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1.
研究对采自青岛沿海的两种海洋纤毛虫-盾圆双眉虫与伪寡毛双眉虫做了形态学重描述。盾圆双眉虫与前人所报道的种群具有十分相似的纤毛图式,但在额-腹棘毛分布、大核片段、小膜及背触毛数目等方面表现出细微的变异性。此外,该青岛种群个体较小。统计学比较还表明,迄今缺乏研究的一海洋种,泥生双眉虫极可能为盾圆双眉虫(Diophrys scutum)的同物异名。伪寡毛双眉虫(Diophrys apoligothrix)为一新近报道的罕见种,研究基于新采集种群对其进行了补充性观察和描述。    相似文献   

2.
Morphogenesis of cell division was investigated in Diophrys scutum, D. oligothrix, and D. appendiculata utilizing both light microscopy of living and stained specimens and SEM of preserved specimens. The cortical morphogenetic pattern of Diophrys is similar to that of other members of the family Euplotidae. The opisthe oral primordium, which develops in a subsurface pouch, forms posterior to the parental buccal cavity. The proter inherits the parental adoral zone of membranelles (AZM) apparently unchanged. The endoral membrane forms to the right of the posterior end of the AZM in the proter, in association with the developing AZM in the opisthe. The paroral cirrus and membrane develop from a single streak that first appears along the right edge of the buccal cavity in the proter to the right of the developing buccal structures of the opisthe. Frontal and transverse cirri develop in both proter and opisthe from five separate cirral primordia that form to the right of the buccal cavity. Left marginal cirri do not develop in association with the corresponding parental structures. Kinetosomes formed within the opisthe oral primordium, or kinetosomes that were part of any parental ciliary structure, do not appear to become part of any developing paroral structures, frontal, transverse, or left marginal cirri. Speciation within the genus Diophrys and evolution of the family Euplotidae as they relate to the morphogenesis of cortical structure are discussed.  相似文献   

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5.
应用光学显微镜和扫描电子显微镜,观察到在一种游仆虫无性生殖周期中,新口围带发育时老口围带的更新、新波动膜原基的发生、棘毛原基发生的最早形态和背触毛发生等在其他种游仆虫中未见报道的现象。  相似文献   

6.
SYNOPSIS. An electron-microscopic investigation of gluaraldehyde-and osmium-vapor-fixed Nyctotherus cordiformis has revealed the following: (1) A thin epiplasmic layer lies directly beneath a single limiting membrane. ( 2 ) The somatic kinetosomes are arranged in approximately 76 parallel rows separated from each other by a vacuolated region 2.4 μ wide. (3) The kinetosomes in each row are paired (both members ciliated), with 7 tubular fibrils (18-21 mμ) originating radially from the right posterior margin of the posterior kinetosome, passing upward and anteriorly as a compact bundle. Also finding their origin in the proximity of the right radial fibrils point of origin are approximately 7 tubular fibrils, extending downward and posteriorly, where they join with adjacent posteriorly directed fibrils. Tangentially arranged tubular fibrils originate from the left anterior margin of both kinetosomes and are directed upward and anteriorly. Dense filamentous material surrounds both kinetosomes and extends laterally towards the adjacent rows. (4) Peculiar, electron-dense, spherical bodies (10-14 mμ) and larger rectangular bodies are present in the lumen of the kinetosomes. (5) A fine filamentous reticulum is present under the double row of kinetosomes of the UM as well as the 100 membranellar units of the AZM. (6) Oral fibrils (18 mμ) in groups of 3 extend upward into the ectoplasmic folds which separate the membranellar units; additional fibrils extend deep into the anterior and posterior ectoplasmic regions. (7) The nemadesmata originate on the right side of the buccal cavity and extend outward to their apparent terminus in the vacuolated ectoplasm.
A brief historical account and results of light-microscopical investigation employing silver impregnation methods are also included as well as a discussion of the anteriorly directed right radial fibrils, deep posterior fibrils and their non-kinetodesmal affinities.  相似文献   

7.
The morphology, infraciliature, and silverline system of a new marine scuticociliate, Dexiotrichides pangi n. sp. were investigated. The new species is characterized by: size about 45-65 x 20-25 microm in vivo with kidney-like body shape and obliquely truncated semicircle-shaped apical plate; cytostome at bottom of conspicuously depressed oral cavity, which is located at the cell equatorial level; paroral membrane extending anteriorly to membranelle 3; scutica multi-rowed; 33-38 somatic kineties; contractile vacuole near ventral side and subcaudally positioned, opening at posterior end of somatic kinety 3; one oval macronucleus and one small micronucleus; caudal cilium positioned in a small pouch; marine habitat. Based on the data obtained, an improved diagnosis for the genus Dexiotrichides is suggested: body with circular cross-section and conspicuous cilia-free apical plate; buccal cavity conspicuously depressed with cytostome located near or at equatorial level; three membranelles transversely orientated each with 2-3 rows; paroral membrane zigzaging structure, extending to about half of the length of buccal field; multi-rowed scutica; somatic kinety one strongly shortened and terminating anteriorly at posterior end of buccal field; basal bodies in equatorial region arranged usually in circular pattern, while in the anterior portion of somatic kinety 2, basal bodies characteristically in pairs and separated from the posterior part of kinety 2; one caudal cilium.  相似文献   

8.
《Journal of Asia》2000,3(1):19-24
Iotonchus onchus n. sp. is characterised by 2.4–2.5 mm long body; buccal cavity with posteriorly placed dorsal tooth at 72–77% of its length, dorsally swollen oesophageal collar, tuberculate cardia, presence of pre- and post-vulval papillae, muscular vagina without sclerotization and males with 11 pre-cloacal ventromedian supplement and 2 post-cloacal ventral papillae. Another species, I. litoralis reported here for the first time from Korea is also described in detail with variations in its buccal cavity length, tooth position and ‘a’ value.  相似文献   

9.
ABSTRACT. The morphology and infraciliature of Orthodonella sinica n. sp. and Apokeronopsis wrighti n. sp., isolated from the coastal water off Hong Kong, were investigated in living and stained specimens. Orthodonella sinica n. sp. is diagnosed as: a marine Orthodonella 150–310 × 40–80 μm in vivo; with a dominant beak-like projection at the anterior end; about 70 somatic kineties; 84–126 dikinetids in the synhymenium; one contractile vacuole in the posterior one-fourth of cell, near the left margin; one conspicuous dorsal suture. Apokeronopsis wrighti n. sp. is diagnosed as: an Apokeronopsis about 150–230 × 35–55 μm in vivo; dark-reddish blood-cell-shaped cortical granules grouped in three rows on the ventral side and two rows on the dorsal side; 23–35 cirri in the right mid-ventral rows (MVR) and 23–32 cirri in the left MVR; six to eight buccal, two frontoterminal, 30–42 left marginal, and 32–43 right marginal cirri; 21–30 transverse cirri extending anteriorly beyond the level of mid-body; consistently three dorsal kineties. The separation of A. wrighti n. sp. and its highly similar congeners Apokeronopsis crassa and Apokeronopsis bergeri was supported by comparison of their SSrRNA gene sequences.  相似文献   

10.
Abstract. Both larval and adult fan worms capture particles with opposed bands of cilia. While the larvae use one of the opposed bands (the prototroch) for both feeding and swimming, the sessile adults rely partly on ambient currents to bring food particles to the ciliary bands. The scaling of length of prototrochal cilia with larval body size contrasts with scaling of the opposed latero-frontal cilia with adult body size. In the larva of the serpulid Hydroides elegans , the length of prototrochal cilia increased from 28 to 42 μm in early to late-stage larvae. In contrast, latero-frontal cilia did not increase in length (23 μm) during postlarval development of H. elegans. Among adults of 5 fan-worm species, lengths of latero-frontal cilia ranged from 22 to 35 μm and were weakly correlated with body size. The total area of ciliary filter nevertheless increased with increasing body dry weight of worms with an allometric exponent similar to exponents reported for gill and lophophore areas vs. body weight within species of suspension-feeding bivalves, brachiopods, and gastropods. The similar scaling was remarkable given the striking differences in distribution and function of the ciliary filters. In adult fan worms, increases in filter area depended largely on increases in number and length of radioles; differences in branching of radioles had little effect. Radioles were commonly in 2 or more rows in series, implying refiltration in still water by downstream radioles. Since the allometry of worms' filter area with body size depends on filters in series, it depends on ambient currents that overwhelm ciliary currents.  相似文献   

11.
SYNOPSIS. A new species of kinetophragminophoran ciliate, collected from dried vegetation and capable of forming an aerial sorocarp, is described and named Sorogena stoianovitchae gen. n., sp. n. This ciliate is a voracious predator that feeds on species of Colpoda , and, when the latter is depleted in numbers, aggregates to forms sorogens. Each sorogen rises into the air from the surface of the water, forming a secreted stalk with a sorus of cysts at its apex. the feeding stage of the ciliate resembles an Enchelys in that it has an apical, slit-like mouth surrounded by a lip, a somewhat dorso-ventrally flattened body, and meridional kineties. Its length ranges from 40–75 μm and width from 23–55 μm. It has a typical rhabdos type of cytopharynx, but no specialized oral ciliature. the somatic kineties are formed of rows of paired kinetosomes with associated microfibrils, the arrangement of which differs a little from that of other ciliates of this subclass. Sorogena has tentatively been placed in the order Haptorida although it lacks toxicysts, recognizable mucocysts, and clavate cilia. Its unique life cycle and some of the details of its fine structure indicate differences between Sorogena and other haptorids so profound that a new family, SOROGENIDAE, is created for it. the type species (PNG76-73) was collected on dry figs at the Wau Ecology Institute, Papua New Guinea.  相似文献   

12.
ABSTRACT. Described herein are the morphology and certain morphogenetic stages of a new freshwater ciliate species, Deviata polycirrata n. sp., and of Deviata bacilliformis recorded in the soil of a dried temporary pond from Argentina. Ciliates were studied alive and after silver impregnation with Protargol. Deviata polycirrata n. sp. measures 130–180 × 45–70 μm in vivo. The species possesses 8–9 long cirral rows on the right and 9–13 on the left of the oral zone, and 3 dorsal rows of dikinetids. The adoral zone is composed of 39–48 membranelles. There are four macronuclear nodules and usually two micronuclei. A single contractile vacuole is located equatorially on the left body margin. This new species mainly differs from its congeners in having a higher number of cirral rows, the three long dorsal rows of dikinetids (vs. usually one to two dorsal rows of dikinetids), and a higher number of adoral membranelles. The other species reported here, D. bacilliformis, is recorded for the first time in Argentina. Unlike previous observations on this species, on the dorsal surface there are cirral rows that are preceded by cilia (combined cirral rows), and stomatogenesis begins with the proliferation of non‐ciliferous basal bodies some distance posterior to the buccal vertex.  相似文献   

13.
The morphology and morphogenesis of a new oxytrichid ciliate, Notohymena limus n. sp. were studied in vivo and after protargol impregnation. The new ciliate was isolated from the sewage sludge at Delhi Jal Board Sewage Treatment Plant located at Rithala, Delhi, India, using the non-flooded Petri dish method. N. limus n. sp. is characterized as follows: flexible dorsoventrally flattened ellipsoidal body; Notohymena-pattern undulating membranes; adoral zone of membranelles (AZM) occupied about 39% of the body length, and consists of around 26 membranelles; large and deep buccal cavity; colorless subpellicular granules present in groups and arranged around the bases of dorsal bristles; 4 macronuclear nodules; 2 micronuclei; 18 fronto-ventral-transverse (FVT) cirri in typical Oxytricha-pattern; 6 dorsal rows of bristles; 3 caudal cirri; about 16 right and 15 left marginal cirri; N. limus n. sp. is a new species on the basis of the combination of morphological, morphometric and morphogenetic characteristic features.  相似文献   

14.
ABSTRACT. The light microscopic and ultrastructural characteristics of a microsporidium provisionally identified as Toxoglugea chironomi (Debaiseux, 1931) Jírovec, 1936, is described. It was isolated from oenocytes and adipose tissue of a midge larva of the genus Dicrotendipes . Merozoites are diplokaryotic. The sporogony produces, by fragmentation, eight monokaryotic spores in a sporophorous vesicle. Mature spores are horse-shoe shaped. The total length is about 5.8 μm, the width 0.8-0.9 μm, the external height of the curve 2.3-3.5 μm, and the external width of the curve 3.5-5.2 μm. The polaroplast has lamellar compartments of two types: narrow and closely packed anteriorly, and wider and more loosely arranged posteriorly. The isofilar polar filament is arranged in 8–10 coils in the posterior fourth of the spore. The external nuclear membrane is sometimes continuous with the endoplasmic reticulum. Lamellar and tubular material of exospore construction are present in the episporontal space from the beginning of sporogony. Teratological and normal spores sometimes occur together in the sporophorous vesicle. The identification of the species is discussed and the ultrastructure is compared to Toxoglugea variabilis , the only further species of the genus with known ultrastructural cytology.  相似文献   

15.
应用蛋白银染色技术研究了悬游双眉虫青岛种群无性生殖期间皮层结构和核器的演化过程,其主要特征为:后仔虫口原基独立地出现于紧靠虫体左侧第一根横棘毛的皮层下小龛,其中毛基粒不参与其它棘毛原基的形成;老的口围带发生后半部的局部重建而非整个的由前仔虫简单继承;在前仔虫中,波动膜原基来自老结构的反分化,而在后仔虫中则来自口原基;所有棘毛原基均为独立发生并与老结构没有任何关系;在前仔虫中,口棘毛(即左侧第一根额棘毛)来自于波动膜的反分化,而在后仔虫中则为独立发生;背触毛列于老的结构当中产生,并由最右一列原基演化出3根尾棘毛;两大核片段的改组带从一端向另一端移动 ,并随着两者的融合而消失.文中同时对前人有关该属发生模式的若干存疑问题做了探讨 [动物学报 54(3):517-524,2008].  相似文献   

16.
The morphology and morphogenesis of Diophrys japonica spec. nov., isolated from the Mie Port, Nagasaki, Japan, were investigated from life and following impregnation with protargol. The new species is recognized by the following characters: Body elliptical in outline and slightly greyish to yellowish in color; size in vivo about 80-120 x 50-70 microm; pellicle flexible, with underlying granules densely arranged in lines; ciliature comprising about 30-46 adoral membranelles, 4-7 frontal, 1-4 ventral and 4-7 transverse cirri, always 1 left marginal and 3 caudal cirri, and 4 dorsal kineties; usually two macronuclear nodules; fragment kinety with 2-5 dikinetids; marine habitat. The main morphogenetic events are: (1) the opisthe's oral primordium develops de novo in a subsurface pouch near the left transverse cirri; (2) the proter retains the parental AZM except for reorganization of some proximal membranelles; (3) cirral anlagen for the frontal, ventral and transverse cirri in both dividers develop separately from the oral primordium or parental cirri, and are derived from the separation of primary primordia that originate de novo; (4) the anlagen for the left marginal cirrus and fragment kinety also form de novo and separately; (5) dorsal kinety anlagen occur within the parental structures at mid-body and posterior end of the cell, of which the right-most one contributes three caudal cirri from its posterior portion. Based on available ontogenetic data, the author proposes that the numbers of left marginal and caudal cirri can be regarded as reliable characters for species identification, while the numbers of frontal, ventral and transverse cirri are not consistent enough for species distinction. A key to the eleven adequately known species of Diophrys is presented.  相似文献   

17.
Leptoamphisiella vermisGruber, 1888 n. g., n. comb. (basionym Epiclintes vermisGruber, 1888) is an extraordinarily large and worm-like marine stichotrichous ciliate. Based on a population isolated recently from coastal waters of Qingdao, China, the living morphology and infraciliature are redescribed and its taxonomic position is defined. Accordingly, a new diagnosis for this species is suggested: large, marine Leptoamphisiella with a conspicuous layer of pellicular alveoli; 400-1000 microm x 40-70 microm in vivo; body band-like, highly flexible; about 40 membranelles; always three frontal and two buccal cirri; 52-80 transverse cirri (TC) extending to the posterior end of the buccal field; 57-79 left midventral and 44-62 right midventral cirri; 62-102 cirri in left and 63-91 cirri in right marginal rows (MR); 9-13 dorsal kineties that extend the full body length; about 100 macronuclear nodules and 5-13 micronuclei. The diagnosis for the new genus is as follows: vermiform Pseudoamphisiellidae with strongly contractile body, differentiated frontal, buccal, and highly developed TC; two remarkably separated midventral rows; one MR on each side of the body; frontoterminal and caudal cirri absent. Leptoamphisiella vermis n. comb. is fixed as the type species of the new genus.  相似文献   

18.
Sphaerospora epinepheli n. sp. is described from grouper, Epinephelus malabaricus , in cage-cultured and wild fish collected from both coastal lines of southern Thailand. Subspherical to spherical spores and mono- or disporous pseudoplasmodia were observed in the lumen of kidney tubules. Pseudoplasmodia were round to elongate, size range 15.6–22.9 μm (length) × 8.4–21.6 μm (width). Spores were 7.8–10.0 μm (length) × 12.3–14.5 μm (thickness), and 7.0–9.5 μm (width) with two spherical polar capsules of equal size measuring 2.9–4.4 μm in diameter and containing polar filaments with six or seven windings. Two uninucleate sporoplasms showed iodine vacuoles. Blood stages, similar to C-blood protozoans observed from freshwater fish in Europe, were found from peripheral blood smears of grouper. Ultrastructural studies of blood stages showed a similar structure to unidentified mobile protozoans from the blood of carp. Electron dense bodies were observed in the cytoplasm of the primary cell blood stages. Infected proximal-tubular epithelial cells showed highly vacuolated cytoplasm and pycnotic nuclei.  相似文献   

19.
ABSTRACT. Species belonging to the genus Diophrys Dujardin, 1841, are easily recognized due to possession of the usual complement of approximately seven frontoventral cirri, five transverse cirri, two left marginal cirri, and three large caudal cirri. Separation of these species has been based upon differences in cell length and width, the number and arrangement of cilia in dorsal kinetics, the configuration of the adoral zone of oral polykinetids, the number and distribution of cirri within cirral groups, and the number and arrangement of macronuclei. Jankowski used some of these characteristics to divide the genus into two genera, Diophrys and Paradiophrys, with several subgenera [Jankowski, A. W. 1978. Systematic revision of the class Polyhymenophora (Spirotricha), morphology, systematics and evolution. Tezisy Dokl. Zool. Inst. Akad. Nauk SSSR, 197839-40. (in Russian); Jankowski, A. W. 1979. Systematics and phylogeny of the order Hypotrichida Stein, 1859 (Protozoa, Ciliophora). Trudy. Zool. Inst. Akad. Nauk SSSR, 86 :48–85. (in Russian with English summary)]. Data obtained from light microscopic examination of stained (nigrosin-butanol, Chatton-Lwoff, and Protargol) cells in interphase or division supports and modifies the use of particular structural features of these ciliates for the purpose of taxonomic classification. The structural variability within and among populations of different species within the genera Diophrys (D. appendiculata, D. oligothrix, and D. scutum) and Paradiophrys (P. irmgard and P. multinucleata) is described. D. hystrix is redescribed as the type of the new genus Diophryopsis n. g. Comparative information on the cortical morphogenesis of division of selected species within each genus is reviewed. Two taxonomic classifications of these hypotrichs are discussed: 1) a listing of diagnoses and synonymies and 2) a binary key for identification of all species at the light microscope level. An alternative evolutionary explanation of variations among isolates is presented.  相似文献   

20.
Three species of Diophrys, D. peculiaris nov. spec., D. cf. scutum and D. oligothrix, isolated from the New Nagasaki Fishing Port, Nagasaki, Japan, were investigated using live observation and protargol impregnation. Diophrys peculiaris nov. spec. can be recognized by having two characteristic clusters of rod-like structures and two groups of dikinetids located on anterior dorsal portion of cell. Morphogenetic data show that this part of the life cycle basically proceeds as in congeners, except for the formation of dikinetids under the rod-like structures. In the opisthe, the origin of dikinetids under the rod-like structures is still unknown, but the old dikinetids under the rod-like structures may be retained by the proter. The Japanese population of Diophrys cf. scutum resembles other populations of D. scutum well except for moniliform macronuclear segments. Our populations of D. oligothrix correspond well with other populations in terms of general morphology and ciliary pattern, in particular the continuous dorsal kineties with loosely arranged cilia.  相似文献   

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