The Lepocreadiidae (Digenea) of fishes of the north-east Atlantic: review of the genera Opechona Looss, 1907 and Prodistomum Linton, 1910

The genera Opechona Looss and Prodistomum Linton are redefined: the latter is re-established, its diagnostic character being the lack of a uroproct. Pharyngora Lebour and Neopechona Stunkard are considered synonyms of Opechona, and Acanthocolpoides Travassos, Freitas & Bührnheim is considered a synonym of Prodistomum. Opechona bacillaris (Molin) and Prodistomum [originally Distomum] polonii (Molin) n. comb. are described from the NE Atlantic Ocean. Separate revisions with keys to Opechona, Prodistomum and ‘Opechona-like’ species incertae sedis are presented. Opechona is considered to contain: O. bacillaris (type-species), O. alaskensis Ward & Fillingham, O. [originally Neopechona] cablei (Stunkard) n. comb., O. chloroscombri Nahhas & Cable, O. occidentalis Montgomery, O. parvasoma Ching sp. inq., O. pharyngodactyla Manter, O. [originally Distomum] pyriforme (Linton) n. comb. and O. sebastodis (Yamaguti). Prodistomum includes: P. gracile Linton (type-species), P. [originally Opechona] girellae (Yamaguti) n. comb., P. [originally Opechona] hynnodi (Yamaguti) n. comb., P. [originally Opechona] menidiae (Manter) n. comb., P. [originally Pharyngora] orientalis (Layman) n. comb., P. polonii and P. [originally Opechona] waltairensis (Madhavi) n. comb. Some species are considered ‘Opechona-like’ species incertae sedis: O. formiae Oshmarin, O. siddiqii Ahmad, 1986 nec 1984, O. mohsini Ahmad, O. magnatestis Gaevskaya & Kovaleva, O. vinodae Ahmad, O. travassosi Ahmad, ‘Lepidapedon’ nelsoni Gupta & Mehrotra and O. siddiqi Ahmad, 1984 nec 1986. The related genera Cephalolepidapedon Yamaguti and Clavogalea Bray and the synonymies of their constituent species are discussed, and further comments are made on related genera and misplaced species. The new combination Clavogalea [originally Stephanostomum] trachinoti (Fischthal & Thomas) is made. The taxonomy, life-history, host-specificity and zoogeography of the genera are briefly discussed.     

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.     

New species of Prodistomum Linton, 1910 (Digenea: Lepocreadiidae) from the longtail bass, Hemanthias leptus (Ginsburg, 1952) in the Bay of Campeche, Gulf of Mexico

Prodistomum lichtenfelsi n. sp. (Digenea: Lepocreadiidae) is described; it was obtained from the intestine of the longtail bass, Hemanthias leptus (Ginsburg), collected from the Bay of Campeche in the Gulf of Mexico. This is the first record of a parasite from this host. Prodistomum lichtenfelsi n. sp. is similar to P. hynnodi, P. menidiae, and P. waltairensis in that it possesses a prepharynx that is distinctly shorter (153 microm [110-210] long) than the combined length of the esophagus (163 microm [110-220] long) and the pseudoesophagus (137 microm [120-170] long), but it differs from them in having an excretory vesicle that extends into the forebody, a smooth ovary and testes, and vitellaria that extend to the posterior level of the esophagus. An updated key to the 12 nominal species within Prodistomum is given, and the diagnosis of the genus is emended to include species possessing a sinuous external seminal vesicle.     

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.     

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.     

Two new species of Enenterum Linton, 1910 (Digenea) in the marine fish Neoscorpis lithophilus (Kyphosidae) from the south-western Indian Ocean

Enenterum elsti sp. nov. and E. prudhoei sp. nov. are described from the intestine of Neoscorpis lithophilus off Mapelane, Natal, South Africa. These species differ from others of the genus Enenterum in the ratio of oral sucker to body-length and in the length of the prepharynx. E. elsti differs from E. prudhoei in size, in sucker-ratio and in the number and configuration of the oral lobes. A key to the species of Enenterum is presented and the status of the genus briefly discussed.     

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.     

Faustulid trematodes (Digenea) from marine fishes of Australia

Twelve species of faustulid trematode are described or redescribed from Australian marine fishes. Bacciger lesteri Bray, 1982 and B. sprenti Bray, 1982 are redescribed from Selenotoca multifasciata from Moreton Bay. It is suggested that the original host record for these species, Mugil sp., was incorrect. The genera Discogastroides, Odontocotyle and Pseudodiscogasteroides are synonymised with Paradiscogaster. The new combinations Paradiscogaster arabi (Hafeezullah & Siddiqi, 1970), P. hainanensis (Shen, 1970), P. indicus (Srivastava, 1939), P. macrostomus (Shimazu & Kamegai, 1990), P. ostracii (Yamaguti, 1934) and P. pritchardae (Gupta & Ahmad, 1978) are proposed. Discogasteroides hawaiensis Hanson, 1955 is synonymised with P. ostracii. P. macrostomus and P. ostracii are redescribed from Ostracion meleagris and O. cubicus from the Great Barrier Reef. P. farooqii Hafeezullah & Siddiqi, 1970 is redescribed from Monodactylus argenteus from Moreton Bay. The following new species are described: P. machidai n. sp. from Pomacanthus semicirculatus and P. sexstriatus from the Great Barrier Reef, P. dweorg n. sp. from Meuschenia galii, P. lobomyzon n. sp. from Tilodon sexfasciatus and P. habilis n. sp. from Pelates octolineatus, all from Western Australia. Antorchis pomacanthi (Hafeezullah & Siddiqi, 1970) Machida, 1975 is redescribed from Pomacanthus semicirculatus and P. sexstriatus from the Great Barrier Reef. The new combination Antorchis intermedius (Madhavi, 1975) is proposed for Parantorchis intermedius. Parayamagutia ostracionis is redescribed from O. cubicus from the Great Barrier Reef. Trigonocryptus conus is redescribed from Arothron hispidus from South-east Queensland and from A. nigropunctatus from the Great Barrier Reef. The new combination Trigonocryptus australiensis (Kurochkin, 1970) is proposed for Pseudodiscogasteroides australiensis. The Echinobrevicecinae is reduced to synonymy with the Faustulidae.     

Hemiuridae (Digenea) from marine fishes of the Great Barrier Reef,Queensland, Australia

The following species are described, figured and/or recorded from the Great Barrier Reef at Heron Island or Lizard Island, Queensland, with comparative material reported from other areas of the ocean around Australia or New Guinea: Dinurus longisinus (new synonym: D. hippuri) from Seriola lalandi, Heron Island and Coryphaena hippurus, Papua New Guinea; Ectenurus trachuri from Caranx sexfasciatus, Diploprion bifasciatus, Pterocaesio marri, Seriola lalandi and Atherinomorus capricorniensis, Heron Island; Erilepturus hamati (with 25 new synonyms) from Lutjanus carponotatus, Lizard Island, Platycephalus bassensis, Coff's Harbour, NSW, P. fuscus, Coff's Harbour, NSW and Moreton Bay, Queensland, P. endrachtensis, Sillago analis, S. maculata, S. ciliata, Pseudorhombus arsius and Polydactylus sp. from Moreton Bay, Queensland and Lates calcarifer, Darwin, Northern Territory; Tubulovesicula angusticauda from Echeneis naucrates and Lethrinus miniatus, Heron Island and Anguilla reinhardtii, Moreton Bay and Bribie Island, Queensland; Elytrophalloides humerus from Trachinotus botla and T. coppingeri, Heron Island; Lecithochirium kawakawa from Euthynnus affinis Heron Island and Lizard Island: Lecithochirium cirrhiti (new synonyms: L. sammarae, L. nohu) from Sargocentron rubrum, Heron Island; Lecithochirium caesionis from Pterocaesio marri, heron Island; Plerurus digitatus (new synonyms: P. cynoglossi, P. atulis, P. scomberomori) from Plectropomus leopardus, Heron Island, Lutjanus erythropterus, Variola louti, Scomberomorus semifasciatus, Grammatorcynus bicarinatus and Carangoides embureyi, C. gymnostethoides, Lizard Island, Scomberomorus commerson, Heron Island, Lizard Island, New Britain, Papua New Guinea, Point Lookout, Queensland and Moreton Bay, Queensland, Euthynnus affinis Heron Island, Lizard Island and New Britain, Papua New Guinea, Sphyraena barracuda, Heron Island and Lizard Island, Scomberomorus munroi, S. queenslandicus and Saurida undosquamis, Moreton Bay, Queensland and Chirocentrus dorab, Bundaberg, Queensland. The Lecithochirium species-group Cirrhiti is considered indistiguishable from the species-group Lotellae.     

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.     

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.     

The genus Deretrema Linton, 1910 (Digenea: Zoogonidae) from southern Great Barrier Reef fishes,with a description of Deretrema woolcockae n. sp.

Two species of Deretrema (Zoogonidae) are reported from labrid fishes from the Great Barrier Reef. D. nahaense Yamaguti, 1942 is recorded from the gall-bladders of the labrids Thalassoma hardwicke (Bennett), T. jansenii (Bleeker), T. lunare (Linnaeus) and T. lutescens (Lay & Bennett). This species is recognised, despite having been formerly synonymised with D. pacificum Yamaguti, 1942. In addition to morphological distinction, D. nahaense appears to have strict host-specificity for the genus Thalassoma. D. woolcockae n.sp. is described from the gallbladder of Hemigymnus fasciatus (Bloch). The new species is close to D. acutum Pritchard, 1963 and D. plotosi Yamaguti, 1940, but differs slightly in the distribution of the vitelline follicles, the sucker-ratio and the position of the cirrus-sac. In addition, this species also appears to have a distinct host-specificity, being restricted to one labrid species.     

Two species ofCoitocaecum Nicoll, 1915 (Digenea: Opecoelidae) from Moreton Bay,Queensland, Australia

Two species ofCoitocaecum Nicoll, 1915,C. gymnophallum Nicoll, 1915 andC. michaeli n. sp., are recorded, described and figured from the intestine ofAcanthopagrus australis from Moreton Bay, off south east Queensland. The holotype ofC. gymnophallum Nicoll, 1915 is examined, measured and figured for comparison.C. glandulosum Yamaguti, 1934 andC. robustum Wang, 1984 are reduced to synonymy withC. gymnophallum. The host specificity ofCoitocaecum spp. is discussed.     

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.     

Prodistomum priedei n. sp. (Digenea: Lepocreadiidae) from the deepwater cardinalfish Epigonus telescopus (Perciformes: Epigonidae) in the northern Atlantic Ocean

Prodistomum priedei n. sp. is described from Epigonus telescopus from the Porcupine Seabight. It differs from its closest relatives, P. waltairensis, P. hynnodi and P. alaskensis (Ward & Fillingham, 1934) n. comb. [originally Opechona], in its relatively smaller ventral sucker and smaller eggs. Other differentiating features are tabulated. Attention is drawn to the host-parasite relationship associating a lepocreadiine lepocreadiid with a perciform host, a relationship which is common in warm shallow waters but unusual in cold deep-sea conditions. This may indicate that host and parasite have colonised the deep sea simultaneously and co-evolved in that environment.     

The Australian species of Lobatocreadium Madhavi, 1972, Hypocreadium Ozaki, 1936 and Dermadena Manter, 1945 (Digenea: Lepocreadiidae), parasites of marine tetraodontiform fishes

The genera Lobatocreadium, Pseudocreadium, Hypocreadium and Dermadena are redefined and host lists given. Provisional keys to species of Lobatocreadium, Hypocreadium and Dermadena are presented. The following species are described from (1) the Great Barrier Reef: Lobatocreadium exiguum from Balistapus undulatus and Sufflamen bursa; Hypocreadium cavum n. sp. from Abalistes stellatus (type-host) and Cantheschenia grandisquamis; H. grandisquamis n. sp. from Cantheschenia grandisquamis; Dermadena spatiosa n. sp. from Cantheschenia grandisquamis; and (2) southwestern Australia: D. stirlingi n. sp. from Meuschenia hippocrepis. The following new combinations are made: Lobatocreadium vitellosum (Ozaki, 1936) n. comb. (originally Leptocreadium); Hypocreadium balistes (Nagaty, 1942) n. comb. (originally Pseudocreadium); H. biminensis (Sogandares-Bernal, 1959) n. comb. (originally Pseudocreadium); H. indicum (Madhavi, 1972) n. comb. (originally Pseudocreadium); and H. galapagoensis (Manter, 1945) n. comb. (originally Pseudocreadium). Several nominal species of Pseudocreadium and Hypocreadium are considered incertae sedis.     

Amphicreadium n. g. (Digenea: Lepocreadiidae) from monacanthid fishes (Tetraodontiformes) from the coast of northern Tasmania

A new lepocreadiid genus, Amphicreadium, is erected for the species A. denspeniculus n. sp. from Acanthaluteres vittiger and for an unnamed species from Meuschenia freycineti, both from off northern Tasmania. The new genus is distinguished from all other members of its family by its amphistomatous body plan.     

New hosts for Helicometrina nimia Linton, 1910 (Digenea: Opecoelidae) in the south-center coast of Chile

Two new hosts (Calliclinus geniguttatus and Calliclinus nudiventris) for Helicometrina nimia are reported from Chile. Comments concerning geographical distribution of H. nimia and diet of marine fish hosts are given.     

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.     

Opecoelidae (Digenea) from western Mediterranean fishes: three rare species

Three little-known opecoelid digeneans from marine fishes off Corsica, France, are redescribed and their relationships discussed. Plagioporus novella Maillard & Lambert, 1978 from Conger conger is transferred to Podocotyle as P. novella (Maillard & Lambert, 1978) n. comb. The new combinations Podocotyle tohei (Yamaguti, 1970) and P. congeri (Yamaguti, 1970) are formed for species originally assigned to Plagioporus. Podocotyle temensis Fischthal & Thomas, 1970 from Epinephelus guaza is redescribed and compared with the other Podocotyle species reported from the Mediterranean. A third species, Pseudopecoeloides chloroscombri (Fischthal & Thomas, 1970) n. comb. (was Podocotyloides), is redescribed from three Trachurus species and a key to the species of this Pseudopecoeloides is given.