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The molecular profile of Pararhadinorhynchus magnus Ha, Amin, Ngo, Heckmann, 2018 described from Scatophagus argus (Linn.) off Haiphong in the Gulf of Tonkin, Pacific Ocean, Vietnam is provided for the first time. It was morphologically distinguished from the South Australian species, Pararhadinorhynchus mugilis Johnston and Edmonds, 1947 and Pararhadinorhynchus coorongensis Edmonds, 1973 from mullets. Two other species of Pararhadinorhynchus are also recognized: Pararhadinorhynchus upenei Wang, Wang, Wu, 1993 from China and Pararhadinorhynchus sodwanensis Lisitsyna, Kudlai, Cribb and Smit, 2019 from South Africa. The assignment of Diplosentis manteri Gupta and Fatma, 1980 to Pararhadinorhynchus is not recognized. Sequences of the 18S, small internal transcribed spacers (ITS1-5.8S-ITS2) and 28S from nuclear DNA were generated to molecularly characterize P. magnus. The phylogenetic analyses were achieved by comparison of the 18S and ITS1-5.8S-ITS2 region only as the 28S amplified a short region (425–428 bp) that was not sufficient for the present study. Phylogenetic analyses showed that P. magnus and the other species of Pararhadinorhynchus sequenced were nested within separate clades in the case of 18S gene and suggesting that these species do not share a common ancestor. In contrast, the ITS1-5.8S-ITS2 region shows a close arrangement of species of Pararhadinorhynchus with molecular affinities to the family Diplosentidae, suggesting that final placement of these species in Transvenidae needs further study and revision. The molecular data from the present study will provide further comparative insights into species of Pararhadinorhynchus and its close affiliation to other acanthocephalan species and genera from different geographical areas.

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 Luhe, 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 Luhe, 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.

Rhadinorhynchus trachuri Harada, 1935 is probably one of the most widely distributed acanthocephalans in the world, but the least known taxonomically. This report fills the large gap of knowledge about its taxonomy, host relationships, and worldwide distribution in marine fishes of both sides of the Pacific Ocean and the connecting Indian Ocean. To revisit the taxonomy of this species, provide a more complete morphological description and expand our knowledge about its morphological identity and variations and elaborate on its worldwide zoogeography; accounting for its worldwide distribution based on new collections, museum specimens, and on published reports. Specimens from Vietnam were processed, identified, and documented using standard techniques. Specimens of R. trachuri were studied from three species of fish in three families, Auxis thazard (Lacepede) (Scombridae), Megalaspis cordyla (Linn.) (Carangidae), and Tylosurus sp. (Belonidae) in Nha Trang and Binh Thuan in the south Pacific coast of Vietnam and additional museum specimens mostly from salmonids from the Pacific coast of California were also studied. Extensive research was conducted on published records of R. trachuri and its marine fish hosts worldwide. Specimens of R. trachuri are characterized by cylindrical trunk with anterior rings of spines and posterior ventral and lateral spines, a proboscis usually with 12 hook rows each with 19–24 hooks, variable position of testes, and a long uterus, uterine bell attached to the dorsal trunk wall, rounded vagina, and unusually dorsal gonopore. The hosts and geographical distribution of R. trachuri suggest a northern linkage of infections between the Asian and American Pacific populations across the Bering Sea involving salmonid fishes and a southern linkage through the Indian Ocean involving Carangid fishes. Other hosts involved in the cycling and distribution of infections are also discussed with some definitive hosts also serving as paratenic hosts. This is the first complete description about R. trachuri and the first comprehensive accounting of its worldwide distribution in 19 species of marine fish in seven families. Considerable intraspecific variability related to geographical restrictions, intermediate and definitive host specificity and distribution, and host feeding behavior was documented.

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.

Of the 43 valid species of Rhadinorhynchus Luhe, 1911, 20 species are now known from the Pacific Ocean off Australia, Japan, and Vietnam. We have already described over 50 species and higher taxa from the Pacific Ocean off Vietnam over the last 15 years. The present research is a continuation of our efforts to taxonomically map new acanthocephalan taxa, especially from Vietnam. Some of our collections in 2016 and 2017 revealed the presence of new species of the genus Rhadinorhynchus from various species of marine fish off the Pacific coast of Vietnam. We provide descriptions of these new species here. Standard methods of collection and examination of marine hosts, processing and illustrating of specimens, and taxonomic identification of parasites using the extensive collections of the lead author were used. Type specimens were deposited at the Harold W. Manter Lab. collection, Lincoln, Nebraska. Three species Rhadinorhynchus are described from marine fish off the Vietnamese coast. Rhadinorhynchus circumspinus n. sp. with fusiform trunk, 1 field of anterior trunk spines, and anteriorly globular proboscis with up to 21 dorsoventrally differentiated hooks in 17–18 rows is described from Triacanthus biaculeatus Bloch (Triacanthidae) off Hai Phong. Rhadinorhynchus pacificus n. sp. with cylidrical trunk and proboscis with up to 25 dorso-ventrally similar hooks in 14–18 rows and trunk spines in 2 fields of dorsal, ventral and lateral spines is described from Auxis thazard (Lacepede) and Auxis rochei (Lacepede) (Scombridae) off Nha Trang. Rhadinorhynchus multispinosus n. sp. with cylindrical trunk and proboscis with up to 32 dorso-ventrally differentiated hooks in 12 rows, and many trunk spines in 2 fields of dorsal, ventral and lateral spines is described from Decapterus maruadsi (Temminck and Schlegel) (Carangidae) also off Hai Phong. Rhadinorhynchus polynemi Smales, 2014 of Australia is not the Indian species (with smallest basal hooks) as the basal hooks are largest and is now named Rhadinorhynchus australis nom. nov. (=Rhadinorhynchus polynemi Smales, 2014). Rhadinorhynchus trivandricus George and Nadakal, 1978 with smallest basal hooks and 8 pyriform cement glands is relegated to genus Indorhynchus Golvan, 1969. With the description of these 3 new species, the numner of valid species of Rhadinorhynchus has now increased to 46. We include a new generic diagnosis to accommodate the increased knowledge of variability within this genus.

Two rhadinorhynchid acanthocephalans are described from marine fishes off the Pacific coast of Vietnam. Sclerocollum neorubrimaris n. sp. (Gorgorhynchinae Van Cleave & Lincicome, 1940) is described from the spine-foot rabbitfish Siganus guttatus (Bloch) (Siganidae) off Nha Trang. The new species is similar to the type-species, Sclerocollum rubrimaris Schmidt & Paperna, 1978 in most measurements and counts but has a posterior cephalic ganglion, a sub-ventral female gonopore, and one dorsal paravaginal filament bundle. In S. rubrimaris, the cephalic ganglion is near the middle of the receptacle, the female gonopore is terminal with two paravaginal filament bundles. The new species is distinguished from three other species of Sclerocollum Schmidt & Paperna, 1978 in proboscis hook formulas and the position of the female gonopore and cephalic ganglion. The issue of the importance of the position of the cephalic ganglion at the generic and sub-generic levels in the Acanthocephala is discussed. Females of Australorhynchus multispinosus n. sp. (Gorgorhynchinae) are described from the red cornetfish Fistularia petimba Lacepede off Nha Trang in the Pacific south. It is distinguished from the only other species of the genus, Australorhynchus tetramorphacanthus Lebedev, 1967, by having more trunk spines extending beyond the level of the proboscis receptacle and a smaller proboscis with considerably fewer hooks.

Of the 46 known species of Rhadinorhynchus Luhe, 1911, only 6 species, including Rhadinorhynchus dorsoventrospinosus Amin, Heckmann, and Ha, 2011, have dorsal and ventral, as well as lateral, trunk spines in the posterior field of trunk spines. The other 5 species are Rhadinorhynchus erumei Gupta and Fatima, 1981, Rhadinorhynchus adenati (Golvan and Houin, 1964) Golvan, 1969, Rhadinorhynchus lintoni Cable and Linderoth, 1963, Rhadinorhynchus pacificus Amin, Rubtsova, and Ha, 2019, and Rhadinorhynchus multispinosus Amin, Rubtsova, and Ha, 2019. These 5 species are distinguished from R. dorsoventrospinosus by differences in proboscis hook armature, trunk spine organization, and egg size. The distinction of R. dorsoventrospinosus is further demonstrated by its molecular description. We amplified the 18S and ITS1+5.8S+ITS2 rDNA region and cytochrome c oxidase subunit 1 (COI) gene for this study. Unfortunately, no ITS1+5.8S+ITS2 gene sequences are available for comparison with other species of the genus Rhadinorhynchus. Therefore, phylogenetic trees generated from sequences of the 18S nuclear region and COI gene were analyzed for the phylogenetic position of isolates of R. dorsoventrospinosus. Rhadinorhynchus dorsoventrospinosus has been validated as a species based on comparisons of morphological (original description) and molecular features (this paper). The additional genetic data will be useful as more species are described and as more genetic material becomes available to improve taxon sampling in the genetic analysis.

Previous phylogenetic analyses of the Acanthocephala have demonstrated that the families Rhadinorhynchidae Luhe, 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.

Twenty-one species of acanthocephalans, representative of thirteen genera from ten families of seven orders and three classes, are included in this updated checklist of acanthocephalans in South Africa.Although South Africa appears to have a less diverse acanthocephalan fauna compared to some other countries such as Iran in Asia, or Brazil in South America, this is probably an artefact of fewer parasitological surveys.

Rhadinorhynchidae gen. sp. Actinopterygii Merluccius hubbsi Marini (Gadiformes, Merlucciidae). SI: intestine. SD: adult. L: Buenos Aires Province: Argentine-Uruguayan Common Fishing Zone. R: Sardella and Timi (1996). Note. Sardella and Timi (1996) identified these acanthocephalans as Gorgorhynchidae gen. sp., Published as part of Hern��ndez-Orts, Jes��s S., Kuchta, Roman, Semenas, Liliana, Crespo, Enrique A., Gonz��lez, Ra��l A. & Aznar, Francisco J., 2019, An annotated list of the Acanthocephala from Argentina, pp. 1-64 in Zootaxa 4663 (1) on page 21, DOI: 10.11646/zootaxa.4663.1.1, http://zenodo.org/record/3772372, {"references":["Sardella, N. H. & Timi, J. T. (1996) Parasite communities of Merluccius hubbsi from the Argentinian-Uruguayan common fishing zone. Fisheries Research, 27 (1 - 3), 81 - 88. https: // doi. org / 10.1016 / 0165 - 7836 (95) 00460 - 2"]}

A detailed list of acanthocephalans from Argentina was generated based on 205 published records. The list includes 52 named and 35 undetermined species of Acanthocephala infecting 6 species of invertebrate (2 amphipods, 3 decapods and 1 insect) and 155 species of vertebrate (one cartilaginous fish, 95 bony fishes, 10 amphibians, 3 reptiles, 13 birds and 33 mammals) host species in the Argentinean territory. The present list contains information on the invertebrate and vertebrate host(s), site of infection, developmental stage and locality(ies) of the acanthocephalans listed and references. For some species of acanthocephalans, information about repositories of the type material, voucher specimens, and DNA sequences of individual taxa are also presented. Finally, a host-Acanthocephala list is also provided. The data compiled revealed considerable gaps in the knowledge of the diversity, taxonomy, distribution, and life cycles of the acanthocephalans from Argentina. Fil: Hernández-Orts, Jesús S.. Universidad Nacional del Comahue. Centro de Investigación Aplicada y Transferencia Tecnológica en Recursos Marinos "Almirante Storni". - Provincia de Río Negro. Ministerio de Agricultura, Ganadería y Pesca. Centro de Investigación Aplicada y Transferencia Tecnológica en Recursos Marinos "Almirante Storni". Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet Centro Nacional Patagónico. Centro de Investigación Aplicada y Transferencia Tecnológica en Recursos Marinos "Almirante Storni"; Argentina Fil: Kuchta, Roman. Biology Centre Of The Academy Of Sciences Of The Czech Republic. Institute Of Parasitology. Laboratory Of Fish Protistology; República Checa Fil: Semenas, Liliana. Lab de Parasitologã­a-inibioma (conicet); Argentina Fil: Crespo, Enrique Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico. Centro para el Estudio de Sistemas Marinos; Argentina Fil: González, Raul Alberto Candido. Universidad Nacional del Comahue; Argentina Fil: Aznar, Francisco J.. Universidad de Valencia; España

The mitogenome of Brentisentisyangtzensis is 13,864 bp in length and has the circular structure typical of metazoans. It contains 36 genes: 22 transfer RNA genes (tRNAs), two ribosomal RNA genes (rRNAs) and 12 protein-encoding genes (PCGs). All genes are transcribed from the same strand. Thirteen overlapping regions were found in the mitochondrial genome. The overall A+T content of B.yangtzensis is 68.3% versus 31.7% of G+C content (A = 27.8%, T = 40.5%, C = 9.0%, G = 22.7%). B.yangtzenensis (Illiosentidae) and Leptorhynchoidesthecatus (Rhadinorhynchidae) form a sister clade, showing the relatively close relationship between the Illiosentidae and the Rhadinorhynchidae. The mitochondrial gene arrangements of acanthocephalan species are relatively conserved, with only a few translocations of tRNAs (trnS1, trnS2, trnV, and trnK) detected. An identical gene order was found both in a sister clade (Centrorhynchusaluconis and Plagiorhynchustransversus) and across different classes (B.yangtzensis (Palaeacanthocephala), Acanthosentischeni (Eoacanthocephala) and Macracanthorhynchushirudinaceus (Archiacanthocephala), Oncicolaluehei and L.thecatus (Palaeacanthocephala)). More studies and more sequences of acanthocephalan species are needed to gain a clear understanding of the phylogenetic relationships.

Rhadinorhynchus laterospinosus Amin, Heckmann & Ha, 2011 (Rhadinorhynchidae) was described from a single female collected from a trigger fish, Balistes sp. (Balistidae) from the northern Pacific coast of Vietnam in Halong Bay, Gulf of Tonkin. More recent collections of fishes in 2016 and 2017 revealed wider host and geographical distributions. We report this Acanthocephala from nine species of fish representing six families (including the original record from Balistes sp.) along the whole Pacific coast of Vietnam. The fish species are Alectis ciliaris (Carangidae), Auxis rochei (Scombridae), Auxis thazard (Scombridae), Leiognathus equulus (Leiognathidae), Lutjanus bitaeniatus (Lutjanidae), Megalaspis cordyla (Carangidae), Nuchequula flavaxilla (Leiognathidae), and Tylosurus sp. (Belonidae). We provide a complete description of males and females of R. laterospinosus, discuss its hook metal microanalysis using EDAX, and its micropores. Specimens of this species characteristically have lateral trunk spines bridging the anterior ring of spines with posterior field of ventral spines and a proboscis with 15–19 longitudinal alternating rows of 21–26 hooks each varying with host species. We demonstrate the effect of host species on the distribution and size of the trunk, proboscis, proboscis hooks, trunk spines, and reproductive structures. The molecular profile of this acanthocephalan, based on 18S rDNA and cox1 genes, groups with other Rhadinorhynchus species and further seems to confirm the paraphyly of the genus, which is discussed.

The genus Megistacantha Golvan, 1960 was originally described as monotypic with Megistacantha horridum (Lühe, 1912) from a mormyrid fish in Africa as its type- and only species. This species was described from one female specimen, but no description of the male was provided. In this study, the male of M. horridum is described for the first time. In addition, a new species, Megistacantha sanghaensis n. sp., is described from the Cornish jack Mormyrops anguilloides L., a mormyrid fish from the River Sangha, Dzanga-Sangha Protected Areas, Central African Republic. The diagnosis of Megistacantha Golvan, 1960 is amended and a key to its two species is provided.

The present study represents the first molecular–chemical screening by pyrolysis-field ionization mass spectrometry applied on fish parasites. A total of 71 fishes from Balinese fish markets, 36 Auxis rochei (Risso, 1810) and 35 A. thazard (Lacepede, 1800), were studied for their acanthocephalan parasites. This is the first record of Rhadinorhynchus zhukovi in Balinese waters, Indonesia, and we describe for the first time A. rochei and A. thazard as R. zhukovi hosts. Using this method, small scale variations within the chemical compounds of acanthocephalans could be detected. Using this methodology it will be possible to generate additional, pollutant specific information from aquatic habitats in future with the potential of a new bioindicator application for parasite/host origin and/or environmental pollution.

Specimens described as Rhadinorhynchus niloticus Meyer, 1932 (Rhadinorhynchidae) from two male specimens collected from Heterotis niloticus (Cuvier) in the Egyptian Nile were later redescribed in the genus Tenuisentis Van Cleave, 1936 (Tenuisentidae) based on 12 specimens collected from the same host species in the White Nile. That redescription basically distinguished the two genera based on five traits but did not actually provide a formal description. His account left out information about cerebral ganglion, lemnisci, some reproductive structures, eggs, proboscis hook dissymmetry and roots, size of trunk and a few other structures. We provide (i) the first complete description of this species enhanced by SEM, molecular, and histo-pathological studies; (ii) expand the existing descriptions; (iii) correct questionable accounts advanced by Van Cleave on the cement gland and the hypodermal giant nuclei; and (iv) add descriptions of new features such as the para-receptacle structure which we also report from Paratenuisentis Bullock & Samuel, 1975, the only other genus in Tenuisentidae Van Cleave, 1936. The subsequent description of a few more specimens from the same host collected in Mali was more informative yet incomplete and at variance with our specimens from Burkina Faso. Genetic divergence and phylogenetic analyses of mitochondrial (cytochrome oxidase c subunit I; COI) and nuclear (18S ribosomal RNA) gene relationships uncovered a cryptic species complex containing two lineages. Based on our studies, the family diagnosis is emended. The acanthocephalan causes damage to the host intestine as depicted in histopathological sections. The invading worm can extend from the mucosal layer to the muscularis externa of the host with subsequent tissue necrosis, villi compression, haemorrhaging and blood loss.

Amin, Omar M., Heckmann, Richard A., Dallarés, Sara, Constenla, María, Ha, Nguyen Van (2020): Morphological And Molecular Description Of Rhadinorhynchus Hiansi Soota And Bhattacharya, 1981 (Acanthocephala: Rhadinorhynchidae) From Marine Fish Off The Pacific Coast Of Vietnam. Journal of Parasitology 106 (1): 56-70, DOI: 10.1645/19-97, URL: http://dx.doi.org/10.1645/19-97

Seven species of acanthocephalans were identified for the first time in teleost fish from the Bizerte lagoon, Tunisia, includingNeoechinorhynchus(Hebesoma)agilis(Rudolphi, 1819) Van Cleave, 1916;N.(Neoechinorhynchus)rutiliMüller, 1780 (Neoechinorhynchidae);Acanthocephaloide propinquus(Dujardin, 1845) Meyer, 1932;A. incrassatus(Molin, 1858) Meyer, 1932 (Arhythmacanthidae);Longicollum pagrosomiYamaguti, 1935 (Pomphorhynchidae);Rhadinorhynchus cadenati(Golvan et Houin, 1964) Golvan, 1969 (Rhadinorhynchidae); andTelosentis exiguus(von Linstow, 1901) Van Cleave, 1923 (Illiosentidae).Acanthocephaloide propinquus,N.(N.)rutili,L. pagrosomiandR. cadenatiwere restricted to the rectum and the posterior intestine, whereas the other species (A. incrassatus,T. exiguusandN.(H.)agilis) colonized two or three parts of the intestine. The most diverse acanthocephalan fauna was recorded inLithognathus mormyrus, with three species; two species were reported fromTrachurus trachurus; and a single species was recorded inLiza aurataand inAtherina boyeri.Neoechinorhynchus(N.)rutili,L. pagrosomiandR. cadenatiattained the lowest prevalences of less than 6% and were considered as to be rare species.Acanthocephaloide incrassatus,A. propinquus,T. exiguusandN.(H.)agiliswere satellite species. The diversity of the acanthocephalan fauna in the fish from the Bizerte lagoon is compared with previous studies from other localities. The report ofA. incrassatus,A. propinquusandN.(N.)rutiliinL. mormyruspresents new host records in Mediterranean waters.

The use of parasites as biological tags for discriminating stocks of blue jack mackerel, Trachurus picturatus (Osteichthyes, Carangidae), in the northeast Atlantic Ocean is assessed herein. In this study the following parasites have been selected as possible biological tags: Anisakis spp. (Nematoda: Anisakidae), Rhadinorhynchus sp. (Acanthocephala: Rhadinorhynchidae), Nybelinia sp. (Cestoda: Tentaculariidae) and Bolbosoma sp. (Acanthocephala: Polymorphidae). Anisakis spp. was the most prevalent parasite taxon found in all localities, attaining higher values in fish from Peniche, mainland Portugal. The occurrence of Rhadinorhynchus sp. in fish from all studied areas was rare (prevalence

Specimens of a new species of Rhadinorhynchus Luhe, 1911 are described from the chub mackerel Scomber japonicus (Scombridae) and the Chilean Jack mackerel Trachurus murphyi (Carangidae) (possibly a subspecies of Trachurus symmetricus ) from the Pacific Ocean off the Peruvian coast at the Port of Chicama, La Libertad. Specimens of Rhadinorhynchus oligospinosus n. sp. are somewhat small having 11–14 rows of alternating proboscis hooks with 20–22 hooks each with posteriormost hooks in a continuous ring. Ventral hooks are robust with prominent roots but dorsal hooks are slender and shorter with discoid roots. Trunk spines are in two zones separated by a non-spiny region. Anterior trunk spines are in 2–3 complete circles but posterior spines are only ventral and lateral, and do not extend posterior to the level of the posterior end of the proboscis receptacle in both sexes. The new species is closest to Rhadinorhynchus seriolae (Yamaguti, 1963) Golvan, 1969 found in Japanese and Australian waters, but not as close to 19 other species found in the same Pacific waters off Australia, Japan, and Vietnam. In R. seriolae , posterior trunk spines extend well past the receptacle in females, among other diagnostic differences. Proboscis hooks of the new species were analyzed for chemical elements using X-ray in conjunction with EDAX (energy-dispersive analysis for X-ray) software; sulfur had a higher concentration at the edge than the middle of cut hooks.

Seventy specimens of the gilthead sea bream Sparus aurata of the Red Sea were collected during the period from March to November 2013; they were dissected and examined for parasitic acanthocephalans. Only 40 (57.14 %) specimens were found to be naturally infected with Serrasentis sagittifer belonging to family Rhadinorhynchidae. The infection was recorded in the intestine, pyloric ceca, and the external surfaces of some internal organs of the infected fish. Seasonally, the prevalence of infection was increased to 77.14 % during summer season and decreased to 37.14 % during winter. Light and scanning electron microscopic investigation revealed that the adult worm was elongated (with broad anterior and narrow posterior ends) and measured 6.9–8.6 (7.6 ± 0.2) × 0.57–0.73 (0.63 ± 0.02) mm for male and 10.2–12.1 (11.5 ± 0.2) × 0.71–0.82 (0.76 ± 0.02) mm for female. Proboscis was long and cylindrical with a length of 0.97–1.6 mm (1.2 ± 0.2) for male and 1.12–1.17 mm (1.14 ± 0.02) for female. It was covered with numerous uniform spines arranged longitudinally as 9–11 rows each equipped by 15–18 spines. Spines were triangular, arrow-shaped, strong, and covered with cuticular theca; they decreased in size from the apex to the base of the proboscis. The proboscis is followed by a short spineless neck region followed by the body proper which is supported by multiple combs of spines (16–20) on its ventral surface. Molecular analysis of 18S rDNA sequence for the parasite demonstrated a close identity (>83 %) between the present acanthocephalan and other previously described species within class Palaeacanthocephala with 98 % identity with the previously recorded S. sagittifer (acc. no. JX014227) which is supported by the morphological data and the presence of trunk spines arranged within rows (comb-like) and the presence of four cement glands in the males. So, according to the records of morphological and molecular analyses, the present parasite is classified as S. sagittifer belonging to class Palaeacanthocephala and family Rhadinorhynchidae with a new host record from the gilthead sea bream S. aurata of the Red Sea.

Micracanthorhynchina hemirhamphi (Baylis, 1944) is reported from Western Australia for the first time. New hosts, including the definitive hosts Pomatomus saltatrix (Linnaeus, 1776) from New South ...

Acanthocephalan parasites, Serrasentis sagittifer, from a shark, Carcharhinus sorrah, and a species of Pararhadinorhynchus from a ray, Himantura granulata, are reported from Queensland, Australia. The collection of acanthocephalans from cartilaginous fish (elasmobranchs) as either occasional or definitive hosts is unusual, but not unknown. In this instance, the finding of S. sagittifer is considered an occasional infection. The life cycle of Pararhadinorhynchus sp., 1 of 4 species known only from elasmobranch hosts, is equivocal, as putative bony fish hosts are unknown. Of the other 3 species, only Megapriapus ungriai has an elasmobranch acknowledged as the definitive host.

Of the three known species of Leptorhynchoides Kostylew 1924, two are reported from North American fishes: Leptorhynchoides aphredoderi Buckner and Buckner 1976 and Leptorhynchoides thecatus (Linton 1891) Kostylew 1924. The third species, Leptorhynchoides plagicephalus (Westrumb 1821) Kostylew 1924, is commonly found in the Caspian and Black Sea from at least four species of sturgeons including Acipenser stellatus Pallas 1771 and the Acipenser nudiventris Lovetzsky 1828 from which Leptorhynchoides polycristatus n. sp. was found. No taxonomic work has been reported for L. plagicephalus for the last 90 years. L. polycristatus n. sp. can be readily confused with L. plagicephalus because of many superficial similarities. Such similarities include the general shape of the trunk, proboscis, and organ systems. However, L. polycristatus is clearly distinguished from the other three species primarily by having (1) 19-20 proboscis hooks per row; (2) the shortest hooks are anterior and the longest at the middle; the opposite is true in L. plagicephalus; (3) with a cuticular collar enveloping the base of the proboscis hooks; (4) the surface of its proboscis hooks is ribbed; (5) with a broad collar of multiple rectangular cuticular crests encircling the anterior end of the trunk; this is the only member of Leptorhynchoides with such a structure; (6) with many large ovoid uninucleated cells in the subcuticular layer of the trunk; (7) with paired glandular clusters near the male reproductive opening and of suction cup-like sensory structures on the bursa; (8) with dorsoventral ligament across the vagina; (9) cement glands are in a cluster of eight arranged in two horizontal tiers of four glands each; (10) with female gonopore near terminal; (11) with structures interpreted as possible microtriches on the surface of the trunk; (12) and with thinner eggs. L. polycristatus caused extensive histopathological damage to host intestinal layers. The armed proboscis invades and attaches to the host mucosa causing villi compression and necrosis of the epithelial lining with subsequent hemorrhaging and granulocyte migration. No encapsulation of the acanthocephalan is visible, and the worm can migrate deep into the smooth muscle layers of the muscularis extrema. The presence of L. polycristatus in the lumen of the host intestine obstructs and damages the absorbing surface of the host affecting the nutritional potential. Dead, necrotic host epithelial tissue and remnants of villi and crypts are visible.

Adult and cystacanth forms of the acanthocephalan Serrasentis sagittifer from Australian coastal waters are redescribed and verified as the same species using both molecular and morphological data. This study provides the baseline 18S rDNA, 28S rDNA, and cox1 sequence data to serve as genetic barcode for S. sagittifer. The validity of the currently recognized species of Serrasentis is discussed. The most recently described species are junior synonyms of either Serrasentis nadakali or S. sagittifer, and a number of species are species inquirenda. When using morphological characters to distinguish the species of Serrasentis, consideration needs to be given to the maturity of the specimens, since the trunk elongates and the number and distribution of the ventral combs changes as worms mature, although the proboscis armature itself does not change. A simple key to assist in the identification of species of Serrasentis is provided. Adult S. sagittifer appear to be highly host specific to the cobia, Rachycentron canadum, in northern Australian waters, whereas cystacanths have been reported from a wide range of fish species. The relationship between host length and number of cystacanths shows that most paratenic infections are acquired as young fish, most likely via a crustacean intermediate host.

Males of Cathayacanthus spinitruncatus Amin, Heckmann & Ha, 2014 (Rhadinorhynchinae Lühe, 1912) are described for the first time from Leiognathus equulus in Hai Phong and Nha Trang and from pony fish Nuchequula flavaxilla in Quang Ninh in the Pacific waters of Vietnam. The male allotype status is designated. Males of C. spinitruncatus are smaller and have fewer and smaller proboscis hooks and trunk spines than females. The male reproductive structures are in the posterior fifth of the trunk and with 6 club-shaped cement glands gradually merging into 6 independent cement gland ducts. The proboscis receptacle is more than half as long as the trunk and with a cephalic ganglion at its anterior end. In females, the receptacle is only about one fifth the length of the trunk. Specimens described as Cathayacanthus bagarii Moravec & Sey, 1989 were shown to have been wrongly assigned to Cathayacanthus. Pararhadinorhynchus magnus n. sp. (Diplosentidae) is described from Scatophagus argus off Hai Phong in the Gulf of Tonkin. It is the third species of the genus and is readily distinguished from the Australian species by having a considerably larger trunk and male reproductive structures, and more proboscis hooks. X-ray microanalysis (EDAX) of intact and gallium-cut hooks of P. magnus showed high calcium and phosphate mainly in the central core. Specimens of Heterosentis holospinus Amin, Heckmann & Ha, 2011 (Arhythmacanthidae) are also reported from L. equulus off Quang Binh, new host and locality records.

Adults of Rhadinorhynchus ornatus Van Cleave, 1918 were collected from the small intestine of skipjack tuna, Katsuwonus pelamis (Linnaeus), in the high seas of the Pacific Ocean off the west coast of South America (new parasite locality record) and described using optical microscopy and a scanning electron microscope (SEM). Our specimens were somewhat comparable to those described from North America and Japan, but had more trunk spines. Definitive differences between the length and thickness of each of the dorsal and ventral proboscis hooks are noted for the first time, with most ventral middle hooks being relatively shorter and more robust than dorsal middle hooks. The SEM documented, for the first time, the different surface topography of the tegument in the proboscis, the neck, and in 3 trunk regions; the presence of microtrichs in the mid- and posterior trunk regions; the elevated base of trunk spines; the circular arrangement of basal proboscis hooks; the different morphology of all dorsal and ventral proboscis hooks and the striations of their surface; the ribbed surface topography of eggs; the elevated slit-like female gonopore; and the rimmed edge of the bursa. The presence of microtrichs on the tegumental surface is further supported by transmission electron microscopy studies. This is the first report of microtrichs in any species of Acanthocephala and the second report of striations in proboscis hooks. The geographical distribution of R. ornatus appears to correspond, at least in part, to that of its epipelagic primary host, K. pelamis, throughout the world in waters ranging in temperature from 14.7 to 30 C.

A study of Gorgorhynchoides bullocki in 1,319 fish, including members of 37 species, from Bahia de Chetumal and the associated lagoonal system of Rio Huach, Quintana Roo, Mexico, was initiated in order to investigate the finding of cystacanths in Eucinostomus jonesii (Perciformes: Gerreidae; slender mojarra) and Atherinomorus stipes (Atheriniformes: Atherinidae; hardhead silverside). In total, 563 fish, 254 E. jonesii and 309 A. stipes, were collected from the Laguna Rio Huach system; cystacanths of G. bullocki were found to infect individuals of both species, but they were more prevalent in E. jonesii (mean abundance = 2.48; intensity = 1–27 worms) than A. stipes (mean abundance = 0.34; intensity = 1–14). A Kolmogorov–Smirnov test of similarity of distribution of helminths in the 2 populations of fishes indicated that the 2 distributions differed significantly (p < 0.0001). For E. jonesii, there was a significant difference in the mean abundance of cystacanths in relation to the month in which t...

The systematic relationships of acanthocephalans, including Leptorhynchoides and Pseudoleptorhynchoides that occur in freshwater and marine fishes in Neartic and Neotropical regions, are enigmatic. Leptorhynchoides (3 species) and Pseudoleptorhynchoides (1 species) are presently classified in the Rhadinorhynchidae. However, recent molecular and morphological phylogenies have challenged the monophyly of this family. Sequences of nuclear ribosomal DNA (large subunit, small subunit regions) and the mitochondrial cytochrome c oxidase subunit I gene of Leptorhynchoides thecatus and Pseudoleptorhynchoides lamothei were used in phylogenetic analyses with available sequences of 26 other acanthocephalans. Maximum parsimony and maximum likelihood analyses were identical in placing both genera in the Illiosentidae. Bootstrap analyses also indicate that placement of these genera with members of Illiosentidae is reliably supported.

Serrasentis sp. Host: Epi. coioides Locality: Persian Gulf (Peyghan et al. 2004) Host: L. malabaricus Locality: Persian Gulf (Peyghan et al. 2004) Host: Otolithus ruber Locality: Persian Gulf (Peyghan et al. 2004) Host: Parastromateus niger Locality: Persian Gulf (Peyghan et al. 2004) Host: Pomadasys kaakan Locality: Persian Gulf (Peyghan et al. 2004) Host: Stromateus cinereus Locality: Persian Gulf (Peyghan et al. 2004), Published as part of Tavakol, Sareh, Amin, Omar M., Luus-Powell, Wilmien J. & Halajian, Ali, 2015, The acanthocephalan fauna of Iran, a check list, pp. 237-258 in Zootaxa 4033 (2) on page 245, DOI: 10.11646/zootaxa.4033.2.3, http://zenodo.org/record/233772, {"references":["Peyghan, R., Hoghoghi-Rad, N. & Yousef-Desfuli, A. (2004) Determination of parasitic helminthes in Persian gulf grouper (Epinephelus coioides) and Silver pomfret (Stromateus cinereus). Journal of Pajouhesh-va-Sazandegi, 62, 49 - 55."]}

Serrasentis sagittifer (Linton, 1889) Van Cleave, 1923 Host: Bothus sp. Locality: Persian Gulf (Amin et al. 1984) Host: Coryphaena hippurus Locality: Oman Sea (Alinezhad & Hoseini 1998) Host: Epinephelus tavina Locality: Persian Gulf (Radfar 1998) Host: Lutjanus coccineous Locality: Persian Gulf (Amin et al. 1984) Host: L. fulviflammus Locality: Persian Gulf (Amin et al. 1984) Host: Nemipterus japonicus Locality: Persian Gulf (Amin et al. 1984; Ghaem-maghami et al. 2008) Host: Nem. tolu Locality: Persian Gulf (Amin et al. 1984) Host: Otolithus argenteus Locality: Persian Gulf (Amin et al. 1984), Published as part of Tavakol, Sareh, Amin, Omar M., Luus-Powell, Wilmien J. & Halajian, Ali, 2015, The acanthocephalan fauna of Iran, a check list, pp. 237-258 in Zootaxa 4033 (2) on pages 244-245, DOI: 10.11646/zootaxa.4033.2.3, http://zenodo.org/record/233772, {"references":["Linton, E. (1889) Notes on Entozoa of Marine Fishes of New England with Descriptions of Several New Species. Report of the U. S. Commisioner of Fish and Fisheries for 1886, Part 14, 453 - 498.","Van Cleave, H. J. (1923) Telosentis, a new genus of Acanthocephala from southern Europe. Journal of Parasitology, 9, 174 - 175. http: // dx. doi. org / 10.2307 / 3271095","Amin, O. M., Nahhas, F. M., Al-Yamani, F. & Abu-Hakima, R. (1984) On Three Acanthocephalan Species from Some Arabian Gulf Fishes Off the Coast of Kuwait. Journal of Parasitology, 70 (1), 168 - 170. http: // dx. doi. org / 10.2307 / 3281951","Alinejad, S. & Hoseini, S. H. (1998) Helminths infection in Dolphin fish (Coryphaena hippurus) in off shore of Oman Sea. Journal of Faculty of Veterinary Medicine, University of Tehran, 53 (3,4), 43 - 46.","Radfar, M. H. (1998) Helminth parasites of Greasy grouper (Epinephelus tavina) in Persian Gulf. Doctor of Philosophy dissertation, University of Tehran, Tehran, 213 pp."]}

Sclerocollum rubrimaris Schmidt and Paperna, 1978 Host: Siganus oramin Locality: Persian Gulf (Amin et al. 1984), Published as part of Tavakol, Sareh, Amin, Omar M., Luus-Powell, Wilmien J. & Halajian, Ali, 2015, The acanthocephalan fauna of Iran, a check list, pp. 237-258 in Zootaxa 4033 (2) on page 244, DOI: 10.11646/zootaxa.4033.2.3, http://zenodo.org/record/233772, {"references":["Schmidt, G. D. & Paperna, I. (1978) Sclerocollum rubrimaris gen. et sp. n. (Rhadinorhynchidae: Gorgorhynchinae), and other Acanthocephala of marine fishes from Israel. Journal of Parasitology, 64, 846 - 850. http: // dx. doi. org / 10.2307 / 3279515","Amin, O. M., Nahhas, F. M., Al-Yamani, F. & Abu-Hakima, R. (1984) On Three Acanthocephalan Species from Some Arabian Gulf Fishes Off the Coast of Kuwait. Journal of Parasitology, 70 (1), 168 - 170. http: // dx. doi. org / 10.2307 / 3281951"]}

Leptorhynchoides plagicephalus (Westrumb, 1821) Kostylew, 1924 Host: Aci. gueldenstaedtii Locality (reference): Caspian Sea (Hajimoradlou & Ghorbani 2003; Sattari & Mokhayer 2005 a) Host: Aci. nudiventris Locality (reference): Caspian Sea (Sattari & Mokhayer 2005 a) Host: Aci. persicus Locality: Caspian Sea (Ghoroughi 1994; Sattari et al. 2000 a; Hajimoradlou & Ghorbani 2003; Sattari & Mokhayer 2005 b; Ebrahimi & Malek 2007; Masoumzadeh et al. 2007; Haghparast et al. 2007; Rajabpour et al. 2008) Host: Aci. stellatus Locality: Caspian Sea (Asgharzadeh & Hajimoradlou 2002; Sattari et al. 2000 b; Sattari & Mokhayer 2005 b; Ebrahimi & Malek 2007; Rajabpour et al. 2008) Host: Huso huso Locality: Caspian Sea (Ghoroughi 1994), Published as part of Tavakol, Sareh, Amin, Omar M., Luus-Powell, Wilmien J. & Halajian, Ali, 2015, The acanthocephalan fauna of Iran, a check list, pp. 237-258 in Zootaxa 4033 (2) on page 244, DOI: 10.11646/zootaxa.4033.2.3, http://zenodo.org/record/233772, {"references":["Westrumb, A. H. L. (1821) De helminthibus acanthocephalis. Commentatio historico-anatomica adnexo recensu animalium, in Museo Vindobonensi circa helminthes dissectorum et singularum specie rum harum in illis repertarum. Helwig, Hanoverae, 85 pp.","Kostylew, N. N. (1924) Le genre Leptorhynchoides, nouveau genre d'acanthocephale parasite des poisons. Annales de Parasitologie Humaine et Comparee, 2, 214 - 223.","Sattari, M. & Mokhayer, B. (2005 a) Occurrence and Intensity of some parasitic Worms in Acipenser gueldenstaedti, A. nudiventris and Huso huso (Chondrostei: Acipenseridae) from the southwest of Caspian Sea. Turkish Journal of Veterinary Animal Science, 29, 1279 - 1284.","Ghoroughi, A. (1994) Study on parasites of Huso huso in southern parts of Caspian Sea. Project's report of Fisheries Research Organization, Mazandaran Province, 150 pp.","Sattari, M., Mokhayer, B. & Bokaei, S. (2000 a) Parasites of Acipenser persicus (Chondrostei: Acipenseridae) from south-west of Caspian Sea. Journal of Veterinary Medicine Faculty of Tehran University, 55 (3), 19 - 24.","Sattari, M. & Mokhayer, B. (2005 b) Occurrence and intensity of some parasites in five sturgeon species (Chondrostei: Acipenseridae) southwest of Caspian Sea. Current Science, 89 (2), 259 - 263.","Ebrahimi, M. & Malek, M. (2007) Study of helminth parasites of Acipenser persicus and Acipenser stellatus (Chondrostei: Acipenseridae) from the southern coast of Caspian Sea. Journal of Science, University of Tehran, 33 (4), 75 - 82.","Haghparast, S., Moghaddam, A., Hajimorad-Loo, A., Pahlavani, M. H., Amini, K., Taheri, A. & Mohammad-Khani, A. (2007) The prevalence of helminth parasites of digestive tract of Persian sturgeon broodstocks (Acipenser persicus) in the southeast of the Caspian Sea. Iranian Journal of Fisheries Sciences, 16 (3), 1 - 10.","Rajabpour, M., Malek, M., Mackenzie, K. & Aghlmandi, F. (2008) Helminth parasites of Stellate sturgeon Acipenser stellatus Pallas, 1771 and Persian sturgeon Acipenser persicus Borodin, 1897 (Pisces: Acipenseridae) from the South-East Caspian Sea. Parasitology Research, 102 (5), 1089 - 1091. http: // dx. doi. org / 10.1007 / s 00436 - 008 - 0922 - 7","Asgharzadeh-Kafi, A. & Hajimoradlou, A. (2002) Study on helminth parasites of Acipenser stellatus in southern part of Caspian Sea. In: Proceeding of the Second National Conference of Sturgeons. The International Sturgeon Research Institute, Rasht, pp. 71 - 74.","Sattari, M., Mokhayer, B. & Hashemi-Nasab, M. F. (2000 b) Parasites of Acipenser stellatus (Chondrostei: Acipenseridae) from south-west of Caspian Sea. Journal of Pajouhesh-va-Sazandegi, 49, 92 - 98."]}

Serrasentis sagittifer is one of the most important acanthocephalan parasites parasitizing fish. This species attach to the intestinal wall via their armed proboscis which is anchored by rows of recurved spines. In the present study, Twenty two out of 50 fish specimens (44.0%) were found to be naturally infected by adult worms of Serrasentis Sagittifer Linton, 1889 (Acanthocephala: Rhadinorhynchidae) which were collected from the stomach and intestine of the common sea bream Pagrus pagrus (family: Sparidae) from locations along the Red Sea at Hurghada City, Egypt. The light and scanning microscopic study revealed that the adult worm possessed a proboscis which was long, cylindrical with a uniform width measured 0.81 ± 0.020 (0.77-0.84) mm in length and 0.48 ± 0.020 (0.33-0.69) mm in width. Claviform, armed with 25 (23-28) longitudinal rows of hooks which show a distinct dorsoventral asymmetry, with ventral hooks stouter, larger. Proboscis receptacle was 2.12 ± 0.30 (2.10-2.14) long, double-walled, with ganglion at mid-level; two unequal, long and thin lemnisci 2.9 ± 0.30(2.41-3.33) length, arised from the base of the neck, and extend up to the med-level of the trunk. The present species is compared morphologically and morphometrically with some of the previously recorded species isolated from different host species, which revealed that the present species should be classified as Serrasentis sagittifer with a new host record in Egypt.

Laboratory-reared cystacanths of Leptorhynchoides thecatus (Acanthocephala: Rhadinorhynchidae) were used to study the effect of cystacanth size on adult success and the factors that influence cystacanth size within the intermediate host. To assess how host size and intensity of infection influence cystacanth size, infected amphipods (Hyalella azteca) were measured, and sex, length, and width of cystacanths were determined. After a subset of cystacanths was measured, small- and large-size classes of cystacanths were designated. To determine how cystacanth size relates to adult size, green sunfish (Lepomis cyanellus) were fed 10 large or small cystacanths. Fish were dissected 6 wk after infection, and worms were removed. After adult worms were permanently mounted on slides, their length and width were measured. Intensity of infection and amphipod size significantly influenced cystacanth size in that large amphipods harbored larger cystacanths than did small amphipods and heavy infections produced smaller cystacanths than did light infections. Adult worms from the small and large cystacanth-size classes showed no significant difference in size; however, large cystacanths had a significantly higher establishment and survival than did small cystacanths: 40% of large worms and 14% of small worms were recovered. The results of this study indicate that host size and host sharing influence cystacanth size and that cystacanth size is an important factor in determining adult success.

Gymnorhadinorhynchus gen. n. is proposed to accommodate its type species, G. decapteri sp. n., a parasite of the marine fish Decapterus punctatus (Cuvier), caught from the coastal waters of Brazil. Gymnorhadinorhynchus decapteri sp. n. was morphologically most similar to species of two echinorhynchid families, the Rhadinorhynchidae and the Cavisomidae, particularly in the structure of the proboscis and the absence of somatic spines, respectively. This combination of morphological features made it difficult to assign our specimen to an extant family of the Acanthocephala. Therefore, in order to clarify the systematic placement of G. decapteri, a molecular phylogenetic analysis was performed based on the SSU and LSU rDNA and the mitochondrial cox1 gene sequences obtained for the new taxon and other 26 acanthocephalan species. The results of parsimony and maximum likelihood analyses, using individual, combined and concatenated sequence data, consistently indicate that the specimens do not belong to any known family of the Echinorhynchida. Rather, G. decapteri represents a distinct lineage that is closely related to the Transvenidae, but distantly related to both the Rhadinorhynchidae and the Cavisomidae. Gymnorhadinorhynchidae fam. n. is therefore erected. This newly described family can be distinguished from other families of Echinorhynchida by the combination of the following morphological characters: a proboscis cylindrical with 10 rows of 22?26 hooks, dorsoventral differences in proboscis hooks, basal hooks forming a ring and being abruptly larger than anterior hooks, absence of trunk spines and presence of four tubular cement glands. This combination, in addition to several molecular autapomorphies, justifies the erection of a new genus, Gymnorhadinorhynchus gen. n., in order to accommodate this new species. Fil: Braicovich, Paola Elizabeth. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones Marinas y Costeras. Universidad Nacional de Mar del Plata. Facultad de Ciencia Exactas y Naturales. Instituto de Investigaciones Marinas y Costeras; Argentina Fil: Lanfranchi, Ana Laura. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones Marinas y Costeras. Universidad Nacional de Mar del Plata. Facultad de Ciencia Exactas y Naturales. Instituto de Investigaciones Marinas y Costeras; Argentina Fil: Farber, Marisa Diana. Instituto Nacional de Tecnología Agropecuaria; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Marvaldi, Adriana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto Argentino de Investigaciones de las Zonas Áridas. Provincia de Mendoza. Instituto Argentino de Investigaciones de las Zonas Áridas. Universidad Nacional de Cuyo. Instituto Argentino de Investigaciones de las Zonas Áridas; Argentina Fil: Luque, José L.. Universidade Federal Rural Do Rio de Janeiro; Brasil Fil: Timi, Juan Tomas. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones Marinas y Costeras. Universidad Nacional de Mar del Plata. Facultad de Ciencia Exactas y Naturales. Instituto de Investigaciones Marinas y Costeras; Argentina

The rhadinorhynchidSclerocollum saudiiAl-Jahdali, 2010 was found in the intestine of its type host,SiganusrivulatusForsskål & Niebuhr, 1775, a siganid fish permanently resident in a lagoon within the mangrove swamps found on the Egyptian coast of the Gulf of Aqaba (between 28°7′N and 28°18′N). Larval forms of this acanthocephalan (acanthors, acanthellae and cystacanths) were only found inMegaluropus agilisHoek, 1889 (Crustacea: Gammaridae), a benthic amphipod abundant on algae and seagrasses in the lagoon. So, this life cycle ofS. saudiiwas elucidated under semi-natural conditions: embryonated eggs ofS. saudiiwere directly ingested by the amphipod and hatched in its intestine; the released acanthor penetrated the intestinal epithelium in 12–18 h to reach the connective tissue serosa, where it remained for about 3 days, then penetrated the intestinal wall and remained attached to its outer surface for 4 days. It then detached and dropped free in the amphipod haemocoel and transformed into an oval acanthella, growing for 16 days to reach the cystacanth stage. The cystacanth at 46 days post-infection was infective to fish (excysted in its intestine as an active juvenile). Male and female juveniles reached maturity 17 and 23 days post-infection. Recently copulated females first appeared 26 days post-infection and all females seemed to be copulated at 28 days post-infection; partially and fully gravid females first appeared 31 and 35 days post-infection. Mature males and fully gravid females started to die off naturally 31 and 43 days post-infection and were totally expelled from the fish intestine by 42 and 52 days post-infection. The cycle was completed in 89 days and is similar to other known palaeacanthocephalan life cycles, but has its own characteristics.

Species of Rhadinorhynchus, collected from Australian waters were examined. Specimens of Rhadinorhynchus from Scorpis aequipinnis, Girella tricuspidata, Johnius australis and Grammatobothus polyophthalmus could not be identified further. New host and locality records are reported for R. bicircumspinus found in Trachurus declivis and Rexea solandri from the east coast of Tasmania; R. carangis found in Trachinotus bailonii and T. copperingi from Queensland and Western Australian coasts; R. polynemi from Queensland; R. seriolae found in Seriola lalandi from the east coast of Australia. An immature female specimen of R. johnstoni provided no additional data on the species. Rhadinorhynchus biformis sp. nov., described from Pelates quadrilineatus and a trumpeter from Moreton Bay, Queensland differs from all its congeners in the pattern of the trunk spines, a single field of numerous small spines ventro-laterally, overlapping with irregular rows and circles of larger spines extending posteriorly. Rhadinorhynchus pichelinae sp. nov. described from Upeneichthys vlamingi from Point Peron, Western Australia differs from all its congeners in having proboscis armature of 10 longitudinal rows of 24–28, usually 26–27 hooks up to 87 long and a single field of 21–24 irregular circles of spines on the anterior trunk, with the posterior circles incomplete dorsally. Rhadinorhynchus polydactyli sp. nov. described from Polydactylus sp. from Moreton Bay is differentiated from all congenerics by the elongated neck of the females and having a proboscis armature of up to 34 hooks in 10 longitudinal rows. Rhadinorhynchus pomatomi sp. nov. found in Pomotomus saltrix differs from its most similar congeners, those without dorsal trunk spines, in having a proboscis armature of 12–15 rows of 20–22 hooks up to 73.5–80.5 long. Rhadinorhynchus bicircumspinus, R. biformis, R. pichelinae, R. polydactyli and R. pomatomi are known only from Australian waters while R. carangis and R. seriolae are also known from Japanese waters, R. johnstoni from the western Pacific and R. polynemi from the Indian coast.

Adult worms of Rhadinorhynchus dorsoventrospinosus (Acanthocephala: Rhadinor-hynchidae) were collected from the small intestine of the red spot emperor Lethrinus lentjan (family Lethrinidae) from locations along the Red Sea at Jeddah City, Saudi Arabia. Twenty three out of 70 fish specimens (32.9%) were found to be naturally infected. The parasite was described using photo research Zeiss microscopy and a scanning electron microscope (SEM). Light microscopic studies revealed that the adult worm possessed a proboscis which was long, cylindrical with a uniform width measured 0.44 +/- 0.02 (0.38-0.46) mm in length and 0.1 +/- 10.02 (0.09-0.15) mm in width. Proboscis hooks observed by scanning electron microscopy were large, uniform in size (14-16 rows of 26 hooks each) with a row of longer hooks at the base. Comparison between the present described species and four species of the same genus was done, it was observed that there was only one comparable species, R dorsoventrospinosus resembled the present parasite in the general morphology and differed from others, so the present studied species is classified as R. dorsoventrospinosus with new host and locality records.

Two rhadinorhynchid species of acanthocephalans, Rhadinorhynchus dorsoventrospinosus sp. nov. and Rhadinorhynchus laterospinosus sp. nov. are described from the redtail scad, Decapterus kurroides Bleeker, and the trigger fish Balistes sp., respectively. The hosts were collected off Cat Ba Island, Halong Bay, Gulf of Tonkin, Vietnam in May, 2009. This brings the total number of species of Rhadinorhynchus Lühe, 1911 to 38. Specimens of the first species are characterized by having 11–12 proboscis hook rows with 30–31 hooks each, large dorsal and ventral spines in the posterior field of trunk spines, large eggs (100 × 20), and subterminal gonopore in both males and females. It is further characterized by many prominent fragmented nuclei in the body wall. The 1 female of the second species has 18 proboscis hook rows with 24 hooks each, smaller eggs (62 × 17), lateral trunk spines connecting those in the anterior and the posterior fields, and subterminal female gonopore. Notes on the genus Rhadinorhynchus, lists of the invalid and valid species, and a key to species are provided. Raorhynchus Tripathi, 1959 is proposed to be a junior synonym of Rhadinorhynchus pending a revision of the species of Raorhynchus.

The study of mitotic and meiotic chromosomes of Leptorhyncoides plagicephalus is reported. The karyotype (2n=7/8) is composed of 1 pair of metacentric, 1 pair of submetacentric 2 pairs of telocentric and a XO XY sex-determining mechanism.

Sclerocollum saudii sp. nov. (Fig. 2 A���H) Description. Based on 30 whole-mounts of each stage: Cystacanths (Fig. 2 A) Elongate, cylindrical, usually curved at one end, 1,125���3,512 (2,318) �� 300���659 (479), and contains a single active juvenile measuring 516���910 in length; Excystment of juvenile is through a tubular portion released from the cyst, and is preceded by squirts of a foamy material. Newly excysted juvenile (Fig. 2 B) Trunk 953���1,340 (1,164) in length, differentiated into an anterior frustum-shaped part (contains proboscis receptacle and lemnisci) and a posterior tubular part (contains anlagen of reproductive system). Frustumshaped part 491���855 (673) in length, 450���748 (599) in greatest width near its base. Tubular part 448���690 �� 195���221 (569 �� 208). Proboscis relatively short, cylindrical, 294���362 �� 82���130 (328 �� 106), armed with 10 alternating longitudinal rows of sharp recurved hooks; each row includes 8���9 hooks of variable length; basal hooks alternate with each other (not forming ring). Proboscis hooks: first 3 hooks, 27���32 (29); next 3, 29��� 35 (32); and the remaining 2 or 3, 21��� 25 (23) in length. Neck short, 41���63 (52) in length. Proboscis receptacle cylindrical, 290���394 �� 118���146 (342 �� 132). Lemnisci claviform, 372���468 �� 96���144 (420 �� 120). Anlagen of reproductive system hardly seen; sex of a newly excysted juvenile not evident. Immature worms (Fig. 2 C, D) Immature males (Fig. 2 C): Trunk elongate-fusiform, 2,311���5,370 (3,840) in length, 396���688 (542) in greatest width at its anterior region. Proboscis 308���364 �� 75���93 (336 �� 84). Proboscis hooks: first 3 hooks, 30���34 (32); next 3, 32��� 38 (35); and the remaining 2 or 3, 23��� 28 (25) in length. Neck 64���76 (70) in length. Proboscis receptacle 348���470 �� 78���102 (427 �� 90). Lemnisci 877���1,043 �� 73���111 (960 �� 92). Testes 2, elongate-oval, tandem, contiguous, nearly in middle of trunk; anterior testis 205���390 �� 98���196 (297 �� 147), posterior testis 210���412 �� 84���164 (311 �� 124). Cement glands 4, tubular, shriveled, in two tandem pairs; anterior pair 311���681 (496) in length; posterior pair 275���615 (445) in length. Seminal vesicle irregularly tubular, shriveled. Genital pore terminal. Immature females (Fig. 2 D): Trunk elongate, 2,910���6,013 (4,461) in length, 671���1,102 (886) in greatest width at level of lemnisci. Proboscis 355���376 �� 91���129 (365 �� 110). Proboscis hooks closely similar to those of males in size. Neck 65���81 (73) in length. Proboscis receptacle 378���602 �� 106���156 (490 �� 131). Lemnisci 811���1,060 �� 75���117 (935 �� 96). Uterine bell 113���153 �� 65���97 (133 �� 81), its base 534���1,128 (831) from posterior end. Uterus tubular, short, 417���765 (591) long. Vagina short, guarded by sphincter muscle on each side. Genital pore terminal. Mature worms (Fig. 2 E���H) General: Body moderate in size. Females larger than males. Trunk thick-walled, uspined; conspicuous sclerotised plaques embedded in the tegument at the anterior region of the trunk. Proboscis relatively short (Fig. 2 H), cylindrical, armed with 10 alternating longitudinal rows of sharp recurved hooks; each row includes 8���9 hooks of variable length; basal hooks alternate with each other (not forming ring). Neck short. Proboscis receptacle double-walled, relatively short, claviform. Ganglion near middle of proboscis receptacle. Lemnisci claviform, equal in length, distinctly longer than proboscis receptacle. Mature males (Fig. 2 E): Trunk elongate-fusiform, 5,624���11,350 (8,487) in length, 881���1,378 (1,129) in greatest width at its anterior region. Proboscis 323���387 �� 95���140 (355 �� 117). Proboscis hooks: first 3 hooks, 34���38 (36); next 3, 36��� 40 (38); and the remaining 2 or 3, 24��� 30 (27) in length. Neck 65���91 (78) in length. Proboscis receptacle 522���829 �� 124���176 (675 �� 150). Lemnisci 1,161���1,944 �� 98���178 (1,332 �� 138); lemnisci length/ Proboscis receptacle length is about 2.3. Testes 2, elongate-oval, tandem, contiguous, in middle of trunk or slightly anterior; anterior testis 513���875 �� 240���400 (694 �� 320); posterior testis 525���1,053 �� 209���425 (789 �� 317). Cement glands 4, tubular, in two tandem pairs; anterior pair 755���2,310 �� 90���205 (1,532 �� 147); posterior pair 690���1,960 �� 81���165 (1,325 �� 123). Seminal vesicle claviform, relatively large. Copulatory bursa well developed, hemispherical, 371���637 (504) in diameter. Genital pore terminal. In copulating male, the extrusion of the bursa appears to induce a slight displacement of the sexual organs toward the posterior end. Mature females (Fig. 2 F): Trunk elongate, 6,595���15,421 (11,008) in length, 695���1,421 (1,058) in greatest width at its anterior region. Proboscis 335���391 �� 90���138 (363 �� 114). Proboscis hooks closely similar to those of males in size. Neck 71���107 (89) in length. Proboscis receptacle 483���725 �� 121���185 (604 �� 153). Lemnisci 1,032���1,735 �� 91���157 (1,383 �� 124); lemnisci length/ Proboscis receptacle length is about 2.25. Uterine bell well developed, 166���198 �� 85���154 (182 �� 119), its base 1,480���3,081 (2,280) from posterior end. Selector apparatus 210���394 �� 65���113 (238 �� 89). Uterus tubular, relatively short, 1,357���2,841 (2,099) long. Vagina short, guarded by sphincter muscle. Genital pore terminal. Eggs elongate (Fig. 2 G), small, with polar swelling of middle membrane; uterine eggs 20���28 �� 6���10 (24 �� 8). Type host. Siganus rivulatus Forssk��l (Teleostei, Siganidae). Site. Anterior 80 % of intestine. Type locality. Red Sea off the coast of Rabigh, Saudi Arabia. Prevalence. 24 / 30 fishes examined; 80 %. Type material. Holotype and paratypes are deposited in the Natural History Museum, London, Reg. no. male-holotype-2009.11.13.6, female-allotype-2009.11.13.7, male and female paratypes-2009.11.13. 8���10. Etymology. The specific name saudii refers to the locality (Saudi Arabia). Remarks. As mentioned above, 2 species of Sclerocollum are currently recognized, i.e. S. rubrimaris Schmidt et Paprena, 1978 (type species) and S. robustus (Edmonds, 1964) Schmidt et Paprena, 1978. The first is the best known, since it has been recorded in many siganid species (Siganus argenteus, S. canaliculatus, S. luridus, S. oramin, S. rivulatus, S. rostratus and S. sutor) from the Red Sea, Arabian Gulf and Kenyan coast (see Amin et al. 1984; Diamant 1989, El-Naffar et al. 1992; Martens and Moens 1995; Geets and Ollevier 1996; Hassanine 2006; Hassanine and Al-Jahdali 2007), while the second is still known only from its original description. In both species, the proboscis is armed with 14 alternating longitudinal rows of sharp hooks; in the former, each row includes 8���10 hooks and the lemnisci are slightly longer than the proboscis receptacle, while in the second, each row includes 24���25 hooks and the lemnisci are slightly shorter than the proboscis receptacle. Sclerocollum saudii sp. nov. is similar to S. rubrimaris, but significantly differs in having a proboscis only armed with 10 rows of hooks (8���9 hooks in each row), smaller proboscis hooks (anterior hooks 34���38, intermediate hooks 36���40, posterior hooks 24���30 vs. 34 ���44, 44��� 50 and 30���38 �� in length), lemnisci much longer than proboscis receptacle (about 2.3 as proboscis receptacle length vs. slightly longer than the proboscis receptacle) and in having much smaller eggs (20���28 �� 6���10 vs. 55���72 �� 14���16 ��). These differences in proboscis hooks, lemnisci length and egg dimensions are specific, and usually considered as key characteristics to differentiate species of acanthocephala (see Amin 1985); their combination is sufficient to consider the present species as a new one. Excystation and activation of acanthocephalan cystacanths has been examined in only three species: Moniliformis dubius Meyer, 1933 (see Graff and Kitzman 1965), Echinorhynchus truttae Schrank, 1788 (see Awachie 1966) and Polymorphus minutus Goeze, 1782 (see Lackie 1974). Activation is thought to be mainly stimulated superficially by the bile of the host or by the osmotic pressure of the surrounding medium. The exact role of the bile is not fully understood (Khanna 2004). In S. saudii sp. nov., excystment of the active juvenile is through a tubular portion released from the cyst, and is preceded by squirts of a foamy material. Thus, juvenile growth may lead to an increasing pressure on the inside of the cyst which could be instrumental in impelling the tubular portion through which the juvenile escapes from the cyst., Published as part of Al-Jahdali, Mohammed O., 2010, Helminth parasites from Red Sea fishes: Neowardula brayi gen. nov., sp. nov. (Trematoda: Mesometridae Poche, 1926) and Sclerocollum saudii sp. nov. (Acanthocephala: Cavisomidae Meyer, 1932), pp. 57-65 in Zootaxa 2681 on pages 61-64, DOI: 10.5281/zenodo.199330, {"references":["Amin, O. M., Nahhas, F. M., Abu-Hakima, R. (1984) On three acanthocephalan species from some Arabian Gulf fishes of the coast of Kuwait. Journal of Parasitology, 70, 168 - 170.","Diamant, A. (1989) Ecology of the acanthocephalan Sclerocollum rubrimaris Schmidt and Paperna, 1978 (Rhadinorhynchidae: Gorgorhynchinae) from wild populations of rabbitfish (genus Siganus) in the northern Red Sea. Journal of Fish Biology, 34, 387 - 398. DOI: 10.1111 / j. 1095 - 8649.1989. tb 03321. x","El-Naffar, M. K. I., Gobashy, A., El-Etreby, S. G. & Kardousha M. M. (1992) General survey of helminth parasite genera of Arabian Gulf fishes (Coasts of United Arab Emirates). Arab Gulf Journal of Science Research, 10, 99 - 110.","Martens, E. & Moens, J. (1995) The metazoan ecto- and endo-parasites of the rabbitfish, Siganus sutor (Cuvier and Valenciennes, 1835) off the Kenyan coast. International African Journal of Ecology, 33, 405 - 416.","Geets, A. & Ollevier, F. (1996) Endoparasitic helminths of the whitespotted rabbitfish (Siganus sutor Valenciennes, 1835) of the Kenyan Coast: Distribution within the host population and microhabitat use. Belgian Journal of Zoology, 126, 21 - 36. DOI: 10.1017 / S 0031182097001054","Hassanine, R. M. (2006) Acanthocephalans from Red Sea fishes. Family Cavisomidae Meyer, 1932: the seasonal cycle of Diplosentis nudus (Harada, 1938) Pichelin et Cribb, 2001 in a definitive fish host, and a comment on Sclerocollum Schmidt et Paperna, 1978. Acta Parasitologica, 51, 123.130. DOI: 10.2478 / s 11686 - 006 - 0019 - 3.","Hassanine, R. M. & Al-Jahdali, M. O. (2007) Ecological comments on the intestinal helminths of the rabbitfish Siganus rivulatus (Teleostei, Siganidae) from the northern Red Sea. Acta Parasitologica, 52, 278 - 285. DOI: 10.2478 / s 11686 - 007 - 0030 - 3","Amin, O. M. (1985) Classification. In: Crompton, D. W. T. & Nickol, B. B. (Eds), Biology of the Acanthocephala. Cambridge University Press, Cambridge, U. K., pp. 27 - 72.","Graff, D. J. & Kitzman W. B. (1965) Factors influencing the activation of acanthocephalan cystacanths. The Journal of Parasitology, 51, 424 - 29.","Awachie, J. B. E. (1966) The Development and Life History of Echinorhynchus truttae Schrank, 1788 (Acanthocephala). Journal of Helminthology, 40, 11 - 32. DOI: 10.1017 / S 0022149 X 00034040","Lackie, A. M. (1974) The activation of cystacanths of Polymorphus minutus (Acanthocephala) in vitro. Parasitology, 68, 135 - 146. DOI: 10.1017 / S 0031182000045674","Khanna, D. R. (2004) Biology Of Helminthes. Discovery Publishing House, USA. 456 pp."]}

Sclerocollum Schmidt et Paperna, 1978 The acanthocephalan genus Sclerocollum was erected by Schmidt and Paperna (1978) for S. rubrimaris Schmidt et Paperna, 1978 from the intestine of three fish species (Siganus rivulatus, S. rostratus and Pseudobalistes fuscus) in the Gulf of Eilat, Red Sea. They referred the genus to the family Rhadinorhynchidae Travassos, 1923 and subfamily Gorgorhynchinae Van Cleave et Lincicome, 1940, differentiating it from Neorhadinorhynchus Yamaguti, 1939 by the conspicuous sclerotised plaques which are embedded in the tegument at the anterior region of the trunk (versus absent) and by the basal hooks of the proboscis which alternate with each other (versus arranged at the same level to form a ring). These two characteristics were also observed by Schmidt and Paperna (1978) in the original specimens of Neorhadinorhynchus robustus (Edmonds, 1964) Golvan, 1969 (from Siganus lineatus on the Southern Great Barrier Reef). Therefore, they transferred this species to Sclerocollum as a new combination. In their revision of the family Diplosentidae Tubangui et Masilu��gan, 1937, Pichelin and Cribb (2001) transferred Neorhadinorhynchus and Sclerocollum to family Cavisomidae Meyer, 1932, and on the basis of a striking similarity, they considered them as synonyms of Diplosentis Tubangui et Masilu��gan, 1937. Accordingly, all species of Neorhadinorhynchus and Sclerocollum were transferred by Pichelin and Cribb (2001) to Diplosentis as new combinations. Hassanine (2006) agreed with Pichelin and Cribb (2001) in transferring Sclerocollum to family Cavisomidae, but retained it as a valid genus, stating that in its members, the basal hooks of proboscis alternate with each other (not forming ring), a character lacking in Diplosentis and its synonym, i.e. Neorhadinorhynchus, where the basal hooks of proboscis are at the same level and forming a ring. Accordingly, 2 species of Sclerocollum are currently recognized, i.e. S. rubrimaris Schmidt et Paprena, 1978 (type species) and S. robustus (Edmonds, 1964) Schmidt et Paprena, 1978., Published as part of Al-Jahdali, Mohammed O., 2010, Helminth parasites from Red Sea fishes: Neowardula brayi gen. nov., sp. nov. (Trematoda: Mesometridae Poche, 1926) and Sclerocollum saudii sp. nov. (Acanthocephala: Cavisomidae Meyer, 1932), pp. 57-65 in Zootaxa 2681 on page 60, DOI: 10.5281/zenodo.199330, {"references":["Schmidt, G. D. & Paperna, I. (1978) Sclerocollum rubrimaris gen. et sp. n. (Rhadinorhynchidae: Gorgorhynchinae), and other Acanthocephala of marine fishes from Israel. Journal of Parasitolology, 64, 846 - 850.","Hassanine, R. M. (2006) Acanthocephalans from Red Sea fishes. Family Cavisomidae Meyer, 1932: the seasonal cycle of Diplosentis nudus (Harada, 1938) Pichelin et Cribb, 2001 in a definitive fish host, and a comment on Sclerocollum Schmidt et Paperna, 1978. Acta Parasitologica, 51, 123.130. DOI: 10.2478 / s 11686 - 006 - 0019 - 3."]}