Von Linstow Research Articles

Genetical and Morphological Identification of Prosthogonimus pellucidus (Digenea, Prosthogonimidae) in Grus japonensis

Species of the family Prosthogonimidae are considered the most pathogenic trematodes of poultry and wild birds worldwide, causing heavy economic losses in many countries. Prosthogonimosis was a common parasitic disease of Grus japonensis (Müller, 1776) which caused inflammation of the cloaca and bursa of Fabricius and even death. Morphological identifications of Prosthogonimus species are easily confusing; therefore, molecular characterization is used for discrimination. The present study was conducted to identify Prosthogonimus species at Zhalong National Nature Reserve, northeast of China. Considering the morphological variability and wide host range of individual Prosthogonimus species, a combination of both morphological and molecular analyses is indispensable for the valid identification of this parasite and the internal transcribed spacer (ITS) region was amplified for the sequence analysis and phylogenetic analysis. The results of molecular analysis together with phylogenetic reconstruction indicated that the Prosthogonimus pellucidus (von Linstow, 1873) in this study form a single cluster with P. pellucidus, revealing potentially high diversity within the genus Prosthogonimus. Classification of Prosthogonimus species seems to be unrelated to the host and may be related to geographical location. These data provide a significant resource of molecular markers for studying the taxonomy, population genetics, and systematics of Prosthogonimidae.

Supplemental description of Benedenia seriolae (Yamaguti, 1934) Meserve, 1938 (Monogenoidea: Capsalidae) and first record of the parasite infecting a wild greater amberjack, Seriola dumerili (Risso, 1810) Hureau and Tortonese, 1973 (Carangiformes: Carangidae) from the northern Gulf of Mexico

We herein provide a supplemental description of Benedenia seriolae (Yamaguti, 1934) Meserve, 1938 (Monogenoidea: Capsalidae Baird, 1853) based on specimens we collected from the skin of wild-caught greater amberjack (Seriola dumerili) in the northern Gulf of Mexico (GOM). Our specimens of B. seriolae from the GOM resemble those of Benedenia humboldti Baeza, Sepúlveda, and González, 2019 (from yellowtail amberjack, Seriola lalandi Valenciennes, 1833 [Carangidae] off Chile) by having a large body (>7000 μm in total length), non-overlapping anterior and posterior hamuli, an entirely sinistral and convoluted vas deferens, and a common genital pore as well as by lacking glands of Goto. It differs from B. humboldti by the shape of the penis tip. The 28S rRNA gene sequence differed from that of B. seriolae (from Japan) by 8 bp (1.1 %) and B. humboldti by 13 bp (2.8 %–1.7 %). The phylogenetic analysis recovered our sequences of B. seriolae sister to conspecific sequences from Japan, with that clade sister to B. humboldti from Chile. Benedenia was paraphyletic, suggesting some systematic revision to the genus could be warranted. Of 25 Benedenia spp., only Benedenia hendorffii (von Linstow, 1889) Odhner, 1905 had been reported previously from the GOM. Benedenia seriolae had previously not been reported from wild greater amberjack (previous records from greater amberjack were from sea cages only). This is also the first record of B. seriolae from the Northwestern Atlantic Ocean (GOM).

Novel gene arrangement in the mitochondrial genome of Aspersentis megarhynchus (Acanthocephala, Echinorhynchida, Heteracanthocephalidae), and its phylogenetic implications.

The Heteracanthocephalidae Petrochenko, 1956 is a rare family of acanthocephalans mainly parasitic in fishes. The pattern of mitogenomic evolution of the Heteracanthocephalidae is still unknown, and the phylogenetic relationships of the Heteracanthocephalidae with the other 14 families within the order Echinorhynchida remain unclear. In the present study, the complete mitochondrial genome of Aspersentis megarhynchus (von Linstow, 1892) Golvan, 1960 was sequenced and annotated for the first time, which represents the first mitogenomic data for the genus Aspersentis and also for the family Heteracanthocephalidae. The mitogenome of A. megarhynchus has 14,661 bp and includes 36 genes, containing 12 protein-coding genes (PCGs) (missing atp8), 22 tRNA genes, and 2 ribosomal RNAs (rrnS and rrnL), plus two non-coding regions. Comparative mitochondrial genomic analysis revealed that the presence of translocations of several tRNA genes (trnV, trnE, and trnT) and the gene arrangement in the mitogenome of A. megarhynchus represents a new type in Acanthocephala. Moreover, the mitogenomic phylogenetic results based on concatenated amino acid sequences of 12 protein-coding genes strongly supported the validity of the Heteracanthocephalidae and suggested close affinity between the Heteracanthocephalidae and Echinorhynchidae in the order Echinorhynchida.

A molecular and ecological study of Macracanthorhynchus ingens (von Linstow, 1879) (Acanthocephala: Archiacanthocephala), in its paratenic and definitive hosts in southeastern Mexico and the Eastern USA.

The acanthocephalan Macracanthorhynchus ingens (von Linstow 1879) (Acanthocephala: Archiacanthocephala) is a parasite that infects the gut of carnivores (racoons, coyotes, wolves, foxes, badgers, skunks, opossum, mink and bears) as an adult and the body cavity of lizards, snakes, and frogs as a cystacanth in the Americas. In this study, adults and cystacanths of M. ingens from southeastern Mexico and southern Florida, USA, were identified morphologically by having a cylindrical proboscis armed with 6 rows of hooks each with 6 hooks. Hologenophores were used to sequence the small (SSU) and large (LSU) subunits of ribosomal DNA and cytochrome c oxidase subunit 1 (cox 1) from mitochondrial DNA.Phylogenetic analysis of the new SSU and LSU sequences of M. ingens placed them in a clade with other sequences available in GenBank identified as M. ingens. The cox 1 tree showed that the nine new sequences and six previously published sequences of M. ingens from the USA form a clade with other sequences previously identified as M. ingens from GenBank. The intraspecific genetic divergence among isolates from the Americas ranged from 0 to 2%, and in combination with the phylogenetic trees confirmed that the isolates belonged to the same species. The cox 1 haplotype network inferred with 15 sequences revealed 10 haplotypes separated from each other by a few substitutions. Rio Grande Leopard Frogs and Vaillant´s Frogs harbored cystacanths with low prevalence, 28% and 37% respectively, in Mexico. Brown Basilisks, an invasive lizard in Florida, USA, had high values of prevalence, 92% and 93% in males and females, respectively. Females harbored more cystacanths than males (0-39 vs 0-21) for unknown reasons that may, however, be related to ecological differences.

Morphology of Streptocara crassicauda and S. recta, with a Review of the Genus Streptocara (Nematoda: Acuariidae) and an Identification Key to Its Species

The cosmopolitan genus Streptocara Railliet, Henry and Sisoff, 1912 (Nematoda: Acuariidae) comprises parasites of the upper alimentary tract of aquatic and, rarely, terrestrial birds. Two species of the genus Streptocara are redescribed from Bulgaria by means of light and scanning electron microscopy: Streptocara crassicauda (Creplin, 1829), based on specimens from Larus genei, Larus minutus (Laridae) and Aythya ferina (Anatidae), and Streptocara recta (von Linstow, 1879) from Podiceps nigricollis (Podicipedidae). This is the first record of S. recta from Bulgaria. The host and distribution records of the species of the genus Streptocara are reviewed. Six species are recognised as valid. Streptocara crassicauda (Creplin, 1829), S. californica (Gedoelst, 1919), S. formosensis Sugimoto, 1930 and S. incognita Gibson, 1968, seem to be parasites well-adapted to birds of the family Anatidae (Anseriformes) and occasionally found in other birds, whereas S. recta (von Linstow, 1879) and S. longispiculata Gibson, 1968, are specialists of Podicipediformes and Gaviiformes, respectively. Streptocara indica Fotedar and Chishti, 1974, is recognised as a junior synonym of S. crassicauda, and Schistogendra oligopapillata Zhang and An, 2002, is considered as a junior synonym of Streptocara formosensis Sugimoto, 1930. An identification key to the species of the genus Streptocara is proposed.

A new definitive host for Moniliformis cestodiformis (Acanthocephala: Moniliformidae): first report of a naturally infected European hedgehog (Erinaceus europaeus).

European hedgehogs, Erinaceus europaeus (Linnaeus, 1758), are small mammals found in western Europe and also in parts of northern Europe. They can be seen in rural, suburban and urban areas, but are usually found in grassland with edge habitats. These animals are omnivorous and serve as definitive or paratenic hosts for several parasites, including acanthocephalans (phylum Acanthocephala). During necropsy of a European hedgehog, a single adult parasite was collected from the intestinal lumen and preserved in 70% ethanol. After morphological evaluation of the specimen, it was identified as Moniliformis cestodiformis (von Linstow, 1904) (Acanthocephala: Moniliformidae). This is the first report of M. cestodiformis in a European hedgehog, as well as in Europe. More epidemiological studies need to be carried out to map the location and prevalence of this parasite in Portugal and the European continent.

First Report of Zoonotic Tapeworms, Dibothriocephalus latus (Linnaeus, 1758) and D. dendriticus (Nitzsch, 1824), and Other Endohelminth Parasites in Chinook Salmon, Oncorhynchus tshawytscha, in Chile

In the present study, the zoonotic tapeworms Dibothriocephalus latus and Dibothriocephalus dendriticus were identified for the first time, using morphological and molecular procedures, in a population of introduced Chinook salmon in Chile. The morphological differences observed between plerocercoids of D. latus and D. dendriticus were, respectively, a retracted and obscured scolex versus one that is always visible and only partially retracted after cold fixation; extension of frontal glands; size, types of, density of, and distribution of microtriches; and number of parenchymal longitudinal muscle bundles within 50-µm spaces. With scanning electronic microscopy, both species presented 3 types of microtriches: coniform and uncinated spinitriches, and capilliform filitriches. In the body region, D. latus presents all types of microtriches, but D. dendriticus only possessed capilliform filitriches. Multiplex PCR targeting cox1 of Diphyllobothriidae and subsequent sequence analysis allowed for confirmation of species identity. All adult Chinook salmon examined (32–60 cm total length) were infected by Dibothriocephalus spp. with a range of 15–192 plerocercoids. Plerocercoids were found in the stomach, intestine, liver, spleen, gonads, swim bladder, peritoneum, heart, and muscles. The prevalence of infected salmon, the percentage of plerocercoids, and the mean intensity of D. latus in the muscles were 3, 4, and 2 times greater than that of D. dendriticus. Histological examination of the stomach, liver, spleen, gonads, and muscle revealed the presence of 1 or more encysted or free plerocercoids. In most cases, varying degrees of chronic inflammation and low presence of neutrophils were observed. The prey consumed by Chinook salmon included the native fish, Galaxias maculatus, and unidentified fish and amphipods. Other identified endohelminths were Derogenes lacustris Tsuchida, Flores, Viozzi, Rauque, and Urabe, 2021 in the stomach, Camallanus corderoi Torres, Teuber and Miranda, 1990 in the intestine, larvae of Contracaecum sp. in the intestinal wall, and Acanthocephalus tumescens (von Linstow, 1896) in the intestine. All identified parasites are reported for the first time in Chinook salmon from Chile.

A new species of Arostrilepis from Ellobius tancrei (Rodentia: Cricetidae) in Mongolia.

AbstractCestodes of the genusArostrilepisMas-Coma and Tenora 1997 have a Holarctic distribution with 16 species occurring among 28 species of mostly arvicoline hosts. The type species of the genus isArostrilepis horrida(von Linstow, 1901), described initially asTaenia horridavon Linstow, 1901, from murine rodents in Lower Saxony (Niedersachsen), Germany. Here we report the first helminth parasite from the mole-vole,Ellobius tancrei, in Mongolia which is the first subterranean rodent known to be infected withArostrilepisin the Palearctic. In addition, we describe a new species:Arostrilepis batsaikhanin. sp. which most closely resemblesA. microtisGulyaev and Chechulin 1997, differing from this species with a genetic distance of about 4% (using cytochrome-b) and by having distinctly large cirrus spines, testes that are larger and fill the whole segment measured anterior–posterior and larger eggs.

Genetic characterisation of Tanqua (von Linstow, 1879) (Nematoda: Gnathostomatidae) larval forms including new host and locality records.

In an unrelated study of spotted snakehead fish Channa punctata (Bloch) of family Channidae (N = 103) from Bangladesh, ten fish had taupe and clear coloured cysts attached to the intestinal mesentery. Investigation of the cysts revealed larval nematodes. The larvae were damaged and not suitable for detailed morphological study, however, key features such as tooth like projections of the pseudolabia and lateral pseudolabium were observed in specimens with undamaged cephalic regions. Molecular characterisation was undertaken and although the parasite genetic material was poor, five of the twelve nematode larvae through sequencing of the 18S ribosomal RNA gene, showed 98.17% match with sequences assigned for Tanqua tiara (accession number JF934728) deposited in GenBank. The prevalence of infection was 9.7% and the mean intensity 2.70. Tanqua has not previously been identified in fish, or from the definitive host, the Asian water monitor Varanus salvator (Laurenti, 1768) of family Varanidae (class Reptilia), in Bangladesh. Therefore, this study represents a new host and locality record for this nematode species. In many previous reports from this region, nematode larvae have been identified morphologically and assigned to a diverse range of nematode genera. Some confusion therefore exists regarding their accuracy and further investigations are required using molecular methodology to clarify the species of larval nematodes which infect edible fish in Bangladesh.

Detection and molecular characterisation of intestinal parasites in the South China tiger Panthera tigris amoyensis (Hilzheimer).

Parasitic infections of the South China tigers in the Meihua Mountains have not been explored previously. Faeces of 22 South China tigers from the China Tiger Park in the Meihua Mountains were examined. Eggs of ascaridoid nematodes and oocysts of coccidia were detected by Mini-FLOTAC assay. Morphological observation and molecular characterisation of the oocysts were carried out. The prevalence of Toxascaris leonina (von Linstow, 1902) was 18% (4/22), and the highest egg per gram (EPG) count in the faeces was 27,150. The prevalence of Cystoisospora sp. was 45% (1 0/22) and the highest oocysts per gram (OPG) in the faeces was 6,000. In addition, we found one ascaridoid nematode in the South China tiger's faeces and was molecularly and morphologically identified as T. leonina. The oocysts in the faeces were sporulated in vitro and identified as Cystoisospora sp. Amplification of full-length internal transcribed spacers (ITS) resulted in sequences 1,622 bp long. Using the sequences, Cystoisospora sp. of the South China tiger was closest to Isospora belli (Wenyon, 1923) and Cystoisospora suis (Biester, 1934).

COMUNIDAD DE HELMINTOS DE POLLOS CASEROS (GALLUS GALLUS DOMESTICUS LINNAEUS, 1758) EN SEROPÉDICA, RIO DE JANEIRO, BRASIL

The domestic chicken, Gallus gallus domesticus Linnaeus, 1758, is an important component of the agribusiness segment, and Brazil is one of the world’s largest broiler producers and exporters. The present study aimed to characterize the composition and structure of the helminth community of backyard chickens, G. g. domesticus, in Seropedica, Rio de Janeiro, Brazil. Fifty-five adult chickens were studied. The overall helminth species richness was 12. The nematodes Capillaria sp. and Heterakis gallinarum (Schrank, 1788), recovered from small intestine and cecum, respectively, presented the highest prevalence and mean abundance and were considered central species. In addition, these species presented the highest values of frequency of dominance and Berger. The pairs of helminth species Amoebotaenia cuneata (von Linstow, 1872) – Raillietina tetragona (Molin, 1958); Davainea proglottina (Davaine, 1860) – A. cuneata; and H. gallinarum – Capillaria sp. showed significant positive correlation between their abundance and prevalence. Gongylonema ingluvicola Ransom, 1904 and H. gallinarum showed significant correlation between host sex and helminth abundance, while there was no correlation between host sex and helminths prevalence. The knowledge of helminth community structure in free-range chickens is important to adopt better measures for control and prevention of helminth infections.

New perspectives on Aspersentis Megarhynchus (Acanthocephala: Heteracanthocephalidae) from Notothenia Coriiceps Richardson (Nototheniidae) in the West Antarctic, with emended generic diagnosis.

A number of variable descriptive accounts of Aspersentis megarhynchus (von Linstow, 1892) Golvan, 1960 have been reported from specimens collected from many species of fish in various locations off Antarctic islands. We have described a new population from Notothenia coriiceps Richardson (Nototheniidae) off Galindez Island, West Antarctica, and features not previously reported, resolved the taxonomic controversies and nomenclature, and emended and updated the generic diagnosis taking into account the newly observed structures. These are depicted in microscopic images and include the outer spiral wall of the proboscis receptacle, the thicker dorsal wall of the receptacle compared to the ventral wall, parts of the female reproductive system, the separate cement gland ducts, the dorsal position of the male gonopore and more detail of proboscis hooks and trunk spines. It is surprising that the newly observed features were missed from the many descriptions of A. megarhynchus created since the original description. The variability in A. megarhynchus is noted with a comparison of the morphometrics of our specimens vs. those in six other descriptions. We also analysed the metal composition of hooks and spines using energy-dispersive X-ray analysis and concluded a molecular characterization of the species based on 18S DNA gene, with related phylogenetic analyses.

Comparative study of four known species of the genus Acrobeles von Linstow, 1877 (Nematoda, Cephalobidae) with ‘single’ and ‘double’ cuticle from coastal dunes in Spain

The nematode genus Acrobeles is composed of two morphological groups distinguished by the presence ('double' cuticle) or absence ('single' cuticle) of the refringent inner layer of the cuticle. In the present study, four species of this genus, two with 'single' cuticle (Acrobeles ciliatus and Acrobeles cylindricus) and two with 'double' (Acrobeles aenigmaticus and Acrobeles complexus) are studied from coastal dunes in Spain. This study provides detailed morphological and morphometrical analyses for the four species, while molecular analysis, based on 18S and 28S ribosomal DNA, is provided for A. complexus. The four species are studied with scanning electron microscopy, which is obtained for the first time for A. cylindricus. These analyses revealed morphological and molecular differentiations between both groups, appearing as two related monophyletic entities. The subgenera Acrobeles and Seleborca, formerly considered as separate genera, are proposed to accommodate both groups.

Pre-existing Microfilarial Infections of American Robins (Passeriformes: Turdidae) and Common Grackles (Passeriformes: Icteridae) Have Limited Impact on Enhancing Dissemination of West Nile Virus in Culex pipiens Mosquitoes (Diptera: Culicidae).

Microfilariae (MF) are the immature stages of filarial nematode parasites and inhabit the blood and dermis of all classes of vertebrates, except fish. Concurrent ingestion of MF and arboviruses by mosquitoes can enhance mosquito transmission of virus compared to when virus is ingested alone. Shortly after being ingested, MF penetrate the mosquito's midgut and may introduce virus into the mosquito's hemocoel, creating a disseminated viral infection much sooner than normal. This phenomenon is known as microfilarial enhancement. Both American Robins and Common Grackles harbor MF-that is, Eufilaria sp. and Chandlerella quiscali von Linstow (Spirurida: Onchocercidae), respectively. We compared infection and dissemination rates in Culex pipiens L. mosquitoes that fed on birds with and without MF infections that had been infected with West Nile virus (WNV). At moderate viremias, about 107 plaque-forming units (pfu)/ml of blood, there were no differences in infection or dissemination rates among mosquitoes that ingested viremic blood from a bird with or without microfilaremia. At high viremias, >108.5 pfu/ml, mosquitoes feeding on a microfilaremic Grackle with concurrent viremia had significantly higher infection and dissemination rates than mosquitoes fed on viremic Grackles without microfilaremia. Microfilarial enhancement depends on the specific virus, MF, and mosquito species examined. How virus is introduced into the hemocoel by MF differs between the avian/WNV systems described here (i.e., leakage) and various arboviruses with MF of the human filarid, Brugia malayi (Brug) (Spirurida: Onchocercidae) (i.e., cotransport). Additional studies are needed to determine if other avian species and their MF are involved in the microfilarial enhancement of WNV in nature.

English

A total of 30 specimens of house sparrow Passer domesticus biblicus Hartert, 1904 (15 females and 15 males) were collected from gardens of some houses in Baghdad city; all birds were dissected to identify the parasites in vesicle, gizzard, intestine, gall bladder and caecum. One species of trematodes Brachydistomum microscelis (Yamaguti, 1933) was found in the gall bladder and two species of cestodes Anonchotaenia globata (von Linstow, 1879) and Raillietina tetragona (Molin, 1858) were found in the small intestine of house sparrow. Morphologic and morphometric measurements were considered. The genus Brachydistomum Travassos, 1944 is being recorded for the first time in Iraq in the gall bladder of house sparrow, as it was not previously recorded from birds in Iraq.

Redescription of Tanqua tiara (von Linstow, 1879) Blanchard, 1904 (Nematoda: Gnathostomatidae) from Varanus flavescens (Hardwicke and Gray, 1827) (Reptilia: Varanidae) from Birbhum district, West Bengal, India.

Tanqua tiara (von Linstow, 1879) Blanchard, 1904, recovered from the stomach of water monitor lizard, Varanus flavescens (Hardwicke and Gray, 1827), collected from the Dubrajpur town, Birbhum district of West Bengal, India, is redescribed with light as well as scanning electron microscopy. This species is characterised by presence of two large lateral pseudolabia followed by massive cephalic bulb. The inner surface of each pseudolabium is folded into five rounded tooth-like formations which fit into corresponding folds on adjacent pseudolabium. Spicules are equal and similar. Gubernaculum is absent. Caudal papillae are sessile and five pairs in number. Present nematode differs from earlier descriptions of T. tiara in having five pairs of caudal papillae and an unpaired median precloacal papilla. Position of phasmids has also been reported in present study. Actual structure of cervical papillae and cuticular striations have been shown in present SEM studies which are also different from earlier descriptions. Dubrajpur is recorded as new geographical area for this parasite.

Review of records of hymenolepidids (Eucestoda: Hymenolepididae) from dormice (Rodentia: Gliridae) in Europe, with a redescription of Armadolepis spasskyi Tenora & Baruš, 1958 and the description of A. genovi n. sp.

Armadolepis (Armadolepis) spasskyi Tenora & Baruš, 1958 is redescribed on the basis of the type-series consisting of the holotype from the garden dormouse Eliomys quercinus (Linnaeus) (type-host) and a paratype from the forest dormouse Dryomys nitedula (Pallas); the occurrence of this species in the fat dormouse Glis glis (Linnaeus) cannot be confirmed due to the lack of specimens from this host species both in the type-series and other studied samples. The main corrections in the diagnostic characters of A. spasskyi are related to the number and length of the rostellar hooks (12 hooks, 12-14 µm long versus 16-19 hooks, 15.3-17.1 µm long in the original description) and the position of the testes in triangle (versus in line as originally described). Specimens originally identified as Hymenolepis myoxi (Rudolphi, 1819) by Genov (1984) from the fat dormouse G. glis from Bulgaria are described as Armadolepis (Bremserilepis) genovi n. sp. The new species differs from the congeners by the presence of a rudimentary rostellum and rudimentary rostellar hooks; the new species differs from the other two species of the subgenus, A. (B.) myoxi and A. (B.) longisoma, by its longer cirrus-sac (196-240 µm), scolex diameter of 180-300 µm (wider than that of A. myoxi and narrower than that of A. longisoma) and wider ovary (220-310 µm). Cestodes previously reported as Hymenolepis myoxi from E. quercinus from Switzerland and France (western and north-western Alps) are now identified as Armadolepis (A.) jeanbaeri Makarikov, 2017. Cestodes from G. glis from Switzerland and Slovakia, previously identified as Hymenolepis sulcata (von Linstow, 1879), are now identified as Armadolepis (B.) myoxi (sensu stricto). The position of Hymenolepis (s.l.) sciurina Cholodkovsky, 1913 as a subspecies of A. myoxi is rejected and it is considered a species inquirenda.

Amendment of Rostellotaenia Freze, 1963 (Cestoda: Proteocephalidae) from African monitors (Varanus spp.) and a redescription of its type-species, R. nilotica (Beddard, 1913).

Based on morphological evaluation of type-specimens and new material collected in three species of monitor lizards (Squamata: Varanidae), the diagnosis of the monotypic Rostellotaenia Freze, 1963 (Proteocephalidae: 'Acanthotaeniinae') is amended. The genus differs from Acanthotaenia von Linstow, 1903, with which it was previously synonymised, by the shape of the scolex with a wide, dome-shaped rostellum, the posterior extent of the uterus, which does not overpass the ovarian isthmus posteriorly, well-developed retractor muscles connecting the rostellum with the neck region, absence of a well-developed, ring-like vaginal sphincter, shorter and wider proglottides, and geographical distribution (Ethiopian region only). The type- and only species, R. nilotica (Beddard, 1913), is redescribed and two new definitive hosts, Varanus albigularis Daudin and V. exanthematicus (Bosc), are reported. Host specificity of R. nilotica, which exhibits remarkable morphological variability, is stenoxenous, i.e. it occurs in several congeneric species of African monitor lizards, unlike species of Acanthotaenia, which are strictly specific (oioxenous).

New species and new records of species of Cloacina von Linstow, 1898 (Nematoda: Strongylida) parasitic in the western scrub wallaby, Notamacropus irma (Jourdan) (Marsupialia: Macropodidae) from Western Australia.

The helminth parasites of the western scrub wallaby or black-glove wallaby, Notamacropus irma (Jourdan) which occurs in Western Australia are relatively poorly documented. Six new species of the strongyloid genus Cloacina von Linstow, 1898 (Strongylida: Chabertiidae) are described namely C. asymmetrica n. sp., C. brazellei n. sp., C. harriganae n. sp., C. hobbsi n. sp., C. middletoni n. sp. and C. woodi n. sp. A redescription of C. laius Beveridge, 1999 from the same host species is included. Molecular sequence data (ITS1 and ITS2 ribosomal DNA) were obtained for C. asymmetrica, C. brazellei, C. hobbsi, C. middletoni and from the previously described species C. themis Beveridge, 1998 occurring in the same host species. Phylogenetically, C. asymmetrica, C. hobbsi and C. middletoni formed a distinct clade, suggesting the possibility of within-host speciation. Cloacina themis clustered with a group of morphologically distinctive species in a separate clade and C. brazellei clustered in a third clade but with poor support. This pattern of congeners in a single host species occurring in multiple clades mirrors the situation in other kangaroos and wallabies. Species of Cloacina from N. irma reported thus far therefore consist of a series of species found only in this host, with two species (C. brazellei and C. laius) shared with the sympatric macropodid Setonix brachyurus (Quoy & Gaimard).

Revision of Acanthotaenia von Linstow, 1903 (Cestoda: Proteocephalidae), parasites of monitors (Varanus spp.), based on morphological and molecular data

A morphological and molecular phylogenetic study of proteocephalid tapeworms of the genus Acanthotaenia von Linstow, 1903, parasites of monitors (Varanidae), was carried out. The type species, A. shipleyi von Linstow, 1903, which was originally described based on an immature specimen from Sri Lanka, is redescribed based on new material from the type host, Varanus salvator, in Sri Lanka, Malaysia, and Vietnam, and its neotype is designated. In addition, Acanthotaenia susanae n. sp. is described from Varanus nebulosus in Vietnam. The new species differs from congeners by the large size of the scolex, width of the rostellum and the number of testes. New molecular data (sequences of lsrDNA and cox1) revealed Acanthotaenia paraphyletic with the inclusion of Australotaenia bunthangi de Chambrier & Scholz, 2012, a parasite of Enhydris enhydris (Ophidia: Homalopsidae) in Cambodia. Molecular data confirm a wide distribution of A. shipleyi (isolates from Malaysia and Vietnam were almost identical) and indicate a strict host specificity (oioxeny) of individual species of the genus. Type specimens of four species made it possible to supplement their morphological descriptions. A survey of all species of Acanthotaenia recognised as valid is presented and the following taxonomic changes are proposed: Acanthotaenia pythonis Wahid, 1968 described from the green python, Morelia viridis, in a zoo, is transferred to Kapsulotaenia as Kapsulotaenia pythonis (Wahid, 1968) n. comb., because it possesses intrauterine eggs grouped in capsules. Acanthotaenia gracilis (Beddard, 1913) from Varanus varius in Australia is considered to be species inquirenda because its original descriptions did not contain sufficient data for adequate circumscription and differentiation from congeners and type material was not available. Generic diagnosis of Acanthotaenia is amended and a key to its seven species is provided.