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Rodentolepis nana (syn. Hymenolepis nana), the most common cyclophyllid tapeworm infecting rodents, is a well-studied gastrointestinal parasite in mice and belongs to the family Hymenolepididae. The present study focuses on the molecular analysis for the nuclear genes (ITS-1, 18 S, and 28 S rDNA) used for the accurate recognition of the recovered Rodentolepis species. The annotated partial ITS-1, 18 S, and 28 S rDNA gene regions were deposited in GenBank (gbǀ MW310394.1, gbǀ MW327585.1, and gbǀ MW324479.1, respectively) and further used in the maximum likelihood method (ML) to clarify their genetic relationships at the species level. The interrogation sequence of R. nana was aligned and belonged to the family Hymenolepididae, in the same group as all Hymenolepis species, which were distinct from Cyclophyllidea cestodes, especially species belonging to Anoplocephalidae and Taeniidae. Sequence data support the paraphyly of Hymenolepis species. The phylogeny supports the availability of the ITS-1, 18 S, and 28 S rDNA genes as reliable genetic markers for evolutionary relationships.

Despite the ubiquity of parasitism, the knowledge regarding fossil parasites remains fragmentary. As an example, South American clade Xenarthra was a predominant group of mammals during the Cenozoic; however, its paleoparasitological knowledge has many gaps, with only a few reports in armadillos and fewer in ground sloths. Darwin’s ground sloth (Mylodon darwini) was a mega mammal widely distributed in the Neotropics; however, its parasitic fauna is poorly known with the sole report of unidentified nematode eggs. Thus, this study aimed to determine additional host-parasite associations and to discuss its possible role as a reservoir of zoonotic parasites. Fifty-two coprolites from Cueva del Milodon Natural Monument were analyzed through coprological analysis to determine the presence of parasites. From these, 18 (34.62%) coprolites had parasitic helminth eggs belonging to 6 taxa: Calodium sp., Ascaridida, Hymenolepididae, Anoplocephalidae, Taeniidae, and Digenea. All these findings are new records for this sloth; also, two of them, Calodium sp. and Anoplocephalidae, have represented a risk for the health of ancient humans. Eggs of Calodium were similar to those previously isolated from ancient humans in Patagonia. Thus, Darwin’s ground sloth has represented a potential reservoir of zoonotic helminths, which is interesting considering this species was in close contact with humans in ancient Patagonia. Thus, additional collaboration with paleontologists is highlighted considering the incipient development of paleoparasitology in Chile, which could elucidate the presence of important pathogens, contributing to a better understanding of the evolution and changes in the distribution and virulence of certain parasites through time.

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.

A new species of strongyloid nematode from the genus Cloacina (Chabertiidae: Cloacininae) is described from the stomach of the hill kangaroo or euro (Macropus robustus) (Marsupialia: Macropodidae) from Western Australia. Cloacina atthis sp. nov. was found only in euros from the Pilbara region in the northwest of Western Australia, in spite of extensive collecting of the same host species from around the Australian continent. C. atthis is most closely related to Cloacina clymene, a species found in the same host species but only in the eastern half of the continent; the two species differ in minor morphological features (the shape of the wall of the buccal capsule, spicule lengths, the degree of sclerotisation of the gubernaculum and the shape of the vagina) as well as in differences in the internal transcribed spacers of ribosomal DNA. This study highlights the importance of using molecular methods when investigating the apparently disjunct distributions of strongyloid nematodes.

Specimens of Bertiella studeri (Cyclophyllidea, Anoplocephalidae) that have been preserved in ethanol or fixed permanently in formalin for >2 years were used for DNA extraction and molecular characterization. DNA was amplified via PCR from samples collected from different monkey and human hosts using eucestoda-specific primers. Phylogenetic trees were inferred from two sets of sequence data corresponding to the first and second halves of the 18S rDNA gene using two methods (distance-based NJ and maximum parsimony). We found that the second dataset was more suited for inferring phylogeny within the Cyclophyllidea. Both trees show that taxa belonging to the Anoplocephalidae, Hymenolepididae, Davaineidae, and Mesocestoididae are clearly monophyletic within their families and demonstrate sister-group relationships between the Anoplocephalidae and Mesocestoididae, contradicting previous reports of a basal placement of the Mesocestoididae within the Cyclophyllidea. The distance-based phylogeny support a taxonomical classification that groups members of the Bertiella genus, as well as other members of the Anoplocephalidae family, as being most closely related to the Hymenolepididae family and can be used to substantiate the use of uterine morphology as a valid homologous trait for taxonomical and phylogenetic classifications. On the other hand, the parsimony-based phylogeny places the Hymenolepididae closer to the outgroup and shows a closer relationship between the Mesocestoididae and the Taeniidae. This underlies the caution with which gene trees should be interpreted for inferring phylogeny and underlies the need to integrate both morphological and molecular data to represent the actual evolutionary pathway of the species involved.

The present study evaluates the phylogenetic position and systematic relationships of two species of Mosgovoyia Spasskii, 1951 and related genera (Cestoda: Anoplocephalidae) based on sequences of 28S ribosomal RNA and mitochondrial NADH dehydrogenase subunit 1 (Nad1) genes. Both molecular data-sets show that M. pectinata (Goeze, 1782) and Schizorchis caballeroi Rausch, 1960 are sister species and that they are phylogenetically independent from M. ctenoides (Railliet, 1890). This shows unambiguously that Mosgovoyia [sensu Beveridge (1978)] is a non-monophyletic assemblage, supporting the validity of Neoctenotaenia Tenora, 1976, erected for M. ctenoides. The results also show that the morphologically related Ctenotaenia marmotae (Fröhlich, 1802) is the sister species of Andrya rhopalocephala (Riehm, 1881) and therefore represents a more derived lineage. Modified diagnoses are provided for Mosgovoyia and Neoctenotaenia.

The tapeworm Moniezia expansa and naturally infected sheep were investigated with respect to their lead accumulation. Lead-Pb(CH(3)COO)(2) was added to the distilled water and administered orally to the sheep every day for a period of 1 week. After the exposure period the sheep were killed and the metal levels were determined in the muscle, liver, kidney and blood of the sheep as well as in the cestode parasites (Moniezia expansa). The impact of an infection with the cestode Moniezia expansa and a simultaneous Pb exposure, on the concentrations of heavy metals in the host kidney, liver, muscle, blood and cestodes was studied. The concentration of lead in the cestodes was on average 458, 5 and 4-fold higher in the cestodes than in the muscle, liver and kidney of the host, respectively. Parasitised sheep accumulated significantly less lead in their tissues than their uninfected conspecifics (ANOVA test, Por = 0.05). Also the differences between host's tissues and tapeworms were found to be significant (ANOVA test, Por = 0.05). Thus, this study reveals that lead accumulation also occurs in cestodes parasitizing mammals. The host-parasite-system sheep-Moniezia expansa appears to be a useful and promising bioindication system especially in farming (rural, agricultural) and the natural ecosystem.

Phylograms based on mitochondrial cytochrome oxidase I gene sequences show that the Anoplocephaloides variabilis (Douthitt, 1915)-like cestodes (Cestoda: Anoplocephalidae) from voles (Microtus spp.) and Paranoplocephala krebsi Haukisalmi, Wickstrom, Hantula & Henttonen, 2001 from collared lemmings (Dicrostonyx spp.) comprise a monophyletic group within the anoplocephaline cestodes. The patterns of phylogenetic, biological and/or biogeographical distinction suggest six or seven species of A. variabilis-like cestodes, including P. krebsi. However, at this time we decline to describe them as a series of new species as no straightforward morphological differences were found between the A. variabilis-like cestodes. A new genus, Microcephaloides n. g., is proposed for the cestodes earlier assigned to A. variabilis, A. cf. variabilis, A. tenoramuraiae Genov & Georgiev, 1988 and P. krebsi. A redescription is provided for the type-species, M. variabilis n. comb., from pocket gophers (Geomys spp. and Thomomys spp.). In addition to Anoplocephaloides Baer, 1927 (sensu stricto) and Microcephaloides, Paranoplocephaloides Gulyaev, 1996, Flabelloskrjabinia Spasskii, 1951 and Leporidotaenia Genov, Murai, Georgiev & Harris, 1990 are considered valid genera among cestodes previously assigned to Anoplocephaloides (sensu Rausch, 1976). The host spectrum and present phylogenetic data suggest that Microcephaloides has been primarily associated with voles (Microtus spp.) and its basal lineage now occurs in M. guentheri (Danford & Alston) in Turkey. Although the distribution and current host of the basal lineage suggest a western Palaearctic origin, subsequent diversification has probably occurred in eastern Beringia, because most of the more derived lineages occur partly or exclusively in Alaska.

A review of cestodes currently attributed to Progamotaenia zschokkei (Janicki, 1905) (Cestoda: Anoplocephalidae) suggests that six additional species are present: Pr. tenuis n. sp. found in Thylogale stigmatica (Gould) and T. thetis (Lesson), Pr. lomatosoma n. sp.from Macropus agilis (Gould), Pr. petrogale n. sp. from Petrogale spp. and Macropus dorsalis(Grey), Pr. fimbriata n.s p. from Lagorchestes conspicillatus Gould and L. hirsutus Gould, Pr. obesa n. sp. from Onychogalea fraenata (Gould) and O. unguifera (Gould) in north-eastern Australia and Pr. kellerae n. sp. from O. unguifera in north-western Australia. The new species are differentiated by a combination of characters: prominence of scolex lobes, number of lobes in the fimbriated velum, testis number and distribution, size of the cirrus-sac, morphology of the uterus and presence or absence of a pyriform apparatus in eggs from terminal segments. The morphological differences found support earlier molecular studies, in that cestodes within each host genus are distinct, with the exception that considerable morphological variation exists within Pr. petrogale. Principal components analysis suggested that most of the cestodes from Petrogale spp. belonged to Pr. petrogale. The status of specimens from Pe. lateralis is unclear. More detailed molecular studies are required to determine the significance of the morphological variation within this taxon. A key is provided to species within the complex and the related species Pr. villosa (Lewis, 1914).

A new species, Paranoplocephala buryatiensis n. sp. (Cestoda:Anoplocephalidae), is described from the grey-sided vole Clethrionomys rufocanus (Sundevall) in the Republic of Buryatia (Russian Federation) and compared with P. longivaginata Chechulin & Gulyaev, 1998, a parasite of the red vole C. rutilus (Pallas) in the same region. P. buryatiensis n. sp. and P. longivaginata both have an exceptionally long vagina and cirrus, unique features among known species of Paranoplocephala Luhe, 1910. The new species differs from P. longivaginata primarily by its wider and more robust body, lower length/width ratio of mature proglottides, tendency of testes to occur in two separate groups, seminal receptacle of a different shape and the position of the cirrus-sac with respect to the ventral longitudinal osmoregulatory canal. The cytochrome oxidase subunit I (COI) sequence data support the independent status of these species, and show that they form a monophyletic assemblage within Paranoplocephala (sensu lato). Assuming cospeciation, an indirect calibration using host speciation dates estimated a rate of mtDNA substitution of 1.0–1.7% pairwise (0.5–0.85% per lineage) sequence divergence per million years. A faunistic review of Paranoplocephala species in C. rufocanus and C. rutilus in the Holarctic region is presented.

A new genus, Viscachataenia, is erected to accommodate the anoplocephalid cestode Cittotaenia quadrata von Linstow, 1904, based on a redescription of the species from material collected from the chinchillid rodent Lagidium viscacia in Argentina. The new genus is characterised by paired genitalia, a reticulate uterus and the vagina entering the genital atrium anterior to the cirrus-sac. Viscachataenia therefore has similarities with Monoecocestus Beddard, 1914, a genus which is common in South American rodents but which has a single set of genitalia in each segment. Cittotaenia viscaciae (Spasskii, 1951) and Bertiella findlayi Mazza, Parodi & Fiora, 1932, also from viscachas, are considered synonyms of V. quadrata.

We present a redescription for Paranoplocephala macrocephala (Douthitt, 1915) in the type host, Geomys bursarius (Shaw) (hereafter PMG), and compare it with a P. macrocephala-like taxon in Microtus pennsylvanicus (Ord) (hereafter PMM) and P. kalelai (Tenora, Haukisalmi & Henttonen, 1985) in Clethrionomys rufocanus (Sundevall) using uni- and multivariate (discriminant analysis) morphometric methods. P. kalelai was found to be most divergent among these three taxa using both uni- and multivariate analyses, supporting its status as an independent species. Most of the observed metrical differences between PMG and PMM were found to reflect the larger body size of PMM; the relative size of organs (ratios) did not usually differ significantly between these taxa. The length/width ratio of mature segments was found to be the only size-independent feature that reliably separates PMG and PMM. Since PMM and PMG are also qualitatively very similar, e.g. with respect to the distribution of testes and morphology of the terminal genital ducts, the present analysis could not provide conclusive evidence against their conspecificity. However, the morphological variability and wide host and geographical distribution of P. macrocephala-like cestodes in North American voles of the genus Microtus, and the patterns of host-specificity within Paranoplocephala, suggest that this complex probably includes several species.

We describe the gastrointestinal helminth fauna of true lemmings (Lemmus spp., Arvicolinae) based on published and original material throughout the Holarctic range of these hosts. According to the existing data, the helminth fauna of true lemmings consists of three widespread and/or locally common taxa: Hymenolepis horrida (sensu lato) (Hymenolepididae), Anoplocephaloides lemmi (Anoplocephalidae) and Heligmosomoides spp. (Heligmosomidae). Despite the taxonomic boundaries and ancient phylogenetic splits in the hosts, there are no major faunistic differences for parasites within western (Siberian) L. sibiricus and L. bungei, and eastern (North American) L. trimucronatus throughout their distribution range. In contrast, the Norwegian lemming L. lemmus, which is a Fennoscandian endemic and closely related to the western populations of L. sibiricus, has only a single host-specific helminth, the cestode Paranoplocephala fellmani n. sp. (Anoplocephalidae). We describe the new species and show that it differs consistently from related species by its long and slender cirrus-sac. However, there are also a number of other significant differences, e.g., P. fellmani n. sp. and Andrya primordialis in Tamiasciurus hudsonicus (Sciuridae) evidently have a unique (sub)type of uterine development among Andrya/Paranoplocephala spp. Because P. fellmani n. sp. was also found to occur in Alaska (host L. trimucronatus), this species seems to follow the same biogeographical pattern as the other specialist helminths of Lemmus. We suggest alternative explanations for the absence of three major helminth taxa in the Norwegian lemming in Fennoscandia.

We describe Paranoplocephala serrata n. sp. (Cestoda, Anoplocephalidae) from collared lemmings Dicrostonyx torquatus and D. groenlandicus (Arvicolinae, Rodentia) in Arctic Siberia and North America. The new species was recorded from the Yamal Peninsula (type-locality), Yana Delta, Kolyma Delta, Wrangel Island, Alaska and Victoria Island/Kent Peninsula (Northwest Territories). P. serrata n. sp. is characterised by a long, ribbon-like strobila, distinctly serrated segments, a small scolex, unilateral or infrequently alternating genital pores and testes confined to the antiporal part of the segment. It differs from the related species (Andrya bairdi, Parandrya feodorovi and Paranoplocephala maseri) by several morphological features, including the distribution of testes (several testes antiporal to ventral longitudinal osmoregulatory canal), structure of the cirrus-sac and vagina, and large eggs (0.053–0.068 mm in the type-material). The material of P. serrata n. sp. from North America differs from the Siberian material by the shorter cirrus-sac, smaller dimensions of the female reproductive organs, larger seminal receptacle and larger eggs. However, the statistical differences in the dimensions of reproductive organs mainly reflect the larger size of mature segments in Siberian specimens compared with North American specimens. The main diagnostic features, i.e. the size and form of scolex and suckers, number and distribution of testes, position of female glands, vagina/cirrus-sac ratio and morphology of reproductive organs, do not differ markedly between the Palaearctic and Nearctic specimens. According to the structure of the early-stage uterus, A. bairdi Schad, 1954 belongs to the genus Paranoplocephala. Parandrya Gulyaev & Chechulin, 1996 is probably a synonym of Paranoplocephala. A redescription is provided for Paranoplocephala bairdi n. comb.

Paranoplocephala aquatica n. sp. is described from Arvicola terrestris and Ondatra zibethica (Rodentia, Cricetidae) in Bulgaria. The new species is characterised by a band-like strobila, a uterus forming a fine reticulate structure in the early stages of development, numerous testes (approximately 92) situated mainly aporally to the ovary in both the median and the aporal lateral fields, few testes positioned anterior to the ovary and genital ducts, the prominent asymmetrical situation of the female organs, the length of the vagina c. 0.65–0.68 of the length of the cirrus-sac, and the external seminal vesicle covered by a cellular sleeve. The new species is distinguished from P. ondatrae, P. macrocephala, P. dasymidis and P. sciuri. The specimens from O. zibethica reported as P. ondatrae by Tenora & Murai (1980) and as Aprostatandrya macrocephala by Spasskii et al. (1951) are believed to belong to P. aquatica. The type-series of P. ondatrae and P. macrocephala are redescribed and figured; metric data and an illustration of the holotype of P. sciuri are presented. The genus Paranoplocephala sensu Tenora et al. (1986) is regarded as a heterogeneous group because of the two patterns of uterine development in the species studied. Taxonomic criteria used for distinguishing the genera Andrya and Paranoplocephala, and some criteria applicable at the species level, are discussed.

A list of oribatid mites acting as intermediate hosts of tapeworms of the Anoplocephaldae is provided. to date, 127 species of oribatids included in 27 families, are implicated as intermediate hosts of the 14 genera and 27 species of anoplocephalid tapeworms. The most cited mites families are Oribatulidae with 35 species, Galumnidae with 22 species and Ceratozetidae with 15 species. Scheloribates laevigatus (Oribatulidae) is the species that demonstrated most susceptibility, both natural and experimental, to develop larval forms of anoplocephalid tapeworms. A theoretical-methodological model for parasitology based on the trophic characteristics of the intermediate and definitive mammalian hosts is reviewed.

Leporidotaenia n. g. is proposed for four cestode species parasitising Leporidae (Lagomorpha) which were previously considered as members of the genus Anoplocephaloides. The new genus is differentiated from Anoplocephaloides by the presence of a spinose covering on the tegument, the protrusible genital atrium, the massive cirrus-sac with highly developed musculature, the presence of a retractor muscle associated with the cirrus-sac, the posterior position of vaginal pore relative to the male orifice, the cirrus armed with long spines and its occurrence only in hosts of the family Leporidae (Lagomorpha). The genus includes: L. romerolagi (type-species), L. floresbarroetae, L. pseudowimerosa and L. wimerosa. the species (excluding L. floresbarroetae) are redescribed and figured and a differential key is presented. An attempt is made to explain the range of Leporidotaenia spp. in Central America and the western Palaearctic on the basis of the palaeozoogeography of rabbits and hares.

The following new species of Bertiella are described: B. affinis n. sp. from Pseudocheirus peregrinus (Australia); B. arnhemensis n. sp. from P. dahli (Australia); B. baylisi n. sp. from Uromys caudimaculatus (Australia); B. belidicola n. sp. from P. lemuroides (Australia); B. esculenta n. sp. from P. cupreus (Papua-New Guinea); B. flanneryi n. sp. from P. cupreus (Papua-New Guinea); B. imperfecta n. sp. from Phalanger carmelitae (Papua-New Guinea); B. paraberrata n. sp. from Pseudocheirus peregrinus (Australia); B. phalangeris n. sp. from Phalanger carmelitae (Papua-New Guinea); B. redmondi n. sp. from Pseudocheirus corinnae (Papua-New Guinea); B. vesicularis n. sp. from P. lemuroides (Australia); B. paucitesticulata n. sp. from P. corinnae (Papua-New Guinea). Species redescribed are: B. aberrata Nybelin, 1917 from P. herbertensis (Australia); B. anapolytica Baylis, 1934 from Rattus fuscipes, R. lutreolus (Australia); B. kapul Baylis, 1934 from Phalanger maculatus (Papua-New Guinea). B. pellucida Nybelin, 1917, B. pseudochiri Nybelin, 1917, B. undulata Nybelin, 1917 and B. campanulata (Nybelin, 1917) n. comb., are recorded for the first time from Pseudocheirus archeri and doubt is cast on their original records from P. lemuroides and P. herbertensis. Parabertiella Nybelin, 1917 is suppressed as a synonym of Bertiella. B. trichosuri Khalil, 1970 is reported from a new host, Wyulda squamicaudata. Additional geographical records are given for B. foederata Beveridge, 1976. B. rigida Janicki, 1906 is considered to be a species inquirenda. ac]19840501

Bertiella elongata (Bourquin, 1905) andB. plastica (Sluiter, 1896) both fromCynocephalus volans (Linnaeus, 1758) andC. variegatus (Audebert, 1799) are redescribed and illustrated. A neotype forB. plastica is designated.B. boholensis Spasskii, 1951 is reduced to synonymy withB. elongata andB. cynocephali Spasskii, 1951 is synonymised withB. plastica. A new species,B. rauschi, is described fromC. volans in the Philippines. It differs from its congeners in having an accessory seminal receptacle and testes which do not extend to the aporal extremity of the medulla.Bertiella musasabi Yamaguti, 1942 is redescribed from a specimen fromPetaurista petaurista (Pallas, 1766) from Taiwan.Indotaenia indica Singh, 1962 andAprostatandrya petauristae Sawada & Kugi, 1979 become synonyms ofB. musasabi. The biogeography of the genus is briefly discussed.

Three new species of Progamotaenia (Cestoda: Anoplocephalidae) are described from macropodid marsupials in Australasia. P. wallabiae n. sp. from Dorcopsis veterum in New Guinea is most similar to P. bancrofti (Johnston, 1912), P. johnsoni Beveridge, 1980, and P. aepyprymni Beveridge, 1976. It differs from P. aepyprymni in the occurrence of the testes in two lateral groups and the lateral position of the female genitalia, and differs from all three species in the number of testes and the lack of a pyriform apparatus. P. dorcopsis n. sp. also from D. veterum in New Guinea and P. queenslandensis n. sp. from Thylogale stigmatica in north-eastern Queensland are most closely related to P. lagorchestis (Lewis, 1914) and P. thylogale Beveridge & Thompson, 1979, differing in the number and distribution of the testes, the absence of proterogyny, the proglottis velum and pyriform apparatus. The number and distribution of testes are the main features distinguishing P. dorcopsis from P. queenslandensis. ac]19840112

Australian species of the genus Linstowia are redescribed, and one new species, L. macrouri is added. The new species differs from L. echidnae in the size of the cirrus sac and the distribution of the testes. L. tasmanica Spasskii, 1951 is regarded as a synonym of L. echidnae. L. echidnae and L. macrouri are placed in the nominal subgenus Linstowia; L. semoni and L. jheringi are placed in the subgenus Paralinstowia. ac]19821215