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Jean-lou Justine - One of the best experts on this subject based on the ideXlab platform.

Ian Beveridge - One of the best experts on this subject based on the ideXlab platform.

Voitto Haukisalmi - One of the best experts on this subject based on the ideXlab platform.

  • taxonomy and diversity of paranoplocephala spp Cestoda anoplocephalidae in voles and lemmings of beringia with a description of three new species
    Biological Journal of The Linnean Society, 2006
    Co-Authors: Voitto Haukisalmi, Heikki Henttonen, Lotta M Hardman
    Abstract:

    The present study reviews the taxonomy, diversity, and zoogeography of Paranoplocephala spp. (Cestoda: Anoplocephalidae) in arvicoline rodents (voles and lemmings) in Beringia (north-east Siberia and Alaska) based on combined morphological and molecular evidence, and compares the Beringian fauna with the corresponding European fauna. The overall species diversity was marginally higher in Beringia (13 spp.) than in Europe (11 spp.). The Beringian cestode fauna was found to be a mixture of Nearctic and Holarctic species, whereas the European fauna had a high proportion of ‘endemic’ (western Eurasian or European) species. In addition, there was a pronounced difference in species diversity within Beringia, with four to six species in north-east Siberia vs. 12 species in Alaska, reflecting the fact that two faunal elements of hosts and parasites (Nearctic and Holarctic) meet in the latter region. The Paranoplocephala spp. of arvicoline rodents in Beringia represent multiple faunistical and zoogeographical elements, possibly indicating different responses to vicariant situations due to the glacial or interglacial periods. The study includes a description of three new Paranoplocephala species (Paranoplocephala batzlii sp. nov., Paranoplocephala freemani sp. nov., Paranoplocephala jarrelli sp. nov.) in Microtus voles. © 2006 The Linnean Society of London, Biological Journal of the Linnean Society, 2006, 89, 277–299.

  • molecular and morphological evidence for multiple species within paranoplocephala omphalodes Cestoda anoplocephalidae in microtus voles arvicolinae
    Zoologica Scripta, 2004
    Co-Authors: Voitto Haukisalmi, Heikki Henttonen, Lotta M. Wickström, Jarkko Hantula, András Gubányi
    Abstract:

    Haukisalmi, V., Wickstrom, L. M., Henttonen, H., Hantula, J. & Gubanyi, A. (2004). Molecular and morphological evidence for multiple species within Paranoplocephala omphalodes (Cestoda, Anoplocephalidae) in Microtus voles (Arvicolinae). —Zoologica Scripta, 33, 277–290. The present study was designed to test the hypothesis that the anoplocephalid cestode Paranoplocephala omphalodes (Hermann, 1783), a Holarctic parasite of Microtus voles, is a complex of host-specific species, rather than a single host-generalist species, using uni- and multivariate morphometrics and DNA sequence data from the mitochondrial cytochrome oxidase I gene. The phylogenetic methods applied to the mtDNA sequence data showed consistently that the cestodes morphologically recognizable as P. omphalodes include four well-supported monophyletic groups, representing at least three distinct, largely host-specific species. Multivariate morphometrics (discriminant analysis) successfully distinguished the four main mtDNA clades of P. omphalodes-like cestodes. The true P. omphalodes is shown to be a parasite of Microtus arvalis, M. agrestis and Clethrionomys glareolus in Europe. Microtus oeconomus harbours two host-specific, allopatric and possibly conspecific clades, one with a Holarctic and another with an (eastern) Beringian (Alaskan) distribution. The eastern Beringian endemic M. miurus is also parasitized with a host-specific, morphologically divergent species of Paranoplocephala. The cestode clades recognized in M. oeconomus and M. miurus represent 2–3 undescribed species. Molecular phylogenetic analyses supported the monophyly of the ‘northern clade’ of Paranoplocephala spp., an assemblage including P. kalelai from Clethrionomys spp., P. macrocephala from Microtus spp. and all clades of P. omphalodes-like cestodes except those representing the true P. omphalodes from Europe. The intra- and interspecific phylogeny within the northern clade is compared tentatively with the known evolutionary history of the hosts.

Larisa G. Poddubnaya - One of the best experts on this subject based on the ideXlab platform.

  • heteromorphism of sperm axonemes in a parasitic flatworm progenetic diplocotyle olrikii krabbe 1874 Cestoda spathebothriidea
    Parasitology Research, 2020
    Co-Authors: Magdalena Bruňanska, Martina Matouskova, Renata Jasinska, Jana Nebesařova, Larisa G. Poddubnaya
    Abstract:

    The spermatozoon ultrastructure of the progenetic cestode Diplocotyle olrikii (Spathebothriidea) has been examined using transmission electron microscopy and cytochemical staining with periodic acid-thiosemicarbazide-silver proteinate (PA-TSC-SP) for glycogen. The spermatozoon is a filiform cell, tapered at both extremities. Its moderately electron-dense cytoplasm possesses two parallel axonemes of unequal lengths. New for the Cestoda is a finding of three types of the mature spermatozoa with respect to different axonemal structure. The first type has both axonemes with standard 9 + '1' trepaxonematan pattern. The second type is represented by a spermatozoon having one axoneme with 9 + '1' structure and the second one with 9 + 0 pattern. The third type includes the two axonemes with 9 + 0 pattern. Microtubule doublets of the 9 + 0 axonemes contain either inner dynein arms or no dynein arms. In addition to the two axonemes, all three types of the mature sperm cells contain parallel nucleus, parallel cortical microtubules, four electron-dense plaques/attachment zones, and glycogen. The anterior extremity of the gamete exhibits a centriole surrounded by a semiarc of up to five electron-dense tubular structures. The distal end of the first type spermatozoa exhibits two morphological variants, represented either by (i) nucleus or (ii) remnants of the disorganized axoneme. Distal extremity of the spermatozoa of the second and third types contains doublets and singlets of disorganized axoneme. The ultrastructural characters of the spermatozoon of progenetic D. olrikii support the basal position of the Spathebothriidea within the EuCestoda.

  • Ultrastructure of the ovary of Amphilina japonica Goto & Ishii, 1936 (Cestoda) and its implications for phylogenetic studies
    Systematic Parasitology, 2010
    Co-Authors: Larisa G. Poddubnaya, Willi E R Xylander
    Abstract:

    The ultrastructure of the ovary of the amphilinidean cestode Amphilina japonica Goto & Ishii, 1936 from the body-cavity of the American sturgeon Acipenser transmontanus Richardson is described using transmission electron microscopy. The characters of the ovary of Amphilina japonica are different from those of all other cestodes. The most important difference is in the nature of the relationship between the germ and accessory cells within the ovary. In A. japonica the oocytes and accessory cells form numerous different intercellular contacts (desmosome-like junctions and zonulae adherentes). Gap junctions are present between the narrow cytoplasmic processes of the accessory cells. Numerous micropinocytotic vesicles and vacuoles from the accessory cells discharge their content into spaces between the oocytes and the accessory cells. The accessory cells are closely associated with the oocytes during the early and middle stages of oogenesis. As the volume of oocytes increases, the accessory cells gradually lose their association with the oocyte surfaces. Peripherally located individual accessory cells of A. japonica give rise to a cellular epithelial layer of irregular shape and thickness which breaks down via numerous invaginations of the basal membrane and underlying basal matrix. The different arrangements of the interconnection of cell components in the Amphilinidea compared with the Gyrocotylidea and EuCestoda (the absence of specialised cell contacts and the syncytial nature of the accessory ‘interstitial’ cells) are evidence suggesting the presence of unrelated groups within the Cestoda. The nature of the association of the accessory and germ cells in ovary of A. japonica more closely resembles the ovary of non-platyhelminth invertebrates rather than that of other neodermatans.

Tomáš Scholz - One of the best experts on this subject based on the ideXlab platform.

  • tapeworms Cestoda proteocephalidea of teleost fi shes from the amazon river in peru additional records as an evidence of unexplored species diversity
    Revue Suisse De Zoologie, 2015
    Co-Authors: Alaiin De Chambrier, Tomáš Scholz, Roman Kuchta
    Abstract:

    This paper represents an update of the previous list of adult proteocephalidean tapeworms (Cestoda) parasitizing freshwater teleosts from the Peruvian Amazon, which was presented by de Chambrier et al. (2006a). Four new samplings made it possible to almost double the number of species found, all of them representing new geographical records from Peru. With 34 newly added species, a total of 63 proteocephalidean cestodes (46 named species of 27 genera) are now reported from Amazonia in Peru (compared to 54 named species of 28 genera from its Brazilian part). The genera previously unreported by de Chambrier et al. (2006a) are Ageneiella, Brayela, Endorchis, Ephedrocephalus, Gibsoniela, Harriscolex, Jauella, Lenhataenia, Manaosia, and Megathylacus. Four species, namely Jauella glandicephalus, Monticellia belavistensis, M. santafesina, and Proteocephalus hobergi, are reported from the Amazon River basin for the fi rst time. Harriscolex piramutab (Woodland, 1934) n. comb. is proposed for specimens previously identifi ed as Proteocephalus piramutab Woodland, 1934 from Brachyplatystoma vaillantii. The highest number of proteocephalidean cestodes is reported from Pseudoplatystoma fasciatum (a total of 10 cestode species), Zungaro zungaro (previously named Paulicea luetkeni; 9 species) and Phractocephalus hemioliopterus (6 species). A high number of unnamed species found in Peru (17), which most probably represent taxa new to science including at least two new genera, demonstrates that the species richness of proteocephalidean cestodes in Amazonia is still poorly known.

  • conflict between morphology and molecular data a case of the genus caryophyllaeus Cestoda caryophyllidea monozoic tapeworms of cyprinid fishes
    Folia Parasitologica, 2014
    Co-Authors: Eva Bazsalovicsova, Ivica Kralovahromadova, Jan Brabec, Vladimira Hanzelova, Mikulas Oros, Tomáš Scholz
    Abstract:

    Molecular analysis of an extensive specimen collection of morphologically distinct tapeworms of the genus Caryophyllaeus Gmelin, 1790 (Cestoda: Caryophyllidea), parasites of cyprinid fishes in the Palaearctic Region, brought evidence of host-related plasticity in critical morphological characters widely used for species circumscription and classification of these tapeworms. The results obtained here do not support the traditionally used morphological concept of species-defining characters of the order Caryophyllidea Carus, 1863, especially due to high morphological plasticity of the scolex and the anterior end of the body. Several morphotypes within both Caryophyllaeus laticeps (Pallas, 1781) and Caryophyllaeus brachycollis Janiszewska, 1953 generally corresponding to different hosts and geographical regions, were recognised likely suggesting host- and geography-related intraspecific morphological variability. Genetic data confirmed euryxenous host specificity of both species, most profoundly C. laticeps, but did not support the existence of cryptic species. In fact, some of the fish hosts may harbour both of the congeneric species including several of their respective morphotypes. The pattern of morphological and genetic divergence observed in both cestode species studied indicates a scenario of possible host range extensions and subsequent parasite diversification. If molecular sequence variability and host-related morphological polymorphism are confirmed in other groups of monozoic cestodes, it may complicate species identification and straightforward classification of these parasites.

  • Ultrastructure of microtriches on the scolex of Cyathocephalus truncatus (Cestoda: Spathebothriidea).
    Folia Parasitologica, 2008
    Co-Authors: Céline Levron, Tomáš Scholz, Bahram S. Dezfuli
    Abstract:

    The scolex surface of the mature spathebothriidean Cyathocephalus truncatus (Pallas, 1781), a parasite of the brown trout Salmo trutta fario L., was studied using scanning and transmission electron microscopy. A particular attention was paid to microtriches, unique structure on the surface of the Cestoda. The scolex of C. truncatus is covered with two types of filiform microtriches (filitriches): aciculate (≈ 3 µm long) and capillate (≈ 10 µm long). Capillate microtriches, which have never been reported in any other spathebothriideans, are described for the first time using transmission electron microscopy. The tegument covered with filiform microtriches only (no spiniform microtriches are present) is typical of cestode groups supposed to be the most basal, e.g., Gyrocotylidea, Spathebothriidea, and Caryophyllidea.

  • on the position of archigetes and its bearing on the early evolution of the tapeworms
    Journal of Parasitology, 2008
    Co-Authors: Peter D Olson, D T J Littlewood, L G Poddubnaya, Tomáš Scholz
    Abstract:

    The tapeworm Archigetes sieboldi Leuckart, 1878 (Platyhelminthes: Cestoda: Caryophyllidea) has been cited as a likely representative of the “protocestode” condition, owing to its lack of segmentation and ability to attain sexual maturity in the invertebrate host (aquatic oligochaetes). The idea has been variously amplified or rejected in the literature, although the actual phylogenetic position of the species has not been investigated until now. New collections of Archigetes sp. from both its vertebrate and invertebrate hosts provided the opportunity to estimate its phylogenetic position with the use of molecular systematics, while prompting new analyses aimed at assessing the early diversification of the Cestoda. Additional collections representing the Amphilinidea, Caryophyllidea, and Gyrocotylidea were combined with published gene sequences to construct data sets of complete 18S (110 taxa) and partial (D1-D3) 28S (107 taxa) rDNA sequences, including 8 neodermatan outgroup taxa. Estimates resulting from...

  • Ultrastructural characters of the spermatozoon of the cestode Corallobothrium solidum Fritsch, 1886 (Cestoda: Proteocephalidea), a parasite of the electric catfish Malapterurus electricus
    Parasitology Research, 2004
    Co-Authors: Magdaléna Bruňanská, Tomáš Scholz, Mohammed Hassan Ibraheem
    Abstract:

    The fine structure of the mature spermatozoon of the corallobothriine tapeworm Corallobothrium solidum Fritsch, 1886 (Cestoda: Proteocephalidea) from the electric catfish Malapterurus electricus from the Nile River in Egypt was studied by transmission electron microscopy for the first time. The filiform spermatozoon of C . solidum contains two axonemes of unequal length and a typical 9+”1” trepaxonematan pattern. A single helicoidal crested body (30–200 nm thick) is localized at the anterior extremity of the gamete. The cortical microtubules line the periphery of the cell, largely parallel to the long axis of the spermatozoon and exhibiting signs of twisting at the beginning of region II. The nucleus, in the form of an electron-dense (largely in gametes of testes) and/or fibrous cord (largely in gametes from male reproductive ducts and seminal vesicle), coils in a spiral through the middle part (region III) of the spermatozoon. The cytoplasm contains electron-dense granules in regions II, III and partly in region IV. The cytoplasm of some spermatozoa exhibits an apparently higher electron-density at the end of the nucleated region (III), and continuously toward the middle part of region IV. The anterior and posterior extremities of the spermatozoa have a single axoneme. The ultrastructural features of the mature spermatozoon of C. solidum mostly coincide with those of the spermatozoon of other proteocephalideans, especially the gangesiine Electrotaenia malopteruri parasitizing the same host.