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1.
本新种的典型特征为表膜较薄但不弯曲,无表膜下颗粒;区别于该属其它种的最突出特点是具有多个大核(5.4±1.4);背触毛6列,在第3-4列之间具有一些额外散在的背触毛.口围由42.3±2.2片小膜组成;额、腹、横、尾棘毛恒为8553结构;本新种的形态发生结果与该属其它种类相同,6列新背触毛原基分别来源于背部的3列老背触毛和腹部的老右缘棘毛,在第3及第4列新背触毛列之间可见新出现并散在的几根背触毛.  相似文献   

2.
应用能同时显示纤毛虫的皮膜结构及核器的蛋白银染色方法,研究了急纤虫Tachysoma pellionella的形态及其无性生殖周期中核器和纤毛器的发育演化过程。其中的形态发生过程是:(1)大核改组带出现后,在口围带(AZM)和腹棘毛VC4、VC5之间形成一条细线,于细线中发生许多成群的毛基体,逐渐演变成为后AZM原基区。最终,原基区颗粒组装成一片片整齐排列的小膜,它们构成为新AZM。老AZM也伴随着由基部向前更新,(2)在额棘毛FC5-FC8和腹棘毛VCl-VC3全部瓦解时紧接着产生前、后波动膜原基和新棘毛原基区,并发生波动膜的分化,棘毛的分化、移动和定位过程;(3)左、右缘棘毛原基的发育形式相同,但右缘棘毛原基的发育稍早。在右缘棘毛列中的第2(或第3)根和约第16根棘毛、左缘棘毛列的第1根和约第17根棘毛开始,随老棘毛基部的瓦解,于老棘毛基部位置各产生前、后两部分新缘棘毛原基,左、右每部分原基各占据了约六个老棘毛基部位置后分别朝所在的老棘毛列的外侧、内侧向后伸展开来;(4)在第1—3列背触毛中分别于每列之前、后两部分的中部范围产生前、后第1—3列新原基,每列原基向其两端伸展替代老背触毛列,它们后来成为前、后仔虫的相应的第1—3列新背触毛。接着在前,后各第3列背触毛原基后端发生前、后第4列原基,并稍偏向第3列原  相似文献   

3.
背联体贻贝棘尾虫的每一虫腹面含有相当于正常棘尾虫的腹面纤毛系统,背联两虫任意一侧属于一虫的背面有4列背触毛,它们的排列分布相似于正常棘昆虫的第1—4列背触毛,另一虫背面打2列背触毛,它们相似于正常棘尾虫的第5、6列背触毛。结果表明,背联体棘尾虫是其中两虫各以背面第4列和第5列背触毛之间的皮层区相联接形成的。也有的背联体中背部皮层联接区有变化。无性分裂中背联两虫皮层纤毛结构的形态发生相似于正常棘尾虫,并且两者其皮层纤毛器如口围带、额腹横棘毛、左、右缘棘毛和背触毛等相应结构的发育是同步进行的,推测背联两虫的皮层发育既是相对独立的,又有某种机制控制着相互间的协调。背联体棘昆虫在无性生殖周期中总是经历着一个调节成单体的过程,认为这于背联两虫都具有一套结构功能正常的运动胞器(特别是口围带),而产生向不同方向运动的“不协调”的力有关。  相似文献   

4.
通过活体观察和蛋白银染色法对采自青岛沙滩半咸水的变藓棘毛虫Sterkiella histriomuscorum(纤毛门, 腹毛目)进行了形态学及细胞发生学研究。该种群形态学与前人报道的土壤及淡水种群基本一致: 虫体近长椭圆形, 活体大小约(100-160) m (40-75) m; 无皮层颗粒; 2938片口小膜; 额棘毛3根; 额腹棘毛4根; 口后腹棘毛3根; 横前腹棘毛2根; 横棘毛3-5根; 左右缘棘毛列分别由17-23、20-24根棘毛组成; 6列背触毛; 2枚大核。其主要发生学特征如下: (1)老口围带完全保留, 老波动膜解体重建; 后仔虫口原基独立发生; (2)额腹横棘毛为5原基次级发生式, 部分原基来自老棘毛解体, 以2:3:3:4:4方式分化为新棘毛; (3)缘棘毛原基产生于老结构中, 并向两极延伸逐渐形成前后仔虫的新结构; (4)背触毛发生为典型Oxytricha模式; (5)大核在发生过程中完全融合。研究对首次在半咸水生境中发现的变藓棘毛虫种群进行了活体形态学和纤毛图式描述, 补充了显微照片、性状统计数据及发生过程的细节信息。    相似文献   

5.
本文报道来自黑龙江省帽儿山地区的尖毛虫科一新种,史氏尖毛虫Oxyrichashiisp.nov,对其形态,纤毛器,纤毛图式及相近种的异同做了比较研究。结果表明:新种具该科及属的典型特征,体柔软可曲,具球形成纵列并聚集成“簇状”的表膜下颗粒;口旁小膜带由(51.7±2.1)片小膜组成;额、腹、横、尾棘毛恒为8:5:5:3结构;背触毛8~9列。3根尾棘毛可自基部摆动。  相似文献   

6.
尾柱虫(Urostyla cristata)的形态发生研究   总被引:2,自引:0,他引:2  
U.cristata的表膜“纤毛图式”的构成多而复杂,棘毛大小、基部形状都不相同。在分裂时期产生四个新原基(primordium)区域:(1)口原基(AZM和PM),(2)额部、腹部和臀部棘毛原基(FVT),(3)缘棘毛原基和(4)背触毛原基。 U.cristata在无性分裂时,以口原基的出现为第一迹象,PM和No.O棘毛及腹棘毛中部分棘毛产生新原基居中,而以缘棘毛和背触毛产生原基为最后。分裂过程中,后仔虫上的PM是在新AZM原基的右边产生的,而前仔虫上的老PM则在原位从上往下开始更新的,老AZM是在原位从下往上更新的。左右两边缘棘毛都是在最左一条棘毛排上出现上下两个原基区域的。背面各排触毛的原基是在虫体长1/3和2/3两个位置上出现的。  相似文献   

7.
游仆类是纤毛虫中进化最为复杂和高等的一大类群,为了进一步探索和完善游仆类的多样性,本研究利用活体观察、蛋白银和银浸法染色技术对采自青岛小西湖的小腔游仆虫(Euplotes aediculatus)的形态学及细胞发生学进行了详尽的研究,并在完整的形态学及发生学研究基础上,测定了小腔游仆虫的核糖体小亚基基因(SSU r DNA)序列,通过序列比较和分子系统树构建等方法,对小腔游仆虫的系统地位进行了分析。结果表明:本种鉴别特征为9根额腹棘毛,5根横棘毛,2根缘棘毛,2根尾棘毛,8列背触毛,double-eurystomus型银线系。发生学特征包括:(1)后仔虫口原基在表皮下独立发生,前仔虫完全继承老口围带;(2)额–腹–横棘毛原基从左向右按照3:3:3:2:2的模式形成额腹棘毛和横棘毛;(3)前后仔虫最左侧额腹棘毛分别由独立产生的原基形成;(4)缘棘毛原基独立发生;(5)初级背触毛原基来自虫体中部老结构的反分化;(6)前后仔虫尾棘毛分别来自最右侧2列背触毛原基和老背触毛列末端;这些特征显示出游仆虫属个体发生模式的高度保守性。分子系统分析与形态学数据一致,即游仆虫属为单元发生,且小腔游仆虫与艾美游仆虫(Euplotes amieti)、阔口游仆虫(E.eurystomus)和伍氏游仆虫(E.woodruffi)聚在一起。  相似文献   

8.
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   

9.
对目前已发表下毛目纤毛虫的200个属级阶元进行了重新修订.给出新修订的下毛目系统,并根据其纤毛图式和形态发生特点将其归为5亚目20科82属.原下毛亚目Protohypotrichina suborder nov.,翁柯虫科Onychodromusidae fam.nov.,腹柱虫科Gastrostylidae fam.nov.和拟角毛虫属Parakeronopsis gen.nov.为新设,给出了下毛目中各亚目和科的特征简述及亚目及科的检索表.各属的特征以特征简述、检索表以及属的模式图的形式介绍之.新立原下毛亚目Protohypotrichina suborder nov.,并对排毛亚目Stichotrichina中的科属进行了重新修订.原下毛亚目的特征为无明确缘棘毛分化;排毛亚目的特征为无明确额腹横棘毛分化,腹棘毛为长的纵列,数目多,形式多样.修订后的原下毛亚目含2科3属,排毛亚目含5科29属.各科的基本特征分别为:原毛虫科Phacodinidae无明确体棘毛和背触毛的分化;凯毛虫科Kiitrichidae体纤毛器背腹有明确分化,有原始的背触毛分化;旋毛虫科Spirofilidae腹棘毛旋列或斜向排列;卡尔虫科Kahiellidae左、右缘棘毛均2至多列;小双虫科Amphisiellidae具1纵向排列的腹棘毛列;角毛虫科Keronopsidae具2列纵向排列的腹棘毛,通常无额棘毛及横棘毛的分化;翁柯虫科Onychodromusidae腹棘毛通常多列,一般有额、腹、横棘毛的初步分化;给出了各科及属的检索表,并附各属纤毛图式,对部分属进行讨论.  相似文献   

10.
本报道采自黑龙江省帽儿山地区的尖毛虫科一新种,史氏尖毛虫Oxytricha shiisp.nov.,对其形态,纤毛器,纤毛图式及相近种的异同做了比较研究,结果表明:新种具该科及属的典型特征,体柔软可曲,具球形成纵列并聚集成“簇状”的表膜下颗粒,口旁小膜带由(51.7±2.1)片小膜组成,额、腹、模、尾棘毛恒为8:5:5:3结构,背触毛8 ̄9列,3根尾棘毛可自基部摆动。  相似文献   

11.
The morphology and morphogenesis of a new marine hypotrich ciliate, Apokeronopsis bergeri nov. spec., collected from mussel-farming waters near Qingdao, China, are described from living and protargol-impregnated specimens. This ciliate has characteristics that place it in the family Pseudokeronopsidae, namely, two long rows of frontal cirri (bicorona), which are continuous with the long midventral rows, and a single row of marginal cirri on each side of the body. It shares with its only congener, Apokeronopsis crassa, the long rows of buccal and transverse cirri and the wide spacing between the midventral rows of cirri. These characters separate the genus Apokeronopsis from Pseudokeronopsis, which has a single buccal cirrus, fewer transverse cirri and midventral rows of cirri arranged in a typical zig-zag pattern. A. bergeri differs from A. crassa in its shape, colour and in the numbers of membranelles and transverse cirri. Although morphogenesis in A. bergeri is similar to that of A. crassa in most respects, the mode of formation of the buccal cirri is slightly different. The close relationship of A. bergeri with A. crassa, and the more distant relationship with three Pseudokeronopsis species, is supported by a comparison of the sequences of their ITS1-5.8S-ITS2 rDNA regions.  相似文献   

12.
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   

13.
In a study on ciliate diversity, we discovered the new hypotrich species, Gonostomum jangbogoensis n. sp., in freshwater from Terra Nova Bay, Victoria Land, southeast Antarctica. We describe its morphology and morphogenesis using standard methods, and the SSU rRNA gene phylogeny is provided as well. Morphology of Gonostomum jangbogoensis n. sp. is characterized as follows: slender to elongated body shape; grayish under low magnification; cortical granules present; 32–41 adoral membranelles; 3 enlarged frontal cirri; 1 buccal cirrus; 2 frontoterminal cirri; 3 or 4 frontoventral cirral pairs, 2 pretransverse cirri, 6–7 transverse cirri; 13–19 left and 18–26 right marginal cirri; 17–23 paroral kinetids; 3 dorsal kineties; 3 caudal cirri; 2 macronuclear nodules with 1–3 micronuclei. The morphogenesis of the new species confirms that it has at least seven frontal-ventral-transverse cirral anlagen, which is also reported in Gonostomum sp. 1 sensu Shin from Korea. Even though these two populations occur very far from each other, the morphometric data prove that this character state, the seven cirral anlagen, is a stable feature across these populations and might be an apomorphy. The phylogenetic analyses show that the genus Gonostomum is non-monophyletic and that the new species is a sister to G. bromelicola.  相似文献   

14.
The morphology and morphogenesis of a marine ciliate, Epiclintes auricularis rarisetus nov. sspec., collected from Qingdao, northern China were studied on live and protargol-impregnated specimens. This isolate can be recognized by its elongate, contractile and tripartite body with a size of 200-400×20-40 μm in vivo, about 30 ventrally located adoral membranelles, short undulating membranes, 2-3 frontal and 10-18 transverse cirri as well as 8-9 fronto-midventral rows, 22-31 left and 35-54 right marginal cirri, but no caudal cirri, invariably 3 dorsal kineties, of which kineties 1 and 3 link together anteriorly, 24-70 macronuclear nodules, marine habitat, and contribution of almost all frontal-midventral transverse cirral anlagen (FVT anlagen) to the formation of fronto-midventral rows. In its divisional morphogenesis, this species demonstrates some features rarely if ever found in any other urostyloids, e.g. partial replacement of the old adoral zone of membranelles, de novo formation of the oral primordium and the anlagen for marginal rows and dorsal kineties, contribution of almost all FVT anlagen to the transverse cirri, lack of frontoterminal cirri. In addition, its morphogenesis appears to differ in detail from that of E. auricularis auricularis nov. stat., based on published data. These remarkable morphogenetic traits of Epiclintes suggests a questionable systematic position for this genus in the Urostyloidea, therefore, further researches are urgently needed.  相似文献   

15.
The morphology, morphogenesis, and molecular phylogeny of Bakuella (Pseudobakuella) guangdongica n. sp., isolated from southern China, were investigated. The new species is characterized by a body length of 150–225 μm in vivo; 35–42 adoral membranelles; 3–5 buccal, two frontoterminal, 7–12 transverse and two pretransverse ventral cirri; midventral complex comprised of 10–20 pairs and two rows extending to transverse cirri; posterior part of marginal rows slightly overlapping; colorless cortical granules about 1 μm across, arranged in small groups; soil habitat. Its main ontogenetic features are: (1) in the proter, the parental adoral zone of membranelles is completely renewed by new structures; (2) in the opisthe, the oral primordium originates apokinetally, some old midventral cirri join the formation of frontoventral-transverse cirral anlagen; (3) the anlagen for marginal rows and dorsal kineties develop intrakinetally; and (4) the numerous macronuclear nodules fuse into a single mass before dividing. Phylogenetic analyses based on the SSU rDNA sequence suggest the non-monophyly of the genus Bakuella.  相似文献   

16.
The morphogenesis of the stichotrichous ciliate, Neokeronopsis spectabilis, collected from a freshwater pond near Harbin, north China, was observed following protargol impregnation. The overall morphogenetic events are characterized by: (1) the new oral primordium originates in association with the transverse cirri; (2) the proter's undulating membrane anlage is formed following the dedifferentiation of the parental endoral and paroral membranes, while the old adoral zone of membranelles is retained; (3) the fronto-ventral-transverse cirral anlagen originate independently on the right of the proter's undulating membrane anlage; (4) the left and right marginal cirri are derived from new anlagen that originate within the old marginal rows; (5) the generation of the dorsal kineties is of the "two-group-mode" with fragmentation and hence an oxytrichid pattern; and (6) similar to that in oxytrichids, the caudal cirri are formed at the posterior ends of the rightmost and two leftmost kineties of the group 1. Some new morphological data for N. spectabilis are also presented and the systematic position of the genus Neokeronopsis is briefly discussed. We conclude that its position among the urostylids is peripheral and that it very likely represents an intermediate form between the oxytrichids and urostylids.  相似文献   

17.
18.
Hu  Xiaozhong  Song  Weibo 《Hydrobiologia》2001,448(1-3):171-179
The morphology and morphogenesis of the marine hypotrichous ciliate Holosticha heterofoissneri nov. spec. from mollusc culture in Qingdao, China are described based on living and protargol-impregnated specimens. The new species is characterized by: adoral zone slightly bipartite, consisting of on average 43 membranelles; constantly 5 dorsal kineties, and 12 pairs of cirri in midventral rows, and 14–16 macronuclear segments, which differs from the closely related species, H. foissneri. Its morphogenetic process shows the following features: (1) the parental AZM is retained unchanged and will be inherited by the proter, only the old UM reorganized; (2) FVT-cirral anlagen in both division parts derive from the breaking of primary primordia; (3) during the formation of FVT-cirral anlagen, most midventral cirri remain intact; and there appears an 'extra' anlage (EA) between the UMA and other FVT-cirral primordia; (4) the generation type of the dorsal kineties is of 'one group mode', the leftmost one of the 4 primordia fragmentates to form a new kinety; (5) at the early stage of morphogenesis, replication bands of macronuclear segments are apparently present.  相似文献   

19.
The morphology and morphogenesis of a new soil hypotrich ciliate, Sterkiella multicirrata sp. nov., was investigated using live observation and protargol staining. The new species is characterised by: body elliptical, 110–180 × 45–75 μm in vivo, an average of 35 adoral membranelles; usually 19 frontoventral‐transverse cirri, consisting of three frontal, five frontoventral, one buccal, four postoral ventral, two pretransverse, and four transverse cirri; four macronuclear nodules, and 2–5 micronuclei. S. multicirrata sp. nov. differs from its congeners mainly in the number of frontoventral‐transverse cirri and macronuclear nodules. Morphogenesis of the new species is similar to its congeners; the primary difference exists in the segmentation of the frontoventral‐transverse cirral anlagen, which is usually generated in a 1:2:3:3:5:5 pattern. Based on the small subunit ribosomal DNA sequence, the phylogenetic position of the new species is discussed.  相似文献   

20.
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   

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