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1

Philotolepis raymondi [Gigon et Beuret, 1991] comb.n. [Cyclophyllidea, Dilepididae]: new geographical record and synonymy

100%

Georgiev B. B. , Genov T.

Acta Parasitologica

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1993

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tom 38

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nr 3

EN

Ptilotolepis raymondi (Gigon et Beuret, 1991) comb. n. (Syns. Unciunia raymondi Gigon et Beuret, 1991; Ptilotolepis philomelae Okulewicz, 1991, new synonymy) is recorded and redescribed from Turdus philomelos (Passeriformes, Muscicapidae, Turdinae) in Bulgaria. The same specimens were mentioned as Anomotaenia constricta by Paspalev and Paspaleva 1972 and as Ptilotolepis sp. by Georgiev 1990. P. raymondi is regarded as a species specific parasite of T. philomelos.

2

Ultrastructural studies on the oncospheral envelopes of six species of genus Diorchis [Cyclophyllidea, Hymenolepididae]

88%

Chomicz L.

Acta Parasitologica

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1993

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tom 38

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nr 4

EN

The aim of the present study was to describe ind compare the ultrastructure of oncospheral envelopes in closely related species within the same genus, Diorchis. The envelopes of the following species were examined: Diorchis brevis, D. ovofurcata, D. inflata and D. elisae (filiform, infective eggs), and D. parvogenitalis and D. stefanski (oval shaped eggs). Two categories of oncospheral envelopes are distinguished: the primary cytoplasmic and secondary non-cytoplasmic envelopes. All diorchids examined, in distinction to other hymenolepidids, show at the end of the oncospheral differentiation: (1) a much thicker, clearly striated oncospheral membrane; (2) a three-layered embryophore; (3) the presence of an additional zone of electron-dense aggregates resembling a honeycomb; and (4) an asynchronous differentiation of the derivatives of the inner envelopes. Some ultrastructural differences in oncospheral envelopes of diorchids with oval shaped and filiform oncospheres are described and their significance is discussed.

3

Fertilization in the cestode Echinococcus multilocularis (Cyclophyllidea, Taeniidae)

75%

Swiderski Z. , Miquel J. , Azzouz-Maache S. , Petavy A.-F.

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tom 61

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nr 1

4

Egg ultrastructure of the amabiliid cestode Tatria biremis Kowalewski, 1904 (Cyclophyllidea, Amabiliidae), with an emphasis on the oncospheral envelopes

75%

Tkach V. , Swiderski Z. , Mlocicki D.

Acta Parasitologica

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2013

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tom 58

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nr 3

EN

This is the first report on the ultrastructure of eggs in the cestode family Amabiliidae Braun, 1900. The gravid proglottides of Tatria biremis easily detach from the strobila. Their thick-walled saccate uterus contains numerous rounded or oval eggs measuring about 30-32 μm in diameter. In the early preoncospheral phase, three primary embryonic envelopes are formed around the developing and differentiating embryos, namely: (1) vitelline capsule originating from vitellocyte material; (2) outer envelope formed by two macromeres, and (3) inner envelope originating from a fusion of three mesomeres. Thus, both the outer and inner envelopes of T. biremis eggs are cellular in origin and syncytial in nature. During egg maturation, the three primary embryonic envelopes undergo differentiation into fully formed oncospheral or egg envelopes. Most significant changes were observed in the inner envelope which becomes progressively subdivided into 3 sub-layers: the extra-embryophoral sub-layer, the embryophore, and the intra-embryophoral sub-layer, containing mesomere nuclei. The mature hexacanth is covered by a thin layer of the oncospheral tegument. Within the infective hexacanth larva, five cell types were distinguished: (1) a binucleated subtegumental cell; (2) U-shaped penetration gland; (3) nerve cells; (4) somatic cells representing the myocytons of both somatic and hook musculature, and (5) large germinative cells. Ultrastructural characteristics of T. biremis eggs are compared with those described in representatives of other cestode taxa. Since the functional ultrastructure of cestode egg envelopes is defined by multiple factors such as the type of life cycles, habitats and behaviour of the intermediate hosts, mode of the intermediate host infection, etc., ultrastructural studies of the greater diversity of cestodes are needed to obtain comparative data for fruitful analysis of cyclophyllidean cestode adaptations to their diverse life cycles.

5

Vitellogenesis in Mosgovoyia ctenoides [Railliet, 1890] Beveridge, 1978 [Cyclophyllidea, Anoplocephalidae]

75%

Swiderski Z. , Mlocicki D. , Eira C. , Miquel J. , Grytner-Ziecina B. , Mackiewicz J. S.

Acta Parasitologica

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2005

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tom 50

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nr 4

EN

Vitellogenesis in Mosgovoyia ctenoides was examined by means of transmission electron microscopy. Mature vitelline follicles consist of cells in various stages of development, progressing from immature cells of gonial type near the periphery to mature vitellocytes towards the centre. Maturation is characterized by: (1) increase in cell volume; (2) extensive development of large parallel cisternae of granular endoplasmic reticulum (GER), the vitelline material producing units; (3) development of Golgi complexes engaged in vitelline material package; (4) continuous fusion of small vesicles into larger vitelline vesicles and fusion of these into a single very large vesicle, which is characteristic for mature vitellocytes of this tapeworm. Vitellogenesis in M ctenoides is compared with that in other cestodes. Some conclusions concerning the interrelationship between the vitellogenesis pattern and the type of embryogenesis are drawn and discussed.

6

Ultrastructure of oncospheral envelopes at the final stage of infective - egg formation in some species of Cyclophyllidea

75%

Chomicz L. , Walski M.

Wiadomości Parazytologiczne

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1998

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tom 44

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nr 3

7

Elektron microscope study on vitellogenesis in Catenotaenia pusilla [Goeze, 1782] [Cyclophyllidea, Catenotaeniidae]

75%

Swiderski Z. , Chomicz L. , Grytner-Ziecina B. , Tkach V. V.

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tom 45

|

nr 2

EN

The vitellogenesis in Catenotaenia pusilla was examined by means of electron microscopy. Mature vitelline follicles consist of cells in various stages of development, progressing from immature cells of gonial type near the periphery to mature vitellocytes towards the centre. Maturation is characterised by: (1) increase in cell volume; (2) extensive development of large parallel cisternae of GER, the vitelline material producing units; (3) development of Golgi complexes engaged in vitelline material package; (4) continuous fusion of small vesicles into larger vitelline vesicles and fusion of these into 3 very large vesicles, which are characteristic for mature vitellocytes of this tapeworm. Vitellogenesis in C. pusilla is compared with that in other cestodes. Some conclusions concerning the interrelationship between the vitellogenesis pattern and the type of embryogenesis are drawn and discussed.

8

Ultrastructure of spermatogenesis of Taenia taeniaeformis [Batsch, 1786] [Cestoda, Cyclophyllidea, Taeniidae] and comparison of spermatological characters in the family Taeniidae Ludwig, 1886

63%

Miquel J. , Swiderski Z. , Foronda P. , Torres J. , Feliu C.

Acta Parasitologica

|

2009

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tom 54

|

nr 3

230-243

EN

The ultrastructure of spermatogenesis of Taenia taeniaeformis is described for the first time by means of transmission electron microscopy (TEM). Mature testes contain all stages of spermatogenesis; primary spermatogonia are usually situated at the periphery and mature spermatozoa in the centre of testes. The general process is similar to that described in other cestodes. Six incomplete, synchronic cytokineses occur: four mitotic and two meiotic cell divisions. All these divisions occur simultaneously, resulting in a rosette cluster of four tertiary spermatogonia, then eight quaternary spermatogonia, and subsequently sixteen primary spermatocytes. All of these enter into a growth period and their enlarged nuclei move to the periphery of cells of the rosettes. The first meiotic division forms thirty-two secondary spermatocytes and after the second meiotic division, there are sixty-four spermatids. Spermiogenesis in T. taeniaeformis corresponds to the Ba and Marchand’s Type 3 and begins with the formation of a differentiation zone in the form of a conical projection of cytoplasm delimited by a ring of arching membranes and surrounded by submembranous cortical microtubules. Within this area, there are two centrioles, orthogonally disposed, and vestigial striated rootlets. Only one of the centrioles develops a flagellum that grows externally to the cytoplasmic extension. Posteriorly, a flagellar rotation inferior to 90° occurs and the flagellum becomes parallel to the cytoplasmic extension. Later, the two processes fuse during the so-called proximodistal fusion. The nucleus elongates and moves into the cytoplasmic extension. In the final stage of spermiogenesis, a single crested body appears at the base of the differentiating spermatozoon. Finally, the ring of arching membranes constricts and the young spermatozoon detaches from the residual cytoplasm. Ultrastructural aspects of spermatogenesis are compared with that of other cestodes studied to date, particularly of the family Taeniidae.

9

Influence of 0.02 M EDTA and 3 M KCl on surface of Hymenolepis diminuta and composition of isolated proteins

63%

Machnicka B. , Krawczuk S. , Walski M.

Folia Histochemica et Cytobiologica

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1986

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tom 24

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nr 1

10

Hymenolepididae (Cestoda, Cyclophyllidea) of ciconiiform and pelecaniform birds: the genera Oschmarinolepis Spassky and Spasskaja, 1954 and Paraoschmarinolepis gen. n.

63%

Greben O. , Kornyushin V. , Mariaux J.

Acta Parasitologica

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2017

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tom 62

|

nr 3

11

Transmission of horseradish peroxidase across the tegument of some hymenolepidid species [Cyclophyllidea]

63%

Walski M. , Cielecka D. , Chomicz L. , Grytner-Ziecina B.

Acta Parasitologica

|

1995

|

tom 40

|

nr 4

EN

Strobilae of three hymenolepidid tapeworm species: Diorchis elisae, Fimbriaria fasciolaris and Sobolevicanthus gracilis, obtained from experimentally infected domestic ducks, were incubated for 5,10 and 15 min at a temperature of 38°C, with horseradish peroxidase applied as a tracer by which to research macromolecular transport across the tegument. Through the use of an electron microscope, it was indicated that the marked protein was bound at the surface of the microtriches with the co-participation of glycoproteins of the plasma membrane. It was also shown that the protein molecules gathered at the base of the microtriches were transported in vesicular form inside the syncytial layer and perikaryon part of the tegumental cytoplasm. Molecules of horseradish peroxidase liberated from the vesicles were observed in the excretory system of the tapeworms. In spite of interspecific differences in the structure of the tegument, the tracer protein transmission observed in this research was found to proceed in a similar manner in all the hymenolepidids studied.

12

Ultrastructure of spermiogenesis and mature spermatozoon of Angularella beema [Clerc, 1906] [Cestoda, Cyclophyllidea, Delepididae]

63%

Yoneva A. , Miquel J. , Swiderski Z. , Georgieva K. , Mizinska Y. , Georgiev B. B.

Acta Parasitologica

|

2006

|

tom 51

|

nr 4

EN

The ultrastructure of the spermiogenesis of a dilepidid cestode species is described for the first time. The spermiogenesis of Angularella beema is characterised by absence of both flagellar rotation and proximodistal fusion. The differentiation zone is surrounded by cortical microtubules and is delimited by a ring of arching membranes. It contains two centrioles, one of which develops the axoneme that grows directly into the elongating cytoplasmic protrusion. This pattern of spermiogenesis was described as the Type IV spermiogenesis of cestodes. Among cestodes, similar pattern of spermiogenesis is known in the family Hymenolepididae and in some representatives of the family Anoplocephalidae. The mature spermatozoon of A. beema consists of five regions differing in their ultrastructural characteristics. It is characterised by the presence of cortical microtubules (spirally arranged at angle of 30–40° to the spermatozoon axis) and a single crested body. There is a periaxonemal sheath in certain parts of the spermatozoon as well as glycogen-like granules between the periaxonemal sheath and the cortical microtubules. The comparisons of the mature spermatozoon of A. beema with those of other two dilepidid species (Dilepis undula and Molluscotaenia crassiscolex) demonstrate some variation within the family: presence of periaxonemal sheath in A. beema and D. undula and its absence in M. crassiscolex; presence of electron-dense rods in D. undula and their absence in A. beema.

13

Ultrastructure of oncospheral hook formation in the cestode Mosgovoyia ctenoides [Railliet, 1890] Beveridge, 1978 [Cyclophyllidea, Anoplocephalidae]

63%

Mlocicki D. , Swiderski Z. , Conn D. B. , Eira C. , Miquel J. , Baranowska-Korczyc A.

Acta Parasitologica

|

2005

|

tom 50

|

nr 2

EN

The ultrastructure of oncospheral hook formation in the anoplocephalid cestode Mosgovoyia ctenoides (Railliet, 1890) Beveridge, 1978, is described. The hook morphogenesis takes place inside the six symmetrically arranged hook-forming cells, the oncoblasts. They show characteristic large nuclei of semilunar shape, localized at one pole of the embryo. At the beginning of the hook formation, the "hook-forming centre" appears in the cytoplasmic part of each oncoblast. It consists of numerous free ribosomes and polyribosomes surrounded by several mitochondria and Golgi complexes. The hook-forming centre is involved in synthesis of an electron-dense, undifferentiated hook primordium, which undergoes progressive differentiation and elongation into the fully developed hook. A fully formed oncospheral hook consists of the three parts: blade, shank, and base. Each hook, at the site of its protrusion from the oncosphere, is surrounded by two electron-dense rings interconnected by a circular septate junction. The hook material consists of two or three layers that differ in electron density: (1) a moderately electron-dense core, (2) a middle layer of low electron density, and (3) a highly osmiophilic cortex. Wide bands of hook muscles are attached to the basal and collar parts of the hook. The hook blades project outside of the oncospheral body into a large cavity delimited by the hook region membrane attached at this pole directly to the oncospheral surface. In the fully developed oncosphere of M. ctenoides, the three pairs of oncospheral hooks and their muscles form a complex "hook muscle system", responsible for coordinated hook action. The differentiation and ultrastructure of oncospheral hooks in the oncospheres of M. ctenoides are compared to those described in other cestode species.

14

Ultrastructure of spermiogenesis and mature spermatozoon of Skrjabinoporus merops [Cyclophyllidea, Metadilepididae]

63%

Yoneva A. , Georgieva K. , Mizinska Y. , Georgiev B. B. , Stoitsova S. R.

Acta Parasitologica

|

2006

|

tom 51

|

nr 3

EN

The ultrastructure of the mature spermatozoon and the spermiogenesis of a cestode belonging to the family Metadilepididae is described for the first time. The mature spermatozoon of Skrjabinoporus merops is characterized by twisted peripheral microtubules, the presence of a single crested body, periaxonemal sheath and electron-dense rods, and the absence of intracytoplasmic walls and inclusions (glycogen or proteinaceous granules); no peripheral microtubules where nucleus contacts the external plasma membrane. Four morphologically distinct regions of the mature spermatozoon are differentiated. The proximal part (Region I) contains a single crested body, periaxonemal sheath is absent in some (proximal) sections and is present in others situated closer to the nucleus. The central Region II is nucleated, and is followed by Region III that contains a periaxonemal sheath. The distal pole, Region IV, is characterized by disintegration of the axoneme. Spermiogenesis follows the type III pattern (Bâ and Marchand 1995) although in S. merops a slight flagellar rotation is observed. The differentiation zone is characterized by the absence of striated roots and intercentriolar body; two centrioles are present, one of which gives rise to a free flagellum. The latter rotates and undergoes proximodistal fusion with the cytoplasmic protrusion of the differentiation zone. Spermiological characters of S. merops are similar to those of the families Taeniidae and Catenotaeniidae. The mature spermatozoon differs from those of the Dilepididae (where the metadilepidid species have previously been classified) by the lack of glycogen.

15

Ultrastructure of the spermatozoon of Paroniella reynoldsae [Cyclophyllidea, Davaineidae] an intestinal parasite of Corvus albus [Aves, Corvidae]

63%

Ba C. T. , Ba A. , Marchand B.

Acta Parasitologica

|

2005

|

tom 50

|

nr 3

EN

The mature Paroniella reynoldsae spermatozoon exhibits an apical cone of electron-dense material about 2.2 µm long and 0.65 µm wide at its base and two helicoidal crest-like bodies roughly 100 to 150 nra thick. The latter are of different lengths, spiralled and make an angle of about 45° with the spermatozoon axis. The axoneme is of the 9 + '1' trepaxonematan pattern and does not reach the posterior extremity of the gamete. The nucleus is an electron-dense cord 0.25 µm thick coiled in a spiral around the axoneme. The cytoplasm exhibits a posterior densification and contains few small electron-dense granules in regions I, II and V of the spermatozoon. In regions III and IV, it is divided into irregular compartments by walls of electron-dense material. The cortical microtubules are spiralled at an angle of about 45°. The presence of an electron-lucent apical cone containing numerous small granules of electron-dense material has never, to our knowledge, been reported in a cestode. Likewise, a crest-like body forming a terminal spot of electron-dense material located in the prolongation of the apical cone has never been described before in a cestode. Moreover, in this study, we try to show the existence of tight reciprocal phylogenetic relationships between genera within the Davaineidae and the Anoplocephalidae.

16

Fertilization in the cestode Gallegoides arfaai [Mobedi et Ghadirian, 1977] Tenora et Mas-Coma, 1978 [Cyclophyllidea, Anoplocephalidae]

63%

Swiderski Z. , Conn D. B. , Miquel J. , Mlocicki D.

Acta Parasitologica

|

2004

|

tom 49

|

nr 2

EN

Fertilization in the anoplocephalid cestode Gallegoides arfaai with uniflagellate spermatozoa was examined by means of light and transmission electron microscopy. Fertilization in this species occurs in the oviduct lumen or in the fertilization canal proximal to the ootype, where the formation of the embryonic capsule precludes sperm contact with the oocyte. Cortical granules are not present in the cytoplasm of oocytes of this species. However, two other types of large bodies containing granular material, one of homogeneous moderate electron density and one of heterogeneous moderate electron density, are present in the perinuclear cytoplasm of the oocytes. Spermatozoa coil spirally around the oocytes and syngamy occurs by lateral fusion of oocyte and sperm plasma membranes. In the ootype, one vitellocyte associates with the fertilized oocyte, forming a membranous capsule which encloses both cell types. In this stage, spirally coiled sperm flagella adhere partly to the external oocyte surfaces, and partially enter into the perinuclear cytoplasm. Usually, several loops of the spermatozoon occur within the oocyte cytoplasm. The electron-dense sperm nucleus becomes progressively electron-lucent within the oocyte cytoplasm after entry. Simultaneously with chromatin decondensation, the elongate sperm nucleus changes shape, forming a spherical male pronucleus, which attains the size of the female pronucleus. Cleavage begins immediately after pronuclear fusion.

17

Post-embryonic development and ultrastructural characteristics of the polycephalic larva of Taenia parva Baer, 1926 [Cyclophyllidea, Taeniidae]

63%

Swiderski Z. , Miquel J. , Mlocicki D. , Georgiev B. B. , Eira C. , Grytner-Ziecina B. , Feliu C.

Acta Parasitologica

|

2007

|

tom 52

|

nr 1

EN

Post-embryonic development and fully-formed polycephalic larvae of Taenia parva Baer, 1926 were examined by light (LM) and transmission electron microscopy (TEM). Three developmental stages were recognised: (1) an early stage of exogenous budding at the surface of the central vesicle; (2) a stage of polycephalic cyst development accompanied by segmentation of the growing larval strobile and an obvious decrease in the size of the central vesicle; (3) fully-formed larval strobile and invaginated scoleces. In fully-developed encysted polycephalic larvae, there are usually 14–24 segmented larval strobilae, each terminating with an invaginated scolex; larval strobilae arise from a common central vesicle and remain attached posterior to it during the entire development. The number of segments varies between 109 and 120 per larval strobila. The polycephalic larvae examined closely resemble the strobilocercus type of taeniid larvae. The structure of developing and fully-formed larvae was examined by TEM. The tegument, scolex, subtegumental musculature of the strobilar segments, protonephridial system, calcareous corpuscles and medullary parenchyma of larvae exhibit general similarity with the same structures in adults at both LM and TEM levels. The morphogenesis of the larva of T. parva is compared with that of the polycephalic larvae of other Taenia spp. (T. krepkogorski, T. twitchelli and T. endothoracica) and with other asexually-multiplying cestode larvae (mesocestoidids, hymenolepidids and dilepidids).

18

Oncospheral hook morphogenesis in the cestode Dilepis undula [Schrank, 1788] [Cyclophyllidea, Dilepididae]

63%

Swiderski Z. , Tkach V. V. , Salamatin R. V.

|

tom 45

|

nr 4

EN

Ultrastructural aspects of the oncospheral hook morphogenesis in the dilepidid cestode, Dilepis undula (Schrank, 1788), are described. Oncospheral hook primordia appear within specialised cells, so-called oncoblasts, at the preoncospheral stage of the embryogenesis. Extended Golgi regions, numerous free ribosomes and mitochondria are involved in the hook development. During the hook growth, the blade and base gradually protrude outside the oncoblast plasma membrane. The nucleated oncoblasts persist around the handles of the fully formed hooks even in the mature oncospheres. The mature hooks in the cross-section consist of two to four layers of different electron density, depending on the level of the section; two of them, namely the highly electron-dense cortex and a moderately electron-dense core, are observed in all parts of the hook. A circular, septate desmosome and two electron-dense rings on its both sides are formed around the exits of the hook blades from the oncospheral tegument. Each hook blade has a protective moderately electron-dense “cap” on its tip. A hook region membrane, similar to that described in other cyclophyllideans, forms on the surface of the oncosphere a cavity covering the hook blades. The hook muscle attachment zones at the hook guard and base are represented by a relatively thick layer of fibrous material. The peculiarities of the oncospheral hook formation in Dilepis undula are compared with the results of our previous studies and literature data on other cestodes so far studied in this respect.

19

Drepanidotaenia czaplinskii sp.n. [Cyclophyllidea, Hymenolepididae] a new cestode from Netta rufina [Pall.] [Anseriformes, Anatidae]

63%

Kornyushin V. V. , Tkach V. V.

Acta Parasitologica

|

1995

|

tom 40

|

nr 3

EN

New species Drepanidotaenia czaplinskii sp. n. from Netta rufina (Pall.) (Anatidae) is described and figured. The new species differs from the type species of the genus, D. lanceolata, by longer rostellar hooks (0.055-0.060 in D. czaplinskii vs. 0.030-0.037 in D. lanceolata) and a relatively shorter hook blade, in cirrus size and shape, in cirrus sac size and length of vagina. The narrow interpretation of generic diagnosis of Drepanidotaenia (Spassky and Spasskaya 1954) is supported and only two valid species (D. lanceolata, D. czaplinskii) are recognized in this genus.

20

Ultrastructural study of the spermatozoon of Echinocotyle dolosa [Cestoda, Cyclophyllidea, Hymenolepididae]

63%

Ba A. , Ba C. T. , Marchand B.

Acta Parasitologica

|

2002

|

tom 47

|

nr 2

EN

The mature E. dolosa spermatozoon exhibits an apical disc of electron-dense material about 0.1 µm thick and eight helicoidal crested-like bodies roughly 0.1 µm thick. The latter are of different lengths, spiralized and make an angle of about 40° with the spermatozoon axis. The axoneme is of the 9 + '1' pattern, central in regions I and II, and eccentric in regions III and IV of the gamete. The cortical microtubules are spiralized. The nucleus is a polylobulate compact cord of electron-dense material 0.3-0.7 µm wide, located in parallel to the axoneme and overpassing the posterior extremity. The cytoplasm contains numerous electron-dense granules in regions III and IV, with an increase in electron-density at the posterior end of sperm. The contour of the regions III and IV of the gamete and also that of the nucleus are irregular and polylobulate. This type of polylobulation has never been described in a cestode. Similarly, an apical disc of electron-dense material has never been observed in a cestode spermatozoon; nor has a nucleus of roughly 0.3-0.7 µm in diameter been described in the Cyclophyllidea. In addition, we report for the first time the existence of eight crested-like bodies in a cestode of birds.