Parasitic nematodes of the genus Syphacia Seurat, 1916 infecting Cricetidae in the British Isles: the enigmatic status of Syphacia nigeriana.

Oxyurid nematodes (Syphacia spp.) from bank (Myodes glareolus) and field/common (Microtus spp.) voles, from disparate geographical sites in the British Isles, were examined morphologically and genetically. The genetic signatures of 118 new isolates are provided, based primarily on the rDNA internal transcribed spacers (ITS1-5.8S-ITS2) region and for representative isolates also on the small subunit 18S rDNA region and cytochrome c oxidase subunit 1 (cox-1) gene locus. Genetic data on worms recovered from Microtus spp. from the European mainland and from other rodent genera from the Palaearctic, North America and West Africa are also included. We test historical hypotheses indicating that S. nigeriana is a generalist species, infecting a range of different rodent genera. Our results establish that S. nigeriana is a parasite of both bank and field voles in the British Isles. An identical genotype was also recorded from Hubert's multimammate mouse (Mastomys huberti) from Senegal, but Mastomys spp. from West Africa were additionally parasitized by a related, although genetically distinct Syphacia species. We found no evidence for S. petrusewiczi in voles from the British Isles but isolates from Russia and North America were genetically distinct and formed their own separate deep branch in maximum likelihood molecular phylogenetic trees.

Two new genera and species of Nippostrongylinae (Nematoda: Heligmonellidae) parasites of two murine rodents (Muridae): from the Moluccas, Indonesia and Papua New Guinea with a comment on a pentastomatid.

Bisastrongylus multiovorum gen. nov., sp. nov. (Nematoda: Heligmonellidae: Nippostrongylinae) is described from a murid, Melomys obiensis, from the Moluccas, Indonesia. The new genus differs from all other Nippostrongylinae genera in having a synlophe of 12 unequal ridges with a type A carene, the dorsal ridge 1 being larger than the ventral ridge 1'. Pentastomid larvae, an acanthocephalan, Plagiorhynchus sp., and the nematodes Rictularia sp., a spirurid and the nippostrongylin Soricstrongylus obreensis gen. nov., sp. nov. were collected from the murid Pseudohydromys murinus from Central Province, Papua New Guinea. The new genus is distinguished by a combination of characters including a synlophe of 11-13 ridges at mid body, left ventral ridges larger and a sub frontal axis of orientation. The assemblage of P. murinus is discussed and a re-evaluation of nippostrongylin Odilia sp., previously reported from P. murinus indicates that the specimens were likely a Parasabanema sp.

Molecular characterisation and updated description of Neoechinorhynchus aldrichettae Edmonds, 1971 (Acanthocephala: Neoechinorhynchidae), based on material from Aldrichetta forsteri (Valenciennes) collected in Tasmania, Australia.

We report on Neoechinorhynchus aldrichettae Edmonds, 1971 (Acanthocephala: Neoechinorhynchidae), obtained from yellow-eye mullet Aldrichetta forsteri (Valenciennes) (Mugiliformes: Mugilidae) from the Huon River, Tasmania, Australia. We provide new 18S and 28S rDNA gene sequence data for N. aldrichettae, assess its phylogenetic position relative to other species of Neoechinorhynchus and provide an updated morphological account of this species including detail of features omitted in the type-description, specifically of the apical organ, a collar at the base of the neck and a para-receptacle structure associated with the proboscis receptacle. We determine that eggs in this species are ovoid, without polar prolongations of fertilisation membrane, which permits assignment of N. aldrichettae to the subgenus Neoechinorhynchus. Our phylogenetic analyses place N. (N.) aldrichettae in a clade with other species of Neoechinorhynchus which parasitise mullets in marine and estuarine waters. We find that, in terms of monophyletic clades, the current subgeneric classification system for Neoechinorhynchus is not reflected in our phylogenetic analyses.

Gorgorhynchoides pseudocarangis n. sp. (Acanthocephala: Isthmosacanthidae) from Pseudocaranx dentex (Carangidae) in southeast Queensland, Australia, with comments on the Isthmosacanthidae.

Gorgorhynchoides pseudocarangis n. sp. (Isthmosacanthidae), is described from the intestine of the white trevally Pseudocaranx dentex (Bloch & Schneider) (Carangiformes: Carangidae) collected in Moreton Bay, Queensland, Australia. The new species has a proboscis armature of 27-28 rows of 16-17 hooks. It is most similar morphologically to Gorgorhynchoides bullocki Cable & Marafachisi, 1970 and Gorgorhynchoides gnathanodontos Smales, 2014 but differs from the former in having a longer proboscis with more rows of hooks, ventral hooks 6/7-12 with notched tips and trunk spines which do not extend onto the anterior bulbous swelling, and from the latter in having a longer proboscis, ventral hooks 6/7-12 with notched tips, more circles of trunk spines, larger eggs and a proboscis armature with all hooks lacking manubria. Previous molecular phylogenetic analyses have shown that the genus Serrasentis Van Cleave, 1923 is sister to Gorgorhynchoides Cable & Linderoth, 1963, although some have failed to resolve these two lineages in separate monophyletic clades. We performed novel single-gene and concatenated phylogenetic analyses using cox1 mtDNA, 18S and 28S rDNA gene-sequences, resolving Gorgorhynchoides and Serrasentis in monophyletic sister clades and demonstrating that Gorgorhynchoides pseudocarangis n. sp. is phylogenetically distinct from related species for which molecular sequence data are available. We view the previous amendment of the Isthmosacanthidae to include the genera Golvanorhynchus Noronha, Fabio & Pinto, 1987, Gorgorhynchoides, Isthmosacanthus Smales 2014 and Serrasentis, and the transfer of the family to the Polymorphida, as the most satisfactory classification at present, although additional molecular evidence would provide greater stability.

Proposal of Spinulacorpus biforme (Smales, 2014) n. g., n. comb. and the Spinulacorpidae n. fam. to resolve paraphyly of the acanthocephalan family Rhadinorhynchidae Lühe, 1912.

Previous phylogenetic analyses of the Acanthocephala have demonstrated that the families Rhadinorhynchidae Lühe, 1912 and Transvenidae Pichelin & Cribb, 2001 are sister clades. However, a recent study found that the Rhadinorhynchidae is paraphyletic, due to the basal position of Rhadinorhynchus biformis Smales, 2014 relative to the Rhadinorhynchidae + Transvenidae. We reassess these relationships with new single-gene and concatenated phylogenetic analyses utilising cox1 mtDNA, 18S rDNA and 28S rDNA, including recently available sequences. Although topologies differed among single-gene analyses, the overall results support R. biformis as representative of a lineage distinct from those of the Rhadinorhynchidae and Transvenidae. Examination of additional specimens of R. biformis allowed us to identify morphological characters that further support this hypothesis. These results lead us to propose transfer of R. biformis to a new genus (Spinulacorpus n. g.) and family (Spinulacorpidae n. fam.) to resolve the paraphyly of the Rhadinorhynchidae.

Correction to: Molecular characterisation of acanthocephalans from Australian marine teleosts: proposal of a new family, synonymy of another and transfer of taxa between orders.

Shortly after publication it was brought to authors' attention that two of the cox1 sequences reported in the study, those of Neoechinorhynchus tylosuri (MN692675) and Transvena annulospinosa (MN692690) were potentially erroneous. After investigation, it was determined that this was indeed the case and was caused by contamination of original sequencing results. They were found to be near-duplicates of other species from the same sequencing batch. These sequences have been removed from GenBank. Unfortunately, this means that no cox1 sequence data were provided for the above two species in the referenced study. The remaining cox1 sequences reported have been checked and are reliable. Furthermore, cox1 sequence data were not analysed as part of the study, and thus the above error does not affect the results or conclusions of the study. Corrections to the text in reference to the above are made in Table 1 (removal of the above GenBank accession numbers), on page 10 ("Sequence data for all three targeted markers were obtained for 13 (rather than 15) of the 17 acanthocephalan species studied") and on page 19 ("We generated new cox1 sequence data for all but three (rather than one) of the acanthocephalan species from our collection…").

Molecular characterisation of acanthocephalans from Australian marine teleosts: proposal of a new family, synonymy of another and transfer of taxa between orders.

We provide molecular data (cox1, 18S rDNA and 28S rDNA) for 17 acanthocephalan species and 20 host-parasite combinations from Australian marine teleosts collected from off Queensland, Australia. Fourteen of these acanthocephalans are characterised with molecular data for the first time and we provide the first molecular data for a species of each of the genera Heterosentis Van Cleave, 1931, Pyriproboscis Amin, Abdullah & Mhaisen, 2003 and Sclerocollum Schmidt & Paperna, 1978. Using 18S and 28S rDNA sequences, the phylogenetic position of each newly sequenced species is assessed with both single-gene and concatenated 18S+28S maximum likelihood and Bayesian inference analyses. Additional phylogenetic analyses focusing on the genus Rhadinorhynchus Lühe, 1912 and related lineages are included. Our phylogenetic results are broadly consistent with previous analyses, recovering previously identified inconsistencies but also providing new insights and necessitating taxonomic action. We do not find sufficient evidence to recognise the Gymnorhadinorhynchidae Braicovich, Lanfranchi, Farber, Marvaldi, Luque & Timi, 2014 as distinct from the Rhadinorhynchidae Lühe, 1912. The family Gymnorhadinorhynchidae and its sole genus, Gymnorhadinorhynchus Braicovich, Lanfranchi, Farber, Marvaldi, Luque & Timi, 2014, are here recognised as junior synonyms of Rhadinorhynchidae and Rhadinorhynchus, respectively. The two species currently assigned to Gymnorhadinorhynchus are recombined as Rhadinorhynchus decapteri (Braicovich, Lanfranchi, Farber, Marvaldi, Luque & Timi, 2014) n. comb. and Rhadinorhynchus mariserpentis (Steinauer, Garcia-Vedrenne, Weinstein & Kuris, 2019) n. comb. In all of our analyses, Rhadinorhynchus biformis Smales, 2014 is found basal to the Rhadinorhynchidae + Transvenidae Pichelin & Cribb, 2001, thus resulting in a paraphyletic Rhadinorhynchidae. It appears that R. biformis may require a new genus and family; however, morphological data for this species are currently insufficient to adequately distinguish it from related lineages, thus we defer the proposal of any new higher-rank names for this species. Species of the genus Sclerocollum, currently assigned to the Cavisomidae Meyer, 1932, are found nested within the family Transvenidae. We transfer the genus Sclerocollum to the Transvenidae and amend the diagnosis of the family accordingly. The genera Gorgorhynchoides Cable & Linderoth, 1963 and Serrasentis Van Cleave, 1923, currently assigned to the Rhadinorhynchidae, are supported as sister taxa and form a clade in the Polymorphida. We transfer these genera and Golvanorhynchus Noronha, Fabio & Pinto, 1978 to an emended concept of the Isthomosacanthidae Smales, 2012 and transfer this family to the Polymorphida. Lastly, Pyriproboscis heronensis (Pichelin, 1997) Amin, Abdullah & Mhaisen, 2003, currently assigned to the Pomphorhynchidae Yamaguti, 1939, falls under the Polymorphida in our analyses with some support for a sister relationship with the Centrorhynchidae Van Cleave, 1916. As this species clearly does not belong in the Pomphorhynchidae and is morphologically and molecularly distinct from the lineages of the Polymorphida, we propose the Pyriprobosicidae n. fam. to accommodate it.

Morphological and molecular characterisation of a new genus and species of acanthocephalan, Tenuisoma tarapungi n. g., n. sp. (Acanthocephala: Polymorphidae) infecting red-billed gulls in New Zealand, with a key to the genera of the Polymorphidae Meyer, 1931.

Acanthocephalans of the family Polymorphidae Meyer, 1931 are cosmopolitan parasites that infect the intestines of fish-eating birds and mammals. Polymorphid acanthocephalans recovered from the intestines of red-billed gulls (Chroicocephalus scopulinus (Forster)) from the Otago coast, New Zealand, although morphologically similar to the genus Arhythmorhynchus Lühe, 1911 nevertheless have a unique molecular profile showing considerable genetic differentation, and are here diagnosed and described as Tenuisoma tarapungi n. g., n. sp. Characters which distinguish T. tarapungi include a very elongate, cylindrical hindtrunk, swollen anterior trunk with a spinose region, a secondary swelling in males only containing the testes, and hypodermal nuclei distributed throughout the length of the trunk. Molecular data (cox1, 18S, 28S) confirm that the representative of the new genus is closest to, but nonetheless strongly divergent from species of Pseudocorynosoma Aznar, Pérez-Ponce de León & Raga, 2006. Immature specimens are described and illustrated, demonstrating the extreme degree of hindtrunk inversion occurring in immature individuals of this species. We provide a key to the genera of the family Polymorphidae.

Acanthocephalans from Australian elasmobranchs (Chondrichthyes) with a description of a new species in the genus Gorgorhynchus Chandler, 1934 (Rhadinorhynchidae).

Gorgorhynchus occultus n. sp. is described from Sutorectus tentaculatus (Peters) (Orectolobidae) collected off Bunbury, Western Australia in 1986. The new species differs from all other species of Gorgorhynchus Chandler, 1934 by having a suite of characters including a proboscis hook formula of 18-20 rows of 8-9 hooks, a well-developed neck, irregular circles of small spines in a single anterior field, the male reproductive system limited to the posterior quarter of the trunk and three cement glands. In a survey of 284 sharks collected between 2015 and 2018 from 10 localities in Australian waters, 11 individuals were infected with acanthocephalan cystacanths. One individual of Sphyrna mokarran (Rupell) (Sphyrnidae) was infected with Corynosoma cetaceum Johnston & Best, 1931. Serrasentis sagittifer (Linton, 1889) (Rhadinorhynchidae) was found in five individuals of S. mokarran, four individuals of Syphyrna lewini (Griffith & Smith) and one individual of Carcharhinus coatesi (Whitley) (Carcharhinidae). These infections may be accidental because it has been suggested that acanthocephalans cannot tolerate the high levels of urea used by marine and esturine elasmobranchs for osmoregulation. The two most common host species examined, S. mokarran and S. lewini had the highest intensities and prevalences of infection with S. sagittifer. Although more individuals of S. lewini were examined, S. mokarran had the higher prevalence of infection.

Morphological and molecular evidence for synonymy of Corynosoma obtuscens Lincicome, 1943 with Corynosoma australe Johnston, 1937 (Acanthocephala: Polymorphidae).

Corynosoma obtuscens Lincicome, 1943 (Acanthocephala: Polymorphidae) is synonymised with Corynosoma australe Johnston, 1937 based on combined morphological and molecular evidence. Morphological comparison of C. obtuscens (24 males and 27 females) collected from a California sea lion Zalophus californianus (Lesson) in California, USA, with the type-specimens of C. obtuscens and C. australe, and with published data on C. australe collected from different hosts and regions showed no significant differences. The levels of genetic divergence in the cox1 sequences obtained from C. obtuscens from a California sea lion in the present study and C. australe from otariid seals from Argentina and penguins from Brazil ranged between 1.4-1.6% and was considered to represent intraspecific variability. Additionally, cox1 sequences were generated for Andracantha phalacrocoracis (Yamaguti, 1939), Corynosoma semerme (Forssell, 1904), C. strumosum (Rudolphi, 1802), C. validum Van Cleave, 1953 and C. villosum Van Cleave, 1953. Our results revealed inconsistency in the identification of material used as a source of the previously published sequence data for C. obtuscens and C. magdaleni Montreuil, 1958.

Parasitic nematodes of the genus Syphacia Seurat, 1916 infecting Muridae in the British Isles, and the peculiar case of Syphacia frederici.

Syphacia stroma (von Linstow, 1884) Morgan, 1932 and Syphacia frederici Roman, 1945 are oxyurid nematodes that parasitize two murid rodents, Apodemus sylvaticus and Apodemus flavicollis, on the European mainland. Only S. stroma has been recorded previously in Apodemus spp. from the British Isles. Despite the paucity of earlier reports, we identified S. frederici in four disparate British sites, two in Nottinghamshire, one each in Berkshire and Anglesey, Wales. Identification was based on their site in the host (caecum and not small intestine), on key morphological criteria that differentiate this species from S. stroma (in particular the tail of female worms) and by sequencing two genetic loci (cytochrome C oxidase 1 gene and a section of ribosomal DNA). Sequences derived from both genetic loci of putative British S. frederici isolates formed a tight clade with sequences from continental worms known to be S. frederici, clearly distinguishing these isolates from S. stroma which formed a tight clade of its own, distinct from clades representative of Syphacia obvelata from Mus and S. muris from Rattus. The data in this paper therefore constitute the first record of S. frederici from British wood mice, and confirm the status of this species as distinct from both S. obvelata and S. stroma.

Redescription of Maupasina weissi (Seurat, 1913) (Nematoda: Ascaridida) from sengis, Elephantulus spp. and Macroscelides proboscideus (Shaw) (Macroscelidea), in Africa.

Maupasina weissi (Seurat, 1913), is redescribed from the eastern rock sengi, Elephantulus myurus Thomas & Schwann, from Limpopo Province and compared with material collected from Free State and North West Provinces, South Africa, as well as the description of the type-material from South Tunisia. Distinguishing features of the species include a corona radiata of 12 pointed leaflike elements, a complex bipartite buccal capsule with 3 large bicuspid denticular lobes and 4 smaller club-shaped lobes and 11 (occasionally 10) pairs of cloacal papillae in the male. The complex taxonomic history of the genus Maupasina Seurat, 1917 is discussed. The probable misidentification of Macroscelides proboscideus Shaw, the short eared sengi, from North West Province, South Africa, as a host of M. weissi is explained, indicating that M. weissi occurs only in species of the genus Elephantulus Thomas & Schwann. The widely separated geographical regions, stretching the length of the African continent, in which M. weissi has been found are indicative of a conservative species with a broad geographical distribution. Tenebrionid beetles, up to 50% of stomach contents of E. myurus in Limpopo Province may act as intermediate hosts in the life-cycle of M. weissi.

A new species of Centrorhynchus Lühe, 1911 (Acanthocephala: Centrorhynchidae) from the lizard buzzard Kaupifalco monogrammicus (Temminck) (Aves: Accipitridae) in South Africa.

Centrorhynchus sarehae n. sp. is described from the lizard buzzard Kaupifalco monogrammicus (Temminik) in Louis Trichardt City, Limpopo Province, South Africa. The new species can be distinguished from all other species of Centrorhynchus Lühe, 1911 except C. gendrei (Golvan, 1957) and C. mariauxi Smales, 2011 in having a dilated region in the posterior trunk of the female. Centrorhynchus sarehae differs from both these species in the characters of the proboscis armature, particularly the number of hooks per row and the lengths of the longest hooks. This is the first record of a fully identified species of Centrorhynchus in South Africa.

A review of the genus Sclerocollum Schmidt & Paperna, 1978 (Acanthocephala: Cavisomidae) from rabbitfishes (Siganidae) in the Indian and Pacific Oceans.

Seven of the eleven species of Siganus Richardson (Siganidae) collected off the coasts of Australia, New Caledonia, French Polynesia and Palau were infected with species of Sclerocollum Schmidt & Paperna, 1978 (Acanthocephala: Cavisomidae). A Principal Component Analysis (PCA) and a Discriminant Analysis were performed on a morphometric dataset of specimens of Sclerocollum including borrowed type-specimens of Sc. rubrimaris Schmidt & Paperna, 1978 from the Indian Ocean and of Sc. robustum Edmonds, 1964, the only acanthocephalan species known previously from an Australian siganid. These analyses showed that the lengths of proboscis hooks were useful variables for separating specimens into groups and supported the presence of two known species (Sc. robustum and Sc. rubrimaris) and one new species (Sc. australis n. sp.) in Australian waters. We found Sc. robustum in Siganus lineatus (Valenciennes) from off Queensland and Sc. rubrimaris in S. fuscescens (Houttuyn) from off Western Australia and Queensland, S. punctatissimus Fowler & Bean from off Queensland and S. argenteus (Quoy & Gaimard), S. corallinus (Valenciennes), S. canaliculatus (Park) and S. doliatus Guérin-Méneville from off New Caledonia (all new host and locality records) which we compared with museum specimens of Sc. rubrimaris from S. rivulatus Forsskål & Niebuhr and S. argenteus [as S. rostratus (Valenciennes)] from the Red Sea. The third species, Sclerocollum australis n. sp., was found only in S. corallinus and S. doliatus from off Queensland. Sclerocollum australis n. sp. can be distinguished from its congeners by a unique combination of characters of the proboscis armature, including lengths of hooks 1-7. Specimens of Sclerocollum were also found in Zebrasoma velifer (Bloch) (Acanthuridae) from off Queensland, and Coradion altivelis McCulloch (Chaetodontidae) and Heniochus acuminatus (Linnaeus) (Chaetodontidae) from off New Caledonia. No acanthocephalans were found in siganids collected from Palau (Micronesia) or Moorea (French Polynesia) or Moreton Bay and Noosa (Queensland, Australia). We found no acanthocephalans in S. puellus (Schlegel), S. punctatus (Schneider & Forster), S. spinus (Linnaeus) or S. vulpinus (Schlegel & Müller). Evidence suggests that species of the genus Sclerocollum have travelled with S. argenteus across the Indo-Pacific with Sc. rubrimaris dispersed widely and Sc. robustum and Sc. australis n. sp. restricted to the Queensland coast, Australia.

Population dynamics of two diplectanid species (Monogenea) parasitising sparid hosts (Sparidae).

Economically important sparid fish species, gilthead (Sparus aurata) and white seabream (Diplodus sargus) (Sparidae) are frequently parasitised by diplectanid monogeneans, known to induce severe losses in farming conditions. We have analysed population dynamic of two diplectanid species, Lamellodiscus echeneis and Lamellodiscus ignoratus (Monogenea: Diplectanidae) collected from two bream species in the Beymelek Lagoon (southwest coast of Turkey), comparing it between different host variables (fish size, age and sex) in order to have insight in parasites' ecology, important for managing parasitosis in the intensive aquaculture system. In seabream (N = 127), L. echeneis prevalence was 46.5 % (exact 95 % confidence limits 38.90-54.14), mean abundance 5.64 (bootstrap 95 % confidence limits 4.20-7.65) and mean intensity 12.14 (bootstrap 95 % confidence limits 9.49-15.59). In white seabream (N = 102), L. ignoratus prevalence was 24.5 % (exact 95 % confidence limits 16.53-34.03), mean abundance 1.73 (bootstrap 95 % confidence limits 0.98-3.21) and mean intensity 7.04 (bootstrap 95 % confidence limits 4.60-11.40). Parasites' parameters differed only between seasons in both hosts and between age categories in gilthead, but not in white seabream.

Nematodes of Heligmonellidae (Strongylida) of Pogonomys championi Flannery and Pogonomys sylvestris Thomas (Rodentia: Muridae) from Papua New Guinea with descriptions of five new species.

Eight species of heligmonellid nematodes including five new species and a putative new species were identified from the digestive tracts of 12 Pogonomys championi Flannery and 27 P. sylvestris Thomas (Murinae: Hydromyini) from Papua Indonesia. Hasanuddinia pogonomyos Smales, 2014 had been previously described from P. loriae Thomas and P. macrourus (Milne-Edwards) and Odilia mackerrasae (Mawson, 1961) from several endemic rodent species. Bunomystrongylus ilami n. sp. can be distinguished from its congeners by the number of rounded ridges in the synlophe; Hasanuddinia hasegawai n. sp. by the number of ridges, three ventral being hypertrophied, in the synlophe; Montistrongylus kaindiensis n. sp. by the number of ridges in the synlophe and the length of the spicules; Odilia helgeni n. sp. in the characters of the synlophe ridges; Odilia whittingtoni n. sp. in the characters of the synlophe ridges and the length of the spicules. Species richness of the nematode assemblage of P. sylvestris, nine species and a juvenile heligmonellid, was comparable to those of P. loriae and P. macrourus but that of P. championi, five species, was considered depauperate. Species composition showed both commonalities between the host species as well as distinctive features. Three of five species in the assemblage were unique to P. championi and five of nine species to P. sylvestris.

An annotated checklist of Acanthocephala from Australian fish.

Thirty one genera, comprising 58 named species, 15 undetermined species and nine species known only as cystacanths from paratenic fish hosts were found infesting 144 marine, esturine and freshwater species of fish from Australian and Australian Antarctic waters. Host habitats are given and the distribution and records of the acanthocephalans are given. A key to these parasites at the generic level is provided.

Two New Species of the Genus Heterakis (Heterakidae) from the Genera Echymipera, Isoodon and Perameles (Peramelidae), Bandicoots from Papua New Guinea and Australia.

PURPOSE: To identify and describe any new nematode species of the genus Heterakis Dujardin, 1845 (Heterakidae Railliet & Henry, 1914) found in bandicoots (Peramelidae Gray, 1825) collected from Australia and Papua New Guinea and held in the South Australian Museum, Adelaide. METHODS: All the relevant specimens registered in the South Australian Museum were examined as temporary wet mounts, after clearing in lactophenol, using an Olympus BH-2 microscope with differential interference optics. Measurements were made with an eyepiece micrometer and figures drawn using a drawing tube. RESULTS: Heterakis balamukensis n. sp. was described from Echymipera kabulu (Lesson, 1828) collected from Balamuk station, Bensbach River, Papua New Guinea and Heterakis oweni n. sp. was described from Isoodon macrourus (Gould, 1842) collected from Papua New Guinea, and Queensland, Australia. Heterakis sp. females were identified from I. macrourus from the Northern Territory and Perameles pallescens Thomas, 1923 from Queensland, Australia. A key to the valid species of Heterakis from mammals is given. CONCLUSIONS: The heterakid fauna of mammals now comprises eight species: the cosmopolitan species Heterakis spumosa Schneider, 1886 as well as H. balamukensis n. sp., H. fieldingi Smales, 1996, H. oweni n. sp. and H. sirawii Smales, 2016 from Australasia, H. dahomensis (Gendre, 1911) from Africa, and H. inglisi Gupta & Trevadi, 1982 and H. yamagutii Gupta & Trevadi, 1982 from India. Two species have been declared species inquirenda; H. equispicularis Uphadyyay, 2017 and H. verrucosa Molin, 1860, while H. rattui Ghambir, Gyaneswori, Tarnita, Indrani & Zenith, 2008 falls as a junior synonym of H. spumosa. No infections of the cosmopolitan species infecting rodent hosts, Heterakis spumosa Schneider, 1866, were found in bandicoots.

Pomphorhynchidae and quadrigyridae (Acanthocephala), including a new genus and species (Pallisentinae), from freshwater fishes, Cobitidae and Cyprinodontidae, in Turkey.

During a survey of freshwater fishes from Turkey two species of Acanthocephala, one of them new, were found. Pomphorhynchus tereticollis (Pomphorhynchidae) is reported at 24% prevalence in 37 Cobitis bilseli (Cobitidae) from Lake Beysehir, Konya, for the first time. The eoacanthoacaphalan Triaspiron aphanii gen. n. et sp. n. (Quadrigyridae), at a prevalence of 90%, is described from 29 Aphanius mento (Cyprinodontidae), from Kirkgöz Springs, Antalya. The new genus most closely resembles Raosentis Datta, 1947, both having a small spindle shaped trunk, and Acanthogyrus Thapar, 1927, both having a proboscis armature of three circles of hooks. Triaspiron differs from Raosentis in proboscis shape, cylindrical not globular, proboscis armature, three circles, a total of 16 hooks in all, not four circles, a total of 26-30 hooks in all, and trunk spination, two fields of spines in the anterior field with spines arranged in up to 40 circular rows, not a single field with 9-17 rows of spines. Triaspiron differs from Acanthogyrus in having fewer proboscis hooks, 16 compared with 18-24, arranged in three circles, one anterior and two posteriorly placed, with an unarmed region between, not three circles of hooks evenly spaced, and two fields of trunk spines, not one.

A new acanthocephalan family, the Isthmosacanthidae (Acanthocephala: Echinorhynchida), with the description of Isthmosacanthus fitzroyensis n. g., n. sp. from threadfin fishes (Polynemidae) of northern Australia.

Isthmosacanthus fitzroyensis n. g., n. sp. is described from two species of protandrous fish, Eleutheronema tetradactylum (Shaw) and Polydactylus macrochir (Günther), from the waters around the coast of northern Australian. The new species can be distinguished from all others by the following combination of characters: proboscis shape and armature (22 rows of 13-14 hooks), short neck, trunk spined anteriorly and having two swellings (one bulbous) with a narrow isthmus in between, long tubular lemnisci and six tubular cement glands. Although I. fitzroyensis has been confused with a species of Pomphorhynchus Monticelli, 1905 in the literature, it can be distinguished from all pomphorhynchids, including species of Longicollum Yamaguti, 1935 and Pyriproboscis Amin, Abdullah & Mhaisen, 2003, by the suite of characters listed above. The placement of the species of Pyriproboscis in the Pomphorhynchidae Yamaguti, 1939 is problematical, because it has a short neck, two distinct hook types comprising the proboscis armature and only two rather than six cement glands. A new family, the Isthmosacanthidae n. fam., is erected to contain Isthmosacanthus together with Gorgorhynchoides Cable & Linderoth, 1963 and Golvanorhynchus Noronha, Fabio & Pinto, 1978, genera having an elongate to clavate proboscis, anterior trunk spines, elongate lemnisci, and six tubular cement glands. The validity of this determination, based on the importance of cement gland number and phylogenetic analysis, is argued.