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1.
SYNOPSIS. A new apostome ciliate was discovered in collections at Friday Harbor, Washington and the San Francisco area. All stages of the life cycle were studied in both living and stained condition. Dormant encysted stages (phoronts) occur on the gills of Pagurus hirsutiusculus. Excystation occurs in synchrony with the molting of the host yielding the trophic stage (trophont), which feeds on the exuvial fluids trapped in the crab's cast-off exoskeleton. The trophont becomes greatly enlarged as a result of feeding, and the cytoplasm and organelles become compressed into a thin cortical layer. Each fully grown trophont encysts (becoming a tomont) as a prelude to repeated binary fission, which results in the release of actively motile offspring (tomites). These disperse and promptly resume the encysted phoront stage on the host's gills. The Chatton-Lwoff silver impregnation method revealed that all stages of the life cycle have nine somatic kineties. In the trophont stage they are accompanied by an anterior ventral field of scattered clumps of kinetosomes. During conjugation the partners attach by their ventral surfaces between kineties 1 and 9 and at the left of the ventral field. The tomite stage was stained with Protargol. In addition to the characteristic features of the foettingeriid tomite also revealed by the Chatton-Lwoff method, Protargol revealed the following heretofore undescribed morphological features: a short row of kinetosomes immediately anterior to the ogival field; a line paralleling the left margin of the field; the continuity of kinety 8 with falciform field 8; the entrance of kinety 9 into the mouth and its ending against the rosette (an enigmatic organelle characteristic of Foettingeriinae). Feulgen stains showed that the chromatin in the macronucleus is dispersed in aggregates whose size and number vary with the stage of the life cycle. The major period of chromatin synthesis appears to be during the early tomont stage, when Feulgen-positive material increases visibly in amount and intensity of staining. This apostome ciliate was characterized as a new genus on the basis of the infraciliature of the trophont stage, its conjugation with ventral surfaces appressed, and its life cycle. It is named Hyalophysa (hyalo = glassy, physa = bubble) chattoni.  相似文献   

2.
SYNOPSIS The cortical infraciliature of Kuklikophrya dragescoi gen. n., sp. n. is composed of double kinetosomes. Each kinetosome has transverse fibers. The anterior transverse fibers are associated with a sheet of dense material and the posterior transverse fibers are directed toward the posterior part of the body. The posterior kinetosome of a pair has only a short protuberance in the position of the kinetosomal fiber. The cortex has a well developed alveolar layer and a thick ecto-endoplasmic boundary. A distinctive characteristic of the buccal ciliature is the circumoral ciliature whose infraciliature is made up of pairs of cilia-bearing kinetosomes. The antero-posterior polarity of the paroral segment is in inverse relationship to that of the remaining ciliature of the organism. The adoral and preoral ciliary organelles consist of 2 rows of kinetosomes, each of which bears postciliary fibers. A frame of nematodesmata surrounds the cytopharynx which is supported by microtubular bands which impart to it a very specific laminated appearance. The “phagoplasm” is formed by “vermicelli”-like vesicles. The micronucleus is found in the perinuclear area of the macronucleus.  相似文献   

3.
SYNOPSIS. Morphogenesis, and the cortical structures of Brooklynella hostilis, a cyrtophorine gymnostome ciliate ectoparasitic on marine fishes, were studied from protargol silver-impregnated preparations and with the aid of electron microscopy. The pattern of morphogenesis of Brooklynella is close to that found in less differentiated species of the families Chlamydodontidae (e.g., in the genus Trithigmostoma) and Dysteriidae (e.g., in the genus Hartmanula). The full number of kineties in the opisthe is restored after division from a segment of the left one of the 3 kinetics producing the oral rows. The oral rows consist of a double row of kinetosomes arranged in a zig-zag pattern; only the outer row is ciliated, the inner one being barren. However, the positions of the postciliary and transverse fibers indicate that the oral rows are not homologs of an undulating membrane but are akin to a membranelle. In association with the ventral somatic kinetosomes there are 4 postciliary fibers; a rather aberrant, transversally oriented kinetodesma; 2 microtubular, transverse fibers plus a transverse fibrousspur; and one to several ribbons of subkinetal microtubular fibers. Not directly associated with the kinetosomes are fibrous strands running subpellicularly between the kinetosomes and also deep into the cytoplasm. The cortical structures of Brooklynella are compared with those of some other groups of ciliates of about the same phylogenetic level in which the subkinetal microtubules can also be found– rhynchodine, suctorian, and chonotrich ciliates. The nasse consists of 6–8 nematodesmata not closely associated with the microtubular cytopharyngeal tube. The former have a distinctly developed densely fibrous capitulum containing barren kinetosomes which originally produced the nematodesma during stomatogenesis; the capitulum is connected by a fibrous link to the microtubular shaft. Extending from the oral rows to the capitula are fibrous structures strongly reminiscent of filamentous reticulum in hymenostome and peritrich ciliates. The structure of the posterio-ventral glandular organelle is also described and discussed.  相似文献   

4.
Three ciliate species from Australia and Norway were examined by silver impregnation, biometry, and scanning electron microscopy. Trochiliopsis australis n. sp. (order Nassulida, family Microthoracidae) differs from the single other known species of the genus, T. opaca, by its prominent ridges on the left side, the distinctly longer anterior segment of somatic kinety 2, and by the doubled total number of kinetosomes. Pelagohalteria n. g. (order Oligotrichida, family Halteriidae) differs from Halteria by the structure of the bristle complexes, which are composed of a vertically and a horizontally oriented row of kinetosomes. Two Halteria species belong to the new genus: P. viridis (Fromentel, 1876) n. comb., which is redescribed here, and P. cirrifera (Kahl, 1935) n. comb. Strobilidium lacustris n. sp. (order Oligotrichida, family Strobilidiidae) differs from its nearest relative, S. velox, by the smooth pellicle, the absence of symbiotic green algae, and by its larger size.  相似文献   

5.
ABSTRACT. Morphological and ultrastructural studies on a new ciliate, Paraptychostomum almae , from the digestive tract of an oligochaete ( Alma emini ) from the Cameroons are carried out. The flattened cell has a large size; its left lateral face bears an anterior thigmotactic zone that includes seven-nine short kinetal segments. The somatic cortex is composed of flattened alveoli, a thin epiplasm and a microfibrillar ecto-endoplasmic boundary. Kineties are made of monokinetids, each particularly characterized by a long anteriorly directed kinetodesmal fiber, and a hyperdivergent postciliary ribbon. The postero-ventral buccal apparatus consists of a short peristome and a deep longitudinal infundibulum. The paroral organelle is a long stichodyad. The three adoral organelles are of different types: ADI and AD3 are of the membranoid type, respectively with two and one rows of ciliated kinetosomes; AD2 is of the peniculus type with six-seven rows of ciliated kinetosomes. A microfibrillar network with nodes arises from all the buccal kinetosomes and extends under the naked wall. Mitochondria are small and numerous and dispersed throughout the whole cell. The existence of an AD2 with more than two rows of kinetosomes warrants the creation of the new genus Paraptychostomum and a new family, Ptychostomatidae. The presence of a distinct ecto-endoplasmic boundary and of somatic kinetids exclusive without transversal dense tractus, hyperdivergent postciliary ribbons, and dispersed numerous mitochondria, added to particularities of the stomatogenesis, allow us to clearly separate hysterocinetians from the scuticociliates and to set up for them the new subclass Hysterocinetia, within the class Oligohymenophorea, with a single new order Hysterocinetida.  相似文献   

6.
RESUME. Chacun des 45–80 organelles adoraux de Bursaria truncatella O. F. Müller est constitué de 3 rangées de cinétosomes et l'aire buccale droite est couverte de nombreuses doubles rangées de cinétosomes. La stomatogenèse débute par la désorganisation et la résorption des organelles buccaux postérieurs. Puis, il y a désorganisation des rangées parorales de cinétosomes et multiplication des cinétosomes sur l'aire orale droite, en měme temps que sont rompues, selon une ligne oblique, un certain nombre de cinéties somatiques. La prolifération des cinétosomes aux extrémités des cinéties. de part et d'autre de la ligne de rupture, aboutit, d'une part, à la formation d'un champ anarchique qui est le primordium oral droit de l'opisthe, d'autre part, à la formation de nombreux doublets qui constituent chacun le primordium de chaque organelle adoral. Après la séparation des tomites, les cinétosomes de l'aire droite s'ordonnent en doubles rangées et les organelles adoraux se complètent par addition d'une 3ème rangée de cinétosomes. Les cinétosomes somatiques sont jumelés, reliés par 2 desmoses. Les fibres transverses postérieures et les fibres postciliaires forment de longs rubans de microtubules dirigés vers l'arrière et juxtaposés dans les crětes intercinétiennes. Les doubles rangées droites de cinétosomes buccaux sont assimilables à des stichodyades. Les organelles des cinétosomes adoraux portent des rideaux de fibres postciliaires convergents ou divergents. La rangée postérieure de chaque organelle est non ciliée. Par son type de stomatogenèse, par sa structure corticale, par l'ultrastructure des organelles adoraux, Bursaria appartient aux Colpodidea, ce qui suggère des remarques de plusieurs types. SYNOPSIS. In Bursaria truncatella O. F. Müller, each of the 45–80 adoral organelles is composed of 3 rows of kinetosomes, and the right buccal area is covered by many double rows of kinetosomes. Stomatogenesis begins by disorganization and disappearance of the posterior buccal organelles. Next, there is disorganization of the paroral rows of kinetosomes and multiplication of kinetosomes in the right oral area; at the same time, some somatic kineties are disrupted along an oblique line. Multiplication of kinetosomes at the extremities of the kineties, on both sides of the disruption, leads to the formation of an anarchic field which is the right oral primordium of the opisthe and the formation of doublets each of which constitutes an adoral organelle. After the separation of the tomites. the kinetosomes in the right buccal area position themselves, and the adoral organelles are completed by the addition of a 3rd row of kinetosomes. Somatic kineties are formed by successive pairs of ciliated kinetosomes united by 2 desmoses. the long posterior transverse ribbons and the postciliary ribbons extend posteriad, overlapping in the pellicular ridges. Oral rows of kinetosomes on the right can be compared with stichodyads. the adoral kinetosomes have convergent or divergent postciliary ribbons. the posterior row of kinetosomes in each organelle is not ciliated. By the type of stomatogenesis, the cortical ultrastructure, the ultrastructure adoral of its organelles, Bursaria belongs to the Colpodidea.  相似文献   

7.
SYNOPSIS Cortical events occurring in the course of regeneration in Condylostoma magnum (Spiegel) were studied by electron microscopy. The zone of regeneration is very rich in vacuoles and small vesicles formed from the plasma membrane. Multiplication of kinetosomes starts on the left side of kineties in the V-shaped left ventral area, normally implicated in stomatogenesis, at the level of the anterior kinetosomes of the somatic pairs. The proliferation proceeds by the appearance of young kinetosomes most often orthogonal to the old ones. This process of multiplication is very rapid and terminates in the formation of an “anarchic field” in which one observes that: (a) the newly formed kinetosomes do not possess all the associated postciliary fibers; and (b) when these fibers are detected, the kinetosomes are not in the same orientation. Differentiation of the adoral organelles takes place in the left part of the field (left primordium) by an alignment of the kinetosomes into 2 rows for each organelle (oriented perpendicularly to the antero-posterior axis of the ciliate), of which only one has the postciliary fibers. Ciliatogenesis occurs in numerous kinetosomes of the anarchic field; in certain kinetosomes it is achieved at the onset of their arrangement into organelles and is concomitant with growth of the nematodesmata. The 3rd (anterior) row of the organelles, the interkinetosomal desmata, and connections among neighboring organelles appear only secondarily. Differentiation of the paroral cilia occurs later. It takes place in the interior of the primordium, whose organization is primarily anarchic, and is accompanied by a progressive resorption of the major part of the newly formed kineties. Numerous kinetosomes of the right field have the associated postciliary fibers, which are not found at the level of the regenerated “polystichomonad” (paroral organization characteristic of C. magnum). Finally, the formation of new kinetosomes within a somatic kinety at the time of its elongation is described.  相似文献   

8.
A new genus and species combination are proposed for Urocryptum tortum n. gen., n. comb., a scuticociliate with a polymorphic life cycle. This marine ciliate was isolated from a sample taken at Gokasho Bay in Mie Prefecture (Japan). Specimens from different phases of the growth cycle were examined in vivo and with two silver staining techniques. Three life-history stages were observed: an exponential growth phase stage (trophont), a stationary phase stage (tomite), and finally a resting stage (cyst). The exponential growth form is laterally flattened and ovoid; it has 20-24 somatic kineties (SK) and a typical complement of scuticociliate oral structures. Polykinetid 1 (Pk1) has two longitudinal files of 6 kinetosomes (Ks); sometimes one or two additional kinetosomes are located anteriorly. Polykinetid 2 (Pk2) has two files of 6 or 7 Ks; a third file of three widely spaced kinetosomes is located on its right side, as well as a small curved row of 5 Ks positioned on the right hand side of the posterior end of Pk2. Polykinetid 3 (Pk3) has 3 rows of 4, 5, and 7 Ks's perpendicular to the haplokinety (Hk) or paroral membrane. The stationary growth phase cell is spindle-shaped and has a similar number of SK that are much more closely spaced than in exponentially growing specimens. Oral infraciliary structures are reduced in size, having fewer kinetosomes and being positioned more anteriorly in the cell. Pk1 is composed of two files of 5-Ks, Pk2 has only two files of 6-7 Ks, and Pk3 has two to three rows of 3-4 Ks. The Hk is displaced anteriorly and becomes straight, losing the shape typical of exponential growth phase cells. Cysts are pyriform with a wide cyst wall; no infraciliary structures were visible.  相似文献   

9.
The morphology and morphogenesis of the kinetofragminophoran soil ciliates, Fuscheria terricola n. sp. and Spathidium muscorum Dragesco & Dragesco-Kerneis, 1979, are described. Stained specimens (protargol) are characterized biometrically. The new species differs from the other species of the genus in its body size, body shape, number of kineties, length of extrusomes, and habitat. Both species have telokinetal stomatogenesis, which commences with a proliferation of kinetosomes at those kineties which bear the brosse. Fuscheria terricola does not have a complex perioral ciliature; indeed, it might be that this species has only monokinetids. Thus only a proliferation of kinetosomes and the separation of the kineties takes place in the prospective division furrow. In contrast, S. muscorum differentiates short dikinetid kinetofragments in the region of the division furrow, which are arranged to form the perioral kinety of the opisthe in the intermediate and late stages of the stomatogenesis. The right part of the perioral kinety develops first. This and other studies show that telokinetal stomatogenesis proceeds very differently depending on the differentiation of the oral ciliature; however, detailed studies on the morphogenesis of kinetofragminophoran ciliates are still too few in number for subtypes to be defined.  相似文献   

10.
SYNOPSIS. Monocercomonas shares many fine-structural features with all other trichomonads. These include the basic arrangement of the kinetosomes as well as of the recurrent and 3 anterior flagella. The pelta-axostyle complex and the parabasal apparatus, i.e. the Golgi complex and the periodic filaments, also conform to the trichomonad pattern. Of interest with regard to the crucial evolutionary position of Monocercomonas, considered to represent the most primitive trichomonad type, is the fact that it has some structures in common with other Monocercomonadidae and Trichomonadinae and others in common with Devescovinidae and Tritrichomonadinae. Among the former organelles are the marginal lamella and the costal base, and among the latter, the comb-like organelle situated between the infrakinetosomal body and parabasal filament 2 as well as the infrakinetosomal body. No traces of either costa or undulating membrane have been noted, but a complex structure homologous to the marginal lamella of Hypotrichomonas and Trichomonadinae is found underlying the short anteriormost portion of the recurrent flagellum that is attached to the body surface. Observations of sections of selected division stages indicate the potential of parental kinetosomes #1 and #3 to become daughter kinetosome #2.  相似文献   

11.
SYNOPSIS. A previous study with P. de Puytorac on O. bacterocaryon(3) has shown the methods of studying this Ciliate and has specified the general and buccal morphology, the morphogenesis, and the biology of vegetative individuals (theront, trophont, tomont, tomites) of this species. Three species we are describing now offer numerous common features with O. bacterocaryon. We consider them as the proper characters of genus Ophryoglena and we only insist on the specific particularities of O. gelifera, O. mucosa and O. multimicronucleata. O. gelifera is a large Ophryoglene differing from the others by a slightly asymetric, curved, spindle-shaped theront; the ellipsoidal tomont secretes abundant and clear jelly. The theront possesses one thick spindle-shaped macronucleus, one voluminous spherical micronucleus, fitting with the macronucleus. Its somatic infraciliature is dense, its buccal infraciliature is characteristic, especially in the shape of peniculus P1. This species cannot be mistaken for O. pectans Mugard(2) although it is rather near it. O. mucosa is a very small Ophryoglene. The theront has one thick elliptical macronucleus, one small micronucleus; the buccal orifice is not kidney-shaped, but quite pointed in front; there is no tragus; the somatic infraciliature is not close; the peniculus P1 is characteristic. The tomont is ellipsoidal and surrounded by a thick mucous gangue. The tomites are not close together. O. mucosa is very different from O. gelifera and O. pectans Mugard(2). O. multimicronucleata. Near to O. polymicrocaryon Mugard(2), this Ophryoglene differs from it by the small size of all its vegetative elements and especially by its nuclear-apparatus. The latter includes numerous (5 to 6) bulky spherical micronuclei and one macronucleus looking like blackpudding which can be compared to that of O. singularis Canella and Trinchas(1). The theront is spindle-shaped and of a dark-grey colour. The spherical tomont secretes a mucous gangue which is not very thick. Besides, the somatic infraciliature and buccal in fraciliature of the theront (peniculus P1 especially) make O. multi micronucleata quite distinct from O. polymicrocaryon Mugard(2).  相似文献   

12.
Three new genera of trypanorhynch cestodes are described from Australian elasmobranchs: Cetorhinicola acanthocapax n. g., n. sp. from Cetorhinus maximus (Gunner, 1765), with four bothridia joined by avelum, a typical heteroacanthous armature with the ends of the hook rows not meeting on the external surface, and enlarged hooks on the base of the tentacle; Shirleyrhynchus butlerae n. g., n. sp., from Dasyatis fluviorum Ogilby, 1908 and D. sephen (Forsskal, 1775), with four bothridia, typical heteroacanthous armature, enlarged basal hooks, testes in linear rows, and lacking seminal vesicles; Stragulorhynchus orectologi n. g., n. sp., from Orectolobus tentaculatus (Peters, 1864) (type-host), O. maculatus (Bonnaterre, 1788) and O. ornatus (de Vis, 1882), with four bothridia, poeciloacanthous armature, with a band of hooklets on the external surface of the tentacle, external seminal vesicle, hermaphroditic duct, accessory seminal vesicle and post-ovarian testes. None of the new genera is readily accommodated by the existing classification of the Trypanorhyncha: the first two genera are tentatively allocated to the Gilquiniidae and the last to the Gymnorhynchidae.  相似文献   

13.
Summary Seven species of cestodes and two of nematodes are reported from Phoeniconaias minor from Lake Nakuru, Kenya. Phoenicolepis nakurensis n.g., n.sp. (Hymenolepididae) is characterized by the size and shape of the hooks, scolex and strobila, structure of the terminal genital ducts, presence of an accessory sac, external seminal vesicle and stylet, and absence of an internal seminal vesicle. Gynandrotaenia stammeri. Cladogynia phoeniconaiadis, Flamingolepis tengizi, F. dolguschini and Striatofilaria phoenicopteri are redescribed; all except C. phoeniconaiadis are new for this host and for Kenya. ac]19800210Abbreviations as accessory sac - c cirrus - cs cirrus sac - esv external seminal vesicle - g gland cells - gs glandular sheath - isv internal seminal vesicle - md muscular duct - Mg Mehlis' gland - o ovary - pg prostate gland cells - s stylet - sr seminal receptacle - u uterus - v vagina - vd vas deferens - vg vitelline gland  相似文献   

14.
ABSTRACT. Based on both morphological and molecular information, two new euplotid genera Apodiophrys n. g. and Heterodiophrys n. g. are described in the present paper. Apodiophrys n. g. is defined as sculptured Diophryinae with bipartite adoral zone; frontoventral cirri arranged in Diophrys‐pattern; marginal cirri located in two clearly separated groups. Heterodiophrys n. g. is recognizable by the combination of Diophrys‐like frontoventral cirri and the unique structure of several marginal cirri that are arranged in a long row. The type species for both new genera, Apodiophrys ovalis n. sp. and Heterodiophrys zhui n. sp., collected from southern China sea, are described. The small subunit rRNA (SSU rRNA) gene sequences for both new taxa are determined. Phylogenetic analyses based on these data indicate that Apodiophrys is most closely related to Paradiophrys, which then clusters with Uronychia species. Thus, Apodiophrys–Paradiophrys is separated from other typical Diophrys‐like genera in the SSU rRNA gene trees. The new genus Heterodiophrys is basal to the sister group of Diophrys–Diophryopsis, hence belongs to the “core”Diophrys‐complex.  相似文献   

15.
16.
Synopsis. Structure, infraciliature, and ecology of 4 fresh-water Tintinnina were investigated. The lorica of Tintinnidium fluviatile is gelatinous, fragile, and contains some agglutinated material mainly of biologic origin. Its infraciliature consists of ? 10 kineties. with kinetosomes arranged in pairs. Only one basal body of a pair is ciliated, except for the uppermost 1–4 pairs which have 2 slightly elongated cilia. In Tintinnidium fluviatile. Tintinnidium pusillum, and Tintinnopsis cylindrata there are 2 prominent ventral organelles. The lorica of T. pusillum is gelatinous and coated with much agglutinated material of biologic and nonbiologic origin. Its infraciliature is similar to that of T. fluviatile, but the uppermost pair of kinetosomes has elongated cilia. The firm loricae of T. cylindrata and Codonella cratera are, built mainly of sharp-cornered structures. The infraciliature of T. cylindrata is composed of ? 10 kineties with kinetosomes not arranged in pairs. The infraciliature of C. cratera consists of ? 32 kineties, in some of which the kinetosomes are paired, e.g. ventral kinety, and in others not paired, e.g. cilia of the very prominent lateral field and of the other somatic kineties. The uppermost kinetosomes of each somatic kinety are paired and have elongated cilia. In addition, there is an unusual ventro-lateral kinety. The oral apparatus consists of adoral membranelles and a paroral membrane. The membranelles that enter the praecral cavity are very elongate, a feature perhaps unique to Polyhymenophora. The fibrillar system consists of a prominent praeoral ring formed by fibrils extending from the adoral membranelles. A finely meshed silverline system extends over the entire cell. A review of the ecology of the fresh-water Tintinnina indicated that water temperature seems to be the most essential ecologic factor. The systematic position of the Tintinnina is discussed in light of their infraciliature. It is concluded that these organisms are most closely related to Oligotrichina, and probably to Heterotrichina.  相似文献   

17.
On the basis of a review of the approximately 4300 species of apicomplexan protozoa, the following new species, new names, new combinations, and emendations are given: NEW GENUS,Erhardovina; NEW SPECIES,Ascogregarina polynesiensis, Eimeria golemanskii, Isospora tamariscini; NEW NAME,Gregarina kazumii; NEW COMBINATIONS,Ascogregarina brachyceri (Purrini, 1980),Erhardovina euzeti (Lipa, 1981),E. scutovertexi (Erhardová, 1955),Haemorhormidium batrachi (Chaudhuri & Choudhury, 1983); EMENDATIONS,Selenidium francianum(Arvy, 1952) Tuzet & Ormières, 1965,Pyxinioides bolitoides D. P. Henry, 1938,P. japonicus H. Hoshide, 1951,P. kamenote H. Hoshide, 1951,P. kurofuji H. Hoshide, 1951,P. oshoroensis H. Hoshide, 1951,P. pugetensis D. P. Henry, 1938, Gregarina levinei Haldar & Sarkar, 1980,Retractocephalus halticae Haldar, Chakraborty & Kundu, 1982,Cnemidospora schizophylli Tuzet & Guerin, 1947,Grebneckiella indica (Merton, 1911) Watson, 1916,Quadruspinospora atractomorphae Haldar & Chakraborty, 1978,Haemogregarina acipenseri Nawrotzky, 1914,H. lobianci Yakimov & Kohl-Yakimov, 1912,H. yakimovikohlae Wladimiroff, 1910,Hepatozoon luehi (Sambon, 1909) Pessoa, Cavalheiro & de Souza, 1970,Eimeria beyerae Ovezmukhammedov, 1977, E. (?) gigantea (Labbé, 1896) Reichenow, 1921, E. (?) labbei Hardcastle, 1943, E. rufi Prasad, 1960, E. (?) scylii (Drago, 1902) Levine & Becker, 1933, Isospora corvi Ray, Shivnani, Oommen & Bhaskaran, 1952,I. melopsittaci Bhatia, Chauhan, Arora & Agrawal, 1973, I. seicerci Ray, Shivnani, Oommen & Bhaskaran, 1952,I. stomatici Chakravarty & Kar, 1944,I. triffitae Nukerbaeva & Svanbaev, 1973,Wenyonella mackinnonae Misra, 1947,Octosporetla sanguinolentae Ovezmukhammedov, 1975,Lankesterella millani Alvarez Calvo, 1975,Sarcocystis woodhousei Dogel', 1916,Haemoproteus lari Yakunin, 1972, Babesia ninakohlyakimovae (Yakimoff & Shokhor, 1916),Theileria ninakohlyakimovae (Yakimov, 1916) Krylov, 1974,Haemohormidium batrachi(Chaudhuri & Choudhury, 1983).  相似文献   

18.
19.
SYNOPSIS. The nature and sequence of changes involved in the metamorphosis of the phoront of Hyalophysa have been examined in the light microscope using both living and silver-impregnated ciliates. The phoront's infraciliature, which resembles that of the migratory tomite, differentiates to the trophont (feeding stage) infraciliature without an intervening dedifferentiation. The primary visible event of metamorphosis is the growth of the metastomial area that distorts the meridional somatic kineties so that they curve or spiral around it. The distinct borders and intense argentophilia of the metastomial area suggest that it is a discrete organelle which is probably involved in the management and concentration of a large volume of dilute food. The anterior ventral field of kinetosomes, whose presence distinguishes Hyalophysa from Gymnodinioides, forms from a disorganized anterior segment of falciform field 9. The rapid and pronounced elongation of the somatic kineties supports our view that the kinetodesmos elongates by the sliding of its component subfibrils upon one another, and that the accessory kinetosomes seen in the electron microscope become functional at metamorphosis. The movement of the kineties and contractile vacuole pore during metamorphosis suggests that differentiation in this instance is not directed by pellicular “fields” but by morphogenetic movements of the underlying cytoplasm.  相似文献   

20.
Jon L. Norenburg 《Hydrobiologia》1993,266(1-3):203-218
Riserius pugetensis gen. n., sp. n. is described from the northwest coast of Washington, U.S.A. It is probably a heteronemertine and, as such, would be the first known mesopsammic member of that order; it lives in the interstices of medium to coarse, moderately clean sands. Its morphology presents some attributes considered characteristic of mesopsammic fauna. The effect of some of these attributes is a generalized appearance of anatomical ‘simplicity’ and, as with other mesopsammic metazoans, this presents difficulties in distinguishing between primitiveness and reduction. In the new species such problematic features include the lack of subepidermal glandular cells and connective tissue, reduced proboscideal musculature, simple blood-vascular system, and the presence of a ‘secondary’, outer circular musculature in the body wall. The general appearance of this new species is very similar to the so-called palaeonemertine Hubrechtella and characteristics of both suggest relationship with the baseodiscid heteronemertines. These relationships are explored in light of a modified interpretation of proboscideal musculature, a traditional cornerstone of heteronemertmean taxonomy.  相似文献   

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