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  • Scolex morphology of monozoic tapeworms caryophyllidea from the nearctic region taxonomic and evolutionary implications
    Folia Parasitologica, 2020
    Co-Authors: Mikulas Oros, Anindo Choudhury, Dalibor Uhrovic, John S Mackiewicz, Tomas Scholz
    Abstract:

    A comparative study of the scoleces of monozoic tapeworms (Cestoda: Caryophyllidea), parasites of catostomid and cyprinid fishes (Teleostei: Cypriniformes) in the Nearctic Region, was carried out using light and scanning electron microscopy. Scoleces of 22 genera of North American caryophyllideans were characterised and their importance for taxonomy, classification and phylogenetic studies was critically reviewed. Nearctic genera exhibit a much higher variation in the shape and form of scoleces compared with taxa in other biogeographical regions. The following basic Scolex types can be recognised in Nearctic caryophyllideans: monobothriate (Promonobothrium Mackiewicz, 1968), loculotruncate (Promonobothrium, Dieffluvium Williams, 1978), bothrioloculodiscate (Archigetes Leuckart, 1878, Janiszewskella Mackiewicz et Deutsch, 1976, Penarchigetes Mackiewicz, 1969, Pseudoglaridacris Oros, Uhrovic et Scholz, 2018), fixomegabothriate (Capingens Hunter, 1927), bulbate and bulboacuminate (Atractolytocestus Anthony, 1958), cuneiloculate (Hypocaryophyllaeus Hunter, 1927, Rowardleus Mackiewicz et Deutsch, 1976, Spartoides Hunter, 1929), biacetabulate, bulboloculate, bothrioloculodiscate (Biacetabulum Hunter, 1927), tholate (Hunterella Mackiewicz et McCrae, 1962), cuneifimbriate (Khawia Hsu, 1935), cuneiform (Calentinella Mackiewicz, 1974, Caryophyllaeides Nybelin, 1922, Edlintonia Mackiewicz, 1970), hastate (Pseudolytocestus Hunter, 1929), loculotholate (Bialovarium Fischthal, 1953, Pliovitellaria Fischthal, 1951), and cuneiformoloculate (Glaridacris Cooper, 1920, Isoglaridacris Mackiewicz, 1965). The same type of Scolex may be shared by species of different genera or families and species of the same genus can have a Scolex of conspicuously different morphology, e.g. in Promonobothrium. Scolex morphology may be therefore of limited use in generic designation.

  • FIGURES 8–16. Cichlidocestus janikae n. g., n in A New Genus And Two New Species Of Proteocephalidean Tapeworms (Cestoda) From Cichlid Fish (Perciformes: Cichlidae) In The Neotropics
    2017
    Co-Authors: Alain Chambrier, Carlos Daniel Pinacho-pinacho, Jesus Servando Hernández-orts, Tomas Scholz
    Abstract:

    FIGURES 8–16. Cichlidocestus janikae n. g., n. sp. from Hypsophrys nicaraguensis, Costa Rica, line drawings. (8) Scolex, dorsal view (paratype 3 – CNHE No. 10044). (9) Frontal sections of Scolex, showing the anterior circular musculature of suckers (paratype 4 – MHNG-PLAT 94086). (10) Frontal sections of the Scolex, showing an apical sucker (paratype 4 – MHNG-PLAT 94086). (11, 12) Cross sections at level of the cirrus-sac and ovary, respectively (holotype – IPCAS C-734). (13) Pregravid proglottid, ventral (holotype – MHNG-PLAT 94085); the uterus is not drawn and the ventral osmoregulatory canals are not all figured. (14, 15) Eggs (paratype 4 – MHNG-PLAT 94086). (16) Terminal genitalia, ventral (holotype – MHNG-PLAT 94085). Abbreviations: as – apical sucker; cc – chromophilic cells lining uterine diverticula; ci – cirrus; cm – circular musculature; cs – cirrus-sac; du – diverticula of uterus; eh – embryonic hooks; em – bilayered embryophore; gc – gland cells; ilm – internal longitudinal musculature; isv – internal seminal vesicle; mg – Mehlis' gland; oe – outer envelope; on – oncosphere; ov – ovary; pc – prostatic cells; sc – subtegumental cells; sd – sperm duct; sr – seminal receptacle; st – subtegumental muscle fibers; su – sucker; te – testes; tg – tegument; ut – uterus; vc – vaginal canal; vd – vitelline duct; vf – vitelline follicles; voc – ventral osmoregulatory canal; vs – vaginal sphincter

  • Republic
    2016
    Co-Authors: Zdeňka Žďárská, Tomas Scholz, Jana Nebesářová
    Abstract:

    Abstract. In the apical glandular region of the adult Proteocephalus torulosus (Batsch, 1786), two types of eccrine gland cells are present. The first type of unicellular gland produces large electron-dense granules of various sizes. The second type contains small electron-dense granules. Most cells form glands with large granules; glands with small granules are infrequent. The secretion of both types of gland cells is concentrated in the apical parts of the cyton and in the ducts opening to the exterior. On the Scolex of P. torulosus, there are regional structural differences of the microthrix border. The apical glandular region bears filamentous microtriches only. On the remaining frontal part, surrounding the glandular region, there are blade-like and filamentous microtriches. The lateral parts of the Scolex and suckers bear blade-like microtriches. Possible functions of both types of gland cells and different parts of the Scolex microthrix border are discussed. The unique structure of the frontal part of the Scolex of P. torulosus and its differences from Proteocephalus macrocephalus, P. longicollis and P. percae correlate well with the putative basal phylogenetic position of P. torulosus among European species of Proteocephalus. The information about the ultrastructure of the tegu-ment, including gland cells, may be useful in the sys-tematics of proteocephalidean and other fish cestode

  • ULTRASTRUCTURE OF MICROTRICHES ON THE Scolex OF CYATHOCEPHALUS TRUNCATUS (CESTODA: SPATHEBOTHRIIDEA)
    2015
    Co-Authors: Céline Levron, Tomas Scholz, Bahram S. Dezfuli
    Abstract:

    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., Gyrocoty-lidea, Spathebothriidea, and Caryophyllidea. The tegument of tapeworms (Cestoda) is covered with

  • morphological polymorphism in tapeworms redescription of caryophyllaeus laticeps pallas 1781 cestoda caryophyllidea and characterisation of its morphotypes from different fish hosts
    Systematic Parasitology, 2015
    Co-Authors: V Hanzelová, Mikulas Oros, Daniel Barcak, Dana Miklisova, Diana Kirin, Tomas Scholz
    Abstract:

    Recent morphological and molecular data have shown that one of the most common parasites of freshwater fish in the Palaearctic Region, the cestode Caryophyllaeus laticeps (Pallas, 1781) (Eucestoda: Caryophyllidea), is highly polymorphic. Five distinct morphotypes of C. laticeps, largely corresponding to different fish hosts and representing separate, yet closely related genetic lineages, have been recognised and they are characterised in the present paper. Morphotype 1 from breams, Abramis brama (L.) (type-host) and Ballerus spp., corresponds to the original Taenia laticeps Pallas, 1781 and its neotype (paragenophore ex A. brama in Russia) is designated. This morphotype is characterised by a slender body and flabellate Scolex. Morphotype 2 was found in the Macedonian vimba Vimba melanops (Heckel) and the vimba bream V. vimba (L.); it is typified by a more robust body, with most anterior extent of the vitelline follicles near the Scolex and the cirrus-sac situated more anteriorly than in other morphotypes. Morphotype 3 is represented by worms from the common carp Cyprinus carpio L. that possess a cuneicrispitate Scolex (having the form of a wedge with shallow indentations on anterior margin). Morphotype 4 from the common nase Chondrostoma nasus (L.) has a large, robust body and a wide Scolex with numerous superficial grooves (wrinkles) in its anterior part. Morphotype 5 is represented by worms from the white-eye bream Ballerus sapa (Pallas); its typical characteristics are a festoon-like anterior margin of the Scolex, the absence of vitelline follicles posterior to the cirrus-sac and the absence of a well-developed internal seminal vesicle. Discriminant analysis of 15 morphometric variables readily separated Morphotypes 3, 4 and 5 and confirmed the key discriminating power of traits related to the reproductive system, especially the terminal reproductive organs. Morphological polymorphism and the genetic divergence of different morphotypes of C. laticeps correspond to its wide spectrum of fish definitive hosts and a large distribution area that includes Europe, most of Palaearctic Asia and northern Africa.

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