine fishes

Three species of the genus Trichodina are reported from the gills of marine fishes in south-eastern Tasmania, Australia. Two of these species are new: T. australis n. sp. from five atherinid fish species, Atherinosoma microstoma, Leptatherina presbyteroides, Kestratherina brevirostris, K. esox and K. hepsetoides; and T. nesogobii n. sp. from Nesogobius sp. 1. One previously reported species, T. jadranica Raabe, 1958, was also found on Nesogobius sp. 1.     

The Lepocreadiidae (Digenea) of fishes from the north-east Atlantic: a review of the genusLepidapedon Stafford, 1904

The genusLepidapedon is subdivided into several species groups and subgroups of species based on the vitelline distribution and the length of the excretory vesicle. The species in each of the subgroups are listed and keys to the species in most subgroups are given. The following north-eastern Atlantic species are described or redescribed:Lepidapedon rachion fromMelanogrammus aeglefinus, Gadus morhua, Aspitrigla cuculus, Merlangius merlangus andPollachius pollachius; L. cambrensis fromEnchelyopus cimbrius; L. sommervillae n. sp. fromTrachyrincus scabrus, T. murrayi andCoryphaenoides guentheri; L. elongatum fromGadus morhua; L. gaevskayae fromCoryphaenoides (Nematonurus) armatus; L. discoveryi n. sp. fromCoryphaenoides (Nematonurus) armatus; L. arlenae n. sp. fromTrachyrincus scabrus andT. murrayi; L. mariannae n. sp. fromGaidropsarus argentatus; Lepidapedon spp. innom (Elongatum-group) fromCoryphaenoides guentheri andCoryphaenoides (Chalinura) leptolepis; L. desclersae n. sp. fromLepidion eques; L. beveridgei fromCoryphaenoides (Nematonurus) armatus andC. (Chalinura) mediterraneus; andL. zubchenkoi fromCoryphaenoides (Chalinura) leptolepis andC. (C.) profundicolus. The phylogeny, host-specificity and zoogeography of the genus are briefly discussed.     

The Lepocreadiidae Odhner, 1905 (Digenea) of fishes from the north-east Atlantic: summary paper,with keys and checklists

Results published in seven previous papers on the Lepocreadiidae are summarised and keys are given to the 19 species of lepocreadiid parasite from north-eastern Atlantic fishes. Diagnoses for the family and the two subfamilies represented in the north-eastern Atlantic are presented. Parasite-host and host-parasite lists, arranged in taxonomic order, are given. The NE Atlantic fauna is dominated numerically by members of the subfamily Lepidapedinae, which occur most frequently in gadiform fishes, often in the deep-sea.The three lepocreadiine forms are parasites of cosmopolitan fishes or fish families that predominate in warm waters.     

The Opecoelidae (Digenea) of sparid fishes of the western Mediterranean. I. Pachycreadium Manter, 1954

Problems of the systematics of the Opecoelidae in the Mediterranean region are discussed. The genus Pachycreadium Manter, 1954 is redefined and its validity commented upon. Pachycreadium carnosum (Rud., 1819) is described from Sparus pagrus and Pagellus erythrinus off Corsica (Scandola) and compared with P. gastrocotylum (Manter, 1940) and P. lerneri Sogandares-Bernal, 1959.

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Résumé Les problèmes concernant la systématique des Opécoelidés de la région méditerranéenne sont abordés. Les auteurs redéfinissent et discutent la validité du genre Pachycreadium Manter, 1954. Pachycreadium carnosum (Rudolphi, 1819) est décrit à partlr d'exemplaires parasites de Sparus pagrus et de Pagellus erythrinus des côtes de Corse (Scandola), puis comparé à P. gastrocotylum (Manter, 1940) et à P. lerneri Sogandares-Bernal, 1959.

     

Three species of plagioporine opecoelids (Digenea), including a new genus and two new species,from marine fishes from off the coast of Chile

Villarrealina peruanus (syn. Pirupalkia queulensis) is described from Cilus gilberti, off the Talcahuano region, Chile. It is considered an opecoelid and is distinguishable by the combination of its extensive uterus, which reaches to the posterior extremity, and the vitellarium restricted to the hindbody. Jerguillicola leonora n. g., n. sp. from Aplodactylus punctatus, off the Talcahuano region, Chile, is distinguished by the uterus reaching into the post-testicular region, the lack of a seminal receptacle, the eggs attached together is strings formed by a matrix, the large cirrus-sac filled mainly with fairly dense connective tissue, a long coiled seminal vesicle and a long coiled ejaculatory duct. Neolebouria georgenascimentoi n. sp. from Pinguipes chilensis and Prolatilus jugularis, off the Talcahuano region, Chile, can be distinguished from its congeners by a its elongate cirrus-sac and oblique entire to weakly lobed testes.     

<Emphasis Type="Italic">Lepotrema</Emphasis> Ozaki, 1932 (Lepocreadiidae: Digenea) from Indo-Pacific fishes,with the description of eight new species,characterised by morphometric and molecular features

We review species of the genus Lepotrema Ozaki, 1932 from marine fishes in the Indo-West Pacific. Prior to the present study six species were recognised. Here we propose eight new species on the basis of combined morphological and molecular analysis: Lepotrema acanthochromidis n. sp. ex Acanthochromis polyacanthus from the Great Barrier Reef (GBR); Lepotrema hemitaurichthydis n. sp. ex Hemitaurichthys polylepis and H. thompsoni from Palau and French Polynesia; Lepotrema melichthydis n. sp. ex Melichthys vidua from Palau and the GBR; Lepotrema amansis n. sp. ex Amanses scopas from the GBR; Lepotrema cirripectis n. sp. ex Cirripectes filamentosus, C. chelomatus and C. stigmaticus from the GBR; Lepotrema justinei n. sp. ex Sufflamen fraenatum from New Caledonia; Lepotrema moretonense n. sp. ex Prionurus microlepidotus, P. maculatus and Selenotoca multifasciata from Moreton Bay; and Lepotrema amblyglyphidodonis n. sp. ex Amblyglyphidodon curacao and Amphipron akyndynos from the GBR. We also report new host records and provide novel molecular data for two known species: Lepotrema adlardi Bray, Cribb & Barker, 1993 and Lepotrema monile Bray & Cribb, 1998. Two new combinations are formed, Lepotrema cylindricum (Wang, 1989) n. comb. (for Preptetos cylindricus) and Lepotrema navodonis (Shen, 1986) n. comb. (for Lepocreadium navodoni). With the exception of a handful of ambiguous records, the evidence is compelling that the host-specificity of species in this genus is overwhelmingly oioxenous or stenoxenous. This renders the host distribution in three orders and ten families especially difficult to explain as many seemingly suitable hosts are not infected. Multi-loci molecular data (ITS2 rDNA, 28S rDNA and cox1 mtDNA) demonstrate that Lepotrema is a good generic concept, but limited variability in sequence data and differences in phylogenies produced for different gene regions make relationships within the genus difficult to define.     

Two new species of Neolebouria Gibson, 1976 (Digenea: Opecoelidae) from temperate marine fishes of Australia

Neolebouria moretonensis n. sp. is described from Gerres subfasciatus (Gerreidae) from Moreton Bay, south-east Queensland and N. lineatus n. sp. is described from Centroberyx lineatus (Berycidae) from off Rottnest Island, south-west Western Australia. C. lineatus represents a new host family and order (Beryciformes) for the genus. The two new species are distinguished within the genus by their entire, tandem to oblique testes and cirrus-sacs that do not extend into the hind-body, by being less than 1 mm in length, and by the position of the genital pore and the relative size of the forebody and post-testicular region. N. lineatus and N. moretonensis are very similar but are distinguished by their caeca which extend further posteriorly in N. moretonensis. There is no apparent pattern in the host-specificity of this genus.