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The purpose of this application, under Article 23.9.5 of the ICZN Code, is to conserve current usage of the name Taenia asiaticaEom & Rim, 1993 (Cestoda, Cyclophyllidea, Taeniidae) for a human-infecting species of East, Southeast and South Asian Taenia saginata-like tapeworm by disregarding the priority of its senior primary homonym Taenia asiatica Linstow, 1901 (Cestoda, Cyclophyllidea, davaineidae). The older species was transferred in 1926 to the genus RaillietinaFuhrmann, 1920 (Cestoda, Cyclophyllidea, davaineidae), giving rise to the currently prevailing combination Raillietina asiatica (Linstow, 1901), and neither species has ever been considered congeneric with the other. Taenia asiaticaEom & Rim, 1993 is a widespread species with a substantial literature. Conservation of this name would do much more to avoid confusion in the medical and/or veterinary fields concerning this important human parasite than the alternative, i.e., introducing a new replacement name. [ABSTRACT FROM AUTHOR]

Copyright of Veterinarski Glasnik is the property of Veterinarski Glasnik and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Our knowledge of parasites in wildlife remains limited, primarily due to restricted access to samples, especially of parasites from protected species. This present study contributes to the comprehension of the enigmatic world of helminths of African wild mammals and cestode biodiversity by combining both molecular and morphological analysis. Cestode samples were opportunistically collected from 77 individual definitive hosts in South Africa, Namibia and Ethiopia, encompassing 15 different species of wild African carnivores and additionally domestic cats. The analysis revealed 32 different cyclophyllidean species of which 21 (65.6 %) represent previously unknown genetic entities. They belong to the families Mesocestoididae, Hymenolepididae, Dipylidiidae and Taeniidae. Here we cover the non-taeniid cestodes, while the taeniids will be addressed in a separate publication. Three of the non-taeniid species uncovered in this study could be assigned to the genus Mesocestoides and were isolated from servals and domestic cats. The white-tailed mongoose was found to be a suitable host for a species belonging to the Hymenolepididae, which was identified as Pseudandrya cf. mkuzii. Both feline and canine genotypes of Dipylidium caninum were detected in domestic cats, the canine genotype also in an African wolf. In addition to these, a novel species of Dipylidium was discovered in an aardwolf. Lastly, four distinct species of Joyeuxiella were found in this study, revealing a cryptic species complex and emphasizing the need for a taxonomic reassessment of this genus. Despite the limited scope of our study in terms of geography and sample size, the results highlight that biodiversity of cestodes in African wild mammals is grossly under-researched and follow-up studies are urgently required, in particular linking morphology to gene sequences.

Simple Summary: Ultrastructural characters of spermiogenesis and the spermatozoon of the cestode Meggittina gerbilli, a parasite of gerbils in Tunisia, were studied using transmission electron microscopy. The type III model of spermiogenesis was observed. This model is mainly characterized by a proximodistal fusion of a single flagellum with a cytoplasmic extension. As for the sperm cell, spermatozoon type VI was observed, presenting a single axoneme, a periaxonemal sheath, crest-like bodies, twisted cortical microtubules, and a spiraled nucleus. The results show similarities between Meggittina gerbilli and other studied species within the Catenotaeniidae family. Ultrastructural characters of spermiogenesis and the mature spermatozoon of the cestode Meggittina gerbilli (Cyclophyllidea: Catenotaeniidae), a parasite of the Lesser Egyptian gerbil (Gerbillus gerbillus) and the North African gerbil (Gerbillus campestris) (Rodentia: Muridae) in the Djebel Dahar (South of Tunisia), were studied using transmission electron microscopy. The spermiogenesis of M. gerbilli is of Bâ and Marchand's type III, which is mainly characterized by a proximodistal fusion of a single flagellum with a cytoplasmic extension. In this catenotaeniid, the proximal fusion is preceded by a 90° rotation of the flagellum. The spermatozoon is a Levron et al. type VI, which presents a single axoneme with the 9 + '1' trepaxonematan pattern, a periaxonemal sheath, two crest-like bodies, twisted cortical microtubules, and a spiraled nucleus. The obtained results show similarities with the remaining studied catenotaeniids, namely Catenotaenia pusilla and Skrjabinotaenia lobata. The results are compared and discussed according to several characteristics found in the catenotaeniids and other studied cyclophyllideans. [ABSTRACT FROM AUTHOR]

The Eurasian lynx (Lynx) is a medium-sized wild cat species distributed throughout Eurasia. There has been no report on Taenia species (Cestoda: Cyclophyllidea) infecting this felid in China. In this study, 24 tapeworms were found in two Eurasian lynxes (#1 and #2) in Xinjiang Uygur Autonomous Region (XUAR), northwestern China. Based on the number, measurements and the shape of rostellar hooks, these tapeworms belong to two Taenia species. According to the number (n = 32) and length (185–194 μm) of small hooks, the first Taenia species (n = 1, found in #2 lynx) was identified as Taenia laticollis. Phylogenetically, this species was clustered with T. laticollis genotype C (JX860623) based on its cytochrome c oxidase subunit 1 (cox1) and 16S rDNA sequences. The second Taenia species (n = 23, provisionally named as “Taenia sp.“) may represent a potentially novel tapeworm species, because of its obvious differences in the shape and lengths (174–182 μm, 98–113 μm) of large and small rostellar hooks in comparison with ten taxonomically related species. Molecular and phylogenetic analyses of the cox1 gene revealed that “Taenia sp.” has the highest rate of sequence identity (92.93%, 368/396 bp) with Taenia hydatigena reported from sheep (Ovis aries) in Slovakia. To sum up, a potentially novel tapeworm species, “Taenia sp.“, is found in Eurasian lynx. In addition, T. laticollis was found for the first time in China.

In this study, 263 tapeworms were collected from eight road-killed red foxes in Xinjiang Uygur Autonomous Region (XUAR, northwestern China). The tapeworms were analyzed based on morphological characters and mitochondrial cytochrome c oxidase subunit 1 (cox1) gene sequences. Eighty-three Taenia and 180 Mesocestoides tapeworms were identified according to the presence or absence of rostellum, and the number, the length and the shape of the large rostellar hooks. The morphological and molecular analyses revealed that i) 180 Mesocestoides tapeworms, here named as Mesocestoides sp. (Vulpes vulpes), showed 99.21% (378/381 bp) identity to Mesocestoides sp. reported from red fox in Mongolia; and ii) 83 Taenia tapeworms belonged to three species. The first Taenia species [n = 16, named as Taenia sp. (Vulpes vulpes)], based on the length of large rostellar hooks (337–342 μm) and its cox1 sequence, was identified as a potentially novel species, which is phylogenetically close to Taenia laticollis. The second species [n = 54, named as Taenia sp. (Vulpes vulpes & Rhombomys opimus)], was morphologically similar to Taenia endothoracicus according to the number (n = 52), the length (319–332 μm) and the shape of the large rostellar hooks. This species, infecting three red foxes, shared 100% cox1 sequence identity with Taenia sp. (Rhombomys opimus) genotype C found previously in great gerbils (Rhombomys opimus) in the same region. The third species (n = 13, named as Taenia polyacantha-like), had shorter large rostellar hooks (178–180 μm) and showed 96.27% (361/375 bp) sequence identity to Taenia polyacantha reported from red fox in Italy. The “great gerbil-red fox” life cycle of Taenia sp. (Vulpes vulpes & Rhombomys opimus), belonging to the mitochondrial lineage of T. endothoracicus, is confirmed. The T. polyacantha-like species was firstly found in red fox in China. Taenia sp. (Vulpes vulpes) is a potentially novel species, which is close to T. laticollis based on its phylogenetic properties.

Our knowledge of parasites in wildlife remains limited, primarily due to restricted access to samples, especially of parasites from protected species. This present study contributes to the comprehension of the enigmatic world of helminths of African wild mammals and cestode biodiversity by combining both molecular and morphological analysis. Cestode samples were opportunistically collected from 77 individual definitive hosts in South Africa, Namibia and Ethiopia, encompassing 15 different species of wild African carnivores and additionally domestic cats. The analysis revealed 32 different cyclophyllidean species of which 21 (65.6 %) represent previously unknown genetic entities. They belong to the families Mesocestoididae, Hymenolepididae, Dipylidiidae and Taeniidae. Here we cover the non-taeniid cestodes, while the taeniids will be addressed in a separate publication. Three of the non-taeniid species uncovered in this study could be assigned to the genus Mesocestoides and were isolated from servals and domestic cats. The white-tailed mongoose was found to be a suitable host for a species belonging to the Hymenolepididae, which was identified as Pseudandrya cf. mkuzii. Both feline and canine genotypes of Dipylidium caninum were detected in domestic cats, the canine genotype also in an African wolf. In addition to these, a novel species of Dipylidium was discovered in an aardwolf. Lastly, four distinct species of Joyeuxiella were found in this study, revealing a cryptic species complex and emphasizing the need for a taxonomic reassessment of this genus. Despite the limited scope of our study in terms of geography and sample size, the results highlight that biodiversity of cestodes in African wild mammals is grossly under-researched and follow-up studies are urgently required, in particular linking morphology to gene sequences. [Display omitted] • 77 definitive hosts belonging to 16 species of African carnivores were examined. • Phylogenetic and morphological methods were used for cestode identification. • 65.6% of cestode species found in African wild carnivores are genetically novel. • Detected species belong to Mesocestoides , Joyeuxiella , Dipylidium and Pseudandrya. • Phylogenetic analysis of Joyeuxiella genus revealed cryptic species complex. [ABSTRACT FROM AUTHOR]

The Cyclophyllidea comprises the most species-rich order of tapeworms (Platyhelminthes, Cestoda) and includes species with some of the most severe health impact on wildlife, livestock, and humans. We collected seven Cyclophyllidea specimens from rodents in Qinghai-Tibet Plateau (QTP) and its surrounding mountain systems, of which four specimens in QTP were unsequenced, representing "putative new species." Their complete mitochondrial (mt) genomes were sequenced and annotated. Phylogenetic reconstruction of partial 28S rDNA, cox 1 and nad 1 datasets provided high bootstrap frequency support for the categorization of three "putative new species," assigning each, respectively, to the genera Mesocestoides , Paranoplocephala , and Mosgovoyia , and revealing that some species and families in these three datasets, which contain 291 species from nine families, may require taxonomic revision. The partial 18S rDNA phylogeny of 29 species from Taeniidae provided high bootstrap frequency support for the categorization of the "putative new species" in the genus Hydatigera. Combined with the current investigation, the other three known Taeniidae species found in this study were Taenia caixuepengi , T. crassiceps , and Versteria mustelae and may be widely distributed in western China. Estimates of divergence time based on cox 1 + nad 1 fragment and mt protein-coding genes (PCGs) showed that the differentiation rate of Cyclophyllidea species was strongly associated with the rate of change in the biogeographic scenarios, likely caused by the uplift of the QTP; i.e., species differentiation of Cyclophyllidea might be driven by host-parasite co-evolution caused by the uplift of QTP. We propose an "out of QTP" hypothesis for the radiation of these cyclophyllidean tapeworms. [ABSTRACT FROM AUTHOR]

The Cyclophyllidea comprises the most species-rich order of tapeworms (Platyhelminthes, Cestoda) and includes species with some of the most severe health impact on wildlife, livestock, and humans. We collected seven Cyclophyllidea specimens from rodents in Qinghai-Tibet Plateau (QTP) and its surrounding mountain systems, of which four specimens in QTP were unsequenced, representing “putative new species.” Their complete mitochondrial (mt) genomes were sequenced and annotated. Phylogenetic reconstruction of partial 28S rDNA, cox1 and nad1 datasets provided high bootstrap frequency support for the categorization of three “putative new species,” assigning each, respectively, to the genera Mesocestoides, Paranoplocephala, and Mosgovoyia, and revealing that some species and families in these three datasets, which contain 291 species from nine families, may require taxonomic revision. The partial 18S rDNA phylogeny of 29 species from Taeniidae provided high bootstrap frequency support for the categorization of the “putative new species” in the genus Hydatigera. Combined with the current investigation, the other three known Taeniidae species found in this study were Taenia caixuepengi, T. crassiceps, and Versteria mustelae and may be widely distributed in western China. Estimates of divergence time based on cox1 + nad1 fragment and mt protein-coding genes (PCGs) showed that the differentiation rate of Cyclophyllidea species was strongly associated with the rate of change in the biogeographic scenarios, likely caused by the uplift of the QTP; i.e., species differentiation of Cyclophyllidea might be driven by host-parasite co-evolution caused by the uplift of QTP. We propose an “out of QTP” hypothesis for the radiation of these cyclophyllidean tapeworms.

In this study, 263 tapeworms were collected from eight road-killed red foxes in Xinjiang Uygur Autonomous Region (XUAR, northwestern China). The tapeworms were analyzed based on morphological characters and mitochondrial cytochrome c oxidase subunit 1 (cox1) gene sequences. Eighty-three Taenia and 180 Mesocestoides tapeworms were identified according to the presence or absence of rostellum, and the number, the length and the shape of the large rostellar hooks. The morphological and molecular analyses revealed that i) 180 Mesocestoides tapeworms, here named as Mesocestoides sp. (Vulpes vulpes), showed 99.21% (378/381 bp) identity to Mesocestoides sp. reported from red fox in Mongolia; and ii) 83 Taenia tapeworms belonged to three species. The first Taenia species [n = 16, named as Taenia sp. (Vulpes vulpes)], based on the length of large rostellar hooks (337–342 μm) and its cox1 sequence, was identified as a potentially novel species, which is phylogenetically close to Taenia laticollis. The second species [n = 54, named as Taenia sp. (Vulpes vulpes & Rhombomys opimus)], was morphologically similar to Taenia endothoracicus according to the number (n = 52), the length (319–332 μm) and the shape of the large rostellar hooks. This species, infecting three red foxes, shared 100% cox1 sequence identity with Taenia sp. (Rhombomys opimus) genotype C found previously in great gerbils (Rhombomys opimus) in the same region. The third species (n = 13, named as Taenia polyacantha -like), had shorter large rostellar hooks (178–180 μm) and showed 96.27% (361/375 bp) sequence identity to Taenia polyacantha reported from red fox in Italy. The "great gerbil-red fox" life cycle of Taenia sp. (Vulpes vulpes & Rhombomys opimus), belonging to the mitochondrial lineage of T. endothoracicus , is confirmed. The T. polyacantha -like species was firstly found in red fox in China. Taenia sp. (Vulpes vulpes) is a potentially novel species, which is close to T. laticollis based on its phylogenetic properties. [Display omitted] • The life cycle of Taenia sp. (Vulpes vulpes & Rhombomys opimus) is confirmed. • The Taenia polyacantha -like species was firstly found in China. • Taenia sp. (Vulpes vulpes) is a potentially novel species in China. [ABSTRACT FROM AUTHOR]

The Eurasian lynx (Lynx) is a medium-sized wild cat species distributed throughout Eurasia. There has been no report on Taenia species (Cestoda: Cyclophyllidea) infecting this felid in China. In this study, 24 tapeworms were found in two Eurasian lynxes (#1 and #2) in Xinjiang Uygur Autonomous Region (XUAR), northwestern China. Based on the number, measurements and the shape of rostellar hooks, these tapeworms belong to two Taenia species. According to the number (n = 32) and length (185–194 μm) of small hooks, the first Taenia species (n = 1, found in #2 lynx) was identified as Taenia laticollis. Phylogenetically, this species was clustered with T. laticollis genotype C (JX860623) based on its cytochrome c oxidase subunit 1 (cox1) and 16S r DNA sequences. The second Taenia species (n = 23, provisionally named as " Taenia sp.") may represent a potentially novel tapeworm species, because of its obvious differences in the shape and lengths (174–182 μm, 98–113 μm) of large and small rostellar hooks in comparison with ten taxonomically related species. Molecular and phylogenetic analyses of the cox1 gene revealed that " Taenia sp." has the highest rate of sequence identity (92.93%, 368/396 bp) with Taenia hydatigena reported from sheep (Ovis aries) in Slovakia. To sum up, a potentially novel tapeworm species, " Taenia sp.", is found in Eurasian lynx. In addition, T. laticollis was found for the first time in China. [Display omitted] • Taenia. laticollis was found for the first time in China. • " Taenia sp." is a potential novel tapeworm species found in Eurasian lynx. • Pairwise comparisons of the shape of the large rostellar hooks in Taenia sp. and the related species. [ABSTRACT FROM AUTHOR]

Copyright of Parasite (1252607X) is the property of EDP Sciences and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

• Adult cyclophyllidean tapeworms are reported from fish for the first known time. • We provide a unique example of host switching from birds to freshwater fish in Africa. • There is a common occurrence in six species of elephantfishes throughout Africa. • Molecular data indicate relatedness with dilepidid tapeworms from swifts in Africa. Tapeworms (Cestoda) of the order Cyclophyllidea include over 3,000 species of intestinal parasites of tetrapods, especially birds and mammals including humans. However, adults of cyclophyllideans have never been found in bony fishes, even though hundreds of thousands of these hosts have been examined for parasites globally over more than 250 years. In the present paper, we report on a unique example of host switching of a tapeworm from birds to teleost fish in Africa. A new genus, Ichthyolepis (Cyclophyllidea: Dilepididae), is erected to accommodate Ichthyolepis africana n. sp., which is the first cyclophyllidean tapeworm that sexually matures in teleost fishes. The new species parasitises several freshwater elephantfishes (Mormyriformes: Mormyridae) including Marcusenius macrolepidotus (type host) in South Africa, Marcusenius senegalensis in Senegal, Mormyrus caschive , M. niloticus and Pollimyrus isodori in the Sudan, and Mormyrus kannume in Egypt. Ichthyolepis n. gen. is typified by a large musculo-glandular apical apparatus with rostellar pouch and a rostellum armed with robust hooks similar in size, but different in shape, deep, sandglass-shaped genital atrium, vaginal atrium and cirrus armed with tiny spines, thick-walled, subspherical cirrus sac, large, lobulated ovary occupying a large part of the median pre-equatorial field of mature proglottids, numerous testes filling almost entirely the postequatorial median field of proglottids, long and narrow, sleeve-like lateral uterine diverticula, and spindle-shaped eggs. Molecular phylogenetics considers Ichthyolepis as a member of the lineage consisting of dilepidids from swifts (Apodidae) in Africa. All fish hosts of the new tapeworm are bottom feeders, live in muddy biotopes and are insectivorous, which indicates that its intermediate hosts may be insect larvae. [ABSTRACT FROM AUTHOR]

As training in helminthology has declined in the medical microbiology curriculum, many rare species of zoonotic cestodes have fallen into obscurity. Even among specialist practitioners, knowledge of human intestinal cestode infections is often limited to three genera, Taenia, Hymenolepis and Dibothriocephalus. However, five genera of uncommonly encountered zoonotic Cyclophyllidea (Bertiella, Dipylidium, Raillietina, Inermicapsifer and Mesocestoides) may also cause patent intestinal infections in humans worldwide. Due to the limited availability of summarized and taxonomically accurate data, such cases may present a diagnostic dilemma to clinicians and laboratories alike. In this review, historical literature on these cestodes is synthesized and knowledge gaps are highlighted. Clinically relevant taxonomy, nomenclature, life cycles, morphology of human-infecting species are discussed and clarified, along with the clinical presentation, diagnostic features and molecular advances, where available. Due to the limited awareness of these agents and identifying features, it is difficult to assess the true incidence of these 'forgotten' cestodiases as clinical misidentifications are likely to occur. Also, the taxonomic status of many of the human-infecting species of these tapeworms is unclear, hampering accurate species identification. Further studies combining molecular data and morphological observations are necessary to resolve these long-standing taxonomic issues and to elucidate other unknown aspects of transmission and ecology. [ABSTRACT FROM AUTHOR]

Abstract The taxonomic concept for the family Paruterinidae is controversial, especially concerning the position of the genus Cladotaenia , since the latter genus has been placed sometimes in other families, i.e. in the Taeniidae or in the distinct family Cladotaeniidae; finding a solution based on morphological data is difficult and molecular data on paruterinids and related groups are scarce. In this study, the complete mitochondrial (mt) genome sequence of the type-species of the type-genus of the Paruterinidae, Paruterina candelabraria , was determined and annotated. Gene arrangements are identical with those of Cladotaenia vulturi but differing from those of species of the family Taeniidae by the order change between tRNA-SerUCN and tRNA-LeuCUN. Phylogenetic tree was constructed by Bayesian Inference (BI) analysis using the concatenated amino acid sequences of 12 protein-coding genes. The analysis clearly shows that the Paruterinidae and Taeniidae are sister-groups, and Cladotaenia is a sister taxon of Paruterina. This supports the position of the genus Cladotaenia in the family Paruterinidae and reveals the necessity for sequencing additional taxa of the Paruterinidae for better understanding of phylogenetic relationships within the group. [ABSTRACT FROM AUTHOR]

The aims of the study are to enrich the partial 28S rDNA dataset for hymenolepidids by adding new sequences for species parasitic in the genera Sorex, Neomys and Crocidura (Soricidae) and to propose a new hypothesis for the relationships among mammalian hymenolepidids. New sequences were obtained for Coronacanthus integrus, C. magnihamatus, C. omissus, C. vassilevi, Ditestolepis diaphana, Lineolepis scutigera, Spasskylepis ovaluteri, Staphylocystis tiara, S. furcata, S. uncinata, Vaucherilepis trichophorus and Neoskrjabinolepis sp. The phylogenetic analysis (based on 56 taxa) confirmed the major clades identified by Haukisalmi et al. (Zool Scr 39:631-641, 2010) based on analysis of 31 species: Ditestolepis clade, Hymenolepis clade, Rodentolepis clade and Arostrilepis clade; however, the support was weak for the early divergent lineages of the tree and for the Arostrilepis clade. Novelties revealed include the molecular evidence for the monophyly of Coronacanthus, the non-monophyletic status of Staphylocystis and the polyphyly of Staphylocystoides. The analysis has confirmed the monophyly of Hymenolepis, the monophyly of hymenolepidids from glirids, the position of Pararodentolepis and Nomadolepis as sister taxa, the polyphyly of Rodentolepis, the position of Neoskrjabinolepis and Lineolepis as sister taxa, and the close relationship among the genera with the entire reduction of rostellar apparatus. Resolved monophyletic groups are supported by the structure of the rostellar apparatus. The diversification of the Ditestolepis clade is associated with soricids. The composition of the other major clades suggests multiple evolutionary events of host switching, including between different host orders. The life cycles of Coronacanthus and Vaucherilepis are recognised as secondarily aquatic as these taxa are nested in terrestrial groups. [ABSTRACT FROM AUTHOR]

Free pre-tetrathyridia of Mesocestoides sp. are described, for the first time, from samples obtained from the coelomic cavity of a ground skink, Scincella lateralis, from Oklahoma. Closer examination of these early-stage tapeworms revealed they were transitional metamorphosis stages between a post-hexacanth procercoid form to the full metacestode of Mesocestoides. A series of transitional stages was found that span the full period of sucker and apical organ development. However, we did not see any fully developed tetrathyridia, i.e., having classic Mesocestoides morphology but with the apical sucker absent following developmental atrophy. This is the first time that metamorphic pre-tetrathyridial stages of a Mesocestoides sp. have been reported in vivo from a natural infection. These observations corroborate earlier reports of such stages of Mesocestoides vogae developed in vitro, though the previously reported isolate of M. vogae is asexually proliferative, and the species from the present study showed no sign of asexual proliferation. The fact that these immediately post-hexacanth stages can occur in a single lizard intermediate host may suggest that Mesocestoides spp. might develop through a simple 2-host life cycle rather than an obligate 3-host cycle that has been speculated to occur by most previous authors. DNA sequence comparisons and phylogenetic analyses based on mitochondrial 12S, cox1, and nad1 genes have demonstrated that our specimens from S. lateralis represent a species clearly distinct from all previously sequenced Mesocestoides and closely related to 2 forms from domestic dogs and Channel Island fox in California previously published as Mesocestoides sp. C. [ABSTRACT FROM AUTHOR]

Both the oncospheral tegument and the hook region membrane (HRM) of Echinococcus multilocularis hexacanths originate from a syncytial binucleate complex that appears in the early stage of morphogenesis and organogenesis of the hexacanth larva. The primordium of this binucleate complex forms a binucleate syncytial cap or “calotte” situated beneath the inner envelope at one pole of the developing embryo. During oncospheral differentiation, the binucleate perikaryon of the syncytial cap is sunk progressively deeper into the central part of the embryo, but remains always connected with the distal cytoplasm by a tendrillar cytoplasmic connection or bridge. Following migration or sinking of the binucleate perikaryon, numerous cytoplasmic vesicles appear in the distal cytoplasm. These vesicles fuse progressively together and form a single large cavity or lacuna. The walls of this cavity are becoming at this point the walls of two delaminated layers: (1) the distal anucleated cytoplasmic layer is transformed into the oncospheral tegument and (2) the proximal thin cytoplasmic layer is transformed into the “hook region membrane”. This delamination of the initially compact layer of distal cytoplasm into two layers seems to be closely associated with differentiation of oncospheral hooks, the elongating blades of which protrude progressively into a newly formed cavity. The pressure of hook blades on the hook region membrane appears to facilitate its further separation from the basal layer of distal cytoplasm which is transformed into the peripheral layer of oncospheral tegument. In the mature oncosphere, the surface of this peripheral layer forms a regular brush border of cytoplasmic processes or microvilli and represents the true body covering of the hexacanth. The very thin cytoplasmic connection between the peripheral layer of tegument and binucleate perikaryon appears only very seldom in the ultrathin sections as a narrow cytoplasmic strand and has a plasma membrane that is reinforced by a single row of cortical microtubules. The HRM covers only one pole of the oncosphere and is attached to the oncosphere surface. The HRM is clearly visible in the mature oncosphere and is draped over the hook blades, the sharp points of which are protected by moderately electron-dense caps. Comparison of the above morphology with that of TEM study of the tegument of adult cestodes shows a great similarity as well as homology in the body covering of both larval and adult cestodes. [ABSTRACT FROM AUTHOR]

The cestode Hymenolepis microps is an intestinal parasite of tetraonid birds, including the willow ptarmigan (Lagopus lagopus). This parasite is able to maintain a high prevalence and intensity throughout the year, even in a subarctic environment in bird populations with relatively low host densities, indicating effective transmission routes. Willow ptarmigan consume mainly vegetal material and active consumption of invertebrates is confined to the first two or three weeks of life. Ptarmigan are infected by different species of ectoparasites, of which two species of feather lice, Lagopoecus affinis and Goniodes lagopi, are the most abundant. In this study, we explored the hypothesis that feather lice may be suitable intermediate hosts for H. microps. We applied histological techniques and light microscopy to investigate lice for the presence of larval cestode stages (cysticercoids). We found 12 cysticercoid-like structures inside chewing lice collected on L. lagopus hosts harbouring H. microps. In addition, a polymerase chain reaction (PCR) screening of Ischnocera lice DNA, targeting the 18S rRNA gene of the cestode, showed positive results for two different short fragments of the 18S rRNA gene of H. microps which were sequenced from lice collected on birds. Both independent lines of evidence support the hypothesis that Ischnocera lice might be suitable intermediate hosts in the life cycle of H. microps in L. lagopus. [ABSTRACT FROM AUTHOR]

This article reviews the primary results of a taxonomic revision of species of the genus Aploparaksis Clerc, 1903 (Cestoda: Cyclophyllidea: Aploparaksidae), which are widespread parasites of birds. We consolidate a deep, primarily Russian, literature that has not been easily accessible, including insights from the recent monograph of Bondarenko & Kontrimavichus (2006a). A revision of Aploparaksis has been based on an extensive review of the literature and on the study of diverse specimens from the Palearctic (Lithuania, European and Asian parts of Russia) and the Nearctic (Alaska) regions assembled from our field collections. We also conducted the re-examination of type and voucher specimens from various museums and institutions in Russia, Europe, and the USA, and material from the personal collections of several scientists. Taxonomic conclusions in the revision combine observations of morphological characters for adults and data regarding metacestode ontogeny and life cycles of 36 species of Aploparaksis. The validity of 58 species of Aploparaksis among the 102 described is confirmed. Summaries for each valid species include: taxonomic synonyms, a range of both definitive and intermediate hosts (if known), site within the hosts, geographical distributions, morphological modifications of the cysticercoid, and a short specific diagnosis with illustrations of the principal characteristics. Collection numbers of specimens deposited in museums are provided for each species. Within the genus, two phylogenetic lineages differing in the topography of female gonads have been recognized: the nominotypical subgenus Aploparaksis (Aploparaksis) Clerc, 1903, with the female gonads arranged along the longitudinal axis of the proglottid, and Aploparaksis (Tanureria) Spassky et Yurpalova, 1968, with the female gonads disposed in a transverse row in the median field of the proglottid. Diagnoses of subgenera and identification keys to their species are presented. A list of invalid species with brief comments regarding each of them is also given. The taxonomic value of ontogenetic features and complex issues concerning the definition of Aploparaksis are discussed. [ABSTRACT FROM AUTHOR]

Raillietina celebensis is a cestode that parasitizes the small intestine of rats and humans. Here, we detail the morphology and morphometry of R. celebensis based on specimens collected from Rattus norvegicus in the municipality of São Gonçalo, state of Rio de Janeiro, Brazil, by light and confocal scanning laser microscopies and also report the results of molecular phylogenetic analyses to determine its relationships within the family Davaineidae. Analysis of the number and size of testes, number and shape of rostellar hooks, cirrus sac length, capsules and eggs per capsule, and morphology of the mature proglottid allowed concluding that the present specimens constitute a new record of R. celebensis in South America. Our genetic and phylogenetic analyses, based on the partial small subunit 18S rRNA gene, revealed R. celebensis to be in the family Davaineidae within the genus Raillietina, in agreement with the morphological taxonomy. Phylogenetic trees obtained by neighbor-joining and maximum likelihood methods demonstrated R. celebensis as a unique taxonomic unit, and also demonstrated some taxonomic inconsistences. The incorporation of Brazilian R. celebensis sequences derived from mammals in the phylogeny of davaineids is consistent with the assertion that neither Raillietina nor Fuhrmannetta can be supported as distinct genera. [ABSTRACT FROM AUTHOR]

From 1999 through 2012, a total of 541 individual rodents (jerboas of the family Dipodidae) were collected from several habitat types, primarily from the Gobi region of Mongolia, and were examined for helminth and protistan parasites. Of those rodents, 25 were identified as Pygeretmus pumilio Kerr, 1792 (Rodentia: Dipodidae), whereas 516 were other species of jerboa from the provinces of Dornogobi, Dundgobi, Omnogobi, Ovorhangai, Bayanhongor, Gobi Altai, and Hovd. During our field work, we collected several cestodes; some of which represented undescribed species, and these new species occurred in 40% of P. pumilio from four separate collecting localities. We designate this new species as Catenotaenia tuyae n. sp. (Cyclophyllidea: Catenotaeniidae), which is characterized by having relatively long and narrow gravid proglottids and an ovary in mature segments that is located antiporally in the anterior portion of the mature proglottids. In addition, the position and the ratio of the genital pore toward the anterior end of the proglottids are unique and the ovary is elongate, being confined to the antiporal part of the mature proglottid. These morphological features serve to differentiate Catenotaenia tuyae from all other species in the genus included in the phylogenetic analysis and are supported by molecular phylogenetic evidence using the 28S ribosomal RNA gene. The intensity of C. tuyae infection in Pygeretmus ranged from 1 to 3 individual cestodes per infected host. [ABSTRACT FROM AUTHOR]

A new species of cyclophyllidean tapeworm, Oochoristica harschi sp. nov. is described from 2 of 18 (11%) non-native Mediterranean geckos (Hemidactylus turcicus) collected in June 2016 from Tom Green County, Texas, USA The new species has few characteristics in common with 17 species of Oochoristica previously described from Nearctic reptiles. Of this group, O. harschi is most similar to O. macallisteri Bursey and Goldberg, 1996 from the side-blotched lizard, Uta stansburiana from Arizona and California, USA, in number of testes, 14-20 vs. 12-20. However, O. harschi has oval suckers and a long neck compared to the circular suckers and absent neck in O. macallisteri. On comparison with other species of Oochoristica, it was found O. chinensis Jensen, Schmidt and Kuntz, 1983 from the Sino-Japanese realm, O. iguanae Bursey and Goldberg, 1996 from the Neotropical realm, and O. maccoyi Bursey and Goldberg, 1966 from the Panamanian realm were most similar to the new species. However, O. harschi can be differentiated by possessing a much longer neck and a shorter cirrus pouch. It can be further differentiated from O. chinensis by possessing an ovoid vs. an irregular vitellarium, from O. iguanae by having a smaller strobilus (65 vs. 110 mm) as well as an ovoid vs. a triangular vitellarium, and from O. maccoyi by having significantly more proglottids (145 vs. 89) and a longer strobilus (65 vs. 20 mm). The new species is the fifth species of Oochoristica reported from non-native H. turcicus and the 18th species described from the Nearctic region. [ABSTRACT FROM AUTHOR]

Background: Taenia saginata is a tapeworm found in cattle worldwide. Analysis of genetic diversity in different geographical populations of T. saginata not only helps to understand the origin, transmission and spread of this organism, but also to evaluate the selection pressures acting on T. saginata and how it is responding to them. However, there are few reports of the genetic variability of T. saginata populations in different regions of the world, including Lao PDR and Thailand. We report the genetic diversity of T. saginata populations in Lao PDR and northeastern Thailand together with sequences of T. saginata from other countries deposited in GenBank. Results: Mitochondrial cox1 sequence analysis revealed that 15 and 8 haplotypes were identified in 30 and 21 T. saginata isolates from Lao PDR and northeastern Thailand, respectively. Fifty-three haplotypes were identified from 98 sequences. Phylogenetic tree and haplotype network analyses revealed that global isolates of T. saginata were genetically divided into five groups (A, B, C1, C2 and D). Taenia saginata isolates from Lao PDR and northeastern Thailand belonged to either Group A or B. Taenia saginata from western Thailand clustered in groups C1, C2 and D, and populations from the northeast and western Thailand were found to be genetically distinct. Taenia saginata isolates in Lao PDR and Thailand were also found to be genetically diverse but the degree of genetic differentiation was low. Conclusions: Taenia saginata populations from Lao PDR and northeastern Thailand are genetically distinct from the population in western Thailand and it is proposed that T. saginata has been dispersed by different transmission routes in Southeast Asia. [ABSTRACT FROM AUTHOR]

The main purpose of this study was to characterize the helmintological fauna of three commensal rodents from Argentina, with the final goal of finding Strobilocercus fasciolaris (Cestoda: Cyclophyllidea), discussing possible reasons of the maintenance of the cycle in the study areas. Strobilocercus fasciolaris was observed in all the studied rodent species, including Rattus rattus and Mus musculus, which constitute new host records in Argentina. Estimates of prevalence, mean abundance and mean intensity were provided, and the existing morphometric characterization of the parasite was supplemented. Significant differences of prevalence between R. norvegicus and M. musculus and among seasons were observed. The potential risk of zoonotic transmission of S. fasciolaris is suggested. [ABSTRACT FROM AUTHOR]

The present study provides the first ultrastructural data of the vitellogenesis in a cestode species of the cyclophyllidean family Paruterinidae, aiming to expand the limited data on the vitellogenesis in cyclophyllidean cestodes and to explore the potential of ultrastructural characters associated with vitellogenesis for phylogenetic and taxonomic studies of this order. The process of vitellocyte formation in Dictyterina cholodkowskii follows the general pattern observed in other tapeworms but exhibits several specific differences in the ultrastructure of vitelline cells. The vitellarium contains vitellocytes at various stages of maturation. The periphery of the vitellarium and the space between maturing vitellocytes are occupied by interstitial cells. Differentiation into mature vitellocytes is characterized by high secretory activity, which involves the development of granular endoplasmic reticulum, Golgi complexes, mitochondria and vitelline globules of various sizes. During vitellogenesis, the progressive fusion of these globules results in the formation of two large membrane-limited vitelline vesicles that eventually fuse into a single large vesicle. Mature vitellocytes are composed of a single vitelline vesicle, a high content of cytoplasmic organelles and have no nucleus. No traces of lipid droplets and glycogen granules are detected in the cytoplasm of mature vitellocytes, which might be related to biological peculiarities of this family, i.e. the release of eggs into environment within the tissues of the paruterine organ, which may serve as a source of nutrients for embryos. [ABSTRACT FROM AUTHOR]

We characterised the causative agents of cerebral and non-cerebral coenurosis in livestock by determining the mitochondrial genotypes and morphological phenotypes of 52 Taenia multiceps isolates from a wide geographical range in Europe, Africa, and western Asia. Three studies were conducted: (1) a morphological comparison of the rostellar hooks of cerebral and non-cerebral cysts of sheep and goats, (2) a morphological comparison of adult worms experimentally produced in dogs, and (3) a molecular analysis of three partial mitochondrial genes ( nad1, cox1, and 12S rRNA) of the same isolates. No significant morphological or genetic differences were associated with the species of the intermediate host. Adult parasites originating from cerebral and non-cerebral cysts differed morphologically, e.g. the shape of the small hooks and the distribution of the testes in the mature proglottids. The phylogenetic analysis of the mitochondrial haplotypes produced three distinct clusters: one cluster including both cerebral isolates from Greece and non-cerebral isolates from tropical and subtropical countries, and two clusters including cerebral isolates from Greece. The majority of the non-cerebral specimens clustered together but did not form a monophyletic group. No monophyletic groups were observed based on geography, although specimens from the same region tended to cluster. The clustering indicates high intraspecific diversity. The phylogenetic analysis suggests that all variants of T. multiceps can cause cerebral coenurosis in sheep (which may be the ancestral phenotype), and some variants, predominantly from one genetic cluster, acquired the additional capacity to produce non-cerebral forms in goats and more rarely in sheep. [ABSTRACT FROM AUTHOR]

Parasites of two small fish species from a Ramsar wetland in South Africa were studied in 2014–2015. The cichlidPseudocrenilabrus philander(Weber, 1897) was parasitised by the copepodLernaea cyprinaceaLinnaeus, 1758, the monogeneanGyrodactylus thlapiChristison, Shinn & van As, 2005 and four gryporhynchid metacestode (Cyclophyllidea) species:Paradilepis scolecina(Rudolph, 1819),Paradilepis malekiKhalil, 1961,Neogryporhynchus lasiopeiusBaer & Bona, 1960 andValipora campylancristrota(Wedl, 1855). The cyprinidEnteromius paludinosus(syn.Barbus paludinosus) (Peters, 1852) was infected with the monogenean parasitesDogielius intorquensCrafford, Luus-Powell & Avenant-Oldewage, 2012,Dactylogyrus teresaeMashego, 1983, and threeDactylogyrusspp. These results represent several new locality as well as host records and further contribute information on the parasitic diversity in the Barberspan Ramsar wetland. [ABSTRACT FROM PUBLISHER]

Given the widespread distribution and medical implication of members of the genus Hymenolepis, specific identification of the aetiological agent becomes imperative. For precise diagnosis of the species, molecular techniques such as PCR and RFLP of the nuclear ribosomal internal transcribed spacer 2 (rDNA-ITS2) gene marker were carried out. The results showed distinct restriction patterns for both Hymenolepis nana and Hymenolepis diminuta when digested with either of the enzymes RsaI, HaeIII or HhaI. The annotated rDNA-ITS2 sequences from the two species revealed differences in the length; the folded secondary structure also depicted clear demarcation between the two species with variations in length of the helices, pyrimidine-pyrimidine mismatches and sites where motifs occur. In phylogenetic analysis of the evolutionary relationship between the two species as well as with other members of the family Hymenolepididae, the species causing human hymenolepiasis were found to be distantly related as they diverged independently from the ancestral lineage. [ABSTRACT FROM AUTHOR]

ContextPlants and plant products have been used in traditional medicine as anthelmintic agents in human and veterinary medicine. Three species ofSennaplant,S. alata(L),S. alexandrina(M) andS. occidentalis(L.) Link (Fabaceae) have been shown to have a vermicidal/vermifugal effect on a zoonotic tapewormHymenolepis diminuta(Rudolphi) (Cyclophyllidean). ObjectiveThe present study validates the mode of action of theseSennaplants on the parasite. The alcoholic leaf extract was determined to obtain information on the intracellular free calcium concentration level. Materials and methodsHymenolepis diminutawas maintained in Sprague–Dawley rat model for 2 months. Live parasites collected from infected rat intestine were exposed to 40 mg/mL concentration of each plant extracts prepared in phosphate buffer saline at 37 °C, till parasite gets paralyzed. The rate of efflux of calcium from the parasite tissue to the medium and the level of intracellular Ca2+ concentration were determined by an atomic absorption spectroscopy. ResultsThis study revealed that exposure of the worms to the plant extract leads to disruption in intracellular calcium homeostasis. A significant increase (44.6% and 25%) of efflux in Ca2+ from the tissue to the incubated medium was observed.Senna alatashowed high rate of efflux (5.32 mg/g) followed byS. alexandriaandS. occidentalis(both 4.6 mg/g) compared with control (3.68 mg/g). Discussion and conclusionThese results suggest that leaf extracts caused membrane permeability to Ca2+ after vacuolization of the tegument under stress and the extracts may contain compound that can be used as a chemotherapeutic agent. [ABSTRACT FROM PUBLISHER]

The effects of plant-bound zinc (Zn) and cadmium (Cd) on element uptake and their interactions in a parasite-host system were investigated in a model experiment. Male Wistar rats were divided into four groups (C, P, TC and TP). Groups TC and TP were infected with the rat tapeworm Hymenolepis diminuta. Groups C and TC were fed a standard rodent mixture (ST-1) and received 10.5 mg of Zn per week, while groups P and TP were fed a mixture supplemented with the Zn- and Cd-hyperaccumulating plant Arabidopsis halleri at a dosage of 236 mg Zn/week and 3.0 mg Cd/week. Rats were euthanized after 6 weeks, and Cd and Zn levels were determined in rat and tapeworm tissue. The results indicate that tapeworm presence did have an effect on Cd and Zn concentrations in the host tissue; the majority of tissues in infected rats had statistically significant lower Zn and Cd concentrations than did uninfected rats. Tapeworms accumulated more zinc and cadmium than did the majority of host tissues. This important finding confirms the ability of tapeworms to accumulate certain elements (heavy metals) from the host body to their own body tissues. Thus, tapeworms can decrease heavy metal concentrations in host tissues. [ABSTRACT FROM AUTHOR]

Asexually proliferating Taenia crassiceps (Zeder, 1800) metacestodes isolated within past decades have been successfully sub-cultured under experimental conditions using Mus musculus Linnaeus, 1758 mice. However, during their development, morphological irregularities of scolex structures have been reported in two of the three strains of this cestode species maintained in mice – ORF and KBS. The main goal of this work is to describe the abnormalities observed in a sample of 118 cysticerci of the third T. crassiceps strain used at present – WFU. Morphological abnormalities were detected in 39.8% of the evaginated scoleces; they consisted of supernumerary suckers (n= 2), duplicated (n= 2) or absent rostellum (n= 1), as well as absent or aberrant (n= 29) hooks, which were significantly shorter when compared to the large and short hook lengths referred to in the literature. [ABSTRACT FROM AUTHOR]

The Cyclophyllidea is the most diverse order of tapeworms, encompassing species that infect all classes of terrestrial tetrapods including humans and domesticated animals. Available phylogenetic reconstructions based either on morphology or molecular data lack the resolution to allow scientists to either propose a solid taxonomy or infer evolutionary associations. Molecular markers available for the Cyclophyllidea mostly include ribosomal DNA and mitochondrial loci. In this study, we identified 3641 single-copy nuclear coding loci by comparing the genomes of Hymenolepis microstoma, Echinococcus granulosus and Taenia solium. We designed RNA baits based on the sequence of H. microstoma, and applied target enrichment and Illumina sequencing to test the utility of those baits to recover loci useful for phylogenetic analyses. We captured DNA from five species of tapeworms representing two families of cyclophyllideans. We obtained an average of 3284 (90%) of the targets from the test samples and then used captured sequences (2 181 361 bp in total; fragment size ranging from 301 to 6969 bp) to reconstruct a phylogeny for the five test species plus the three species for which genomic data are available. The results were consistent with the current consensus regarding cyclophyllidean relationships. To assess the potential for our method to yield informative genetic variation at intraspecific scales, we extracted 14 074 single nucleotide polymorphisms ( SNPs) from alignments of four Arostrilepis macrocirrosa and two A. cooki and successfully inferred their relationships. The results showed that our target gene tools yield data sets that provide robust inferences at a range of taxonomic scales in the Cyclophyllidea. [ABSTRACT FROM AUTHOR]

Order Cyclophyllidea (of cestode platyhelminths) has a rich diversity of parasites and includes many families and species that are known to cause serious medical condition in humans and domestic and wild animals. Despite various attempts to resolve phylogenetic relationships at the inter-family level, uncertainty remains. In order to add resolution to the existing phylogeny of the order, we generated partial mtCO1 sequences for some commonly occurring cyclophyllidean cestodes and combined them with available sequences from GenBank. Phylogeny was inferred taking a total 83 representative species spanning 8 families using Bayesian analysis. The phylogenetic tree revealed Dilepididae as the most basal taxon and showed early divergence in the phylogenetic tree. Paruterinidae, Taeniidae and Anoplocephalidae showed non-monophyletic assemblage; our result suggests that the family Paruterinidae may represent a polyphyletic group. The diverse family Taeniidae appeared in two separate clades; while one of them included all the members of the genus Echinococcus and also Versteria, the representatives of the genera Taenia and Hydatigera clubbed in the other clade. A close affinity of Dipylidiidae with Taenia and Hydatigera was seen, whereas existence of a close relationship between Mesocestoididae and Echinococcus (of Taeniidae) is also demonstrated. The crown group comprised the families Anoplocephalidae, Davaineidae, Hymenolepididae and Mesocestoididae, and also all species of the genus Echinococcus and Versteria mustelae; monophyly of these families (excepting Anolplocephalidae) and the genus Echinococcus as well as its sister-taxon relation with V. mustelae is also confirmed. Furthermore, non-monophyly of Anoplocephalidae is suggested to be correlated with divergence in the host selection. [ABSTRACT FROM AUTHOR]

Background: Tapeworms Cladotaenia spp. are among the most important wildlife pathogens in birds of prey. The genus Cladotaenia is placed in the family Paruterinidae based on morphological characteristics and hosts. However, limited molecular information is available for studying the phylogenetic position of this genus in relation to other cestodes. Methods: In this study, the complete mitochondrial (mt) genome of Cladotaenia vulturi was amplified using "Long-PCR" and then sequenced by primer walking. Sequence annotation and gene identification were performed by comparison with published flatworm mt genomes. The phylogenetic relationships of C. vulturi with other cestode species were established using the concatenated amino acid sequences of 12 protein-coding genes with Bayesian Inference and Maximum Likelihood methods. Results: The complete mitochondrial genome of the Cladotaenia vulturi is 13,411 kb in size and contains 36 genes. The gene arrangement of C. vulturi is identical to those in Anoplocephala spp. (Anoplocephalidae), Hymenolepis spp. (Hymenolepididae) and Dipylidium caninum (Dipylidiidae), but different from that in taeniids owing to the order shift between the tRNA (L1) and tRNA (S2) genes. Phylogenetic analyses based on the amino acid sequences of the concatenated 12 protein-coding genes showed that the species in the Taeniidae form a group and C. vulturi is a sister taxon to the species of the family Taeniidae. Conclusions: To our knowledge, the present study provides the first molecular data to support the early proposal from morphological evidence that the Taeniidae is a sister group to the family Paruterinidae. This novel mt genome sequence will be useful for further investigations into the population genetics, phylogenetics and systematics of the family Paruterinidae and inferring phylogenetic relationships among several lineages within the order Cyclophyllidea. [ABSTRACT FROM AUTHOR]

The mature spermatozoon of Thysanotaenia congolensis, an intestinal parasite of black rat Rattus rattus from Cape Verde, is described by means of transmission electron microscopy. The ultrastructural organization of the sperm cell of T. congolensis follows Levron et al.'s type VII of the Eucestoda. It corresponds to a uniflagellate spermatozoon that presents crested bodies, periaxonemal sheath and intracytoplasmic walls, spiralled cortical microtubules and nucleus spiralled around the axoneme. These characteristics are also present in the spermatozoa of other inermicapsiferines and differ from the characters found in species belonging to the remaining subfamilies of anoplocephalids, namely Anoplocephalinae, Linstowiinae and Thysanosomatinae. Several authors consider the family Anoplocephalidae as a polyphyletic group, and its relationships with the Davaineidae are a matter of controversy. The phylogenetic implications of spermatological ultrastructural features present in inermicapsiferines and in the remaining anoplocephalids are discussed, and the available data on anoplocephalids are compared to similar results in davaineids in order to contribute to a better knowledge of relationships between these cyclophyllidean families. [ABSTRACT FROM AUTHOR]

A new species of tapeworm, Taenia lynciscapreoli sp. n. (Cestoda, Cyclophyllidea), is described from the Eurasian lynx (Lynx lynx), the main definitive host, and the roe deer (Capreolus capreolus and C. pygargus), the main intermediate hosts, from Finland and Russia (Siberia and the Russian Far East). The new species was found once also in the wolf (Canis lupus) and the Eurasian elk/moose (Alces alces), representing accidental definitive and intermediate hosts, respectively. The conspecificity of adult specimens and metacestodes of T. lynciscapreoli sp. n. in various host species and regions, and their distinction from related species of Taenia, was confirmed by partial nucleotide sequences of the mitochondrial cytochrome c oxidase subunit 1 gene. Morphologically, T. lynciscapreoli sp. n. can be separated unambiguously from all other species of Taenia by the shape of its large rostellar hooks, particularly the characteristically short, wide and strongly curved blade. If the large rostellar hooks are missing, T. lynciscapreoli may be separated from related species by a combination of morphological features of mature proglottids. It is suggested that T. lynciscapreoli has been present in published materials concerning the tapeworms of L. lynx and L. pardinus in Europe, but has been misidentified as Taenia pisiformis (Bloch, 1780). Taenia lynciscapreoli sp. n. has not been found in lynx outside the range of roe deer, suggesting a transmission pathway based on a specific predator-prey relationship. The present study applies a novel, simple approach to compare qualitative interspecific differences in the shape of rostellar hooks. [ABSTRACT FROM AUTHOR]

Rodentolepis nana (syn. Hymenolepis nana) is a cyclophyllidean zoonotic enteric parasite with worldwide distribution. In humans, it is more prevalent in children, especially in temperate zones. A morphologically similar species of R. nana occurs in different rodents, including gerbils. In the present study molecular characterization of five isolates of R. nana from Rhombomys opimus in the Golestan Province (n= 2) and Razavi Khorasan Province (n= 3), both in north-eastern Iran, were analysed. After DNA extraction, the internal transcribed spacer 2 (ITS2) region of the R. nana isolates was amplified and sequenced, and genetic variation was analysed. Accordingly, two isolates from the Razavi Khorasan Province showed ITS2 signatures that differed from the isolates from the Golestan Province. The third isolate from Razavi Khorasan did not reveal these specific signatures, but exhibited sparse nucleotide polymorphisms in the ITS2 sequence. The ITS gene is conserved, and variation in this fragment could be an interesting subject for further inspection of existing variation in the genome of R. nana, among different domestic and wildlife host species and from different areas. [ABSTRACT FROM AUTHOR]

The functional ultrastructure of eggs and cellular organization of hexacanths from gravid proglottids of Thysanotaenia congolensis, from black rats from Cape Verde, were examined by transmission electron microscopy. Mature eggs with fully formed hexacanths are grouped within parenchymatous capsules of gravid proglottids. Oncospheral envelopes surrounding mature hexacanths are reduced to a very thin membranous embryophore as their protective function is taken over by the parenchymatous capsules originating from the medullary parenchyma of immature proglottids and composed of three layers. Six major cell types are present: a bi-nucleate medullary centre; a six-nucleate U-shaped penetration gland; a second type of penetration gland; two neurosecretory-type nerve cells; about 30 somatic cells; and about 12 germinative cells. Present results on the functional ultrastructure of eggs and cellular organization of hexacanths support the phylogenetic distinction between T. congolensis and cestodes of the subfamily Anoplocephalinae. [ABSTRACT FROM PUBLISHER]

Hymenolepis nana, commonly known as the dwarf tapeworm, is one of the most common tapeworms of humans and rodents and can cause hymenolepiasis. Although this zoonotic tapeworm is of socio-economic significance in many countries of the world, its genetics, systematics, epidemiology, and biology are poorly understood. In the present study, we sequenced and characterized the complete mitochondrial (mt) genome of H. nana. The mt genome is 13,764 bp in size and encodes 36 genes, including 12 protein-coding genes, 2 ribosomal RNA, and 22 transfer RNA genes. All genes are transcribed in the same direction. The gene order and genome content are completely identical with their congener Hymenolepis diminuta. Phylogenetic analyses based on concatenated amino acid sequences of 12 protein-coding genes by Bayesian inference, Maximum likelihood, and Maximum parsimony showed the division of class Cestoda into two orders, supported the monophylies of both the orders Cyclophyllidea and Pseudophyllidea. Analyses of mt genome sequences also support the monophylies of the three families Taeniidae, Hymenolepididae, and Diphyllobothriidae. This novel mt genome provides a useful genetic marker for studying the molecular epidemiology, systematics, and population genetics of the dwarf tapeworm and should have implications for the diagnosis, prevention, and control of hymenolepiasis in humans. [ABSTRACT FROM AUTHOR]

We describe Paranoplocephala yoccozi n. sp. (Cestoda: Anoplocephalidae) from the snow vole Chionomys nivalis in Bourg-Saint-Maurice, French Alps, compare it with several related species from rodents, and review the anoplocephalid cestodes of snow voles in Europe. Paranoplocephala yoccozi n. sp. is primarily distinguished from the related species by its large scolex of characteristic shape, robust neck region, and the structure of the cirrus sac, vitellarium and vagina. We show that the anoplocephalid cestodes of snow voles in Europe, representing the genera Anoplocephaloides and Paranoplocephala, include at least seven species. This fauna consists primarily of species that snow voles share with other voles inhabiting the high-mountain areas. Some of the species, including P. yoccozi n. sp., appear to have a very localized distribution, which is assumed to be a consequence of the historical fragmentation of snow vole populations.