The Cortical Morphogenetic Cycle Associated with Cell Division in Diophrys Dujardin, 1841 (Ciliophora,Hypotrichida)1

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.     

Morphogenesis in Conchophthirus curtus: a Study of the Morphological Events Associated with Binary Fission1

Morphogenesis in Conchophthirus curtus has been investigated by the use of protargol silver impregnation supplemented by selective use of scanning electron microscopy. Events are assigned to nine sequential stages; the last, stage 9, which involves maturation of the somatic ciliature and infraciliature as well as the final development of the buccal cavities of both proter and opisthe, occurs following cytokinesis. Stomatogenesis involves both the parental haplokinety and the deep kinetosomal unit (DKU). In perhaps a unique phenomenon, phylogenetically, the ciliated parental haplokinety forms the early oral primordium of the opisthe and is replaced in the proter by the DKU. The DKU then acts as a formative center for new kinetosomes that migrate into the developing opisthe primordium. Late in the process, the haplokinetal primordia of both proter and opisthe give rise to their respective DKU's. Some events of nuclear activity and somatic development are also described. The high degree of structural differentiation of this ciliate has provided the opportunity to examine temporal relationships during morphogenesis. We have found that somatic, buccal, and nuclear events proceed in a tightly coupled sequence. Hence, somatic and nuclear development can be directly correlated with the nine stages of stomatogenesis.     

Morphologie und Morphogenese des Bodenciliaten Oxytricha granulifera sp.n. (CiIiophora, Oxytrichidae)

Oxytricha granulifera sp.n. differs from other members of the genus by its subpellicular granules and the strongly shortened dorsal kinety 4. The overall pattern of the morphogenetic events is similar to that known from other Oxytrichidae. However, the oral primordium evolves de novo between the left marginal cirral row and the postoral cirri. The six anlagen of the frontoventral cirri are of different origin. Two anlagen of the proter evolve from parental frontal cirri, two from the opisthe, and one includes basal bodies of the proter and opisthe. Two anlagen of the opisthe evolve from the oral primordium, and three primordia originate from the postoral cirri. Frontal cirrus 1 evolves from the paroral membrane in the proter, and from the oral primordium and the anlagen of the frontoventral cirri in the opisthe. The genus Oxytricha can be subdivided into several groups with regard to the origin of its oral primordium and the development of the frontoventral cirri. The morphogenesis of the dorsal kineties in the Hypotrichida is reviewed. Seven different modes of origin are distinguished. We conclude that morphogenetic features cannot be used in the classification of the Hypotrichida at the generic level, because we have too little information to decide whether special morphogenetic features are important at the generic or species level.     

Uronychia transfuga (O. F. Müller, 1786) Stein, 1859 (Ciliophora, Hypotrichia, Uronychiidae): Cortical Structure and Morphogenesis during Division

Morphogenesis of cell division was investigated in Uronychia transfuga utilizing both light microscopy of living and stained specimens and SEM of preserved specimens. The cortical morphogenetic pattern of Uronychia is similar in several respects to that of the members of the family Euplotidae. These features include: the de novo development of the opisthe oral primordium in a subcortical pouch; the development of frontoventral and transverse cirri for both the proter and opisthe from 5 cirral primordia that form de novo within a single latitudinal developmental zone; and the absence of right marginal cirri. The members of the genus Uronychia also show a number of unique characteristics: development of a proter oral primordium that causes partial replacement of the parental adoral zone of oral polykinetids during development of the proter; a large oral membrane that is divided into a right and left component; large caudal cirri that bend to the left; and dorsal kineties comprised of closely set paired-kinetosome kinetids. When compared to the other euplotid-like ciliates, these unique features support the placement of the genus Uronychia in a separate family, Uronychiidae.     

一种游仆虫无性分裂生殖的研究Ⅱ.无性分裂过程中皮层结构的形态发生

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。     

Divisional morphogenesis in the marine ciliate, Hemigastrostyla enigmatica (Dragesco & Dragesco-Kernéis, 1986) and redefinition of the genus Hemigastrostyla Song & Wilbert, 1997 (Protozoa, Ciliophora)

Morphogenetic events during the division of the marine hypotrichous ciliate, Hemigastrostyla enigmatica (Dragesco & Dragesco-Kernéis, 1986) Song & Wilbert, 1997 are described. The morphogenesis is characterized by:(1) 5 frontoventral-transverse cirral anlagen develop into 8 frontal, 5 ventral and 5 transverse cirri after Oxytricha-pattern;(2) there may be 6 FVT-anlagen in some individuals giving rise to more cirri which, however, will be resorbed after division;(3) anlage of the right marginal row at least in the opisthe occurs de novo right to the parental structures instead of within them;(4) according to the origin, the two extra ventral cirri right to transverse ones are not ventral or transverse cirri, which are from the retained old structure;(5) dorsal kineties originate from one group of DK-anlagen in both dividers with, very uniquely, an additional fragmentation of DK1, and(6) oral primordia will be formed in both dividing parts, from which the newly-built membranelles in the proter replace the posterior part of the parental AZM with a particular 'piecing together mode.Some features during the morphogenesis (e.g. variable number of cirral anlagen, presence of primary primordia, the mode of rebuilding of the proter's adoral zone of membranelles, origin of dorsal kineties and caudal cirri etc.) indicate that the genus Hemigastrostyla might present a intermediate form between oxytrichids and other related higher taxa. Based on our new observations, an improved diagnosis for genus Hemigastrostyla is given: marine or brackish water Oxytrichidae with slightly to conspicuously cephalized body shape; mostly 8–10 frontal, 5 ventral, 5 transverse and two to several extra ventral cirri to the right of the transverse ones, which are from the retained parental structure; caudal cirri present.     

钩刺斜管虫无性生殖期间的口纤毛器及细胞发生研究（原生动物：纤毛虫）

钩刺斜管虫口和体纤毛器演化模式是研究该类动物个体发生的优秀模型。通过跟踪研究,澄清了后仔虫口器发生以及体纤毛器起源上的几点疑问,并证实：体左侧二列片段动基列为同源再造而非来自老结构的分裂或复制;三列围口纤毛均为双动基列构造;后仔虫口原基场的构建系由５列体动基列共同参与完成的,其中最左侧两列短的原基片段与原基１整合为一体,从而发展成营养期虫体的外围口动基列;后仔虫背触毛原基为独立发生。     

阔口尖毛虫无性生殖和生理改组过程的比较

阔口尖毛虫无性生殖中先后发生后口围带原基,前、后的波动膜原基,额腹横棘毛原基和左、右缘棘毛原基,老口围带也在此期间更新,结果形成2套新纤毛结构,原老结构瓦解消失;生理改组时按同样顺序产生口围带原基等几类腹面纤毛原基,结果形成1套新纤毛结构,替换老结构。在这两个截然不同的过程中,新纤毛结构的分化和老纤毛结构退化时也表现出某些相似的特征。作者据此推测,这种纤毛虫无性生殖和生理改组中,纤毛原基的发生、发育和定位在细胞控制机理上可能是相同的。     

红色角毛虫的形态学和形态发生过程的研究

观察并描述了上海采集到的红色角毛虫的形态结构和形态发生过程。发现形态发生时虫体分别于前、后两个区域发生前、后两个口围带原基,并且由同一个体分裂而成的前,后两个仔虫内,额、腹、横棘毛和缘棘毛的分化并不完全相同,以至造成两个仔虫上棘毛的数目和缘棘毛的列数有明显差异。根据红色角毛虫的形态结构及其形态发生中的一些不够稳定的特点,推测它可能是一种还处于分化中的腹毛类纤毛虫。     

四核舍太虫的细胞发生学与Helix E10-1二级结构分析

利用蛋白银染色技术,观察和研究海洋游仆虫-四核舍太虫Certesia quadrinucleata(纤毛门,游仆目)二分裂期间的形态发生学。其主要特征如下:(1)老口围带完全被前仔虫继承;(2)后仔虫口原基独立产生于皮膜深层;(3)老口侧膜参与前仔虫口侧膜原基形成,前后仔虫的口侧膜原基均发生于细胞表面, 向前贡献出第一根额腹棘毛;(4)额-腹-横棘毛以初级5原基模式产生, 且以"3:3:3:3:3"的方式分化出新的棘毛;(5)背触毛与左缘棘毛原基均来自老结构, 无尾棘毛产生。研究首次给出了背面纤毛器的发生图示,为进一步探讨舍太虫的系统地位提供了一份补足性的发生学基础资料。游仆目纤毛虫的核糖体小亚基基因HelixE10-1区域二级结构一共存在9种模式, 该区域序列长度的变异性揭示了游仆目纤毛虫在进化中可能处于比较特殊的地位。       

尖前口虫的口器发生研究(纤毛门, 膜口目)

研究了咽膜类纤毛虫尖前口虫无性生殖期的核器及口器的演化.其发生特征为;1)新的口原基形成于原前庭动基列与口侧膜间,表观为原口侧膜分裂而致;2)随着形态发生的进行,由口原基依次演化出后仔虫的三片咽膜、口侧膜和三条前庭动基列;3)原口器完全被前仔虫所继承;4)体纤毛器在整个形态发生过程中一直保持双动基列结构.       

Morphogenesis of the marine spirotrichous ciliate, Trachelostyla pediculiformis (Cohn, 1866) (Ciliophora, Stichotrichia), with consideration of its phylogenetic position

The cortical development during binary fission of the relatively poorly known stichotrich ciliate, Trachelostyla pediculiformis (Cohn, 1866) Borror, 1972, found in coastal waters near Qingdao, China, was investigated using the protargol impregnation method. The morphogenetic process reveals some pretty unusual characteristics, which do not follow the Oxytricha-pattern: (1) the parental oral apparatus is entirely renewed from an oral primordium formed de novo in the proter; (2) in the proter, the parental undulating membranes are not involved in the formation of the newly formed oral primordium; both undulating membrane-anlagen (UM-anlage) and frontoventral-transverse cirral anlagen (FVT-anlagen) develop from the oral primordium in the proter; (3) the dorsal kineties (DK) are generated in a unique way, that is, in both dividers, two separate groups of DK-anlagen develop in the right- and left-most DK, generate all the DK and evolve to replace the old structures; (4) three caudal cirri are formed at the posterior ends of three right-most dorsal kinety anlagen; (5) eight frontal, five ventral and five transverse cirri are derived from six streaks, namely, the UM-anlage and 5 FVT-anlagen; the cirri are segregated from these anlagen in the pattern 1:3:3:3:4:4 (from left to right) in the Oxytricha mode. Based on both SSrRNA gene sequencing and morphogenetic data, the systematic positions of the genus Trachelostyla Borror, 1972 as well as the family Trachelostylidae Small and Lynn, 1985 are briefly analyzed. The results indicate that this genus/family could be a highly isolated lineage and might be ancestral to other well-known oxytrichids.     

Morphogenesis in the Heterotrich Ciliate Climacostomum virens. I. Oral Development During Cell Division

The principal characteristics of stomatogenesis during division in Climacostomum virens are: (A) Kinetosomal proliferation on the left side of a variable number of kineties in the ventral somatic cortex forms an oral primordium consisting of several kinetosomal fields, which then fuse to form a single anarchic field. (B) A constant topographical relationship exists between the primordium and a well defined cortical pattern, the zone of discontinuity. (C) The anarchic field primordium divides into 2 unequal parts—to the left, the AZM primordium, and to the right, the paroral primordium, which differentiates into the apical membranelles, the peristomial field, and the buccal tube. (D) Preoral and oblique kineties of the somatic cortex form along the right side of the paroral primordium. (E) Parental oral structures are partially dedifferentiated. Stomatogenesis in C. virens and other heterotrichs is compared.     

Cortical structure in non-dividing and dividing Diophrys japonica spec. nov. (Ciliophora, Euplotida) with notes on morphological variation

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.     

Morphology,ontogenesis and molecular phylogeny of a new saline soil ciliate,Uroleptoides salina nov. spec. (Ciliophora,Hypotrichia)

The morphology, morphogenesis and molecular phylogeny of a new saline soil hypotrich ciliate, Uroleptoides salina nov. spec., discovered from China, was investigated. The new species is characterized as follows: body 150–215 × 40–50 μm in vivo, slender and highly flexible; usually four ellipsoidal macronuclear nodules; contractile vacuole absent; cortical granules absent; endosymbiotic algae present; amphisiellid median cirral row consists of 14–25 cirri and terminates about 47% down length of body; usually three buccal cirri and 3–13 cirri left of anterior portion of amphisiellid median cirral row; 3–5 transverse cirri. Morphogenesis during binary fission is characterized by: (1) the parental adoral zone of membranelles is retained completely, parental paroral contributes to the formation of the undulating membranes anlage for the proter; (2) the oral primordium of the opisthe is formed apokinetally; and (3) the amphisiellid median cirral row is formed from two anlagen. Phylogenetic analyses based on SSU rDNA sequence data show that Uroleptoides salina nov. spec. has a close relationship with its morphologically similar species, U. longiseries, U. magnigranulosus, Orthamphisiella breviseries, and Parabistichella variabilis.     

Morphogenesis of a unique pseudourostylid ciliate,Trichototaxis songi (Ciliophora,Urostylida)

Divisional morphogenesis in the freshwater spirotrichous ciliate, Trichototaxis songi Chen et al., 2007, was investigated. The main morphogenetic events are characterised as follows: (1) the parental oral apparatus is completely renewed by the independently formed oral primordium in the proter; (2) the oral primordium in the opisthe is formed on the cell surface; (3) several left cirri of the midventral pairs participate in the formation of the oral primordium in the opisthe; (4) FVT-anlage I forms the leftmost pair of the bicorona; (5) the macronuclear nodules fuse into many masses rather than a single or branched mass as described in most pseudokeronopsids; and (6) usually, two marginal anlagen develop within each left marginal row separately. However, the number of left marginal anlagen is highly variable, even differing between the proter and opisthe of the same divider. The increase in the number of left marginal anlagen is by de novo generation of small anlagen to the left of the intrakinetal left marginal anlage, whereas the decrease in number is by resorption of the old marginal row(s). We posit that Trichototaxis is an intermediate form between the Pseudourostylidae and Pseudokeronopsidae as it shares morphogenetic features with both. Additionally, as in Uroleptopsis (Uroleptopsis), FVT-anlage I forms the leftmost pair of the bicorona in Trichototaxis indicating these genera may be closely related.     

Morphology and Morphogenesis of a Novel Saline Soil Hypotrichous Ciliate,Gonostomum sinicum nov. spec. (Ciliophora,Hypotrichia, Gonostomatidae), Including a Report on the Small Subunit rDNA Sequence

Morphology, cirral pattern, and morphogenesis of the new saline soil hypotrich, Gonostomum sinicum nov. spec. collected from Longfeng Wetland in Daqing, north China, were studied, using detailed live observations and protargol‐stained specimens. The new species is characterized as follows: (i) a size in vivo of 100–125 × 30–40 μm, (ii) colorless cortical granules, 0.5 μm across, arranged in short rows, (iii) an adoral zone composed of 28–33 membranelles, (iv) three or four frontoventral rows, one of which extends onto the postoral area, (v) left and right marginal rows composed of 18–27 and 21–35, cirri, respectively, and (vi) usually two transverse cirri. Morphogenesis is as usual for the genus Gonostomum, i.e. the cirral primordia II–VI are primary primordia which split into two sets for proter and opisthe in division middle stages, except for anlage I which develops independently. However, the number of frontoventral transverse anlagen is either five or six not only in different individuals but even in proter and opisthe of the same divider. The phylogenetic analyses based on SSU rDNA sequences showed that the genus Gonostomum is nonmonophyletic, indicating that the patterns of cirri and dorsal kineties are homoplasious characters. The new species G. sinicum nov. spec. is perhaps closely related to Cotterillia bromelicola and two congeners.     

海洋尾丝虫无性生殖期间口器发生的再研究

利用蛋白银技术研究了海洋纤毛虫—海洋尾丝虫无性生殖期间的口器发生过程。结果显示其口器发生与已知的同属种类具相似的过程和形式。其口器发生及演化的基本模式可表示如下 :后仔虫的小膜 1、小膜 2来源于老口侧膜后段的增殖 ;后仔虫的口侧膜及盾片来源于老口侧膜前段的增殖 ;后仔虫的小膜 3来自于老口区盾片的增殖 ;前仔虫的口侧膜及盾片来源于老口侧膜 ,三片小膜在口器发生过程中被保留。文中根据现有的形态发生资料对尾丝虫科的系统关系进行了探讨