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Archive | 2013

Cestodes of the order Trypanorhyncha Diesing, 1863 from South-east Asia and Australia

Bjoern C. Schaeffner

A new genus of trypanorhynch cestode is described from two species of sharks, the sliteye shark Loxodon macrorhinus Müller & Henle and the straight-tooth weasel shark Paragaleus tengi (Chen) collected in the Makassar Strait (off Indonesian Borneo) and Sulu Sea (off Malaysian Borneo). Ancipirhynchusafossalis n. g., n. sp. possesses two bothria and a heteroacanthous, heteromorphous tentacular armature with three distinctive files of hooks on the external tentacle surface but lacks prebulbar organs and gland cells within the tentacular bulbs. The hook arrangement of alternating files on the external surface of the tentacle resembles that seen in the superfamily Otobothrioidea Dollfus, 1942 in the genus Fossobothrium Beveridge & Campbell, 2005. However, the new species lacks the defining characteristic of this group, i.e. the paired bothrial pits. A Bayesian inference (BI) analysis of 37 LSU sequences of trypanorhynchs from three superfamilies provided evidence supporting the taxonomic placement of Ancipirhynchusafossalis n. g., n. sp. within the Otobothrioidea.


Systematic Parasitology | 2011

Revision of Wenyonia Woodland, 1923 (Cestoda: Caryophyllidea) from catfishes (Siluriformes) in Africa

Bjoern C. Schaeffner; Miloslav Jirků; Zuheir N. Mahmoud; Tomáš Scholz

Tapeworms of the genus Wenyonia Woodland, 1923 (Caryophyllidea: Caryophyllaeidae), parasites of catfishes in Africa, are revised. This revision is based on material from large-scale sampling, in the Democratic Republic of the Congo, Kenya, Senegal and the Sudan between 2006 and 2009, and the examination of all of the type-specimens available. The following six species are considered valid and their redescriptions are provided: Wenyonia virilis Woodland, 1923 (type-species; new synonym W. kainjii Ukoli, 1972); W. acuminata Woodland, 1923; W. longicauda Woodland, 1937; W. minuta Woodland, 1923 (new synonym W. mcconnelli Ukoli, 1972); W. synodontis Ukoli, 1972; and W. youdeoweii Ukoli, 1972. A key to the identification of Wenyonia spp. is provided and numerous new hosts and geographical records are reported. A comparative phylogenetic analysis of partial sequences of the 28S rRNA gene of four species divided the monophyletic genus into two lineages, one represented by W. acuminata and W. minuta and another one composed of W. virilis and W. youdeoweii.


Systematic Parasitology | 2011

Ancipirhynchus afossalis n. g., n. sp. (Trypanorhyncha: Otobothriidae), from two species of sharks off Indonesian and Malaysian Borneo

Bjoern C. Schaeffner; Robin B. Gasser; Ian Beveridge

A new genus of trypanorhynch cestode is described from two species of sharks, the sliteye shark Loxodon macrorhinus Müller & Henle and the straight-tooth weasel shark Paragaleus tengi (Chen) collected in the Makassar Strait (off Indonesian Borneo) and Sulu Sea (off Malaysian Borneo). Ancipirhynchusafossalis n. g., n. sp. possesses two bothria and a heteroacanthous, heteromorphous tentacular armature with three distinctive files of hooks on the external tentacle surface but lacks prebulbar organs and gland cells within the tentacular bulbs. The hook arrangement of alternating files on the external surface of the tentacle resembles that seen in the superfamily Otobothrioidea Dollfus, 1942 in the genus Fossobothrium Beveridge & Campbell, 2005. However, the new species lacks the defining characteristic of this group, i.e. the paired bothrial pits. A Bayesian inference (BI) analysis of 37 LSU sequences of trypanorhynchs from three superfamilies provided evidence supporting the taxonomic placement of Ancipirhynchusafossalis n. g., n. sp. within the Otobothrioidea.


Electrophoresis | 2012

Mutation scanning-based analysis of anisakid larvae from Sillago flindersi from Bass Strait, Australia

Abdul Jabbar; Avalene T. W. Khoon; Teo X. Hui; Bjoern C. Schaeffner; Aaron R. Jex; Matthew J. Nolan; Andreas L. Lopata; Robin B. Gasser; Ian Beveridge

Anisakidosis is an important fish‐borne disease caused by the larvae of anisakid nematodes, which affects humans and a range of other animals. The accurate identification of members of this nematode group is central to investigating the epidemiology of the parasites and in the surveillance and control of anisakidosis. It is now well known that morphological identification alone does not allow specific identification, particularly of larval stages. To better understand the epidemiology of anisakid nematodes in southern Australian fishes and the potential risks posed to human health, a survey of 50 specimens of the commercially important fish, Sillago flindersi, from Bass Strait, Australia was conducted. We characterised anisakid larvae by PCR‐coupled mutation scanning, sequencing and phylogenetic analyses of the first and second internal transcribed spacers (ITS‐1 and ITS‐2) of nuclear ribosomal DNA. This study revealed that 92% of the S. flindersi examined were infected with anisakids (n=194), which were represented by seven genotypes. Phylogenetic analyses of the genotypes defined herein, together with reference sequence for Anisakis pegreffii and Hysterothylacium sp. from public databases (i.e. GenBank), revealed the presence of A. pegreffii (n=24), Hysterothylacium larval type IV (n=90) and Hysterothylacium larval type VIII (n=80) in S. flindersi. Thus, the PCR‐coupled mutation scanning approach employed herein is an effective tool for the genetic characterisation of anisakid nematodes for diagnostic and analytical purposes (nucleotide sequences reported in this paper are available in the GenBank database under accession nos. JN631796‐809).


Systematic Parasitology | 2012

Cavearhynchus, a new genus of tapeworm (Cestoda: Trypanorhyncha: Pterobothriidae) from Himantura lobistoma Manjaji-Matsumoto & Last, 2006 (Rajiformes) off Borneo, including redescriptions and new records of species of Pterobothrium Diesing, 1850

Bjoern C. Schaeffner; Ian Beveridge

A new genus of trypanorhynch cestode is described from the tubemouth whipray Himantura lobistoma Manjaji-Matsumoto & Last, 2006 in the South China Sea off Malaysian Borneo. Cavearhynchus foveatus n. g., n. sp. possesses four pedicellate bothria in a cruciform arrangement, a heteroacanthous, heteromorphous metabasal tentacular armature with five hooks per principle row and an alternating longitudinal file of intercalary hooks on the bothrial surface of each tentacle, but lacks prebulbar organs and gland-cells within the bulbs. It, thus, closely resembles taxa belonging to the lacistorhynchoid family Pterobothriidae Pintner, 1931. However, the new genus differs from other genera within this family in the possession of bothrial pits. Although a distinguishing characteristic of the superfamily Otobothrioidea Dollfus, 1942, representatives of this group exhibit two bothria and the bothrial pits are lined with spiniform microtriches, whereas the pit-like structures.of C. foveatus n. g., n. sp. entirely lack microtriches. Redescriptions of two species of Pterobothrium, namely P.lesteri Campbell & Beveridge, 1996 and P. platycephalum (Shipley & Hornell, 1906) Dollfus, 1930 are provided from material collected off Borneo and several localities off Australia. Moreover, new host and locality records are added for P. australiense Campbell & Beveridge, 1996 and P. pearsoni (Southwell, 1929) Beveridge & Campbell, 1989.


Journal of Parasitology | 2012

Description of a New Trypanorhynch Species (Cestoda) from Indonesian Borneo, with the Suppression of Oncomegoides and the Erection of a New Genus Hispidorhynchus

Bjoern C. Schaeffner; Ian Beveridge

Abstract: A new species of Oncomegas Dollfus, 1929 is described from the cowtail stingray, Pastinachus atrus (Macleay), collected in the Makassar Strait, Indonesian Borneo. Oncomegas trimegacanthus n. sp. possesses 2 oval bothria, gland cells within the bulbs, prebulbar organs, a distinctive basal armature with a single macrohook on the bothrial surface of the asymmetrical basal swelling, and a heteroacanthous, heteromorphous metabasal armature with 10 hooks per principle row. It differs from congeners by its possession of additional enlarged hooks at the base of the tentacle. Because of apparent morphological similarities, we suppress the genus Oncomegoides Beveridge & Campbell, 2005 with Oncomegas, and place the type and only species, Oncomegoides celatus Beveridge & Campbell, 2005, within Oncomegas as Oncomegas celatus n. comb. Three species of Oncomegas, namely, Oncomegas paulinae Toth, Campbell & Schmidt, 1992, Oncomegas australiensis Toth, Campbell & Schmidt, 1992, and Oncomegas aetobatidis Campbell & Beveridge, 2009, differ from other species, possessing testes posterior to the ovary and a metabasal armature consisting of tiny, relatively homeomorphous hooks, with more than 14 hooks per principle row. Based on these morphological differences, a new genus, Hispidorhynchus n. gen., is erected, with Hispidorhynchus australiensis n. comb. as the type species.


Systematic Parasitology | 2013

Redescriptions and new records of species of Otobothrium Linton, 1890 (Cestoda: Trypanorhyncha)

Bjoern C. Schaeffner; Ian Beveridge

Redescriptions are provided for five incompletely described species of Otobothrium Linton, 1890: Otobothrium alexanderi Palm, 2004 from two species of carcharhinid sharks, Carcharhinus cautus (Whitley) and C. melanopterus (Quoy & Gaimard) at three localities off northern Australia; O. australe Palm, 2004 based on material collected from the type-host and type-locality and from six additional myliobatid and carcharhinid host species off Western Australia, the Northern Territory and northern Queensland; O. insigne Linton, 1905 from Rhizoprionodon terraenovae (Richardson) and Sphyrna tudes (Valenciennes) in the Atlantic Ocean off Senegal and the Democratic Republic of the Congo; O. mugilis Hiscock, 1954, previously known only from larval stages, based on adults from five sphyrnid and carcharhinid definitive host species off northern Australia and Malaysian Borneo; and O. penetrans Linton, 1907 from material collected from two species of hammerhead sharks (Sphyrnidae) in the Red Sea off Jordan and the Indian Ocean off Western Australia. Additional host and locality records are added for the type-species, O. crenacolle Linton, 1890 and for O. carcharidis (Shipley & Hornell, 1906). Two descriptions are provided for Otobothrium spp. treated here as Otobothrium sp. 1 from C. melanopterus off northern Australia and Otobothrium sp. 2 from Sphyrna zygaena (Linnaeus) in the Gulf of California, Mexico.


Systematic Parasitology | 2013

Dollfusiella Campbell & Beveridge, 1994 (Trypanorhyncha: Eutetrarhynchidae) from elasmobranchs off Borneo, including descriptions of five new species

Bjoern C. Schaeffner; Ian Beveridge

Sampling of a large number of elasmobranchs from coastal waters off Borneo revealed the presence of five new species of Dollfusiella Campbell & Beveridge, 1994 (Trypanorhyncha: Eutetrarhynchidae), namely D. angustiformis n. sp., D. hemispinosa n. sp., D. spinosa n. sp., D. imparispinis n. sp. and D. parva n. sp. Dollfusiella angustiformis n. sp. is described from the spiral intestines of four species of the dasyatid stingray genus Himantura Müller & Henle from both the Indonesian and Malaysian parts of Borneo. All the other species were obtained from Malaysian Borneo. Dollfusiella hemispinosa n. sp. is described from the spiral intestines of three species of Himantura, whereas D. spinosa n. sp. was obtained from several specimens of Pastinachus solocirostris Last, Manjaji & Yearsley (Dasyatidae) as well as from Taeniura lymma 1 (sensu Naylor et al., 2012) (Dasyatidae), Neotrygon kuhlii 2 (sensu Naylor et al., 2012) (Dasyatidae), and Glaucostegus cf. typus (sensu Naylor et al., 2012) (Rhinobatidae). Dollfusiella imparispinis n. sp. is described from the spiral intestine of a single specimen of Chiloscyllium punctatum Müller & Henle (Hemiscyllidae) from the South China Sea off Sarawak, whereas D. parva n. sp. was obtained from several species of Himantura. Specimens of the five novel taxa possess scoleces covered with enlarged microtriches, a morphological characteristic exhibited by several other congeners. However, the new species differ from all congeners by possessing unique patterns of oncotaxy as well as combinations of additional morphological features. The number of valid species within Dollfusiella is increased to 26. For this reason, a key for the species of Dollfusiella is provided. Furthermore, novel information on hosts and geographic distribution is provided for two previously described species of Dollfusiella, D. michiae (Southwell, 1929) and D. spinulifera (Beveridge & Jones, 2000). The latter species differs slightly from the original description and shows a much higher variability with regard to the lengths of the scolex and muscular bulbs and the number of testes. These variable characters subdivided specimens of D. spinulifera into relatively distinct groups. However, the specimens did not differ in their oncotaxy and are considered to represent a single variable species.


Systematic Parasitology | 2013

Pristiorhynchus palmi n. g., n. sp. (Cestoda: Trypanorhyncha) from sawfishes (Pristidae) off Australia, with redescriptions and new records of six species of the Otobothrioidea Dollfus, 1942

Bjoern C. Schaeffner; Ian Beveridge

A new genus of trypanorhynch cestodes, Pristiorhynchus n. g. (Otobothrioidea: Otobothriidae), is described from two species of modern sawfishes (Pristidae) from off northern Australia. Pristiorhynchus palmi n. g., n. sp. is characterised by an acraspedote scolex with two bothria, paired bothrial pits on the posterior margins of each bothrium, the absence of gland-cells within the bulbs and prebulbar organs, a retractor muscle inserting at the posterior region of the elongate bulbs, a characteristic basal tentacular armature with dispersed billhooks and a heteroacanthous atypical metabasal armature with five principle and three intercalary hooks. Furthermore, redescriptions are provided for Symbothriorhynchus tigaminacantha Palm, 2004, Parotobothrium balli (Southwell, 1929) and Pseudotobothrium arii (Bilqees & Shaukat, 1976). Observations of adult worms revealed novel information on the segment morphology, which has not been described for these three species. Specimens of Proemotobothrium linstowi (Southwell, 1924), Pr. southwelli Beveridge & Campbell, 2001 and Fossobothrium perplexum Beveridge & Campbell, 2005 collected from elasmobranchs from several sampling localities off Australia revealed additional information on host range and geographical distribution.


Systematic Parasitology | 2014

Review of the genus Eutetrarhynchus Pintner, 1913 (Trypanorhyncha: Eutetrarhynchidae), with the description of Eutetrarhynchus beveridgei n. sp.

Bjoern C. Schaeffner

The genus Eutetrarhynchus Pintner, 1913 is revised. Eutetrarhynchus beveridgei n. sp. is described from the spiral intestine of the dwarf whipray, Himantura walga (Müller & Henle) (Myliobatiformes: Dasyatidae), from the South China Sea off the Malaysian part of Borneo. The new species is characterised by a slender, elongate scolex, two oval bothria, muscular bulbs, retractor muscles inserting at the base of the bulbs, and the presence of gland-cells and prebulbar organs. The tentacular armature is typical heteroacanthous with heteromorphous hooks. Eutetrarhynchus beveridgei n. sp. is allocated to the genus due to its distinct segment morphology featuring two internal seminal vesicles and scattered testes occupying the complete intervascular space. It differs from congeners in its relatively small size, much smaller scolex regions and in the presence of a basal armature with a distinct basal swelling. Eutetrarhynchus cortezensis Friggens & Duszynski, 2005 is transferred to Dollfusiella Campbell & Beveridge, 1994, as D. cortezensis n. comb., on the basis of its segment morphology, with testes in a linear arrangement and the absence of internal seminal vesicles. A new generic diagnosis and a key for the identification of species of Eutetrarhynchus is provided.

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Aaron R. Jex

University of Melbourne

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Abdul Jabbar

University of Melbourne

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Teo X. Hui

University of Melbourne

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Miloslav Jirků

Academy of Sciences of the Czech Republic

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Tomáš Scholz

Academy of Sciences of the Czech Republic

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